WHO/FOOD ADD/71.42



    Issued jointly by FAO and WHO

    The content of this document is the result of the deliberations of the
    Joint Meeting of the FAO Working Party of Experts and the WHO Expert
    Group on Pesticide Residues, which met in Rome, 9-16 November, 1970.



    Rome, 1971



    Since the previous comprehensive evaluation (FAO/WHO, 1968) additional
    information has become available and is summarized and discussed in
    the following monograph addendum.


    Because the conversion of aldrin to dieldrin appears to be the primary
    metabolic step in all mammalian species studied, the data summarized
    in this section can be considered to be applicable to aldrin also.


    Absorption, distribution and excretion

    The concentration of dieldrin in blood and liver of rats fed 50 ppm
    increased for nine days and then remained fairly constant during the
    remaining six months; after 16 days the dieldrin level in the fat also
    reached a relatively constant value. The mean ratios after equilibrium
    was reached were approximately 1 : 30 : 500 for blood, liver and fat
    respectively (Diechmann et al., 1968).

    It was found that highest concentrations of dieldrin in rats fed 10
    ppm were found in the fat followed by the liver, brain and blood in
    that order. The half-lives of dieldrin in the fat and brain were
    estimated to be ten and three days respectively. (Robinson et al.,

    In the rat reproduction study described below, the average
    concentration of dieldrin in body fat was 18 times that in the diet,
    and in the maternal milk it was 17 times greater. The maximum
    excretory rate was estimated at 0.42 mg/kg body-weight per day and the
    maximum excretion in milk was 1-4 mg per lactation period (Harr et
    al., 1970).

    In the two-year feeding study in rats and dogs, it was found that
    equilibrium in tissue concentrations in rats was attained after six
    months of feeding, the changes that occurred in the subsequent 18
    months being very small. A similar situation was evident with dogs,
    although an unexplained significant increase in the blood level of
    dieldrin occurred during the last six months of the study (i.e. after
    18 months' feeding). In female rats the tissue concentration of
    dieldrin was 2-10 times that of males fed the same dietary
    concentration; however, a similar sex difference was not noted with
    dogs (Walker at al., 1969a).

    The ratio of the concentration of dieldrin in human fat to that in
    blood, once equilibrium was established, was about 140, a ratio which
    is similar to that found with rats and dogs. After termination of
    feeding dieldrin, the estimated biological half-life was 369 days.
    Relationships between the intake levels of dieldrin and the levels in
    blood and fat were developed from these studies and have been applied
    to humans exposed to dieldrin (Hunter et al., 1969). See also
    "Observations in Man" (Jager, 1970).

    Of 43 workers who were removed from exposure to dieldrin, it was
    calculated that the half-life of dieldrin in these subjects was seven
    months. The mean dieldrin concentration in blood during the last half
    year of exposure was 0.1 ppm which corresponded to an average daily
    oral intake of 1.03 mg (about 0.17 mg/kg body-weight) (Jager, 1970).

    When dairy cattle were fed 0.1 mg/kg body-weight per day of dieldrin
    for four months, there was a sharp decline in the dieldrin content of
    the milk after two weeks cessation, and a further less marked decline
    after 11 weeks. (Braund et al., 1969).

    Male rats, with or without bile fistulas were given intravenous doses
    of 0.25 mg/kg body-weight of 14C-labelled dieldrin. In the intact
    animals the mean total recovery of radioactivity in the faeces, urine
    and carcasses was 96.9 percent of the original dose. Over 90 percent
    occurred in the faeces. In the animals with bile fistulas the mean
    total recovery was 86.9 percent of the original dose and over 90
    percent occurred in the bile. A comparison was made with the
    stereoisomer of dieldrin, endrin, which had more rapid faecal
    elimination or biliary excretion. The liver has been identified as the
    reason for the difference by in vitro studies using perfused liver.
    The results may explain the greater storage of dieldrin in the body
    than endrin (Cole et al., 1970).

    The concentration of dieldrin in the fat of pregnant women was 0.08
    ppm versus 0.17 ppm in the non-pregnant, a fact which suggests a more
    rapid metabolism of this insecticide during pregnancy. Dieldrin was
    also present in the maternal and umbilical cord blood and the foetal
    blood concentration was very close to that in the maternal blood.
    (Polishuk et al., 1970).


    Information available on the metabolism of dieldrin up to 1967 has
    recently been reviewed (Brooks, 1969).

    The mammalian conversion of aldrin to dieldrin has been known since it
    was first discovered in the mouse (Winteringham and Barnes, 1955).
    This reaction has been demonstrated in rabbit-liver microsomes and
    requires the presence of NADPH, the activity being destroyed by heat
    (Nakatsugawa et al., 1965).

    The enzyme involved is aldrin epoxidase, the activity of which appears
    to vary greatly, depending upon the preparation and the temperature of
    storage (Chan and Terriere, 1969).

    The information currently available on the various pathways of
    metabolism of dieldrin in mammals is based on in vivo and in vitro
    studies in several species, including the mouse, rat, rabbit, monkey,
    sheep and man (Baldwin and Robinson, 1970; Baldwin et al., 1970;
    Damico et al., 1968; Datta et al., 1965; Feil et al., 1970; Hedde et
    al., 1970; Klein et al., 1968; Korte and Arent, 1965; Matthews and
    Matsumura, 1969; Richardson et al., 1968; Robinson, 1970a, 1970b).
    Although there appears to be some sex and species differences in
    metabolism, the overall picture is summarized in Figure 1.



    In a comparative study on the metabolism of dieldrin in mice and rats
    administered 14C-labelled dieldrin, ten times more radioactivity
    appeared in the faeces than in the urine of both species. More
    unchanged dieldrin occurred in the rat urine than in mouse urine, and
    Klein's metabolite (III) was found only in rat urine. Other minor
    differences in urinary metabolites occurred between the two species,
    and in the mouse they were largely unidentified (Baldwin and Robinson,

    Some information on dieldrin metabolism has recently become available
    both in humans and in non-human primates. Neither unchanged dieldrin
    nor the urinary metabolites found in rats were identified in workers
    occupationally exposed to dieldrin or in monkeys fed dieldrin. The
    faeces contained the majority of the metabolites of dieldrin (Robinson
    1970a, 1970b).

    Effect on enzymes and other chemical parameters

    A study of the ultrastructural and biochemical effects of dieldrin and
    phenobarbitone upon the liver of rats, dogs and mice has been reported
    (Donninger et al. 1967; Donninger, 1969 and Wright et al. 1968), and
    the comparative effects have been reviewed (Potter et al. 1970).

    Rats were fed dieldrin at a dose of 8 mg/kg and phenobarbitone at 140
    mg/kg. Dogs were given 2.0 mg/kg of dieldrin and 20 mg/kg of
    phenobarbitone. Mice received doses of dieldrin ranging from 0.16 to
    7.5 mg/kg and doses of phenobarbitone between 1.2 and 120 mg/kg. In
    addition, the effect of the administration of 80 mg/kg of the
    carcinogen 4-amino-2,3-dimethylazobenzene (butter yellow) was studied
    in mice. Increase in the activity of microsomal enzymes was observed
    in all three species following the administration of dieldrin or
    phenobarbitone, while no increase was seen after butter yellow
    administration in mice. A marked increase in the liver smooth
    endoplasmic reticulum (SER) occurred in rats and dogs. Considerably
    less increase in SER was observed in mice. A further difference was
    that in the mouse the relative increase of DNA indicated that increase
    of liver-weight in the mouse was the result of new cell formation,
    while in the rat and dog there was cellular hypertrophy. No effect
    upon the ultrastructure of the mouse liver was observed following the
    administration of butter yellow. A progressive decrease in the
    activity of glucose-6-phosphatase was observed in the mouse liver
    following administration of butter yellow, while the activity of this
    enzyme was not changed following administration of dieldrin or
    phenobarbitone (Potter et al. 1970).

    Dieldrin was fed to male Rhesus monkeys at levels of 0.1, 0.5, 1.0,
    1.75 and 5.0 ppm (0.0002-0.07 mg/kg) in the diet for approximately six
    years. No significant liver changes were observed at dietary levels
    below 1.0 ppm. A dose-related increase in microsomal P450 was found at
    the higher levels. Increase of microsomal enzyme activity was observed
    at the two highest levels, but no changes in sub-cellular structure
    were found. (Wright et al., 1969, Zavon, 1970).

    A no-effect level for enzyme induction was established in rats at
    between 1 and 5 ppm of dieldrin (Gillett et al., 1968). Kinoshita et
    al. (1970) also established a diet level of approximately 1 ppm as the
    no-effect level. These workers observed the greatest amount of
    increase after one to three weeks of feeding with dieldrin.

    After an extensive study of workers in a manufacturing plant, it was
    concluded that no measurable microsomal enzyme induction occurs in man
    after long exposure to approximately 0.010 mg/kg/day. No evidence of
    enzyme stimulation was observed in a smaller group of workers
    absorbing higher amounts of dieldrin, up to 0.020 mg/kg/day (Jager,


    Special studies on carcinogenicity


    Groups of equal numbers (125-300) of male and female mice (CFI strain)
    were fed dietary levels of 0, 0.1, 1.0 or 10 ppm of dieldrin for
    periods of up to 132 weeks. In addition, a positive control group of
    50 mice received 600 ppm of the carcinogen,
    4-amino-2,3-dimethylazobenzene (butter yellow). Feeding was started at
    four weeks of age. The presence of liver tumours was detected
    initially by palpation, which was started on all animals after 16
    weeks of feeding, and the animals were sacrificed when the tumours
    became large enough to endanger health. No effect on health or
    behaviour was evident in the first nine months of feeding, and no
    liver tumours were detectable before 37 weeks at any dose level of
    dieldrin. The morbidity of the mice receiving 10 ppm of dieldrin
    increased after nine months, and at 15 months 50 percent of both sexes
    had either died or been sacrificed because of tumour size. The control
    group normally died after 20-24 months, and the life-span of the 0.1
    and 1 ppm group wan the same; these groups displayed no palpable
    masses. All the positive control group died after 14 months, although
    feeding of butter yellow had been terminated after six months when the
    first hepatoma appeared. Liver tumours increased in all test groups
    but not in other tissues. Tumours were of two types: type (a)
    consisted of solid cords of closely packed parenchymal cells with
    morphology and staining characteristics similar to the rest of the
    parenchyma. Little mitotic activity occurred, and growth appeared to
    be by expansion. These growths were classified as benign tumours. In
    the second type, type (b) tumours, a much more abnormal structure was
    present with areas of cells proliferating in confluent sheets and
    often with foci of necrosis. There were areas of papilliform or
    adenoid formation of liver cells with wide and irregular vascular
    channels within the growth. The mitotic activity was often increased
    and multinucleate forms were seen. On purely morphological criteria,
    the authors classified these tumours as hepatocarcinomas. They were
    very uncommon in the control group of mice. In a few cases these type
    (b) tumours had emboli of cells in the lungs. Dieldrin increased the
    incidence of both types of tumour (see Table I) but did not produce

    the fibrosis and bile duct proliferation sometimes observed in the
    mice given butter yellow. In order to determine if tumour-formation
    was reversible, certain mice from the group fed 10 ppm of dieldrin
    were transferred to a normal diet after 0, 2, 4, 8, 16, 32 or 64 weeks
    and sacrificed after 104 weeks. Incidence of tumours indicated that
    removal of dieldrin from the diet did not cause the tumours to regress
    or disappear. (Dieldrin also produced liver enlargement and
    cytoplasmic changes which were  reversible). In companion studies,
    sterilizing the diet or the bedding did not influence the incidence of
    tumours in mice fed dieldrin (Walker et al., 1970a).

    In connection with the increase in liver tumours arising in
    susceptible species of mice it is noted that the incidence of
    tumour-formation in C3H mice was also affected by variations in the
    diet (Tannenbaum and Silverstone, 1949a, 1949b) and in microbiological
    status (Roe and Grant, 1970).


    In groups of 25 male and 25 female rats fed 0, 0.1, 1.0 or 10 ppm of
    dieldrin for up to two years, the only pathological findings
    attributable to dieldrin were the existence of liver parenchymal cell
    changes in one male and four females fed 10 ppm. In one female,
    microscopic intrahepatic nodules were evident, and in addition nodules
    were observed after two years in two females fed 10 ppm and in one
    female in the control group (Walker et al., 1969a).

    Weanling rats were fed, for a lifetime, diets supplemented with
    aldrin, 0, 20, 30 or 50 ppm; dieldrin, 20, 30 or 50 ppm; or endrin, 2,
    6 or 12 ppm. Benign and malignant tumours were observed in 23 tissues
    or organs - in 199 of 800 experimental rats and in 79 of 163 controls,
    examined histologically. The highest number of tumours in all groups
    occurred in mammary and lymphatic tissues. When compared to the
    controls, male and female rats fed aldrin, 20, 30 and 50 ppm, and
    dieldrin, 20, 30 and 50 ppm, showed a dose-related significant
    decrease in the incidence of all tumours, particularly those of the
    mammary and lymphatic tissues. In male rats fed aldrin and dieldrin 50
    ppm, the tumour incidence was reduced from 46 (in 75 control rats) to
    13 (in 45 rats fed aldrin 50 ppm) and to one benign tumour (a skin
    papilloma) in 44 rats fed dieldrin. In the females fed aldrin and
    dieldrin 50 ppm, the total number of tumours was 23 in 41 and 16 in
    31, respectively, while the female control rats showed 104 tumours in
    88 rats. In all the 963 rats examined, no primary malignant hepatic
    tumours were found, only two benign hepatic hemangiomas, one in male
    control and one in a female fed endrin 6 ppm (Diechmann et al., 1970).

    Special studies on reproduction

    Bird embryos

    Exposure of chick, quail and pheasant embryos to aldrin produced an
    oestrogen-like effect in the male genital tract, leading to the

    persistence of the Mullerian ducts and a retardation of testicular
    development (Lutz-Ostertag and Lutz, 1969).

        TABLE I

    The percentage incidence of liver tumours in mice fed dieldrin for
    132 weeks


    Diet           Number    % Liver tumours (type)        % Secondary
    concn          of                                      tumour deposits
    (ppm)          animals   %(a)    %(b)     %(a+b)       in lung


    0              288       10      4        20           0.7 (1)*

    0.1            124       22      4        26           0.8 (1)

    1.0            111       23      8        31           0.9 (1)

    10.0           176       37      57       94           0.6 (1)


    0              297       13      -        13           -

    0.1            90        23      4        27           -

    1.0            87        31      6        37           1.1 (1)

    10.0           148       37      55       92           4.1 (5)

    Butter yellow
    600 ppm

    Males**        23        13      4        17           -

    TABLE I (cont'd)

    The percentage incidence of liver tumours in mice fed dieldrin for
    132 weeks


    Diet           Number    % Liver tumours (type)        % Secondary
    concn          of                                      tumour deposits
    (ppm)          animals   %(a)    %(b)     %(a+b)       in lung

    Females        21        43      38       81           9.5 (2)

    *   Figures in parentheses are the actual number of mice showing this

    **  The group of male mice fed 600 ppm of butter yellow had a 61 percent
        incidence of haemangiosarcomas and anaplastic sarcomas.

    Studies in the sparrow hawk have provided evidence that the decline in
    this species may be due to a failure in reproduction stemming from
    increased shell breakage (Lehner and Egbert, 1969; Porter and
    Wiemeyer, 1969), possibly caused by dieldrin.


    When groups of four male and six female quail were fed diets
    containing 0, 10, 20, 30 or 40 ppm of dieldrin for periods up to
    eighteen weeks, survival and reproduction were markedly affected at
    the 20, 30 and 40 ppm levels. At 10 ppm there was only a marginal
    effect upon survival, and reproduction was not greatly affected.
    Although egg production was reduced in the higher levels, even birds
    fed 40 ppm laid fertile eggs which had residues of over 50 ppm of
    dieldrin (Walker et al., 1969b).


    Groups of male and female mice were fed dietary levels 0 or 5 ppm of
    dieldrin for 30 days. Test and control mice were then randomly paired
    and were continued on the same diet for a further 90 days, there being
    a total of 101 pairs in the group fed dieldrin. Mortality in the test
    group was comparable to the controls, but the test group produced
    significantly smaller litters. There was, however, no difference in
    the time taken to produce the litters (Good and Ware, 1969).


    Rats were weaned at 28 days of age and then were started on diets
    containing dieldrin in ten two-fold levels from 0.01 to 40 ppm. The
    animals were sacrificed at ten equal logarithmic intervals up to 750
    days of age. In the females receiving diets containing 0.08 to 0.16
    ppm of dieldrin, the conception rate, rate of survival of young, and
    the number weaned were normal. At higher levels all these parameters
    decreased so that at levels greater than 2.5 ppm few young survived,
    and at 20 ppm none survived. The maximum dietary exposure which did
    not interfere with reproduction was 0.24 ppm (Harr et al., 1970).


    36 ewes were fed diets containing 0, 1.0, 5.0 and 25.0 ppm of dieldrin
    over a period of 40 months, including two gestation periods. No
    teratogenic effects were observed and reproductive performance was
    normal. However, at the 25 ppm level the lambs died shortly after
    birth (Harris and Greenwood, 1963).

    Special studies on the photoisomerization product of dieldrin

    Of various compounds that can arise due to the influence of sunlight
    on aldrin and dieldrin, an identified product, referred to as
    "photodieldrin" is the only product of any established importance; the
    corresponding "photoaldrin" is of negligible practical significance.
    Through the work of Robinson et al. (1965, 1966a), Parsons and Moore
    (1966), and Rosen et al. (1966), it has been established that
    "photodieldrin" has the cage structure A shown in Figure 2.

    Rats ware fed diets containing 10 or 30 ppm of the photoisomer for
    thirteen weeks. The animals were sacrificed at the end of the period,
    and brain, liver and fat were analysed. The presence of the unchanged
    photoisomer as well as the pentochloroketone (Klein's metabolite, B,
    found in dieldrin metabolism) was demonstrated (Baldwin and Robinson,
    1969a, 1969b).

    Exposure of dieldrin to ultraviolet light produced the
    hexachlorocyclo-isomer VII. This compound was produced in 7 percent
    yield after two months or in 25 percent yield after 12 months exposure
    to sunlight. The compound was found to be twice as toxic as dieldrin
    to the housefly and mosquito (Rosen et al., 1966; Robinson et al.,

    The photoisomerization product of dieldrin (photodieldrin) has been
    determined in a number of vertebrate species. Using oral or
    intragastric injection, either alone or in dimethylsulfoxide solution,
    it was found to be substantially more toxic than dieldrin in most
    species. Convulsions similar to those seen from dieldrin occurred
    prior to death. Table II summarizes the acute toxicity compared to
    dieldrin (Brown et al., 1967).



    Toxicity of the photoisomerization product of dieldrin 
    compared with dieldrin
          Species      Approximate LD50, mg/kg body-weight

                        product of dieldrin          Dieldrin

          Pigeon               90                     250

          Chicken              80                      48

          Mouse                 7                      77

          Rat                  10                      47

          Guinea-pig            3                      24

          Dog (M)             140                     120

          Dog (F)             100                      90

    Dieldrin or its photoisomerization product was fed to five male and
    five female mice at dietary levels of 1, 3 and 10 ppm for the
    photoisomerization product and 3, 10 and 3O ppm for dieldrin for one
    month. The mice exposed to the photoisomerization product were
    unaffected by 1 ppm, there was one male and one female death at 3 ppm
    and all died at 10 ppm. The mice fed dieldrin were unaffected by 3 or
    10 ppm, but three males and two females died at 30 ppm. Autopsies of
    the mice revealed no abnormalities (Brown et al., 1967).

    A similar experiment with rats produced no deaths from 10 ppm of the
    photoisomerization product; a higher level was not tested. Autopsies
    revealed no abnormalities. Levels were measured in the tissues; the
    biological half-life of the photoisomerization product was 1.7 for the
    males and 2.6 for the females, compared to 10.0 and 12.7 respectively
    for dieldrin (Brown et al., 1967).

    Subacute levels (5 mg per day) of 14C-labelled dieldrin or
    photodieldrin were administered to young adult rats of both sexes for
    a period of twelve weeks. Photodieldrin was given both orally and
    intraperitoneally; dieldrin was given by stomach tube only. About 60
    percent of the activity of 14C-photodieldrin was excreted in the
    urine and faeces of male rats and 47 percent in those of female rats,
    compared to 60 and 37 percent respectively with 14C-dieldrin. Females
    retained three-ten times more 14C activity in their tissues than did
    male rats after photodieldrin administration. A similar sex difference
    in tissue levels was found after administration of dieldrin and

    photodieldrin in female rats and of dieldrin in male rats. Extremely
    high levels of 14C activity were detected in the kidneys of male, but
    not female, rats receiving 14C-photodieldrin (Dailey et al., 1970).

    Storage of the photodieldrin was mainly in the fat and up to 10 ppm it
    was 2-15 times higher in females than in males. A metabolite of
    dieldrin was detected in the kidneys and urine. The concentration of
    this metabolite in the kidneys was about ten times that of the
    photodieldrin. No toxicologic effects were detected at 1 ppm (Walker
    et al., 1970b).

    Similar results were reported by Walton et al. (1970) who also found
    slight stimulation of liver microsomal enzymes.

    Photodieldrin was fed to groups of 12 male and 12 female rats at
    levels of 0.1, 1.0, 10 and 30 ppm in the diet for 13 weeks. Tremors
    were observed in rats in the 10 and 30 ppm groups. Reduced food intake
    and depressed growth also occurred at these levels. Two of the 10 ppm
    and six of the 30 ppm females died. Liver/body-weight ratios were
    increased in the 30 ppm groups and kidney weight was increased in the
    10 and 30 ppm males. Histologic liver changes were observed in the 10
    and 30 ppm groups (Walker at al., 1970b).

    Short-term studies

    Studies on the effect of dieldrin on the liver microsomal enzymes have
    been reviewed under "Biochemical aspects". The following additional
    studies have become available.


    Three groups each of six dogs of mixed sex were fed 0, 0.2 or 2 mg/kg
    body-weight of dieldrin by capsule for five days a week. The group
    given the low dose was started at 1.0 mg/kg for five days, then
    reduced to 0.2 mg/kg until day 62 and from then on given 2 mg/kg until
    signs of intoxication were evident. A direct relationship was found
    between the severity of symptoms and the blood concentration of
    dieldrin. As the blood level rose from 0.37 to about 0.8 ppm, changes
    progressed from a reduced food intake and growth reduction to the
    onset of muscular spasm and finally convulsions. A direct relationship
    was also found between blood and fat levels of dieldrin (Keane and
    Zavon, 1969).

    In an extension of the above-mentioned study, three groups each of six
    dogs of mixed sex were given a similar dose regimen of dieldrin. It
    was found that the period between dieldrin exposure and the onset of
    toxic signs was dependent upon the obesity of the animal; the greater
    the amount of body fat the longer it took for toxicity to develop.
    Since food refusal preceded symptoms of intoxication, forced feeding
    was able to suppress toxicity by preventing fat mobilization and the
    associated release of toxic concentrations of dieldrin into the blood
    stream, so avoiding the death of some animals (Keane et al., 1969).

    Groups of five male and five female dogs were given by capsule daily
    oral doses of 0, 0.005 or 0.05 mg/kg body-weight of dieldrin for
    periods up to two years. Health, behaviour and body-weight were
    unaffected by giving dieldrin, and the electroencephalograph readings
    showed no abnormalities. Urine and blood findings were normal except
    for an increase in plasma alkaline phosphatase after 30 weeks and a
    reduction in serum protein at the 0.05 mg/kg dose. Bromosulphthalein
    clearance was normal throughout the exposure period. Liver-weight and
    liver to body-weight ratios were increased in the females fed 0.05
    mg/kg, and decreased heart-weights, but not heart to body-weight
    ratios, were found in all males in the test groups and decreased
    spleen-weights at 0.05 mg/kg in the males. No abnormal gross or
    histopathological findings associated with administration of dieldrin
    were evident (Walker et al., 1969a).

    Long-term studies


    Dieldrin was fed to groups comprising 25 male and 25 female rats (45
    each for the controls) at dietary levels of 0, 0.1, 1.0 or 10 ppm for
    periods up to two years. In addition, a separate group comprising 15
    animals of each sex were sacrificed after six, 12 or 18 months
    feeding. Body-weight and food intake were unaffected by dieldrin, but
    at 10 ppm all the animals became irritable after eight or 13 weeks in
    the males and females respectively. Occasional convulsions occurred in
    this group during handling. No adverse effect on mortality was
    observed. There were no changes in haematology or serum enzyme levels
    attributable to dieldrin. Liver weights were normal for the first 18
    months of feeding, but after two years, increased liver weights and
    liver to body-weight ratios were evident in the groups fed 1 and 10
    ppm (Walker et al., 1969a).


    In a continuation of the study described in the previous monograph
    addendum on dieldrin (FAO/WHO 1968), the 12 male subjects were
    continued on the dose regimen of 0, 0.01, 0.05 or 0.21 mg of dieldrin
    for a total of two years and were further followed during an
    eight-month post-exposure period. All twelve men remained in excellent
    health, and there were no changes in body-weights, fatness or
    leanness, or other clinical abnormalities throughout the entire
    exposure and post-exposure periods. No departures from normal or
    pre-exposure values in the biochemical and haemotological parameters
    investigated were observed, although there was a slight trend towards
    a fall in plasma alkaline phosphatase activity in some men fed the
    higher dose levels. This drop was of doubtful significance, and the
    enzyme level returned to normal after two months post-exposure. The
    concentration of dieldrin in the blood did not significantly change in
    the groups given 0.05 mg/day, but at 0.21 mg/day there was a slight
    increase during months 18 to 21, but little over months 21 to 24.

    This increase was small compared to the first 18 months when the blood
    level tripled. Increase in dieldrin in adipose tissue was evident at
    all levels after administration for 92 days (Hunter et al., 1969).

    Extensive studies of workers exposed to dieldrin in a manufacturing
    plant have been reported. The average blood concentration of a group
    of 35 workers with an exposure of over ten years was 0.035 mg/ml,
    calculated to be equivalent to a dietary intake of 407 mg/man/day.
    Intoxications had occurred in some of these individuals prior to 1964.
    No definite deleterious effects were found in this high exposure
    group, including some individuals who had suffered intoxications.

    Clinical determinations, including SGOT, SGPT, LDH, alkaline
    phosphatase, total serum protein and serum protein spectrum,
    determined every three months remained within normal limits. In an
    extreme exposure group with blood levels above 0.2 ppm, alkaline
    phosphatase values, although within normal limits, were higher than in
    the control group.

    Using as criteria of possible microsomal enzyme stimulation the blood
    levels of pp'-DDE and the urinary ratio of 6-B-hydroxycortisol and
    17-hydroxycortico steroids, no differences between exposed and
    unexposed workers were found. The dieldrin workers were exposed to an
    average daily intake of 593 mg/man. One group of ten workers with the
    highest exposure had an average equivalent oral intake of 1224

    Comparisons of work records between exposed and non-exposed groups did
    not reveal any differences as to frequency or severity of diseases or
    accidents or disability (Jager et al., 1970). See also "Biochemical

    On the basis of fat samples only, Crabtree (1969) found in Australia a
    mean fat concentration of 0.3 ppm equivalent to an intake of 16
    mg/man/day. Bick (1967) reported lower figures while Wasserman (1968)
    reported higher ones. These last figures may be due to analytical
    errors (Lofroth, 1970).

    Wasserman et al. (1969) reported very low levels of dieldrin in fat
    tissues from South Africa. Jansen (1969), however, analyzing part of
    the same samples found a higher mean of 0.159 ppm, equivalent to an
    average absorption of 8.6 mg/man/day.


    The increased risk of development of liver tumours in mice exposed to
    dieldrin as compared with untreated control mice was regarded as the
    main matter for concern. This increased risk was seen even at an
    exposure level of 0.1 ppm in the diet. It was generally agreed that
    the tumours were neoplasms and that those seen in treated mice were
    similar in nature to those seen in untreated mice except insofar as

    the tumours in dieldrin-treated mice tended to show the same
    cytoplasmic changes as other liver parenchymal cells in the same

    There was no evidence that tumours regressed or disappeared after
    cessation of exposure to dieldrin, although the cytoplasmic changes
    did regress under such circumstances. It is difficult to establish
    unequivocal criteria for distinguishing between benign and malignant
    neoplasms in mouse-liver. The incidence of mice showing tumour emboli
    or metastases in the lungs was not significantly increased at any
    levels of exposure to dieldrin up to 10 ppm for 132 weeks.

    It was agreed that the effect of dieldrin in increasing the risk of
    tumour development in mice could not at the present time be regarded
    as sufficient evidence to categorize dieldrin as a carcinogen. Other
    work showed that nonspecific factors such as calorie intake, hormonal
    status and micro biological status may profoundly influence the risk
    of liver tumour development in mice, some strains of which are in any
    case peculiarly susceptible to each tumours. Also it was noted that
    long term studies in rats and prolonged studies in dogs and monkeys
    had revealed no evidence of hepatocarcinogenicity. It seems likely
    that the effect of dieldrin in mice is probably a species-specific

    Further information is urgently needed concerning the aetiology and
    pathogenesis of liver tumours in mice. A comparison of the effect of
    dieldrin in mice of high and low liver tumour susceptibility, with
    parallel metabolic studies, might provide a basis for relating
    observations of tumourogenicity in mice to other species, including
    man. There are at present no experimental data referable to

    Continued surveillance of persons occupationally exposed to dieldrin
    for chronic toxic effects and manifestation of possible
    carcinogenicity is recommended. In this connection, the extensive
    surveillance of occupationally exposed workers, which is currently
    being made, was noted.

    Information on the varying patterns of metabolism in the mouse, sheep,
    rat, monkey and man are as yet too incomplete to indicate whether the
    possible carcinogenic potential in the mouse is likely to apply to

    For these reasons, it was felt that no change in the acceptable daily
    intake established at the 1966 Joint Meeting could be made at this


    Level causing no toxicological effect

    Rat:  0.5 ppm in the diet, equivalent to 0.025 mg/kg body-weight/day.

    Dog:  1 ppm in the diet, equivalent to 0.025 mg/kg body-weight/day.


    0-0.0001 mg/kg body-weight, the sum of aldrin and dieldrin by weight.



    Seed treatments

    The use of aldrin and dieldrin as a rice seed treatment is now
    considered important only in Brazil and to a lesser degree in Japan,
    Costa Rica and El Salvador. The choice between aldrin and dieldrin is
    primarily a question of agronomic factors, local preference and
    economics prevailing. Treatment rates vary, but a rate of 2 oz /
    bushel (0.2 percent active material) is standard. In Brazil, recent
    figures show that out of 4,600,000 hectares planted, 3,680,000
    hectares (80 percent) were treated; in Japan, out of 3,280,000
    hectares planted, 169,000 hectares (0.5 percent) were treated; in
    Costa Rica, out of 43,000 hectares planted, 21,500 hectares (50
    percent) were treated and in El Salvador out of 31,000 hectares
    planted, 6,200 hectares (20 percent) were treated.


    In maize

    The treatment of soils prior to planting maize represents the most
    important of all uses for aldrin. Studies in the United States in
    which aldrin was applied to soil at rates of 1, 2, 3, 4 and 6 lb /acre
    and in which pre-harvest intervals ranged from 75-195 days resulted in
    aldrin residues in maize grain ranging from <0.001-<0.01 ppm and
    dieldrin residues from 0.002-0.02 ppm. Control values were equal to or
    greater than treated values in virtually all cases. In the same
    experiments, the corresponding residues of aldrin plus dieldrin in
    green fodder were less than 0.034 ppm; in maize stover most levels
    were less than 0.01 ppm and only in two subsamples did levels exceed
    0.03 ppm. With rare exceptions, the totals for aldrin and dieldrin
    fell well below 0.03 ppm (Shell Development Co., Reports RES 63-122,
    64-135, 64-102, 63-111, 64-168, 64-166 Shell Chemical Co., Reports PRL
    67-81, 67-62, 65-6, 67-92; Mourbry and Myrdal, pre-print
    communication). Similar experiments in Germany, France, Spain,
    Portugal, Australia, Mexico, Venezuela and Trinidad at application
    rates of 1-5 kg/ha gave residues of aldrin plus dieldrin of <0.01 ppm
    in maize grain; a second crop from treatment two years in succession
    gave the same result. Residues in whole maize plants (green fodder) in
    France, Spain, Australia and Trinidad were 0.01-ppm or less except for
    one year samples from Trinidad which were 0.15 ppm. This appears to be
    exceptional, since samples in the succeeding year were <0.01 ppm.
    Limited data from France on residues in maize leaves ranged from
    0.01-0.07 ppm in dry leaf. Based on this data, it is estimated that

    whole stover would have residues less than 0.03 ppm. (Shell Research
    Ltd., Reports WKGR 0114.70, 0053.68, ibid - unreported data). In the
    U.S.A. extensive data have been obtained for maize grown in a series
    of rotations typically employed in U.S. farm practice. Treatments were
    between 1´-2´ lb/acre - occasionally 5 lb/acre - and covered 35 sites
    and included two-eleven years. In no cases were residues detected in
    grain (0.01 ppm dieldrin). In stover, 80 percent of the results were
    below 0.01 ppm, and the upper limit was 0.02 ppm. No residues were
    detected in green corn (Shell Chemical Co., Report PRL 66-73).

    In potatoes

    The treatment of potato soils at recommended rates (2-4 kg/ha) with
    aldrin shortly before planting gave rise to residues in the whole
    washed tubers of between <0.01 ppm and 0.1 ppm of aldrin plus
    dieldrin. Typically, levels were 0.04-0.06 ppm. Levels in peeled
    tubers were generally 1/3-´ of these values (Shell International
    Chemical Co. Monograph, November 1968). More recent data developed by
    Shell in summarized in Table III; data from Scandinavia is given in
    Table IV.

    Residues in potatoes resulting from two or three soil applications of
    aldrin in consecutive years are summarized in Table V.

    A trial in Portugal compared residues resulting from broadcast
    applications with row applications made with aldrinised fertilizer,
    all at 3 kg/ha. Results are shown in Table VI (Shell Research Ltd.,
    Tech. Serv. Report WKTR.0025/69).

    Potatoes were planted in plots in tropical countries from which maize,
    grown on soil treated at 2-4 kg/ha just prior to sowing, had been
    harvested. Aldrin + dieldrin residues in the tubers were from <0.01
    to 0.07 ppm (mean--0.03 ppm) and in peeled tubers from <0.01 to 0.03
    ppm (mean--0.01 ppm), as shown in Table VI (Shell Research Ltd.,
    Report WKGR. 0114.70).

    Residue data for potatoes grown in soils in temperate countries to
    which aldrin treatment had been given one or two years before planting
    are given in Table VII.

    Analytical data for 256 samples of peeled potatoes and potato peel
    obtained by the U.K. Ministry of Agriculture (Lee, 1968) from potatoes
    grown commercially on treated (three or four lb./acre) land shows
    residues of aldrin plus dieldrin in peeled tubers ranging from
    0.0-0.14 ppm (mean--0.01 ppm). Calculated residues in whole tubers
    based on 15 percent peel ranged from 0.0 to 0.23 ppm (mean--ca. 0.02

    In sugar beets, juice and pulp

    Residues of aldrin plus dieldrin in sugar beets grown in soils treated
    once with 2 kg/ha in the same year as cropping ranged from <0.01 to
    0.03 ppm; 4 kg/ha resulted in residues ranging from <0.01 to 0.05 ppm

    (Legar, 1966; van Steyvoort et al., 1968; Shell Research Ltd., Reports
    WKTR.0053.68, WKGR.0123.69, WKGR.0114.70; Shell Chemical Co., Report
    PRL-68-148). In contradiction to all these findings, Walker et al.,
    (1965) found that one application of 5 lb./acre gave combined residues
    in the whole fresh beet of 0.19 ppm and Smith et al., (1966) found
    residues of 0.93 ppm resulted from 1 lb./acre of aldrin as a row
    application at the time of sowing. However, 80 percent of this latter
    residue occurred as aldrin, strongly indicating sample contamination.
    Residues of dieldrin in sugar beet tops from beets grown in soils
    treated once with aldrin at 1-6 kg/ha in various countries in Europe
    and in Turkey ranged from <0.001 to 0.01 ppm (van Steyvoort et al.,
    1968; Shell Research Ltd., Reports WKTR. 0053.68, WKGR.0123.69,
    .0114.70). Residues of aldrin plus dieldrin in roots and tops of sugar
    beets grown in soils treated two and sometimes three years in
    succession are summarized in Table VIII.

        Table III

    Residues in potatoes arising from soil applications of aldrin


    Application  Range of Values, ppm       No. of Results   Arithmetic Mean

    Rate         Whole         Peeled       Whole   Pooled   Whole    Peeled
    kg/ha        Tubers        Tubers       Tubers  Tubers   Tubers   Tubers

    2            <0.01-0.13    <0.01-0.05   24      10       0.06     0.02

    3            0.01-0.16     -            18      -        0.08     -

    4            0.03-0.24     0.01-0.07    10      10       0.11     0.04

    2-4          <0.01-0.24    -            52      -        0.08     -

    5            0.02-0.22     -            11      -        0.11     -

    Shell Chemical Co., Reports PRL 68-147, PCY-64-10; Shell Research Ltd.,
    Reports WKTR. 0025/69, Tech. Memo 137/65, Tech. Serv. Note 141/66,
    WKTR. 0114. 70; Winnett and Reed, 1968.

    Table IV

    Aldrin and Dieldrin Residues in Potatoes Arising from single soil
    applications in Scandinavia


                   Application          Residues, ppm in
                   Rate,                  potato tubers
    Country        kg/ha         Aldrin       Dieldrin     Reference

    Sweden(1964)   2.5           <0.01        0.02

    Sweden(1965)   2.5           <0.01-0.01   <0.01-0.02   Renvall and
                                                           Akerblom, (1968)

    Sweden(1966)   2.5           <0.01        0.01

                   2.5           <0.01        0.05

                   2.5           0.01         0.02

                   2.5           0.02         0.13

                   2.5           0.03         0.12

    Denmark        2.5           not found    0.05         Bro-Rasmussen
                   5.0*          not found    0.02-0.05    and Voldum-

                   10.0*         0.02         0.03-0.10    Clausen, (1966)

    *  High rates

    Table V

    Aldrin plus dieldrin residnes in potatoes grown in plots which received
    a number of annual treatments with aIdrin


                  Range of values
    Application   Aldrin + Dieldrin,                         Arithmetic
    kg/ha                ppm               No. of results    Mean, ppm
                  Whole      Peeled        Whole   Peeled    Whole    Peeled

    2             0.01-0.11  00.01-0-05    11      8         0.05     0.02

    4             0.03-0.40  <0.01-0.01    8       8         0.14     0.03

    Shell Research Ltd., Reports WKTR-0007.69, 0028.68, Tech. Serv. Note
    141/66, Report WKGR.0114.70, 0153/69, Tech. Serv. Note WKTR. 0100.68.

    Table VI

    Comparison of residues in potato tubers from broadcast and
    row treatments


                          Range of Results,
    Type of               Aldrin + Dieldrin,     No. of      Arithmetic
    Application           ppm                    Values      Mean, ppm

    Row treatment         0.09-0.27              4           0.15

    Broadcast             0.04-0.07              3           0.05

    Broadcast (E.C.)      0.05-0.16              4           0.08

    Table VII

    Residues In potato tubers grown-in soils treated one or two years
    prior to planting


    Treatment    Between          Range of
    Rate,        Treatment and    Results,         No. of      Arithmetic
    kg/ha        Planting,        ppm              Results     Mean, ppm

    2            1                <0.01-0.05       14          0.02

    4            1                0.01-0.05        9           0.03

    2-5          1                <0.01-0.11       29          0.04

    2-5          2                0.01-0.02        12          0.01

    Shell Research Ltd., Tech. Serv. Note 141/66, Report WKGR.0114.70,
    Tech. Serv. Report WKTR 0007.69, .0028.68, Report WKGR 0153/69,
    Tech. Serv. Note WKTR.0100.68, Winnett and Reed; 1968.
    Residues of dieldrin in roots and tops of beets grown on plots treated
    the previous year at 2 or 4 kg/ha were all <0.01 ppm (28 samples)
    except for two root samples of 0.02 and 0.03 ppm; no aldrin was
    detected (Elgar, 1966; Shell Research Ltd., Report WKGR.0114.70).

    Recent studies by Onsager at al., (1970) show that aldrin plus
    dieldrin residues in mature sugar beets are proportional to the
    residues in the soil at the time of planting as illustrated in Table

    Studies in Belgium (van Steyvoort et al., 1968) and in France (Shell
    Research Ltd., Report WKTR.0053.68) indicate that no residues could be
    found in purified juices from sugar beets grown in soil treated with
    up to 6 kg/ha of aldrin. However, data from refineries in the U.S.A.
    (Walker at al., 1965) show combined residues of 0.02 ppm (expressed as
    ppm of pure sucrose) in clarified juice from beets with abnormally
    high residue levels. Had these juices been processed, most of the
    residue would have been found in the molasses rather than in the

    Data was obtained on dieldrin residues in dried pulp from beets grown
    in soil which had received aldrin treatment for two years preceding
    planting. A residue of 0.03 ppm in the fresh beet resulted in values
    of 0.13-0.14 ppm in pulp dried at 105°C and 0.05-0.12 in pulp dried at
    150°C; 0.07 ppm in fresh beet gave values of 0.28 ppm in pulp dried at
    105°C and 0.34 ppm in pulp dried at 150°C (Shell Research Ltd.,
    unreported data). The ratio of residues in dried pulp to fresh beet
    was 3-4 which is lower than the figure of 10.6 reported by Walker et
    al. (1965). The significance of pulp residues in terms of cattle feed
    is questionable, however, due to the low amount of pulp (10-20
    percent) in the total diet. Onsager et al. (1970) calculated that a
    residue of 0.25 ppm in 4.5-8 lb of beet pulp fed daily to a 1200-lb
    animal amounts to ingestion of 0.2-1.6 ppm of insecticide. 

    In crops derived from seed dressings

    Both aldrin and dieldrin are extensively used as seed dressings on a
    wide variety of crops; maize, rice, cereals, cotton and pulse crops
    are the most important. A large amount of data collected primarily by
    Shell shows that residues in the crop derived from dressed seed are
    extremely small and usually below the limits of detection (about 0.005
    ppm), except for occasional residues of 0.01-0.02 ppm in pulse crops.
    In all cases where residues were much above the detection limit, there
    are strong indications that samples were contaminated. Either residues
    were high on control as well as treated samples, or else appreciable
    proportions of aldrin were found in the total residue.

    In vegetables

    Residue data obtained up through 1968 is summarized in Table X (Shell
    International Chemical Co., Monograph, Residues in Vegetables,
    November 1968).

        Table VIII

    Residues in sugar beets grown in soils treated on more than one occasion

    Rate of
    Application,                Range of Residues                 Arithmetic
    kg/ha/           Part of    Aldrin + Dieldrin,    No. of      Mean,
    year             Crop       ppm                   Samples     ppm

    2                Root       <0.01-0.04            8           0.01

    4                Root       <0.01-0.07            5           0.04

    2                Tops       <0.01-0.02            5           <0.01

    4                Tops       <0.01-0.02            5           <0.01

    Table IX

    Average residues of aldrin plus dieldrin in soil and sugar beet roots

                             Average residue, ppm
    Aldrin         Soil
    dosage,        sampled on               Roots sampled on
    lb ai/acre     4/10/65        10/5/65        10/25/66       10/17/67

    0.625          0.05           <0.01          <0.01          <0.01

    1.25           0.21           0.04           <0.01          <0.01

    2.5            0.38           0.06           0.01           0.01

    5.0            0.73           0.13           0.02           0.01

    7.5            1.84           0.37           0.03           0.03

    10.0           2.84           0.96           0.05           0.04

    Table X

    Residues from seed or soil treatment with aldrin and dieldrin at
    application rates within the recommended range (typically 2-3 kg/ha).

    Crop or                Residues, ppm               Location and
    Crop Group       Min       Max     Est. Median     No. of Expts.

    Carrots          0.02      0.51    0.20            USA:3, Switzerland:5,
                                                       Denmark:2, Holland, 3,
                                                       UK:3, Austria:2

    Cruciferous      0.02      0.08    0.04            USA:20, Norway:1,
    roots (1)                                          Austria:2

    Beetroot         0.01      0.22    0.10            USA:15

    Cole crops (2)   0.01      0.02    0.015           USA:21

    Onions           ND        ND      ND              UK:3, USA:1

    Peas             ND        ND      ND              USA:1

    Lettuce          0.10      0.16    -               USA:2

    Beans            ND        ND      ND              USA:3

    Tomatoes         0.10      0.10    0.10            USA:3

    Celery           0.02      ND      ND              UK:3

    Cucurbits (3)    0.01      0.07    0.03            USA:10

    (1)  Including radish, turnip, rutabaga and swede.
    (2)  Including cabbage broccoli, brussels sprouts and cauliflower.
    (3)  Including cucumber, pumpkin and melon.
    More recent data on beetroot, cauliflower, carrots, white cabbage,
    lettuce, tomatoes, turnips, and sweet potatoes are consistent with the
    findings in Table X and in general give slightly lower residue figures
    (Bro-Rasmussen and Voldum-Clausen, 1966; Shell Research Ltd., Reports
    WKTR. 0050.68, 0053.68; Shell Chemical Co., Reports PRL-68-112,

    In cereal grain

    Aldrin treatments of seed or soil at recommended rates have rarely
    produced residues of aldrin plus dieldrin in grain of wheat, oats or
    barley above 0.01 ppm. Foliar applications of aldrin or dieldrin to
    the growing crop do not give measurable residues in grain or straw if
    pre-harvest intervals of one month or more are observed (Shell
    International Chemical Co., Monograph, Residues in Small Grains,

    Recent data for wheat and barley grain from soils receiving a variety
    of aldrin application regimes at rates of 2 or 4 kg/ha show no
    detectable residues (<0.01 ppm) of either aldrin or dieldrin.
    Residues in wheat straw ranged from <0.01-0.16 ppm and in barley
    straw from <0.01-0.20 ppm. Straw residues are of limited significance
    since wheat straw is not an appreciable component in the diet of dairy
    cattle and barley straw is used as a feed primarily for beef cattle in
    winter only (Shell Research Ltd., Reports WKGR.0114.70, WKTR-0053.68).

    In citrus and sugar-cane

    Soil applications of aldrin at 2.0-5.0 kg/ha in citrus groves resulted
    in dieldrin residues of 0.01-0.02 ppm in whole oranges, 0.02 ppm in
    chopped peel and 0.03-0.04 ppm in dried pulp; controls contained up to
    0.01 ppm. Dieldrin residues were not found in whole grapefruit or
    grapefruit juice, but peel contained 0.006-0.007 ppm and dried pulp
    contained 0.01 ppm; residues were also found in control samples (Shell
    Chemical Co., Report PRL-67-30).

    No residues were found in any of six samples of sugar-cane grown in
    soil treated with two applications of aldrin at 2 kg/ha (Shell
    Chemical Co., Report PRL-68-51). Soil treatments with aldrin of 5 or
    10 lb ai/acre resulted in apparent aldrin residues of 0.004 ppm in two
    out of three foliage samples from the 10 lb/acre treatment and in
    apparent dieldrin residues ranging from 0.008-0.015 ppm in 8 out of 16
    samples of foliage and stalks. No residues were found in the juice at
    any treatment rate, and one sample of bagasse (out of four) had 0.009
    ppm dieldrin (Shell Chemical Co., Report PRL-68-236).

    In milk and meat (from cattle feed)

    Williams et al. (1964) fed 16 milking cows for 35 days with a feed
    containing various amounts of dieldrin. Similar experiments were
    carried out by Gannon et al. (1959a, 1959b) for 12 weeks and by Shell
    (1970) for 21 days using dieldrin C-14. The results of these
    investigations are summarized in Table XI.

    After the feeding of dieldrin was stopped, dieldrin concentrations in
    the milk began to fall with a half-life of 10-15 days in the case of
    Williams' work and substantially longer in the case of Gannon's work.
    The lack of consistency may be due to some cows coming to the end of
    their lactation period, thus reducing the milk production per day.

    Gannon et al. (1959a) also studied residues in body tissues of milk
    cows and steers fed diets containing various amounts of dieldrin. His
    results are shown in Table XII.

    In poultry and eggs

    The residues of dieldrin that could arise in poultry products from the
    use of rice bran in the diet (typically 20 percent of the total diet)
    are summarized in Table XIII.

    Thus with residues of dieldrin in rice bran of 0.05 ppm, residues of
    dieldrin in poultry products could be 0.012 ppm in eggs, 0.20 ppm in
    fat and 0.02 ppm in poultry meat. Residues of up to 0.03 ppm dieldrin
    are commonly found in rice bran.


    General comments

    The occurrence and toxicity of the photoisomer of dieldrin,
    photodieldrin, has been reviewed in the section on biological studies.
    Photodieldrin residues may be of significance only after foliar
    application of dieldrin. No detectable residues were found in human
    fat in the U.S.A. where the ratio of dieldrin to photodieldrin
    residues was greater than 200 to 1 (Richardson, 1966). Photodieldrin
    was also absent in human fat from U.K. and Holland (Richardson, 1968)
    and milk (Robinson et al., 1966).

    In animals

    The fate of residues of dieldrin in animals has been covered under the
    biochemical section of this monograph.

    In plants

    Extensive experimental work was carried out by Shell to determine
    residues of photoaldrin and photodieldrin in crops grown on
    aldrin-treated soil, grown from aldrin or dieldrin-treated seed, grown
    in soils containing old residues or receiving foliar applications of
    dieldrin, and general monitoring investigations. Their results
    indicate that none of the soil or seed dressing uses of aldrin or
    dieldrin lead to detectable residues of the photoisomers. Foliar
    applications led to photodieldrin residues of 0.03 ppm in coffee beans
    treated at 1-1/3 g of dieldrin/ tree, 0.02 ppm in leaves of forage
    beets treated at 4.3 oz/acre, 0.31-0.89 ppm in wheat straw treated at
    8 oz /acre, <0.01-0.04 ppm in apples and 0.01-0.06 ppm in apple
    pomace treated at ´ lb/acre, 3.6 ppm in pasture grass one and a half
    months after treatment with 1 oz/acre, and 1.1 ppm in fat of sheep
    grazing for four months on the treated pasture grass. None of the
    photoisomer was detected in any samples of vegetable oils and fats
    monitored in the U.K., but some samples of food and feed components
    contained traces.

        Table XI

    Dieldrin in milk from animals fed with feed containing
    different amounts and for various lengths of time

    Dieldrin in                                  Butterfat                Ratio,
    feed, ppm,          Milk level, ppm,         equivalent, ppm,         ppm B.F.
    dry weight          at time indicated        at time indicated        ppm Feed            Reference

                        35 days                  35 day

    0                   0.004                    0.11                     -                   Williams
    0.09                0.021                    0.53                     5.9                 et al.
    0.23                0.058                    1.52                     6.6                 (1964)
    0.50                0.11                     2.89                     5.9

                        4 weeks    12 weeks      4 weeks    12 weeks

    0                   <0.01      0.01          -          -             -                   Gannon
    0.1                 <0.01      0.02          -          0.5           5.0                 et al.
    0.25                0.02       0.06          0.5        1.5           6.0                 (1959b)
    0.75                0.07       0.11          1.75       2.8           3.1
    2.25                0.16       0.28          4.0        7.0           3.0

                        15-21 days               15-21 days

    0.102               0.018                    0.41                     4.0                 Shell
    0.120               0.017                    0.35                     2.9                 Development
    0.111               0.015                    0.38                     3.5                 Co., Report

    Table XII

    Dieldrin residues in body tissues of cows and steers after feeding at
    various levels of dieldrin for twelve weeks


                   Milk cows                 Steers

                   Dieldrin in Feed, ppm        Dieldrin in Feed, ppm
    Body Part      0.25             2.25     0.1    0.25     0.75    2.25

                                    Dieldrin in Tissues, ppm

    Brain          <0.1             0.1      -      -        -       -

    Heart          0.2              0.6      -      -        -       -

    Liver          0.2              0.7      -      0.1      -       0.7

    Kidney         <0.1             <0.1     -      <0.1     -       0.2

    Steak          0.1              1.3      -      <0.1     -       1.0

    Roast          0.2              1.2      -      -        -       -

    Renal Fat      0.9              6.2      -      0.9      -       9.7

    Body Fat       0.9              4.8      0.4    0.8      3.5     8.7

    Heart Fat      -                7.0      -      -        -       -

    Udder Fat      -                5.6      -      -        -       -

    The average ratio of dieldrin levels in fat to levels in feed was 2.75
    in milk cows and 3.95 in steers.

    Table XIII

    Relation between dieldrin residues in poultry feed
    and poultry products (eggs, meat, fat of meat)


                                   Feed              Range of Ratios,
    Poultry             Weeks      Concentration     Poultry Feed/
    Product             fed        Range (ppm)       Poultry Product      Reference

    Eggs                12         0.1-0.75          0.8-1.6              Gannon et al., 1959a

    Eggs                16         0.006-5.0         1.0-3.0*             Greaves et al., 1969a

    Eggs                14         0.05-0.45         1.1-1.2              Cummings et al., 1966

    Fat(abdominal)      2          0.1-0.15          20-29                Liska et al., 1967

    Fat                 12         0.1-0.75          41-48                Gannon et al., 1959a

    Fat(abdominal)      14         0.05-0.45         8.8-9.7              Cummings et al., 1967

    Meat                2          0.1-0.15          2-4                  Liska et al., 1967

    Meat                12         0.1-0.75          <0.2                 Gannon et al., 1959a

    Meat                14         0.05-0.45         0.1                  Cummings et al., 1967

    *  The figure of 3 regarded as inconsistent with other data.

    Lichtenstein et al. (1970) reported 0.015 ppm photodieldrin in soils
    which had been treated annually with 5 lb/acre of aldrin for five
    years and then not treated for five years. Potatoes and carrots grown
    in these soils contained 0.0006 ppm and 0.002 ppm, respectively.

    After foliar application of photodieldrin C-14 to white cabbage,
    residues disappeared more slowly than in corresponding tests with
    aldrin, dieldrin, isodrin or endrin. Four weeks after application, as
    much as 75 percent of the applied radioactivity was present as
    residues. Fifteen to 33 percent of metabolites were found mainly in
    leaves. Metabolic fractions consisted of a very hydrophilic main
    product and at least two less hydrophilic by-products (Korte and
    Porter, 1970).

    Four weeks after application of ca. 75 ppm of aldrin C-14 on the upper
    side of cabbage leaves, only 17 percent of the applied radioactivity
    was recovered in plants and soil. Hydrophilic metabolites made up 76
    percent of the recovered activity; besides aldrin, five other
    compounds were found, one of which appeared to be dieldrin. In similar
    experiments with dieldrin C-14 on cabbage, 40 percent of the
    radioactivity is recovered after four weeks and 34 percent of the
    recovered activity is due to at least two hydrophilic metabolites
    (Korte, 1970).

    In soils

    Maize grown in California in soil treated with 3 kg/ha of aldrin C-14
    contained no detectable C-14 in the grain or cobs. The husks of the
    ears contained 0.004 ppm aldrin, 0.004 ppm dieldrin and 0.032 ppm
    metabolites. The leaves contained 0.35 ppm C-14 equivalents of which
    0.02 ppm was aldrin and 0.05 ppm was dieldrin (Korte and Porter,

    Evidence of residues in food in commerce


    Thirty local and sixteen imported samples of butter were examined
    (Dejaukheere and Kips, 1968). In the local samples, residues of
    dieldrin ranged from 0.01 to 0.24 ppm (mean 0.12 ppm), and in the
    imported samples the range was 0.01 to 0.25 ppm.


    Samples of milk butterfat (44) contained mean levels of dieldrin of
    0.03 ppm (<0.007-0.11) (Bro-Rasmussen et al., 1968). Samples of
    butter examined over a three year period contained dieldrin residues
    as follows:

                          1964                    1965                 1966

    No. of samples        118                     137                  126

    Range (ppm)        0.01-0.20               0.01-0.18            0.01-0.17

    Mean (ppm)            0.05                    0.04                 0.03

    The authors suggested from their data that 60-100 percent of these
    residues originated from dieldrin residues in imported cattle feed.


    Mestres, et al., (1967) in France found no residue of aldrin or
    dieldrin in 44 samples of French butter or in four samples of Swiss
    butter at a detection limit of 0.02 ppm.

    West Germany

    Of 65 samples of carrots taken in West Germany (Maier-Bode, 1967) 43
    contained less than 0.01 ppm aldrin plus dieldrin. Of the remainder,
    64 percent contained residues of 0.03 ppm or less, and only one sample
    exceeded 0.1 ppm (0.17 ppm).


    Twenty butter samples out of a total of 54 contained dieldrin residues
    in the range 0.01-0.1 ppm (Sakshaug, 1968). The rest did not contain
    residues, above the limit of detection.


    Routine analysis of food-stuffs by public analysts in the U.K. (Rymer
    and Hammence, 1967) demonstrated that of 776 fruit, 461 vegetable and
    237 meat and dairy produce samples, only three fruit samples and three
    meat and dairy produce samples contained aldrin above the limits of
    detection (maximum levels of 0.06 and 0.18 ppm respectively) and two
    fruit, one vegetable and thirteen produce samples contained dieldrin
    above the limits of detection (maximum 0.15 and 0.27 ppm).

    A more recent examination of 388 fruit, 285 vegetable and 217 meat and
    dairy produce samples (Dickes and Nicholas, 1969) revealed one
    vegetable sample containing aldrin (0.09 ppm) and sixteen vegetable
    samples containing dieldrin, although all were below 0.01 ppm.

    Findlay and Hamilton (1968) examined 163 samples of eggs and 114
    samples of poultry meat, liver and fat from nine sources within the
    U.K. No egg samples exceeded 0.06 ppm of dieldrin and only one poultry
    meat sample exceeded 0.1 ppm (0.13 ppm).

        Table XIV

    Dieldrin residues in dairy and meat products produced in U.K., 1965-1968

                   Butter              Milk               Mutton Fat              Beef Fat
    Year                Mean                Mean                   Mean                  Mean
              Samples   (ppm)     Samples   (ppm)       Samples    (ppm)      Samples    (ppm)

    1964                                                127        0.84

    1965      18        0.03      85        0.0025      107        1.15       59         0.06

    1966      13        0.02      75        0.0025      101        0.44       63         0.04

    1967      22        0.03      77        0.002       76         0.24       36         0.03

    1968      16        0.03      76        0.001       77         0.21       34         0.03

    A most comprehensive examination of home produced and imported meat
    and dairy products has been carried out over a number of years by the
    Laboratory of the Government Chemist (1966, 1967, 1968, 1969). In the
    four years 1965-1968, 935 samples of home produced foods and 803
    samples of foods imported from ten countries were analyzed. Table XIV
    summarizes their findings for home-produced dairy and meat products.

    Residues in food at time of consumption

    A study of data accumulated over four years by the U.S. Food and Drug
    Administration on pesticide residues in total diet samples was made by
    Duggan and Lipscomb (1969).

    Residues of dieldrin were found in from 15.6-21.3 percent of
    composites analyzed over this period and aldrin residues were found in
    from 3.3-5.6 percent. Measurable dieldrin residues were present in six
    of the twelve food groups examined, and traces were found in another
    four. Measurable aldrin residues were found in only one group. The
    highest residues of dieldrin (max. 0.20 ppm) were found in samples of
    meat, fish and poultry (Group 2). In the dairy products group (Group
    1) the greatest level was 0.08 ppm and residues did not exceed 0.03
    ppm in any other group. The maximum aldrin level was 0.07 ppm in the
    first group (Group 9). No tendency to increase or decrease was
    observed over this period. From the residue information and a
    knowledge of the diet, the daily intake of each pesticide was
    calculated. Since the diet was representative of that consumed by a
    sixteen-nineteen year old American male, the intake of the average
    population will be about half the calculated figure. The total daily
    intake for aldrin and dieldrin over the four year period is given in
    the following table (from Duggan and Lipscomb, 1969):

    Daily Intake (mg/kg body-weight)


                   1965           1966           1967           1968

    Aldrin         0.00001        0.00004        0.00001        0.00001

    Dieldrin       0.00008        0.00009        0.00005        0.00005

    Total          0.00009        0.00013        0.00006        0.00006

    An examination of residues in groups of foodstuffs making up a
    complete diet was undertaken by Abbott et al., (1969), at the
    instigation of the U.K. Ministry of Agriculture, Fisheries and Food,
    for one year from October 1966-October 1967. Of the foods analyzed,
    the highest dieldrin residues were in fat (mean 0.024 ppm, range
    0.009-0.075 ppm), followed by meat (mean 0.009 ppm, range 0.001-0.060
    ppm). Because of the larger consumption of meat, this group provides

    the largest intake of dieldrin 2.2 mg/person/day. The mean daily
    intake in the diet calculated from the residues found was 0.00009
    mg/kg body-weight. This figure confirms the decrease shown in the
    second survey by McGill and Robinson (1968) compared with the first,
    and may be attributed to the voluntary withdrawal of some previously
    approved dieldrin uses in the U.K. over the period 1965-1967.

    In 1965 the Association of Public Analysts prepared a survey to
    determine the extent of contamination of foodstuffs by pesticides.
    Data for the first year of this work has so far been reported
    (Association of Public Analysts, 1969). Of the 2352 samples analyzed,
    only ten contained residues of aldrin (two only above 0.1 ppm) and 76
    contained dieldrin (again only two above 0.1 ppm). Dieldrin was most
    commonly found in meat and dairy products. In no foodstuffs did the
    mean level of dieldrin residues exceed 0.015 ppm, a figure that is
    based on the assumption that all samples in which residues were not
    detected (limit 0.002 ppm in solid foods and 0.0002 ppm in liquid milk
    and infant foods) did in fact contain residues at half the detection
    limit. Using the same assumption, the mean daily intake in the diet
    was calculated to be 0.0001 mg/kg body-weight. A survey of residues in
    welfare foods (dried full cream milk, cod-liver oil and concentrated
    orange juice) by Ruzicka et al., (1967) revealed residues of up to
    0.017 ppm dieldrin (mean 0.011 ppm) in dried milk and demonstrated a
    15 percent loss in residue during the drying period. Cod-liver oil
    contained 0.15-0.20 ppm (mean 0.16 ppm) and concentrated orange juice
    contained up to 0.007 ppm (mean 0.002 ppm).


    The remarks on methods for residues of organochlorine pesticides and
    multidetection systems of analysis (FAO/WHO, 1967a) apply to the
    determination of aldrin and dieldrin. Burke (1969) has studied the
    application of the official AOAC multiresidue method to photodieldrin.
    No methods of analysis have been well worked out for the more
    hydrophilic metabolites of dieldrin such as monohydroxydieldrin,
    dihydro-aldrin-diol (trans), dieldrin-ketone, dieldrin-ketone
    photo-isomer, or Klein's metabolite. Although photoaldrin can be
    determined by GLC techniques, the rapid conversion of aldrin to
    dieldrin makes it unlikely that photoaldrin will be a significant
    residue in crops or soils.


    The meeting considered three questions arising from the Draft Report
    of the Fifth Session of the Codex Committee in 1970 as follows:

    Further data on the use pattern of aldrin and dieldrin on rice are
    provided in this monograph, as are data on residues resulting from the
    use in animal feed.

    The question of the fate of the residues on rice during processing was
    not considered because the available data show that residues are so
    small that any remaining following processing would be negligible.

    No firm data were received on residues in fruit juices resulting from
    the use of rice husks as clarifying agents. However, if it is assumed
    that 10 percent rice husks are used for clarification, and if they
    should contain up to 0.02 ppm of aldrin plus dieldrin, and if it is
    further assumed that this is extracted by the fruit juices (unlikely
    due to the lipophylic nature of residues), then it would be highly
    improbable that residues in excess of 0.002 ppm in the juice would


    The data provided on residues of aldrin plus dieldrin in maize grain
    resulting from planting maize in soils treated at recommended rates
    indicate that levels of 0.02 ppm or less could be expected and that
    maize grain is within the recommended practical residue limit of 0.02
    ppm on raw cereals listed in the 1969 Report of the Joint Meeting.

    The data on residues of aldrin plus dieldrin in whole washed potato
    tubers arising from soil applications of aldrin at recommended rates
    reveals the possibility of exceeding the recommended tolerance of 0.1
    ppm, especially when the potatoes are grown in plots receiving a
    number of annual applications at the highest rate. An increased
    tolerance of 0.2 ppm is recommended for potatoes.

    Residues of aldrin plus dieldrin in mature sugar beets are
    proportional to the residues in soil at planting. For example, an
    aldrin dosage of 2.5 lb/acre gives after six months a soil residue of
    0.11 ppm and a sugar beet root residue, grown in the same year, of
    0.06 ppm. This would be expected to result in about 0.24 ppm of
    dieldrin residue in the pulp dried at 105°C. This amount of residue
    under normal feeding practices would not lead to excessive residues in
    whole milk or meat (fat basis). Therefore, the recommended practical
    residue limits appear to be adequate for residues from this source.

    Residues in the crop derived from dressed seed (maize, rice, cereals,
    cotton and pulse crops) are extremely small and usually below the
    limits of detection, thus justifying the reduction of the tolerance in
    rough rice to 0.02 ppm.

    Residues in vegetables from seed or soil treatment are dependent on
    the type of crop. Residues at or in excess of tolerance could arise in
    carrots and lettuce planted in soil previously treated for other
    crops. Data were received which justify a revision of the recommended
    tolerance and the establishment of a practical residue limit of 0.2
    ppm for lettuce and carrots.

    Soil applications of aldrin of 2-5 kg/ha in citrus groves resulted in
    dieldrin residues of 0.01-0.02 ppm in whole oranges and no detectable
    residues in grapefruit. The presently recommended tolerance of 0.05
    ppm appears to be adequate.

    The importance of photodieldrin as a plant metabolite of aldrin or
    dieldrin appears to be well established; however, its significance as
    a terminal residue will depend on the results of experiments in
    progress on rates of storage and excretion in animals.

    A consideration of the new data supplied on residues in milk, milk
    products and meat resulting from supervised trials and surveys of food
    in commerce does not indicate a need for revision of the previously
    recommended practical residue limits for these items at this time. The
    previous practical residue limit of 0.125 ppm for milk products was
    changed to 0.15 ppm to allow for the limitations and variability of
    residue analytical procedures.

    A suitable regulatory method of analysis exists for photodieldrin
    (official AOAC multiresidue method) but no methods of analysis have
    been worked out for the more hydrophilic metabolites of dieldrin.


    The previously recommended tolerances and practical residue limits (no
    longer temporary) are amended as follows:


    Fruit (other than citrus), asparagus,
    broccoli, brussels sprouts, cabbage,
    cauliflower, cucumber, eggplant,
    horse-radish, onions, parsnips, peppers,
    pimentoes, radishes and radish tops                             0.1

    Citrus                                                          0.05

    Rice (rough)                                                    0.02

    Potatoes                                                        0.2



    Carrots, lettuce, fat of meat                                   0.2

    Raw cereals (other than rice)                                   0.02

    Milk and milk products (fat basis)                              0.15

    Eggs (shell-free)                                               0.1



    1. Further information relevant to the assessment of the significance
    of the changes that occur in the livers of mice exposed to dieldrin. A
    comparison of the response to dieldrin of high and low spontaneous
    liver-tumour mouse strains in respect of liver tumour incidence and
    the metabolism of dieldrin might be helpful in this respect.

    2. The continued collection of follow-up information on persons
    exposed occupationally in the manufacture of dieldrin.

    3. Completion of the studies being conducted on the comparative
    metabolism of dieldrin in man, monkey, rat and mouse.

    4. Experimental studies to determine whether dieldrin might have
    teratogenic potential.

    5. A continuing study of the possible occurrence of residues of
    photodieldrin in food surveys and total diet studies.


    Abbott, D.C., Holmes, D.C. and Tatton, J.O'G. (1969) Pesticide
    residues in the total diet in England and Wales, 1966-1967. J.Sci.Fd.
    Agric., 20: 245-249

    Association of Public Analysts, London. (1969) Joint survey of
    pesticide residues in foodstuffs sold in England and Wales, August
    1966-July 1967

    Baldwin, M.K. and Robinson, J. (1969a) The identification of a
    metabolite of the photo-isomerization product of HEOD (dieldrin) found
    in rat tissues. Unpublished report from the Tunstall Laboratory, Shell
    Research Ltd., Sittingbourne

    Baldwin, M.K. and Robinson, J. (1969b) Metabolism in the rat of the
    photo-isomerization product of dieldrin. Nature, 224: 283-284

    Baldwin, M.K. and Robinson, J. (1970) Comparison of the metabolism of
    HEOD in the CFI mouse with that in the CFE rat - preliminary results.
    Unpublished report from the Tunstall Laboratory, Shell Research Ltd.,

    Baldwin, M.K., Robinson, J. and Carrington, R.A.G. (1970) Metabolism
    of HEOD (dieldrin) in the rat: examination of the major faecal
    metabolite. Chem. Industr., 595-597

    Bick, M. (1967) Chlorinated hydrocarbon residues in human body fat.
    Med. J. Austr., 54 (1): 1127-1130

    Braund, D.G., Brown, L.D., Huber, J.J., Leeling, N.C. and Zabik, M.J.
    (1969) Excretion and storage of dieldrin in dairy cows fed
    thryoprotein and different levels of energy. J. Dairy Sci., 52:

    Brooks, G.T. (1969) The metabolism of diene-organochlorine
    (cyclodiene) insecticides. Res. Rev., 27: 81-138

    Bro-Rasmussen, F., and Voldum-Clausen, K. (1966) Tids. Planteovl.,
    20: 232

    Bro-Rasmussen, F., Dalgaard-Mikkelsen, S., Jakobsen T., Koch, S.O.,
    Rodin, F., Uhl, E. and Voldum-Clausen, K. (1968) Examinations of

    Danish milk and butter for contaminating organochlorine insecticides.
    Res. Rev., 23: 55-69

    Brown, V.K., Robinson, J. and Richardson, A. (1967) Preliminary
    studies on the acute and sub-acute toxicities of a photoisomerization
    products of HEOD (dieldrin). Unpublished report from the Tunstall
    Laboratory, Shell Research Ltd., Sittingbourne

    Chan, T. and Terriere, L.C. (1969) Aldrin epoxidase activity of rat
    liver and rat liver microsomes under various conditions of storage.
    Biochem. Pharmacol., 18: 1061-1070

    Cole, J.F., Klevay, L.M. and Zavon, M.R. (1970) Endrin and dieldrin: a
    comparison of hepatic excretion in the rat. Toxicol. appl. Pharmacol.,
    16: 547-555

    Crabtree, A.N. (1969) The concentrations of organochlorine
    insecticides in human fat and blood from Australia. Shell Research
    Limited, Tunstall Report No. TL GR. 0059.69

    Cummings, J.G., Zee, K.T., Turner, V. and Quinn, F. (1966) Residues in
    eggs from low level feeding of five chlorinated hydrocarbon
    insecticides to hens. J. Ass. Off. Anal. Chem., 49: 354-364

    Cummings, J.G., Gidelman M., Turner V., Reed D., Zee K.T. and Cook
    R.E. (1967) Residues in poultry tissues from low level feeding of five
    chlorinated hydrocarbon insecticides to hens. J. Ass. Off. Anal.
    Chem., 50: 418-425

    Dailey, R.E., Walton, M.S., Beck, V., Leavens, C.L. and Klein, A.K.
    (1970) Excretion, distribution and tissue storage of a 14C-labelled
    photoconversion product of 14C-dieldrin. J. Agr. Fd. Chem., 18:

    Damico, J.N., Chen, J.T., Costello, C.E. and Haenni, E.O. (1968)
    Structure of Klein's metabolites of aldrin and dieldrin. J. Ass. Off.
    agr. Chem., 51: 48-55

    Datta, P.R., Lang, E.P., Watts, J.O., Klein, A.K. and Nelson, M.J.
    (1965)  Metabolites in urine of rats on diets containing aldrin or
    dieldrin. Nature, 208: 289-290

    Dejaukheere, W. and Kips, R.N. (1968) Meded. Rijksfac.
    Landbouwwenteusch (Ghent), 33: 1283

    Dickes, G.J. and Nicholas, P.V.J. (1969) Assoc. Pub. Analysts, 7: 14

    Diechmann, W.B., Dressler, I., Keplinger, M. and MacDonald, W.E.
    (1968) Retention of dieldrin in blood, liver and fat of rats fed
    dieldrin for six months. Industr. Med. Surg., 37: 837-839

    Diechmann, W.B., MacDonald, W.E., Radomski, J., Blum, E.B.,
    Bevilacqua, M., and Keplinger, M. (1970) The tumorigenicity of aldrin,
    dieldrin and endrin in the albino rat. Industr. Med., 39: 314

    Donninger, C., Potter, D., Potter, S.A. and Wright, A.S. (1967) Liver
    cell changes induced by the oral administration of dieldrin and
    phenobarbitone to rats. Unpublished report from Tunstall Laboratory,
    Shell Research Ltd., Sittingbourne

    Donninger, C. (1969) Liver cell changes following the oral
    administration of dieldrin to mice. Unpublished report from the
    Tunstall Laboratory, Shell Research Ltd., Sittingbourne

    Duggan, R.E. and Lipscomb, G.Q. (1969) Dietary intake of pesticide
    chemicals in the United States (II), June 1966-April 1968. Pest.
    Monit. J., 2(4): 153-162

    Elgar, K.E. (1966) Analysis of crops and soils for residues of the
    soil insecticides aldrin and telodrin. J. Sci. Fd. Agr., 17: 541-545

    FAO/WHO (1967) Evaluations of some pesticide residues in food,
    FAO,PL:CP/15; WHO/Food Add./67.32 p. 3-4.

    FAO/WHO (1968) 1967 Evaluations of some pesticide residues in food.
    FAO/PL: 1967/M/11/1; WHO/Food Add./68.30

    Feil, V.J., Hedda, R.D., Zayliskie, R.G. and Zachrison, C.N. (1970)
    Dieldrin-14C metabolism in sheep. Identification of
    trans-6-7-dihydroxyaldrin and 9-(synepoxy)
    exodimethanonophthalene. J. Agr. Fd. Chem., 18: 120-24

    Findlay, E. and Hamilton, G.A. (1968) Pesticide residues in foodstuffs
    in Great Britain. VIII Organochlorine pesticide residues in eggs and
    poultry. J. Sci. Fd. Agric., 19: 609-611

    Gannon, N., Link, R.P. and Decker, G.C. (1959a) Pesticide residues in
    meat. Storage of dieldrin in tissues of steers, hogs, lambs and
    poultry fed dieldrin in their diets. J. Agr. Fd. Chem., 7: 826-828

    Gannon, N., Link, R.P. and Decker, G.C. (1959b) Pesticide residues in
    meat and milk. Storage of dieldrin in tissues and its excretion in
    milk of dairy cows fed dieldrin in their diets. J. Agr. Fd. Chem.,
    7: 824-826

    Gillett, J.W. and Chan, I.M. (1968) Cyclodiene insecticides as
    inducers, substrates and inhibitors of microsomal epoxidation. J. Agr.
    Food Chem., 16: 590-593

    Good, E.E. and Ware, G.W. (1969) Effects of insecticides on
    reproduction in the laboratory mouse. IV Endrin and dieldrin. Toxicol.
    appl. Pharmacol., 14: 201-203

    Graves, J.B., Bonner, F.L., McKnight W.F., Watts, E.B. and Epps, E.A.
    (1969) Residues in eggs, preening glands, liver and muscle from
    feeding dieldrin-contaminated rice bran to hens and its effect on egg
    production, egg hatch and chick survival. Bull. Env. Contam. Tox.,
    4: 375-383

    Harr, J.R., Claeys, R.R., Bone, J.F. and McCorcle, J.W. (1970)
    Dieldrin toxicosis: rat reproduction. Amer. J. vet. Res., 31:

    Harris, L.E. and Greenwood, D.A. (1963) Effect of residues of newer
    insecticides on health. Unpublished progress report to Shell Chemical
    Company, letter signed by Joseph Street, dated 8 March 1963

    Hedde, R.D., Davison, K.C. and Robbins, J.D. (1970) Dieldrin 14-C
    metabolism in sheep. Distribution and isolation of urinary
    metabolites. J. Agr. Fd. Chem., 18: 116-119

    Hunter, C.G., Robinson, J. and Roberts, M. Pharmacodynamics of
    dieldrin (HEOD). Ingestion by human subjects for 18 to 24 months and
    postexposure for eight months. Arch. environm. Hlth., 18: 12-21

    Jager, K.W. (1970) "Aldrin, dieldrin, endrin and telodrin". An
    epidemiological and toxicological study of long-term occupational
    exposure. Thesis, 234 p., Elsevier, Amsterdam

    Jansen, J.D. (1969) Letter to A.M. Coetzee dated 25 July 1969

    Keane, W.T. and Zavon, M.R. (1969) Validity of a critical blood level
    for prevention of dieldrin intoxication. Arch. environm. Hlth., 19:

    Kinoshita, P.K. and Kempf, C.K. (1970) Quantitative measurements of
    hepatic microsomal enzyme induction after dietary intake of
    chlorinated hydrocarbon insecticides. Tox. Appl. Pharmacol., 17: 288

    Klein, A.K., Link J.D. and Ives, N.F. (1968) Isolation and
    purification of metabolites found in the urine of male rats fed aldrin
    and dieldrin. J. Ass. Off. agr. Chem., 51: 895-898

    Korte, F. and Arent, H. (1965) Metabolism of insecticides. IX (1)
    Isolation and identification of dieldrin metabolites from urine of
    rabbits after oral administration of dieldrin - 14C. Life Sci., 4:

    Korte, F. (1970) Terminal residues of cyclodiene insecticides. Comptes
    Rendus, XXV Conference, IUPAC, Cortina d'Ampezzo, Italy, July 1969.
    Appendix II: p. 172-180

    Korte, F. and Porter, P.E (1970) Minutes of the Fifth Meeting of the
    IUPAC Terminal Pesticide Residues, September 1970, Erbach, West
    Germany. Appendixes 4 and 4a

    Lee, D.F. (1968) Pesticide residues in foodstuffs in Great Britain.
    IX. Aldrin, dieldrin and other organochlorine pesticides in potatoes
    and carrots. J. Sci. Fd. Agric., 19: 701-705

    Lehner, P.N. and Egbert, A. (1969) Dieldrin and eggshell thickness in
    ducks. Nature, 224: 1218-1219

    Lichtenstein, E.P., Schulz, K.R., Fuhremann, T.W. and Liang T.T.
    (1970) Degradation of aldrin and heptachlor in field soils during a
    ten-year period. Translocation into crops. J. Agr. Fd. Chem., 18:

    Liska, et al. (1967) Food Technol. 21: 435-438

    Lofroth, G. (1970) Exposure of the general population to dieldrin.
    Letter to editor and reply Robinson J. and Roberts M. Fd. Cosmet.
    Toxicol., 8: 341-342

    Lutz-Ostertag, Y. and Lutz, H. (1969) Embryologie expérimentale. Note
    préliminaire sur les effets "oestrogènes" de l'"Aldrine" sur le
    tractus urogénital de l'embryon d'Oiseau. C.R. Acad. Sci. (Paris) Ser.
    D., 269: 484-486

    Maier-Bode, H. (1967) The aldrin and dieldrin contents of German
    edible carrots. Bull. environ. Contam. Toxicol., 2(1): 10-11

    Matthews, H.B. and Matsumura, F. (1969) Metabolic fate of dieldrin in
    the rat. J. Agr. Fd. Chem., 17: 845-852

    McGill, A.E.J. and Robinson, J. (1968) Organochlorine insecticide
    residues in complete prepared meals: a twelve-month survey in
    southeast England. Fd. Cosmet. Toxicol., 6: 45-57

    Mestres, R., Barthes, F. and Priu, M. (1967) DDT, aldrin and dieldrin
    residue determinations in milk and butter. Bull. Environ. Contam.
    Toxicol., 2(1): 25-33

    Moubry, R.J. and Myrdal, G.E. (1970) private communication, Wisconsin
    Department of Agriculture

    Nakatsugawa, T., Ishida, M. and Dahm, P.A. (1965) Microsomal
    epoxidation of cyclodiene insecticides. Biochem. Pharmacol., 14:

    Onsager, J.A., Rusk, H.W. and Butler, L.I. (1970) Residues of aldrin,
    dieldrin, chlordane and DDT in soil and sugarbeets. J. Econ. Entomol.,
    63: 1143-1146

    Parsons, A.M. and Moore, D.J. (1966) Some reactions of dieldrin and
    the proton magnetic resonance spectra of the products. J. Chem. Soc.
    (C), 2026-2031

    Polishuk, Z.W., Wasserman, M., Wasserman, D., Groner, Y., Luzarovici,
    S. and Tomatis, L. (1970) Arch. environm. Hlth., 20: 215-217

    Porter, R.D. and Wiemeyer, S.N. (1969) Dieldrin and DDT: Effects on
    sparrow hawk eggshells and reproduction. Science, 165: 199-200

    Potter, D., Wooder, M.F., Wright, A.S., Greenland, R.D. and
    Zavon, M.R. (1970) The effects of ingestion of foreign compounds on
    the sub-cellular structure and function of mammalian liver cells.
    Paper given by A.S. Wright at Sittingbourne, 14 May 1970

    Renvall, S. and Akerblom, M. (1968) Rester au organiska
    klorpesticider, sörskilt aldrin och dieldrin, 2 nagra svenska
    kalvöxter ochpotatis. Var. Föda, 20: 65-72

    Reports of the Government Chemist, H.M.S.O., London (1965-1969)

    Richardson, A. (1966) Ultra-violet conversion product of HEOD: Its
    concentration in various samples received from the USA. Shell Research
    Tunstall Report No. IRR TL/35/66

    Richardson, A. (1968) Residues of dieldrin and its ultraviolet
    decomposition product in selected samples. Shell Research Tunstall
    Report No. TLGR 0014.63

    Richardson, A., Baldwin, M. and Robinson, J. (1968) Identification of
    metabolites of dieldrin (HEOD) in the faeces and urine of rats. J.
    Sci. Fd. Agr., 19: 524-529

    Robinson, et al. (1965-66) Shell Research Ltd., Tunstall, Report
    PRRTL/12/65 and TU/23/66

    Robinson, J., Richardson, A. and Bush, B. (1966b) A photoisomerization
    product of dieldrin. Bull. environm. Contam. Toxicol., 1: 127-133

    Robinson, J., Roberts, M., Baldwin, M. and Walker, A.I.T. (1969) The
    pharmacokinetics of HEOD (dieldrin) in the rat. Fd. Cosmet. Toxicol.,
    7: 317-332

    Robinson, J. (1970a) Metabolites of dieldrin in the excreta of Rhesus
    monkeys. Unpublished information submitted in a letter to H.G.S. van

    Robinson, J. (1970b) Metabolites of dieldrin in the excreta of man.
    Unpublished information submitted in a letter to H.G.S. van Raalte

    Roe, F.J.C. and Grant, G.A. (1970) Inhibition by germ-free status of
    development of liver and lung tumours in mice exposed neonatally to
    7,12-dimethyl-benz(a) anthracene: implications in relation to tests
    for carcinogenicity. Int. J. Cancer, 6: 133-144

    Rosen, J.D., Sutherland, D.J. and Lipton, G.R. (1966) The
    photochemical isomerization of dieldrin and endrin and effects on
    toxicity. Bull. environm. Contam. Toxicol., 1: 133-140

    Ruzica, J.H.A., Simmond, J.H. and Tatton, J. O'G. (1967) Pesticide
    residues in foodstuffs in Great Britain. IV. Organochlorine pesticide
    residues in welfare foods. J. Sci. Fd. Agric., 18: 579-582

    Rymer, T.E. and Hammence, J.H. (1967) J. Ass. Pub. Analysts 5: 24

    Sakshaug, J. (1968) Residues of organochlorine insecticide in
    Norwegian butter samples 1966 (in Norwegian). J. Nord. Vet.-Med.,
    20: 696-701

    Shell International Chemical Co. (1968) Residues in potatoes resulting
    from soil applications of aldrin, Monograph, November

    Shell International Chemical Co. (1968) Residues in vegetables
    resulting from soil applications of aldrin, Monograph, November

    Shell International Chemical Co. (1968) Residues in small grains
    resulting from applications of aldrin, Monograph, November

    Smith, Klosterman and Dogger. (1966) Ann. Proc. N. Dakota Acad. Sci.,
    20: 96

    Tannenbaum, A. and Silverstone, H. (1949a) The genesis and growth of
    tumours. IV. Effects of varying the proportion of protein (casein) in
    the diet. Cancer Res., 9: 162-173

    Tannenbaum, A. and Silverstone, H. (1949b) The influences of the
    degree of calorie restriction in the formation of skin tumours and
    hepatomas in mice. Cancer Res., 9: 724-727

    van Steyvoort, L. et al. (1968) Meded. Rijksfac. Landbouwwettensch XX,
    the International Symposium, Ghent, May

    Walker, K. et al. (1965) The fate of aldrin, dieldrin and endrin
    residues daring the processing of sugar beets. United States
    Department of Agriculture, ARS. Publication, ARS-33-107, p. 8

    Walker, A.I.T., Stevenson, D.E., Robinson, J., Thorpe, E. and Roberts,
    M. (1969a) The toxicology and pharmacodynamics of dieldrin (HEOD):
    two-year oral exposures in rats and dogs. Toxicol. appl. Pharmacol.,
    15: 345-373

    Walker, A.I.T., Neill, C.H., Stevenson, D.E. and Robinson, J. (1969b)
    The toxicity of dieldrin (HEOD) to Japanese quail (Coturnix coturnix
    japonica). Toxicol. appl. Pharmacol., 15: 69-73

    Walker, A.I.T., Thorpe, E. and Stevenson D.E. (1970a) The toxicology
    of dieldrin (HEOD): long-term oral toxicity experiments in mice.

    Unpublished report from the Tunstall Laboratory, TU/13/70, Shell
    Research Ltd., Sittingbourne. Proposed for publication in Fd. Cosmet.

    Walker, A.I.T., Thorpe, E. and Baldwin, M.K. (1970b) Toxicity studies
    on the ultra-violet conversion product of dieldrin (UVCPD): thirteen
    weeks oral experiment with rats. Shell Research Tunstall Report No.
    TLGR. 0053.69

    Walton, M.S., Beck, V. and Baron, R.L. (1970) Subacute toxicity of
    photodieldrin 3,4,5,6,6,7-hexachloro-12-oxahexacyclo-tridecane, a
    photodecomposition product of dieldrin. Tox. appl. Pharmacol., 17:

    Wasserman, M., Curnow, D.H., Forte, P.N. and Gurner Y. (1969) Storage
    of organochlorine pesticides in the body fat of people in Western
    Australia. Industr. Med. Surg., 37: 295-300

    Wasserman, M., Coetzee, A.M., Wasserman, D. and Lazarovici, S. (1969)
    Present state of the storage of the organochlorine insecticides in the
    general population of South Africa. Paper given at the IUPAC
    conference, Johannesburg

    Williams, S., Mills, P.A. and McDowell, R.E. (1964) Residues in milk
    of cows fed rations containing low concentrations of five chlorinated
    hydrocarbon pesticides. J. Ass. Off. Anal. Chem., 47: 1124-1128

    Winnett, G. and Reed, J.P. (1968) Aldrin, dieldrin, endrin and
    chlordane persistence -  a three-year study. Pest. Mon. J., 2(3):

    Winteringham, F.P.W. and Barnes, J.M. (1955) Comparative response of
    insects and mammals to certain halogenated hydrocarbons used as
    insecticides. Physiol. Rev., 35: 701-739

    Wright, A.S., Potter, D., Wooder, M.F., Donninger, C., Le Pelley,
    J.R., Potter, S.A., Ferrigan, L.W., Sykes, R., Dean, B., Pickering,
    R.G., Walker, A.I.T., Crabtree, A.N. and Richardson, A. (1968) Liver
    cell changes induced by the oral administration of dieldrin and
    phenobarbitone to female dogs. Unpublished report from the Tunstall
    Laboratory, Shell Research Ltd., Sittingbourne

    Wright, A.S., Greenland R.D., Zavon, M.R. and Donninger, C. (1969)
    Liver cell changes following the oral administration of dieldrin to
    Rhesus monkeys for 5.5-6 years. Unpublished report from the Tunstall
    Laboratories, Shell Research Ltd., Sittingbourne

    Zavon, M.R. (1970) The effect of long-continued ingestion of dieldrin
    on Rhesus monkeys. A six-year study. Unpublished report from the
    Kettering Laboratory, University of Cincinnati, submitted by Shell
    International Research.

    See Also:
       Toxicological Abbreviations
       Dieldrin (ICSC)
       Dieldrin (PIM 575)
       Dieldrin (FAO Meeting Report PL/1965/10/1)
       Dieldrin (FAO/PL:CP/15)
       Dieldrin (FAO/PL:1967/M/11/1)
       Dieldrin (FAO/PL:1968/M/9/1)
       Dieldrin (FAO/PL:1969/M/17/1)
       Dieldrin  (IARC Summary & Evaluation, Supplement7, 1987)
       Dieldrin (IARC Summary & Evaluation, Volume 5, 1974)