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    FLUSILAZOLE

    EXPLANATION

         Flusilazole is a fungicide.  It was reviewed for the first time
    at the present meeting.

    EVALUATION FOR ACCEPTABLE DAILY INTAKE

    BIOLOGICAL DATA

    Biochemical aspects

    Absorption, distribution and excretion

         14C-Flusilazole (uniformly phenyl labelled) was administered
    orally to two male and two female Charles River CD rats/group by one
    of three regimens: 1) a single dose of about 8 mg/kg bw with no
    preconditioning: 2) a single dose of about 8 mg/kg bw following
    preconditioning for 21 days on a diet containing 100 ppm
    flusilazole; or 3) a single dose of about 200 mg/kg bw with no
    preconditioning.  By 96 (regimen 1) and 168 hours (regimens 2 and
    3), 90% of the administered radioactivity was recovered in the urine
    and feces in both sexes.  Preconditioning did not affect excretion. 
    Excretion t1/2 was 31 hours in males and 37 hours in females. 
    There was a sex difference in the amount of material excreted in
    feces compared to urine.  In males total fecal recovery accounted
    for 87% of the dose with 8% in urine, but in females the
    corresponding figures were 59% and 23%.  No significant amount of
    radioactivity was expired as CO2 or volatile metabolites.  Tissue
    residues accounted for less than 25% of the dose with highest
    amounts in carcass, GI tract and liver (means less than 1%).

         An additional 1 male and 1 female rat were given a single dose
    of 14C-flusilazole (triazole-3-labelled) of about 8 mg/kg bw
    without preconditioning.  As with the phenyl-labelled material, 88%
    of the administered radioactivity was recovered in urine and feces
    within 96 hours.  However, the pattern of excretion was different
    with the predominant route being the urine.  In males, urinary
    radioactivity accounted for 78% of the dose, with 11% in feces; in
    females, the respective figures were 59% and 26%.  Total tissue
    residues were about 3% of the dose with the highest levels in
    carcass (approx. 2% of dose), skin, GI tract and liver (all less
    than .5% of dose (Anderson  et al. 1986).

         In another study, 14C-flusilazole (triazole-3-labelled) was
    given orally to groups of 5 male and 5 female Charles River
    Crl:CD(SD)BR rats by one of the following regimens: 1) a single dose
    of about 8 mg/kg bw without preconditioning; 2) a single dose of
    about 8 mg/kg bw following a 14-day treatment period with doses
    about 8 mg non-labelled material/kg bw/day by gavage; 3) a single
    dose of about 224 mg/kg bw without preconditioning.  Total recovery
    of radioactivity at 96 hours (regimen 1) or 120 hours (regimens 2
    and 3) was 92.6 to 99.2%.  Sex and regimen differences were not
    observed in this study.  Urinary excretion accounted for about 72%
    and fecal excretion for 17%.  About 90% of the material excreted was
    recovered in the first 48 hours with all regimens.  Tissue levels
    were low and excluding carcass were less than .2% of the dose.

    Carcass residues accounted for less than 3% of the dose (Cheng,
    1986).

    Biotransformation

         14C-Flusilazole was extensively metabolized when administered
    orally to Charles River CD rats.  Recovered parent compound
    accounted for 2-11% of the dose in all groups of animals and was
    round almost exclusively in feces;  urinary levels were less than 1%
    of the dose.  The chief fecal metabolites identified following
    dosing with phenyl labelled flusilazole were:
    [Bis(4-fluorophenyl)methyl] silanol (Metabolite 1) (about 30% of
    dose in males, 19% in females); [Bis(fluorophenyl)methylsily]
    methanol (Metabolite 2a) (about 9% of dose in both sexes); fatty
    acid conjugates of the latter (19% of dose in males, 10% in
    females); and disiloxane (about 11% of dose in males, 7% in
    females).  The same metabolites except for the fatty acid conjugates
    were found in urine but in smaller amounts; none exceeded 1% of the
    dose in males.  In females, urine contained 7.5% of the dose as
    metabolite 1 and 2.2% of the dose as metabolite 2a, and 1.9% of the
    dose as siloxane.

         Following dosing with triazole labelled flusilazole, the chief
    metabolite identified was 1H,1,2,4-triazole (metabolite 3) which was
    found predominantly in urine (63.8% of dose in males, 51.6% in
    females) with smaller amounts in feces (4.0% of dose in males, 17.2%
    of dose in females).

         The proposed metabolic pathway is shown in Figure 1 (Anderson,
    1986).

         Metabolite 1: [Bis(4-fluorophenyl)methyl]silano
         Metabolite 2a [Bis(4-fluorophenyl)methyl silyl]methanol
         Metabolite 2  1-0-[Bis(4-fluorophenyl)methyl silyl]methyl]--D-
                       glucopyranuronic acid
         Metabolite 3  1H-1,2,4-Triazole
         Metabolite 4  N-((4-fluorophenyl)methyl) glycine.

    FIGURE 1

    Toxicological studies

    Acute toxicity

         The acute toxicity of flusilazole to several animal species is
    given in Table 1.  Signs of toxicity following oral administration
    included weight loss, weakness, lethargy and, at higher doses,
    laboured breathing, convulsions and prostration.  Inhalation effects
    were chiefly laboured breathing and lung sounds.  Dermal
    administration resulted only in some local erythema.

        TABLE 1.  RESULTS OF ACUTE TOXICITY ASSAYS WITH FLUSILAZOLE

                                                                        

    SPECIES    SEX     ROUTE    LD50a/   ALDa/   REFERENCES
                                LC50b    ALCb
                                                                        

    Technical flusilazole

    Rat        M       oral              1500    Wylie et al. 1983

    Rabbit     M&F     oral               350    Redgate et al. 1985

    Mouse      M       oral               680    Wylie et al. 1985
               F       oral              1000    Wylie et al. 1985

    Rat        M       oral       1110           Wylie et al. 1984a
               F       oral        674           Wylie et al. 1984a

    Rabbit     M&F     dermal    >2000           Gargus et al. 1983

    Rat        M       inhal.          2.7b,c    Poindexter et al. 1984
               F       inhal.          3.7b,c    Poindexter et al. 1984

    Rat        M&F     inhal.    >5.0b           Turner et al. 1985

    Formulation - 40% flusilazole

    Rat        M       oral       1865           Wylie et al. 1984b
               F       oral       1272           Wylie et al. 1984b
                                                                        

    a  mg/kg bw
    b  mg/l
    c  test material was 99% pure.
    
    Short-term studies

    Oral studies

    Rat

         Groups of six male Crl:CD rats were given 0 or 300 mg
    flusilazole (95.5%) in corn oil/kg bw/day by oral gavage for 2 weeks
    (5 days per week). After the tenth dose 3 rats/group were killed and
    examined for histopathology.  The remaining rats were killed after a
    14-day recovery period.  One treated rat died after the fifth dose
    (found Day 7).  The treated rats died lost weight during the first
    week of treatment and showed alopecia, diarrhea, stained face and
    perineal area, salivation and hypersensitivity during the treatment
    period only.  Liver vacuolation was seen in all treated animals.  In
    urinary bladder transitional epithelium hyperplasia and vacuolation
    were seen in all sacrificed treated animals with an increase in
    mitotic figures seen in two of three males killed immediately
    following the treatment period.  Two treated males had atypical
    giant cells in the lumen of the seminiferous tubules and necrosis
    and cellular degeneration of the germinal epithelium in the testes. 
    Hyperplasia and vacuolation of the transitional epithelium in the
    kidney pelvis was seen in two treated males.  Lesions tended to be
    more severe in animals killed immediately after the treatment period
    than in those from the recovery  phase (Wylie  et al. 1984c).

         A 90-day feeding study was carried out in Charles River (CD)
    rats with dietary levels of flusilazole (96.7%) of 0, 25, 125 and
    375 ppm fed to groups of 16 rats/sex and 750 ppm fed to 10 rats/sex. 
    Groups of 10/sex/dose comprised the standard 90-day study while the
    extra 6/sex/dose continued on diet for a one generation one litter
    reproduction study and then received control diet for a 4-month
    recovery phase.  Body weight gains were reduced only in the females
    given 750 ppm.  There were no effects on food consumption, clinical
    signs of toxicity, hematological parameters or urinalyses.  Serum
    cholesterol levels were increased in both males and females given
    750 ppm.  Absolute and relative liver weights were increased in both
    sexes at 750 ppm.  Mild urothelial hyperplasia was observed in
    urinary bladders of 5 males and 8 females at 750 ppm and 1 male and
    4 females at 375 ppm.  After the 4-month recovery phase following
    dosing with 0-375 ppm flusilazole, no evidence of bladder
    hyperplasia was observed.  At 750 ppm 5 males had liver lesions,
    chiefly hepatocyte hypertrophy in 5 males and fatty
    change/hepatocytolysis in 4 males.  The NOAEL was 125 ppm (equal to
    10 mg/kg bw/day) (Pastoor  et al. 1983).

    Mouse

         Groups of 20 male and 20 female Crl:CD-1 mice were given diets
    containing 0, 25, 75, 225, 500 or 1000 ppm of flusilazole (96.7%
    pure).  After four weeks on these diets 10 mice/sex/group were
    sacrificed.  The remaining 10 mice/sex/group were sacrificed after
    90 days of treatment.  There were no effects noted on body weight,
    food consumption or clinical signs of toxicity in animals sacrificed
    at either interval.  At 90 days high-dose males and females had
    slightly reduced Hb, Hct and RBC counts which were statistically
    significant for at least one of these parameters in each sex.  No
    other hematological changes were noted.  At both 4 weeks and 90 days
    absolute and relative liver weights were increased in male mice at
    225 ppm and higher and in female mice at 75 ppm and higher.  The
    absolute and relative kidney weights in males at 1000 ppm were
    decreased.  At 90 days hepatocellular hypertrophy was observed in
    4/10 females at 1000 ppm and 8-10/10 males at 225, 500, and
    1000 ppm.  Hepatocellular vacuolar cytoplasmic changes were observed
    in both sexes (incidences 0, 0, 0, 2, 7, 10 in males and 0, 0, 1, 3,
    9, and 8 in females, at 0, 25, 75, 225, 500, and 1000 ppm,
    respectively).  Urothelial cell hyperplasia in urinary bladder was
    observed in 1/10 males and 7/10 males at 500 and 1000 ppm,
    respectively, and 2/10, 3/10, and 6/10 females at 225, 500 and
    1000 ppm, respectively.  No treatment-related kidney lesions were
    observed.  Tissues from animals killed at 4 weeks were not examined. 
    The NOAEL in this study was 25 ppm (equal to 4.5 mg/kg bw/day)
    (Pastoor  et al. 1984).

    Dog

         Four beagle dogs/sex/group were given diet containing 0, 25,
    125, or 750/500 ppm flusilazole (93% pure) for 3 months.  At the
    highest dose level the dogs were given diet containing 750 ppm
    flusilazole for 3 weeks, control diet for one week and then a dose
    level of 500 ppm for the remainder of the study.  The dose level was
    reduced because of body weight loss and reduced food intake at
    750 ppm.  At 500 ppm the males gained a mean of 0.2 kg while the
    females lost a mean of 0.5 kg body weight.  The other two groups
    were comparable to controls (gains of 1.6-1.9 kg in both sexes). 
    Food consumption remained lower than controls at the 750/500 ppm
    dose level.  Clinical signs related to treatment were observed in
    one male and two females at 500 ppm (weakness or tremors).  One
    female at 25 ppm was sacrificed  in extremis week 5.  No other
    animal died.  In males at 750/500 ppm WBC count and monocyte counts
    were slightly but statistically significantly increased and
    cholesterol levels, total protein and albumen levels were lower than
    controls.  In both sexes at 750/500 ppm and males at 125 ppm alanine
    amino transerase levels were higher than controls.  Absolute and
    relative liver weights were increased in both sexes at 750/500 ppm
    and were considered related to treatment.  Other organ weight
    differences were probably related to the decreased body weights at

    750/500 ppm.  Mild mucosal hyperplasia in the urinary bladder was
    observed in all males  and females at 500 ppm and in 2 males at
    125 ppm.  In the stomach, hyperlasia of lymphoid follicles in the
    pyloric granular mucosa was observed in 0/4, 3/4, 4/3, and 4/4 males
    and 0/4, 0/4, 3/4, and 4/4 females at 0, 25, 125, and 750/500 ppm,
    respectively.  On the basis of this effect in stomach a NOAEL was
    not demonstrated in this study (Richard  et al. 1983).

         Groups of 5 beagle dogs/sex were given diets containing 0, 5,
    20, or 75 ppm flusilazole (95.8% pure) for one year.  Although all
    treated groups of females had lower weight gains than controls, this
    did not appear to be treatment-related.  No body weight effects were
    seen in males.  No treatment-related effects were noted in food
    consumption or clinical signs of toxicity.  WBC counts were higher
    in both sexes at 75 ppm than in the controls.  Alkaline phosphates
    levels were higher than controls and cholesterol levels lower in
    both sexes at 75 ppm but the difference was statistically
    significant only in males.  The 75 ppm males also had lower total
    protein and albumen levels in serum.  Relative liver weights were
    increased in both sexes at 75 ppm and relative kidney weight in
    females at 75 ppm.  There was centrilobular hepatocyte enlargement
    at 20 and 75 ppm, in both sexes with distinct vacuolation in 3
    high-dose males.  There were also a higher degree of centrilobular
    inflammation in all of the high-dose dogs both with regard to
    relative numbers of inflammatory cells and to increased number of
    hepatic veins involved.  All dogs in all groups including controls
    had lymphoid hyperplasia in the gastric mucosa but the degree
    increased with dose level and was moderate only in high-dose males
    and females.  There were no treatment-related kidney or urinary
    bladder effects.  The NOAEL in this study was 5 ppm (equal to
    0.14 mg/kg bw/day) (O'Neal  et al. 1985).

    Dermal studies

    Rabbit

         A study in New Zealand White rabbits in which groups of 5-10
    rabbits/sex were treated dermally with 0, 25, 250 or 2000 mg
    flusilazole/kg bw/day (95.8% pure material) was terminated after 6
    days exposure because of serve erythema with necrosis in animals at
    250 and 2000 mg/kg bw/day.  The erythema was first observed Day 4 of
    test.

         A range-finding study with 175 or 250 mg flusilazole (94.9%) kg
    bw/day produced only mild erythema at both levels.

         A 21-day study was performed in groups of 5 New Zealand White
    rabbits/sex/dose at dose levels of 0, 1, 5, 25, and 200 mg
    flusilazole (94.9% pure)/kg bw/day.  For application the test
    material was moistened with distilled water.  The exposure sites
    were occluded for 6 hours and then washed free of remaining test

    material.  There were no apparent treatment-related effects on body
    weights: hematology; clinical chemistry; or liver, kidney and spleen
    weights.  At 200 mg/kg bw/day, four males and 2 females had
    persistent mild erythema beginning Days 6 to 12.  At termination
    slight to mild diffuse hyperplasia/thickening of epidermis was
    observed in the skin of one male and two females at 25 mg/kg bw/day
    and three males and two females at 200 mg/kg bw/day (Sarver  et al.
    1986).

    Long-term/carcinogenicity studies

    Rats

         Groups of 70 male and 70 female Crl:CD(SD)BR rats were given
    diets containing 0, 10, 50 or 250 ppm flusilazole (95.6% pure) for
    two years.  Additionally, groups of 10/sex were given the same dose
    levels for 6 months and 1 year. After about 100 days on test, 20
    rats/sex/group were mated for the reproduction phase of the study. 
    These rats were returned to the long-term study after weaning of the
    second litter.  Body weights, food consumption and clinical
    condition were monitored throughout the study.  Hematology and
    clinical chemistry parameters were examined at 3, 6, 9, 12 and 24
    months on fasted animals.  The animals sacrificed at 6 months were
    examined for bladder lesions only.  About 40 tissues/organs were
    examined for control and high-dose animals and liver, bladder,
    kidney, lung and gross lesions for the low and intermediate dose
    groups sacrificed after one year.  For animals that died on test or
    were sacrificed at two years all tissues from all animals in all
    groups were examined.

         Survival to two years was 39-57% in the various groups with no
    treatment-relationship.  Survival did not drop below 50% in any
    group until Week 98.  The high-dose males had slightly lower body
    weights from 6 months to the end of the study but there was no
    similar effect in females.  There were no treatment-related effects
    on food consumption, clinical signs of toxicity, hematology,
    clinical chemistry or urinalysis.  In females, relative liver
    weights were increased at both one and two years at 250 ppm and at
    one year only at 50 ppm.  No effect was observed in males.  No
    treatment-related effects on the urinary bladder were observed at 6
    months.  After one year there was an increased incidence of
    hepatocellular hypertrophy in females (0/10, 0/10, 1/10, and 7/10 at
    0, 10, 50, and 250 ppm, respectively) and at 250 ppm polyploidy
    (increased number of multinuclear hepatocytes) was observed in two
    females with none in any other group. There were no liver changes in
    males at one year.  There was an increased incidence of
    hydronephrosis in males (0/10, 0/10, 3/10, and 4/10 at 0, 10, 50 and
    250 ppm).  Urothelial hyperplasia in renal pelvis was observed in
    one male at 50 pm and one at 250 ppm, but not in any other group. 
    Treatment-related lesions were not observed in urinary bladders of
    males.  Females did not show kidney or bladder lesions after one

    year.  Among rats dying on test or sacrificed after two years there
    were increased incidences in livers of females of acidophilic foci
    of cellular alterations (3, 3, 4, and 13 at 0, 10, 50, and 250 ppm,
    respectively) and diffuse fatty change (9, 9, 12, and 23,
    respectively, in 63-68 /group).  There were no treatment-related
    liver lesions in males.  In females, there was an increased
    incidence of pyelonephritis in kidney (3, 3, 8, and 10,
    respectively), but no treatment-related lesions were observed in
    males. The only tumours which were increased in incidence in treated
    groups were squamous cell carcinomas of the oral and nasal cavities
    in males (0/66, 1/63, 0/67, and 3/64, respectively).  Historical
    control data from six two-year feeding studies showed five studies
    which no squamous cell carcinomas of oral or nasal origin while the
    remaining study had an incidence of 2/60.  These data suggest that
    these tumours may occur randomly as clusters and that the incidence
    in this study was not treatment-related.  There was, therefore, no
    evidence of oncogenicity.  It is noted, however, that the effects
    noted were relatively mild and higher doses might have been
    tolerated.  The NOAEL for non-neoplastic effects was 10 ppm (equal
    to 0.45 mg/kg bw/day) (Pastoor  et al. 1986).

    Mouse

         Groups of 80 Crl:CD-1(ICR)BR mice/sex were given a diet
    containing 0, 5, 25, or 200 ppm flusilazole (93%-95.6% purity) for
    18 months.  Additional groups of 10/sex/dose were given the same
    diets for 6 months.  Survival to 18 months was 76-86% in males and
    57-80% in females with the highest survival at the high-dose level. 
    There were no treatment-related effects on body weight, food
    consumption, hematology or serum protein.  There was a higher
    incidence of skin sores in high-dose males and females but these
    were mainly ear lesions which were noted at the beginning of the
    study and appeared to be related to the animal identification
    process.  High-dose males also had an increased incidence of ruffled
    fur.  Absolute and relative liver weights were increased in males at
    200 ppm at both 6 and 18 months and in 200 ppm females at 6 months. 
    Absolute kidney weight only was decreased in females at 200 ppm at
    18 months but the biological significance of this observation was
    not clear.  There were no treatment-related lesions in the kidney. 
    In the liver there was an increased incidence of hepatocellular
    fatty change in both males and females at 200 ppm at 18 months
    (40/80 and 24/80, respectively, compared to 4/80 and 2/79 in male
    and female controls.  One 200 ppm male at 6 months also had this
    lesion, although 8/80 males at the 25 ppm levels also had
    hepatoceullar fatty changes.  This incidence was not statistically
    significantly different from controls.  There was no treatment-
    related increase in incidence of any tumour type in this study.  The
    NOAEL in this study was 25 ppm (equal to 3.4 mg/kg bw/day) (Brock
     et al. 1985).

    Reproduction study

    Rat

         Groups of 6 Crl:CD(SD)BR rats/sex/dose level from the 90 day
    feeding study were mated within the same dose level for a period of
    15 days.  Dose levels were 0, 25, 125, and 375 ppm flusilazole
    (96.7% pure).  The females were examined daily for evidence of a
    copulation plug.  After the mating period, the females were housed
    individually.

         The number of pregnant females/group was 3-6.  The total number
    of pups born did not show a treatment-related effect but two of the
    five litters at 375 ppm were all dead at birth.  The remaining three
    litters at this dose level were 93-100% viable similar to the
    litters in the other groups including controls.  Mean pup weights at
    Day 4 were lower in the 375 ppm group than the other three groups. 
    At 375 ppm (equal to 29 mg/kg bw/day) pup weights remained slightly
    lower than the other groups to weaning (Pastoor  et al. 1983).

         Because of the small group size, the usefulness of this study
    is limited.

         Groups of 20 Crl:CD(SD)BR rats/sex/dose level from the chronic
    toxicity/oncogenicity study were mated within the same dose level
    for a period of 15 days after a dosing period of about 100 days. 
    Dose levels were 0, 10, 50, and 150 ppm flusilazole (95.6% pure). 
    The females were examined daily throughout the mating period for
    evidence of a copulatory plug.  At the end of the mating period the
    females were housed individually and allowed to give birth and raise
    their litters to weaning.  About one week after weaning of the F1a
    litters the females were sacrificed without pathological
    examination.  At weaning of the F1b litters 20 weanlings/sex/group
    were selected as parents for the F2 generation.  These weanlings
    were maintained on the same diets as their parents for a 90 day
    period before mating.  Mating procedures were the same for the F0 -
    F1 litters. It is stated that sibling matings were avoided.  For
    each litter the number of pups born, the number of pups born alive,
    the number alive at 24 hours, 4 days, 12 days and 21 days, the
    litter weight at 24 hours, and 4 days and the weight of male and
    female pups at 21 days were recorded.  At Day 4 all litters with
    more than 10 pups were culled to 10, with equal numbers of males and
    females where possible.  Pups found dead were discarded.  At weaning
    of the F2b pups 10/sex/group were randomly selected and necropsied. 
    Liver, kidney, testes and brain were weighed and about 26
    tissues/organs were examined for histopathology.

         Food consumption and body weights were recorded only for the
    pre-mating periods for the F0 and F1b animals.  There were no
    consistent differences during this period in F0 animals but F1b
    males given 250 ppm had lower body weights.  No differences in food

    consumption were noted.  Pregnancy rates were variable in all mating
    periods but with no dose-relationship.  There was no evidence of a
    treatment-related effect on male reproductive parameters.  There was
    some indication that gestation length might be longer in the
    high-dose group but this could not be determined unequivocally
    because of the number of animals for which gestation lengths could
    not be determined.  The number of pups dead at birth was increased
    in the 250 ppm group in all litters and in the 50 ppm group in the
    F2a litter.  Survival to Day 4 was reduced at 250 ppm in the F1a,
    F1b, and F2a litters. Loss of the entire litter perinatally was
    observed in 2, 2, 2 and 1 dams at 250 ppm in the F1a, F1b, F2a and
    F2b litters, respectively, and in 1 dam at 50 ppm in the F2a
    litter.  Survival after 4 days was similar in all groups.  The sex
    of pups is indicated only at weaning after culling of the litters so
    the sex ratio cannot be determined.  Pup weights were similar in all
    groups except for reduced weights at weaning in male and female pups
    in the F1b and F2a litters.  In the F2b weanling pups the absolute
    and relative liver weights in males in the 250 ppm group were
    increased.  No effect was observed in females.  The only
    pathological lesion of note was hydronephrosis in female weanlings. 
    The incidence of unilateral and bilateral lesions combined was 1/10,
    4/10, 3/10, and 5/10 at 0, 10, 50, and 250 ppm, respectively.  The
    incidences in the 10 and 250 ppm groups are slightly higher than
    those observed in 10 historical control groups over the period
    1982-1986.  However, neither the severity nor the incidence of the
    lesions showed a dose-related pattern so it is unlikely that this is
    treatment-related effect.  The NOAEL in this study was 10 ppm (equal
    to 0.85 mg/kg bw/day on the basis of pre-mating intake data)
    (Pastoor  et al. 1986).

    Special studies on mutagenicity

         Flusilazole was negative in seven mutagenicity studies (Table
    2).

    Special studies on teratology

    Rat

         In a pilot study in which groups of seven pregnant rats were
    given doses of 0, 100 or 300 mg flusilazole (99% pure)/kg bw/day
    Days 7-16 of gestation, 300 mg/kg bw was overtly toxic and 100 mg/kg
    bw slightly toxic to the dams.  Both levels were embryotoxic and
    300 mg/kg bw resulted in cleft palates in about 51% of the fetuses
    in each litter.


        TABLE 2.  RESULTS OF MUTAGENICITY ASSAYS ON FLUSILAZOLE

                                                                                                                          

                                                          CONCENTRATION
    TEST SYSTEM              TEST ORGANISM                OF FLUSILAZOLE          RESULTS       REFERENCE
                                                          (PURITY)
                                                                                                                          

    Ames testa               Salmonella typhimurium       1-250 ug/plate          Negative      Donovan & Irr, 1982
                             TA1535, TA1537, TA98,        (90%)
                             TA100

    Ames testa               Salmonella typhimurium       5-250 ug/plate          Negative      Arce et al. 1988
                             TA1535, TA97, TA98,          (97.7%)
                             TA100 

    Unscheduled DNA          Rat hepatocytes Crl (SD)     1 x 10-5 -              Negative      Chromey et al. 1983
    synthesis                                             1.1 x 102 mM
                                                          (95.5%)

    CHO/HGPRT assay          Chinese hamster ovary        0.04 - 0.15 mM          Negative      McCooey et al. 1983
    for gene mutationa       cells (CHO-K1/BH4 clone)     0.05 - 0.275 mM
                                                          with and without
                                                          activation, 
                                                          respectively
                                                          (95.5%)

    Micronucleus test        Mouse (CD-1)                 375 mg/kg bw in         Negative      Sorg et al. 1984
    (bone marrow)                                         corn oil
                                                          (91.5%)

    Chromosome aberration    Human lymphocytes            1.7 - 100 ug/ml         Negative      Vlachos et al. 1986
    assaya                                                (94.85%)
                                                                                                                          

    TABLE 2 (CONTD).

                                                                                                                          

                                                          CONCENTRATION
    TEST SYSTEM              TEST ORGANISM                OF FLUSILAZOLE          RESULTS       REFERENCE
                                                          (PURITY)
                                                                                                                          

    Chromosome assay         Rat (Crl:CD (SD))            50 - 500 mg/kg bw in    Negative      Farrow et al. 1983
    (bone marrow)                                         corn oil (not given)
                                                                                                                          

    a  with and without metabolic activation.
    

         Groups of 25 female Crl:CD(SD)BR rats mated to males of the
    same strain were given doses of 0, 10, 50, or 250 mg flusilazole
    (95.6%)/kg bw/day in corn oil by gavage Days 7-16 of gestation.  The
    day a copulation plug was observed was designated Day 1 of
    gestation.  Body weight, food consumption and clinical condition
    were monitored throughout the study.  On Day 21 of gestation, the
    rats were killed and examined for gross pathology, liver and uterine
    weights, and numbers of corpora lutea, implantations, live and dead
    fetuses.  The uterus of any apparently non-pregnant females was
    stained with ammonium sulfide to detect for early resorptions.  The
    fetuses were weighed and examined for external, visceral and
    skeletal abnormalities.

         Chromodacryorrhea, chromorhinorrhea, wet underbodies, or wet or
    yellow or brown stained perineal areas were observed at the
    250 mg/kg bw dose level with all but two females showing at least
    one of these signs.  The severity increased with continued dosing
    and decreased following cessation of dosing.  Some females at this
    dose level had red vaginal discharges or stains and there was a
    slightly increased incidence of focal alopecia.  Two of the dams
    died (Days 11 and 18).  At 50 mg/kg bw one dam had red vaginal
    discharge and one ruffled abdominal fur. Food consumption was
    reduced during dosing at 50 and 250 mg/kg bw.  At sacrifice relative
    liver weights were increased in the dams at 50 and 250 mg/kg bw.  At
    250 mg/kg bw mean fetal body weight was reduced, incidence of
    resorptions was increased and the number of live fetuses per litter
    was reduced.  Stunted fetuses were observed only in treated groups
    at incidences of 1, 4, and 3 fetuses at 10, 50, and 250 mg/kg bw. 
    Cleft palate and absence of renal papilla were observed in fetuses
    (12% and 9%, respectively) from dams given 250 mg/kg bw but not at
    lower doses.  At 50 mg/kg bw/day two fetuses (from 2 litters) had no
    innominate artery and one (from the same litter as one of the
    fetuses with no innominate artery) had a great vessel malformation
    in the heart.  These lesions were not seen in any other group so
    were probably incidental.  In all groups including controls there
    was a high incidence of hydrocephalus and/or dilated lateral
    ventricles of the brain.  The incidence was not dose-related and no
    hydrocephalus was observed in subsequent studies so this finding was
    not considered to be treatment-related.  The incidence of misaligned
    sternebra, extra ossification centres in ribs and ossification delay
    in sternebra were increased at all dose levels compared to controls. 
    There were increased incidences of rudimentary ribs at 50 and
    250 mg/kg bw and extra ribs at 250 mg/kg bw.  A NOEL was not
    demonstrated in this study since skeletal variations were increased
    at 10 mg/kg bw, the lowest dose tested.  Maternal toxicity was seen
    at 50 mg/kg bw. Teratogenic effects were observed at 250 mg/kg bw
    (Lamontia  et al. 1984a).

         A second study included groups of 24 mated female Crl:CD(SD)BR
    rats given doses of 0, 0.4, 2.0, 10.0, 50.0 or 250.0 (10 females) mg
    flusilazole (95.6%)/kg bw/day in corn oil by gavage Days 7-16 of
    gestation.  The day a copulation plug was observed was designated
    Day 1 of gestation.  Body weight, food consumption and clinical
    condition were monitored throughout the study.  On Day 21 of
    gestation the rats were killed and examined as in the study above.

         At 50 and 250 mg/kg bw/day the dams had reduced body weight
    gains during the early part of the dosing period but the difference
    was statistically significant only at 250 mg/kg bw.  Both groups had
    reduced food intakes during dosing.  Clinical signs of toxicity were
    observed at 250 mg/kg bw: alopoecia, brown stains of face and limbs
    and yellow staining of perineum.  Relative liver weights were
    increased in the 50 and 250 mg/kg bw groups.  The incidence of early
    resorptions was similar in all groups;  however, the number of dams
    with median or late resorptions was higher in groups given 10 mg/kg
    bw or more.  The mean number of live fetuses/litter was similar in
    all groups.  The incidence of stunted fetuses was increased at dose
    levels of 10 mg/kg bw and higher.  Cleft palate was observed in
    fetuses from dams given 250 mg/kg bw but not at lower doses. 
    Absence of renal papilla was observed only in treated groups but
    there was no dose-relationship and the observation was not
    considered to be treatment-related.  Hydrocephalus was not observed
    in any group.  Visceral (large renal pelvis and small renal papilla)
    and skeletal (ribs anomalies) variations were observed at 10 mg/kg
    bw and higher.  Absence of the innominate artery was observed in
    4(3) fetuses (litters) at 50 mg/kg bw and 1 fetus at 250 mg/kg bw. 
    Retarded development (delayed ossification of sternebra and
    vertebral arch) was also evident at dose levels of 10 mg/kg bw and
    higher.  The incidence of red foci in bladder of fetuses was
    increased at dose levels of 10 mg/kg bw and higher;  however, these
    lesions were non-specific and were considered to be of no biological
    significance.  The NOAEL in this study was 2 mg/kg bw/day (Lamontia
     et al. 1984b).

         In a dietary study, groups of 24 mated Crl:CD(SD)BR female rats
    were given diets containing 0, 50, 100, and 300 or 900 ppm
    flusilazole (94.8%) Days 7-16 of gestation.  The day a copulation
    plug was observed was designated Day 1 of gestation.  Body weights,
    food consumption and clinical condition were monitored throughout
    the study.  On Gestation Day 21 the rats were sacrificed and
    examined for gross pathology, liver and uterine weights and uterine
    contents.  Fetuses were weighed, sexed and examined for external
    visceral and skeletal abnormalities.

         One female at 300 ppm died on Day 19 of gestation.  The death
    was not considered to be related to treatment.  During Days 7-11 of
    gestation at the beginning of dosing weight gains in all treated
    groups were lower than in controls in a dose-related manner. 
    Significant reductions were noted Days 7-9 at 300 and 900 ppm.  Food

    consumption during dosing was lower than controls in all treated
    groups but reached significant reductions only at 300 and 900 ppm. 
    There were no treatment-related clinical signs of toxicity. 
    Relative liver weights did not indicate a significant treatment-
    related effect.  Pregnancy rate was high in all groups.  One dam at
    900 ppm totally resorbed its litter.  The incidence of early
    resorptions was similar in all groups.  However, there was an
    increased incidence (dose-related) of median and late resorptions at
    100 ppm and higher.  Litter size was inversely dose-related and
    significantly smaller than in controls in the 900 ppm group.  Small
    litters (less than 10 fetuses) were only seen at dose levels of
    100 ppm and above. The 50 ppm group was similar to controls.  The
    incidence of stunted fetuses was increased at 300 and 900 ppm.  Mean
    fetal weights were not affected.  No treatment-related malformations
    were observed. No fetuses showed cleft palate and incidence of
    absence of renal papilla was not dose or treatment-related.  Two
    fetuses from different litters in the 900 ppm group had slightly
    domed heads but hydrocephalus was not confirmed on visceral
    examination.  There was a significant dose-related increase in
    skeletal variations at dose levels of 100 ppm and higher with extra
    ossification of the sternebra at all 3 dose levels, and rudimentary
    ribs, extra ossification in cervical ribs and delayed ossification
    in the vertebral arches (cervical) at 300 and 900 ppm.  Red foci
    were observed in the bladder of a few fetuses at all dose levels
    with a slightly higher but not dose-related incidence at 100 ppm and
    above.  As in the previous study, these were not considered to be
    biologically significant.  The NOAEL in this study was 50 ppm (equal
    to 4.6 mg/kg bw) (Alvarez  et al. 1984).

         A study of prenatal and postnatal toxicity in rats was
    conducted in two phases.  For the prenatal study (phase 1), groups
    of 24 female Crl:CD(SD)BR rats were mated on a 1:1 basis with males
    of the same strain.  The day a copulation plug was observed was
    designated Day 1 of gestation.  On Days 7 through 16 the females
    were given a dose of 0, 0.2, 0.4, 2, 10, or 100 mg flusilazole
    (94.8% pure in 0.5% aqueous methyl cellulose)/kg bw by oral
    intubation.  Body weights, food consumption and clinical condition
    were monitored throughout the study.  On Day 21 of gestation the
    females of one group at each dose level were killed for examination
    of the uterine contents.  The extra control and 100 mg/kg bw groups
    were killed Day 22 of gestation in order to determine whether
    absence of renal papillae was a compound-related effect or an
    anomaly.

         Analyses of the dosing solutions indicates that the solution
    prepared for the first day of dosing contained only 6-19% of the
    nominal concentrations.  Since solutions were prepared daily this
    may have been given to only the one female/group that had reached
    Gestation Day 7 on that day and only two of these (one at 2 and one
    at 100 mg/kg) were pregnant.  However, the next analyses given were
    done on solutions prepared six days later and it is unknown whether

    the technical error causing the low concentrations was corrected
    before this date.  Subsequent analyses indicated concentrations
    75-110% of nominal.  Assuming the worst case, 13-16 pregnant
    females/group were given 1-6 doses which were about 10% of the
    intended dose level (mean duration of low doses was 3.4-3.7 days). 
    In each group there were 7-8 pregnant females which did not receive
    the low doses.

         Body weight gains and food consumption were lower than controls
    during dosing in the females given 100 mg/kg bw.  Stained chin was
    observed in many of the 100 mg/kg bw females and some showed
    perinasal staining and/or wet perineum. Absolute and relative liver
    weights were increased in dams at 100 mg/kg bw.  Pregnancy rate was
    83-96% in treated animals and 96-100% in controls; there was no dose
    relationship.  The number of early resorptions and dams with early
    resorptions did not differ among the groups.  However, there was an
    increased incidence of median and late resorptions at 100 mg/kg bw. 
    The numbers of stunted fetuses and dams with stunted fetuses were
    increased at 10 and 100 mg/kg bw (statistically significant only at
    100 mg/kg bw).  One fetus in each of the 100 mg/kg bw groups had no
    renal papilla unilaterally.  One other high-dose fetus had
    malformations: no tail and imperforate anus (group killed Gestation
    Day 22).  There was an increased incidence of bladder foci in the
    two 100 mg/kg bw groups compared to their respective controls. 
    However, the Gestation Day 22 control incidence was higher than the
    100 mg/kg bw group killed on Gestation Day 21.  Groups given 0.4,
    2.0 and 10.0 mg/kg bw had slightly higher incidences of bladder
    foci.  Incidence of small papilla in the kidney was increased at 10
    and 100 mg/kg bw but in the groups killed Gestation Day 21 the
    increase was not dose-related.  Incidence of distended ureter was
    increased at 10 and 100 mg/kg bw when expressed as % affected per
    litter.  The number of litters affected was slightly higher than
    controls in the Day 21 group at 100 mg/kg bw but not in the Day 22
    group.

         In the postnatal study (phase II), groups of 22 females
    Crl:CD(SD)BR rats were mated and dosed as in phase I except that
    only one control and one 100 mg/kg bw group were included.  The
    females were permitted to have their litters and raise them to
    weaning.  Body weights, food consumption and clinical signs were
    monitored throughout the gestation and lactation periods.  Offspring
    were counted and weighted by sex Days 0, 4 (before and after
    culling), 7 and 14 post partum.  Pups were weighed individually Day
    21.  At weaning the pups were sacrificed and subjected to gross
    necropsy.

         The dosing solutions were adequately prepared in this phase of
    the study.  At 100 mg/kg bw five dams died; four on Gestation Day 24
    or 25 (with apparently normal litters) and one four days post partum
    after delivering a litter (all dead) Day 25.  At 2.0 mg/kg bw one
    dam died Day 24 during delivery.  At 100 mg/kg body weight gain and

    food consumption were reduced during the first few days of dosing
    but were similar to controls for the remainder of the study.  A few
    dams at 100 mg/kg bw are stated to have shown pallor (4), hunching
    (2), weakness (2) and dystocia (1) during the puturition and
    lactation periods.  There was an increase in mean gestational length
    at 10 and 100 mg/kg bw.  In controls, gestation did not exceed 22
    days.  In treated groups a gestation period of 23 days was seen in
    2, 1, 4, 12, and 4 dams at 0.2, 0.4, 2.0, 10.0, and 100 mg/kg bw,
    respectively, and at 100 mg/kg bw 11 dams did not deliver until 24
    days gestation.  At 100 mg/kg the mean gestation length was 23.7
    days compared to 21.8 days in controls.  Among the 11 high-dose dams
    with parturition at Gestation Day 24, six had no live fetuses and
    the other five had 1-5 live pups (mean 3) and 1-7 dead pups (mean
    4.8).  At 10 mg/kg bw the longest gestation period was 23 days and
    there was no apparent effect on pup survival at birth.  At this dose
    four dams had one dead pup (of 6-15 pups in litter) at birth; two
    delivered Day 22 and two delivered Day 23.   This latter incidence
    of dead pups at birth was similar to that in controls.  Survival to
    Day 4 was decreased at 100 mg/kg bw but was similar to controls at
    the other dose levels. At 100 mg/kg bw 18% of the pups alive Day 0
    of lactation had died by Day 4 compared to 0.4-1.7% of the pups in
    the control and lower dose groups.  There was no effect on survival
    for the rest of the gestation period.  Litter size was reduced at
    100 mg/kg bw even when both live and dead pups in the litters were
    considered.  Mean litter size was slightly lower than controls in
    the 10 mg/kg bw group reaching statistical significance after
    culling.  This was the result of an increased number of litters with
    less than 10 pups (4 cf 0 in controls and 1-2 in the other treated
    groups).  Pup weights at birth were somewhat higher in the three
    highest dose groups than in controls.  At 2 and 10 mg/kg bw a few
    litters with higher weights were among those with a 23 day gestation
    length.  At 100 mg/kg bw mean, live litter weights were not as high
    as at 10 mg/kg bw mean, live litter weights were not as high as at
    10 mg/kg bw but other effects confound any comparisons.  No
    treatment-related effects on sex were apparent.  The only
    alterations noted in the weanlings were dilatation of the renal
    pelvis and distended ureter.  The incidence was not unequivocally
    dose-related although somewhat higher at 10 mg/kg bw/day.  It is
    stated that among the dead pups, absence of renal papilla was
    observed in only 2/42 pups and small papilla (size 1 or 2) was seen
    in only 4 pups (2 of each size).  Most of the dead pups were in the
    high-dose group so it is presumed that these observations were from
    that group.  In phase II the NOAEL was 2 mg/kg bw with the only
    effects being a slightly longer gestation period with a higher mean
    weight in a few animals (Alvarez  et al. 1985a).

    Rabbit

         Groups of 18 New Zealand White female rabbits were inseminated
    with semen from one of the two male rabbits of the same strain from
    the same source.  Day of insemination was designated Gestation Day
    0.  On Days 7-19 the females were given nominal doses of 0, 2, 5, or
    12 mg flusilazole (94.8%)/kg bw/day by gavage in corn oil (actual
    1.9, 4.8 and 10.1 mg/kg bw/day).  There were two deaths during
    treatment: one control female Day 19 and one high-dose female Day
    16.  Another control female died Day 23.  Periodic anorexia was
    observed in some rabbits in all groups and was not related to
    treatment.  No treatment-related effects were noted on clinical
    observations, body weight, mean food consumption, abortions (2 in
    controls, 3 in each of the treated groups), number of resorptions,
    number of live or dead (none in any group) fetuses, fetal weights,
    maternal liver weights or maternal pathology.  The total number of
    malformed fetuses was not increased by treatment.  The incidence of
    hydrocephalus was 1(1), 2(1), 4(2), and 4(3) fetuses (litters) in
    the nominal 0, 2, 5, or 12 mg/kg bw/day level groups, respectively. 
    There was no increase in any other malformation nor of any
    variation.  In three subsequent studies hydrocephalus was observed
    only in one fetus at 35 mg/kg bw/day and in none at any lower dose
    or in controls.  The incidence of hydrocephalus in this study,
    therefore, was not confirmed and could not be regarded as related to
    treatment.  The NOAEL in this study was the nominal 12 mg/kg bw/day
    level (actual 10.1 mg/kg bw/day) (Solomon  et al. 1984).

         A second study with 20 New Zealand White female rabbits/group
    artificially inseminated with sperm from one of three male rabbits
    tested dose levels of 0, 12, and 35 mg flusilazole (95%)/kg bw/day
    administered Days 7-19 of gestation by gavage.  In this study
    pregnancy rates were low particularly in the two treated groups (not
    dose-related). At 35 mg/kg bw/day, 2 of the does aborted and 10
    totally resorbed their litters with only one doe with a live litter
    at examination Day 29.  There was an increased incidence of vaginal
    discharge, discharge in cage and stained tail at this dose level as
    well as an increased incidence of periodic anorexia.  Since there
    was only one litter, no teratologic effects could be determined. 
    One fetus did have hydrocephalus.  Reproductive parameters at
    12 mg/kg bw/day did not differ from controls and there was no
    evidence of maternal toxicity at this level.  The NOAEL in this
    study was the nominal level of 12 mg/kg bw/day (actual 11 mg/kg
    bw/day) (Zellers  et al. 1985).

         A pilot dietary study in New Zealand White rabbits included 7
    females/group offered diets containing 0, 500, 1000, or 2000 ppm
    flulilazole (94.8%) on Days 7-19 of gestation.  Full results are not
    given but pregnancy rate was low at 500 and 1000 ppm /3/7 at each
    level and incidence of total resorption was high (4/7) at 2000 ppm.

         Dietary levels of 0, 300, 600, and 1200 ppm flusilazole (94.8%)
    were given to groups of 20 New Zealand White female rabbits days
    7-19 of gestation following artificial insemination (day of
    insemination designated Day 0 of gestation). Body weights, food
    consumption and clinical signs of toxicity were monitored throughout
    the study.  The rabbits were sacrificed Day 29 of gestation and
    examined for gross pathology, corpora lutea, numbers of live and
    dead fetuses or resorption sites.  The fetuses were examined for
    external, visceral and skeletal abnormalities.

         Body weights and food consumption were reduced during dosing. 
    There were no treatment-related clinical signs, pathological lesions
    or changes in liver weights.  Pregnancy rate was reduced in all
    treated groups with the lowest rate in the high-dose group.  The
    number of dams with total resorptions was increased in the 600 and
    1200 ppm groups.  There were no treatment-related effects on mean
    number of live fetuses, resorptions (in dams with fetuses) or fetal
    weights.  The number of litters available at 600 and 1200 ppm was
    small (3 at each dose level), so the validity of the incidence of
    fetal malformations and variations is uncertain at these levels. 
    There were no apparent effects at 300 ppm.

         Since the pregnancy rate was reduced in all treated groups
    another dietary study was performed with levels of 0, 30, 100, and
    300 ppm flusilazole in diet offered Days 7-19 of gestation to groups
    of 18 or 25 (300 ppm only) female New Zealand White rabbits
    artificially inseminated with sperm from proven male rabbits.  In
    this study pregnancy rate was low in all groups but particularly in
    the controls.  In the 0 and 300 ppm groups 25% and 29%,
    respectively, of the pregnant does totally resorbed their litters
    but there were no total resorptions in the other two groups. 
    Because of the low number of dams with litters available in the
    control group, the data in this study could not be adequately
    assessed and a NOAEL cannot be determined (Alvarez  et al. 1985b).

         It has been suggested by the company that the reproductive
    effects observed in these studies (reduced pregnancy and increased
    total resorptions) were the result of inadequate technique during
    artificial insemination.  This might explain the effects observed in
    the control group in the second dietary study.

    Special studies on skin irritation and sensitization

    Guinea Pig

         In young adult Hartley guinea pigs, a range-finding study
    indicated mild erythema, 24 hours after topical application to the
    skin of the test material (90% pure flusilazole).  The primary
    irritation study conducted with 5 and 50% solutions in demethyl
    phthalate did not demonstrate irritation in any of the 10 animals

    exposed.  Intradermal injections of 1% solutions of flusilazole (90%
    pure) in dimethyl phthalate weekly for 4 weeks in the same animals
    caused erythema and edema with necrotic centres at the injection
    sites at 24 hours.  Challenge with topical applications of 5 and 50%
    solutions did not demonstrate sensitization (Wylie  et al. 1984d).

         In another study using 97.7% pure flusilazole, young adult
    Duncan Hartley albino guinea pits (10/sex) were given 3 weekly
    dermal applications of the test material (slightly moistened with
    dimethyl phthalate) which was covered with plastic wrap for 6 hours. 
    No signs of irritation were observed in any of the animals after any
    of these induction applications.  Two weeks after the last induction
    treatment, the guinea pigs were challenged with a dermal application
    of test material on an untreated site which was then covered for 6
    hours.  No reaction was observed in any of the animals.  A positive
    control groups treated with 1-chloro,-2,4-dinitrobenzene (DNCB)
    showed several erythema with necrosis after the second and third
    induction applications and severe erythema after the challenge dose
    two weeks later (Brock  et al. 1988).

    Special study of eye irritation

    Rabbit

         Two male New Zealand White rabbits were given doses of 0.01 ml
    of undiluted flusilazole (90% pure) in the right conjunctival sac. 
    Both rabbits shoed mild conjunctival redness and chemosis at 1-4
    hours.  The washed eye also showed some discharge at one hour but no
    other effects.  The unwashed eye showed slight corneal opacity at
    1-4 hours and slight cloudiness on biomicroscope examination at
    24-48 hours.  The eye was normal at 72 hours.  The test material
    produced only transient mild irritation (Hall  et al. (1984).

    COMMENTS

         Flusilazole administered orally to rats was rapidly excreted in
    urine and feces.  The label (14C) from phenyl-labelled material was
    excreted predominantly in feces, with a sex difference in that males
    excreted higher amounts in feces than did females.  However,
    substantial variability existed.  When triazole-labelled material
    was given, the 14C was recovered predominantly in urine.  Although
    one study indicated a sex difference, with males excreting more in
    urine than females, a sex difference was not observed in a second
    study with more animals.  Tissue levels were low.  The highest
    levels were found in the carcass (about 2% of the dose after 96-120
    hours).  Flusilazole was extensively metabolized in the rat. 
    Recovered parent compound accounted to 2-11% of the dose and was
    recovered almost exclusively in feces.

         Flusilazole has a low acute toxicity in the species examined.

         In short-term (90-day) studies, urothelial hyperplasia in the
    urinary bladder was observed in rats, mice and dogs at dietary
    levels of 375, 225, and 125 ppm, respectively.  Liver lesions,
    including hepatocellular hypertrophy and hepatocellular vacuolar
    cytoplasmic changes, were also observed in the 90-day studies in
    rats and mice (at 750 and 225 ppm, respectively) and in a one-year
    study in dogs at 20 ppm.

         In a one-year feeding study in beagle dogs, centrilobular
    hepatocyte enlargement was observed at 20 and 75 ppm.  The NOAEL was
    5 ppm, equal to 0.14 mg/kg bw/day.

         In long-term feeding studies in rats and mice no bladder
    lesions were observed.  There was urothelial hyperplasia in the
    renal pelvis in 1 of 10 male rats at 50 ppm and 1 of 10 male rats at
    250 ppm for one year, but in none of the rats (7 of 10) given
    250 ppm at one year (hepatocellular hypertrophy) and two years
    (acidophilic foci of cellular alteration: 3/66, 6/63, 4/68, and
    13/65 at 0, 10, 50, and 250 ppm, respectively).  Male and female
    mice given 200 ppm for 18 months developed hepatocellular fatty
    changes (40/80 and 24/80, respectively, versus 4/80 and 2/70 in
    respective controls).  This effect was also reported in 8/80 male
    mice at 25 ppm, which was not statistically significantly different
    from controls.  There was no evidence of oncogenicity in either
    species.  The NOAEL in the rat study was 10 ppm (equal to 0.45 mg/kg
    bw/day).  The NOAEL in the mouse study was 5 ppm (equal to
    0.79 mg/kg bw/day).

         In a 2-generation, 2 litters per generation reproduction study
    in rats, flusilazole caused perinatal mortality in both F1 and F2
    litters of dams given dietary levels of 250 ppm.  There was some
    indication of increased gestation length at this dose level, an
    effect which was also observed in a post-natal toxicity study in

    rats at doses of 10 mg/kg bw/day (gavage) and higher.  Perinatal
    mortality was observed at 100 mg/kg bw/day in this study.  The
    biological significance of prolonged gestation in this study is
    uncertain.  The NOAEL was 10 ppm (equal to 0.895 mg/kg bw/day) but
    not at lower doses.  The NOAEL in rats was 2 mg/kg bw/day.  No
    teratogenic effects were seen in rabbits.  The NOAEL was 100 ppm
    (equal to 2.8 mg/kg bw/day) based on maternal toxicity.

         After reviewing all available  in vitro and  in vivo
    short-term tests, the Meeting concluded that there was no evidence
    of genotoxicity.

    TOXICOLOGICAL EVALUATION

    Level causing no toxicological effect

         Mouse:    25 ppm in the diet, equal to 3.4 mg/kg bw/day
         Rat:      10 ppm in the diet, equal to 0.45 mg/kg bw/day
         Dog:       5 ppm in the diet, equal to 0.14 mg/kg bw/day.

    Estimate of acceptable daily intake for humans

         0-0.001 mg/kg bw.

    Studies which will provide information valuable in the continued
    evaluation of the compound

         1.   Observations in humans.
         2.   Toxicity of the biotransformation products.

    REFERENCES

    Alvarez, L., Krauss, W.C. & Staples, R.E. (1984)  Developmental
    toxicity study in rats given INH-6573-66 in the diet on Days 7-16 of
    gestation.  Unpublished Report No. 432-84 from Haskell Laboratory,
    Newark, DE, USA.  Submitted to WHO by E.I. du Pont de Nemours and
    Co., Inc., Wilmington, DE, USA.

    Alvarez, L., Staples, R.E., & Kaplan, A.M. (1985a)  INH-6573. 
    Prenatal and postnatal toxicity study in rats dosed by gavage on
    Days 7-16 of gestation.  Unpublished Report No. 654-85 from Haskell
    Laboratory, Newark, DE, USA.  Submitted to WHO by E.I. du Pont de
    Nemours and Co., Inc., Wilmington, DE, USA.

    Alvarez, L., Staples, R.E., Driscoll, C.D. & Kaplan, A.M. (1985b) 
    INH-6573.  Developmental toxicity study in rabbits treated by diet
    on Days 7-19 of gestation.  Unpublished Report No. 337-85 from
    Haskell Laboratory, Newark, DE, USA.  Submitted to WHO by E.I. du
    Pont de Nemours and Co., Inc., Wilmington, DE, USA.

    Anderson, J.J., Stadalius, M.A. & Schlueter, D.D. (1986)  Metabolism
    of 14C-DPX-H6573 in rats.  Unpublished Report No. AMR-196-84 from
    E.I. du Pont de Nemours and Co., Inc., Wilmington, DE, USA. 
    Submitted to WHO by E.I. du Pont de Nemours and Co., Inc.,
    Wilmington, DE, USA.

    Arce, G.T., Matarese, C.C. & Sarrif, A.M. (1988)  Mutagenicity
    testing of INH-6573-21 in  Salmonella typhimurium plate
    incorporation assay.  Unpublished Report No. 59-88 from Haskell
    Laboratory, Newark, DE, USA. Submitted to WHO by E.I. du Pont de
    Nemours and Co., Inc., Wilmington, DE, USA.

    Brock, W.J., Rickard, R.W., Kaplan, A.M. & Gibson, J.R. (1985) 
    Long-term feeding study in mice with INH-6573.  Unpublished Report
    No. 278-85 from Haskell Laboratory, Newark, DE, USA.  Submitted to
    WHO by E.I. du Pont de Nemours and Co., Inc., DE, Wilmington, USA.

    Brock, W.J., Vick, D.A. & Chromey, N.C. (1988)  Closed-patch
    repeated insult dermal sensitization study (Buehler method) with
    INH-6573-21 in guinea pigs.  Unpublished Report No. 34-88 from
    Haskell Laboratory, Newark, DE, USA.  Submitted to WHO by E.I. du
    Pont de Nemours and Co., Inc., Wilmington, DE, USA.

    Cheng, T. (1986)  Rat metabolism study of [Triazole-3-14C]
    DPX-H6573.  Unpublished final report 6129-128 from Hazleton
    Laboratories America, Inc.  Submitted to WHO by E.I. du Pont de
    Nemours and Co., Inc., Wilmington, DE, USA.

    Chromey, N.C., Horst, A.L., McCooey, K.T. & Sarrif, A.M. (1983) 
    Unscheduled DNA synthesis/rat hepatocytes in vitro.  Unpublished
    Report No. 209-83 from Haskell Laboratory, Newark, DE, USA. 
    Submitted to WHO by E.I. du Pont de Nemours and Co., Inc.,
    Wilmington, DE, USA.

    Donovan, S.M. & Irr, J.D. (1982)  Mutagenicity evaluation in
     Salmonella typhimurium.  Unpublished Report No. 611-82 from
    Haskell Laboratory, Newark, DE, USA.  Submitted to WHO by E.I. du
    Pont de Nemours and Co., Inc., Wilmington, DE, USA.

    Farrow, M.G., Cortina, T. & Padilla-Nash, H. (1983)   In vivo bone
    marrow chromosome study in rats - H # 14,728 - Final Report. 
    Unpublished Report No.  201-636 (Haskell No. 288-83) by Hazleton
    Laboratories America, Inc.  Submitted to WHO by E.I. du Pont de
    Nemours and Co., Inc., Wilmington, DE, USA.

    Hall, J.A., Dashiell, O.L. & Kennedy, G.L. (1984)  Eye irritation
    test in rabbits.  Unpublished Report No. 582-82 from Haskell
    Laboratory, Newark, DE, USA.  Submitted to WHO by E.I. du Pont de
    Nemours and Co., Inc., Wilmington, DE, USA.

    Lamontia, C.L., Staples, R.E. & Alvarez, L. (1984a)  Embryo-fetal
    toxicity and teratogenicity study of INH-6573-39 by gavage in the
    rat.  Unpublished Report No. 444-83 from Haskell Laboratory, Newark,
    DE, USA.  Submitted to WHO by E.I. du Pont de Nemours and Co., Inc.,
    Wilmington, DE, USA.

    Lamontia, C.L., Staples, R.E. & Alvarez, L. (1984b)  Embryo-fetal
    toxicity and teratogenicity study of INH-6573-39 by gavage in the
    rat.  Unpublished Report No. 142-84 from Haskell Laboratory, Newark,
    DE, USA.  Submitted to WHO by E.I. du Pont de Nemours and Co., Inc.,
    Wilmington, DE, USA.

    McCooey, K.T., Chromey, N.C., Sarrif, A.M. & Hemingway, R.E. (1983) 
    CHO/HGPRT assay for gene mutation.  Unpublished Report No. 449-83
    from Haskell Laboratory, Newark, DE, USA.  Submitted to WHO by E.I.
    du Pont de Nemours and Co., Inc., Wilmington, DE, USA.

    O'Neal, F.O., Rickard, R.W., Kaplan, A.M. & Gibson, J.R. (1985) 
    One-year feeding study in dogs with INH-6573. Unpublished Report
    No. 461-85 from Haskell Laboratory, Newark, DE, USA.  Submitted to
    WHO by E.I. du Pont de Nemours and Co., Inc., Wilmington, DE, USA.

    Pastoor, T.P., Wood, C.K., Krahn, D.F. & Gibson, J.R. (1983) 
    Ninety-day feeding and one-generation reproduction study in rats
    with Silane [Bis(4-fluorophenyl)](methyl) (1H-1,2,4-triazol-1-
    ylmethyl) (INH-6573). Unpublished Report No. 483-83 from Haskell
    Laboratory, Newark, DE, USA.  Submitted to WHO by E.I. du Pont de
    Nemours and Co., Inc., Wilmington, DE, USA.

    Pastoor, T.P., Wood, C.K., Drahn, D.F. & Aftosmis, J.G. (1984) 
    Four-week range finding and ninety-day feeding study in mice with
    Silane [Bis(4-fluorophenyl)] (methyl) (1H-1,2,4-triazol-1-ylmethyl)
    (INH-6573).  Revised Unpublished Report No. 341-83 1-83 from Haskell
    Laboratory, Newark, DE, USA.  Submitted to WHO by E.I. du Pont de
    Nemours and Co., Inc., Wilmington, DE, USA.

    Pastoor, T.P., Rickard, R.W., Sykes, G.P., Kaplan, A.M. & Gibson,
    J.R. (1986)  Long-term feeding (combined chronic
    toxicity/oncogenicity study) and two-generation, four litter
    reproduction study in rats with INH-6573.  Unpublished Report
    No. 32-86 from Haskell Laboratory, Newark, DE, USA.  Submitted to
    WHO by E.I. du Pont de Nemours and Co., Inc., Wilmington, DE, USA.

    Poindexter, G.L., Henry, J.E., Kenney, L.A., Burgess, B.A. &
    Kennedy, G.L.  (1984)  Inhalation median lethal concentration
    (LC50) of INH-6573-41 by EPA Protocol.  Unpublished Report
    No. 553-83 by Haskell Laboratory, Newark, DE, USA. Submitted to WHO
    by E.I. du Pont de Nemours and Co., Inc., Wilmington, DE, USA.

    Redgate, D., Sarver, J.W. & Chromey, N.C. (1985)  Approximate lethal
    dose (ALD) of INH-6573-66 in rabbits.  Unpublished Report No. 54-85
    from Haskell Laboratory, Newark, DE, USA.  Submitted to WHO by E.I.
    du Pont de Nemours and Co., Inc., DE, Wilmington, USA.

    Richard, R.W., Wood, C.K., Krahn, D.F. & Aftosmis, J.G. (1983) 
    Three-month feeding study in dogs with Silane
    [Bis(4-fluorophenyl)](methyl) (1H-1,2,4-triazol-1-ylmethyl)
    (INH-6573).  Unpublished Report No. 461-83 from Haskell Laboratory,
    Newark, DE, USA.  Submitted to WHO by E.I. du Pont de Nemours and
    Co., Inc., Wilmington, DE, USA.

    Sarver, W., Vick, D.A., Valentine, R., Chromey, N.C. & Kaplan, A.M.
    (1986)  Twenty-one dose dermal toxicity study with INH-6573-82 in
    rabbits. Unpublished Report No. 744-86 from Haskell Laboratory,
    Newark, DE, USA.  Submitted to WHO by E.I. du Pont de Nemours and
    Co., Inc., Wilmington, DE, USA.

    Solomon, H.M., Alvarez, L., Staples, R.E. & Hamill, J.C. (1984) 
    Developmental toxicity study in rabbits given INH-6573 by gavage on
    Days 7-19 of gestation. Unpublished Report No. 333-84 from Haskell
    Laboratory, Newark, DE, USA. Submitted to WHO by E.I. du Pont de
    Nemours and Co., Inc., Wilmington, DE, USA.

    Sorg, R.M., Naismith, R.W. & Mathews, R.J. (1984)  Micronucleus test
    (MNT) OECD H # 15,314.  Unpublished Report No. PH 309A-DU-001-84
    from Pharmakon Research International (Haskell Report HLO-437-84). 
    Submitted to WHO by E.I. du Pont de Nemours and Co., Inc.,
    Wilmington, DE, USA.

    Turner, R.J., Kinney, L.A. & Chromey, N.C. (1985)  Inhalation median
    lethal concentration (LC50) of INH-6573 by EPA Guidelines. 
    Unpublished Report No.  1-85 by Haskell Laboratory, Newark, DE, USA. 
    Submitted to WHO by E.I. du Pont de Nemours and Co., Inc.,
    Wilmington, DE, USA.

    Vlachos, D.A., Covell, D.L. & Sarrif, A.M. (1986)  Evaluation of
    INH-6573-82 in the  in vitro assay for chromosome aberrations in
    human lymphocytes.  Unpublished Report No. 745-86 from Haskell
    Laboratory, Newark, DE, USA.  Submitted to WHO by E.I. du Pont de
    Nemours and Co., Inc., Wilmington, DE, USA.

    Wylie, C.N., Burgess, B.A. & Kennedy, G.L. (1983)  Acute oral test
    in rats.  Unpublished Report No. 78-83 from Haskell Laboratory,
    Newark, DE, USA.  Submitted to WHO by E.I. du Pont de Nemours and
    Co., Inc., Wilmington, DE, USA.

    Wylie, C.N., Henry, J.E., Ferenz, R.L., Burgess, B.A. & Kennedy,
    G.L. (1984a) Median lethal dose (LD50) in rats - EPA proposed
    guidelines, Newark, DE, USA. Unpublished Report No. 433-83 by
    Haskell Laboratory, Newark, DE, USA. Submitted to WHO by E.I.  du
    Pont de Nemours and Co., Inc., Wilmington, DE, USA.

    Wylie, C.N., Henry, J.E., Ferenz, R.L., Burgess, B.A. & Kennedy,
    G.L. (1984b) Median lethal dose (LD50) in rats - EPA proposed
    guidelines.  Unpublished Report No. 412-83 by Haskell Laboratory,
    Newark, DE, USA.  Submitted to WHO by E.I. du Pont de Nemours and
    Co., Inc., Wilmington, DE, USA.

    Wylie, C.N., Henry, J.E., Burgess, B.A. & Kennedy, G.L. (1984c)  
    Ten-dose oral subacute test in rats.  Unpublished Report No. 78-83
    from Haskell Laboratory,  Newark, DE, USA. Submitted to WHO by E.I.
    du Pont de Nemours and Co., Inc., Wilmington, DE, USA.

    Wylie, C.N., Henry, J.E., Dashiell, O.L. & Kennedy, G.L. (1984d) 
    Primary skin irritation and sensitization test on guinea pigs. 
    Unpublished Report No. 626-82 from Haskell Laboratory, Newark, DE,
    USA.  Submitted to WHO by E.I. du Pont de Nemours and Co., Inc.,
    Wilmington, DE, USA.

    Wylie, C.N., Redgate, D., Warheit, D.B. & Chromey, N.C. (1985) 
    Approximate lethal dose (ALD) of INH-6573-66 in male and female
    mice.  Unpublished Report No. 531-84 from Haskell Laboratory,
    Newark, DE, USA.  Submitted to WHO by E.I. du Pont de Nemours and
    Co., Inc., Wilmington, DE, USA.

    Zellers, J.E., Staples, R.E., Alvarez, L. & Kaplan, A.M. (1985) 
    Developmental toxicity study (supplemental) in rabbits dosed by
    gavage on Days 7-19 of gestation. Unpublished Report No. 699-85 from
    Haskell Laboratory, Newark, DE, USA.  Submitted to WHO by E.I. du
    Pont de Nemours and Co., Inc., Wilmington, DE, USA.


    See Also:
       Toxicological Abbreviations
       Flusilazole (Pesticide residues in food: 1995 evaluations Part II Toxicological & Environmental)