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    INTERNATIONAL PROGRAMME ON CHEMICAL SAFETY


    ENVIRONMENTAL HEALTH CRITERIA 42








    TECNAZENE






    This report contains the collective views of an international group of
    experts and does not necessarily represent the decisions or the stated
    policy of the United Nations Environment Programme, the International
    Labour Organisation, or the World Health Organization.

    Published under the joint sponsorship of
    the United Nations Environment Programme,
    the International Labour Organisation,
    and the World Health Organization

    World Health Orgnization
    Geneva, 1984


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CONTENTS


ENVIRONMENTAL HEALTH CRITERIA FOR TECNAZENE

1. SUMMARY AND RECOMMENDATIONS

    1.1. Summary
         1.1.1. Identity, analytical methods and
                 sources of exposure
         1.1.2. Environmental concentrations and
                 exposures
         1.1.3. Kinetics and metabolism
         1.1.4. Studies on experimental animals
         1.1.5. Effects on man
         1.1.6. Effects on the environment
    1.2. Recommendations

2. IDENTITY, PROPERTIES AND ANALYTICAL METHODS

    2.1. Identity
    2.2. Properties and analytical methods
         2.2.1. Physical and chemical properties
         2.2.2. Analytical methods

3. USES, ENVIRONMENTAL LEVELS AND EXPOSURES, TRANSPORT AND DISTRIBUTION

    3.1. Uses
    3.2. Environmental levels and exposures
         3.2.1. Levels in food
         3.2.2. General population exposure
    3.3. Transport and distribution

4. KINETICS AND METABOLISM

5. STUDIES ON EXPERIMENTAL ANIMALS

    5.1. Short-term exposures
         5.1.1. Single exposure
         5.1.2. Repeated exposure
    5.2. Long-term exposure
    5.3. Reproduction studies
    5.4. Teratogenicity
    5.5. Carcinogenicity

6. EFFECTS ON MAN

7. EFFECTS ON THE ENVIRONMENT

8. PREVIOUS EVALUATIONS OF TECNAZENE BY INTERNATIONAL BODIES

9. EVALUATIONS OF HEALTH RISKS FOR MAN AND EFFECTS ON THE ENVIRONMENT

    9.1. Evaluation of health risk for man
    9.2. Evaluation of overall environmental effects
    9.3. Conclusions

REFERENCES


TASK GROUP MEETING ON ENVIRONMENTAL HEALTH CRITERIA FOR
ORGANOCHLORINE PESTICIDES OTHER THAN DDT (ENDOSULFAN,
QUINTOZENE, TECNAZENE, TETRADIFON)

 Members

Dr E. Astolfi, Faculty of Medicine of Buenos Aires, Buenos
   Aires, Argentina

Dr I. Desi, Department of Environmental Hygienic Toxicology,
   National Institute of Hygiene, Budapest, Hungary

Dr R. Drew, Department of Clinical Pharmacology, Flinders
   University of South Australia, Bedford Park, South
   Australia

Dr S.K. Kashyap, National Institute of Occupational Health,
   Ahmedabad, India

Dr A.N. Mohammed, University of Calabar, Calabar, Nigeria

Dr O.E. Paynter, Office of Pesticide Programs, US
   Environmental Protection Agency, Washington DC, USA

Dr W.O. Phoon, Department of Social Medicine and Public
   Health, Faculty of Medicine, University of Singapore,
   Outram Hill, Singapore  (Chairman)

Dr D. Wassermann, Department of Occupational Health, The
   Hebrew University, Hadassah Medical School, Jerusalem,
   Israel

 Representatives of Other Organizations

Dr H. Kaufmann, International Group of National Associations
   of Agrochemical Manufacturers (GIFAP)

Dr V.E.F. Solman, International Union for Conservation of
   Nature and Natural Resources (IUCN), Ottawa, Ontario,
   Canada

 Secretariat

Dr S. Dobson, Institute of Terrestrial Ecology, Monks Wood
   Experimental Station, Abbots Ripton, Huntingdon, United
   Kingdom (Temporary Adviser)

Dr M. Gilbert, International Register for Potentially Toxic
   Chemicals, United Nations Environment Programme, Geneva,
   Switzerland

Dr K.W. Jager, Division of Environmental Health, International
   Programme on Chemical Safety, World Health Organization,
   Geneva, Switzerland  (Secretary)

 Secretariat (contd.)

Dr D.C. Villeneuve, Health Protection Branch, Department of
   National Health and Welfare, Tunney's Pasture, Ottawa,
   Ontario, Canada (Temporary Adviser)  (Rapporteur)

Mr J.D. Wilbourn, Unit of Carcinogen Identification and
   Evaluation, International Agency for Research on Cancer,
   Lyons, France


NOTE TO READERS OF THE CRITERIA DOCUMENTS                       
                                                                
    While every effort has been made to present information in  
the criteria documents as accurately as possible without unduly 
delaying their publication, mistakes might have occurred and are
likely to occur in the future.  In the interest of all users of 
the environmental health criteria documents, readers are kindly 
requested to communicate any errors found to the Manager of the 
International Programme on Chemical Safety, World Health        
Organization, Geneva, Switzerland, in order that they may be    
included in corrigenda, which will appear in subsequent volumes.
                                                                
    In addition, experts in any particular field dealt with in  
the criteria documents are kindly requested to make available   
to the WHO Secretariat any important published information      
that may have inadvertently been omitted and which may change   
the evaluation of health risks from exposure to the             
environmental agent under examination, so that the information  
may be considered in the event of updating and re-evaluation    
of the conclusions contained in the criteria documents.         


                           * * *


     A detailed data profile and a legal file can be obtained from 
the International Register of Potentially Toxic Chemicals, Palais 
de Nations, 1211 Geneva 10, Switzerland (Telephone no. 988400-
985850). 

ENVIRONMENTAL HEALTH CRITERIA FOR TECNAZENE

    Following the recommendations of the United Nations
Conference on the Human Environment held in Stockholm in 1972,
and in response to a number of World Health Resolutions
(WHA23.60, WHA24.47, WHA25.58, WHA26.68), and the
recommendation of the Governing Council of the United Nations
Environment Programme, (UNEP/GC/10, 3 July 1973), a programme
on the integrated assessment of the health effects of
environmental pollution was initiated in 1973.  The programme,
known as the WHO Environmental Health Criteria Programme, has
been implemented with the support of the Environment Fund of
the United Nations Environment Programme.  In 1980, the
Environmental Health Criteria Programme was incorporated into
the International Programme on Chemical Safety (IPCS).  The
result of the Environmental Health Criteria Programme is a
series of criteria documents.

    A WHO Task Group on Environmental Health Criteria for
Organochlorine Pesticides other than DDT (Endosulfan,
Quintozene, Tecnazene, Tetradifon) was held at the Health
Protection Branch, Department of National Health and Welfare
Ottawa from 28 May - 1 June, 1984.  The meeting was opened by
Dr E. Somers, Director-General, Environmental Health
Directorate, and Dr K.W. Jager welcomed the participants on
behalf of the three co-sponsoring organizations of the IPCS
(UNEP/ILO/WHO).  The Task Group reviewed and revised the draft
criteria document and made an evaluation of the health risks
of exposure to tecnazene.

    The drafts of this document were prepared by Dr D.C.
Villeneuve of Canada and Dr S. Dobson of the United Kingdom.

    The efforts of all who helped in the preparation and
finalization of the document are gratefully acknowledged.


                          * * *


    Partial financial support for the publication of this
criteria document was kindly provided by the United States
Department of Health and Human Services, through a contract
from the National Institute of Environmental Health Sciences,
Research Triangle Park, North Carolina, USA - a WHO
Collaborating Centre for Environmental Health Effects.


1.  SUMMARY AND RECOMMENDATIONS

1.1.  Summary

1.1.1.  Identity, analytical methods and sources of exposure

    Technical tecnazene (2,3,5,6-tetrachloronitrobenzene), is an 
odourless, crystalline solid that is used in its formulated form as 
a fungicide and as a sprout inhibitor on stored potatoes.  Gas 
chromatography with electron capture detection is the preferred 
method for its determination.

    Exposure of the general population is expected to be mainly 
through residues in food.  The residues reported are below the 
FAO/WHO maximum residue levels. 

    No cases of accidental or occupational overexposure have been 
reported.

1.1.2.  Environmental concentrations and exposures

    Tecnazene is rapidly lost from treated soil, probably mainly 
through evaporation. 

1.1.3.  Kinetics and metabolism

    Tecnazene is rapidly absorbed and metabolized in the rat and the 
rabbit following oral administration.  High single oral doses (3000 
mg in rabbit) are predominantly passed unchanged in the faeces.  
Several metabolities are presumed in urine, the most important being 
the mercapturic acid conjugate. 

1.1.4.  Studies on experimental animals

    Tecnazene is only slightly toxic according to the scale of Hodge 
& Sterner (1956).  The oral LD50 of tecnazene in the rat is 7500 
mg/kg body weight.  WHO (1984) has classified tecnazene in the 
category of technical products unlikely to present an acute hazard 
in normal use. 

    In long-term studies, no-observed-adverse-effect levels were:

    rat:    750 mg/kg diet for 104 weeks, equivalent to 38 mg/kg 
            body weight per day;

    mouse:  1500 mg/kg diet, equivalent to 200 mg/kg body weight 
            per day; and

    dog:    15 mg/kg body weight per day (administered orally by 
            capsule for 2 years).

    At higher dosages (4000 mg/kg in diets with rats and 240 mg/kg 
body weight in dogs), growth inhibition occurs and in dogs, the 
plasma alkaline phosphatase levels increase. 

    In the tests conducted so far, tecnazene did not affect 
reproduction (rats), nor was it embryotoxic or teratogenic (rats 
and mice).  No information on mutagenicity and other related short-
term tests is available.  Data available from a mouse and a rat 
study do not indicate that tecnazene is a carcinogen. 

1.1.5.  Effects on man

    Dermal sensitivity has been reported in agricultural workers.

1.1.6.  Effects on the environment

    A lack of effect on bacteria of the nitrogen cycle has been 
reported, but no other relevant information has been found. 

1.2.  Recommendations

    1.  Monitoring studies on occupationally-exposed
        workers, especially workers in greenhouses, are
        required concerning both levels of exposure and
        potential health effects.

    2.  More data should be made available on tecnazene
        levels in greenhouse crops.

    3.  The dermal toxicity, skin sensitization, and eye
        irritation capacity of tecnazene should be determined
        in both experimental animals and in the occupational
        setting.

    4.  The genotoxicity and cell transformation capacity
        of tecnazene should be studied.  If these studies
        indicate a need for it, an adequate carcinogenicity 
        study should be done.

    5.  The level of hexachlorobenzene as an impurity in
        tecnazene should be kept as low as possible.

2.  IDENTITY, PROPERTIES AND ANALYTICAL METHODS

2.1.  Identity

Chemical Structure

Molecular formula:            C6HCl4NO2

CAS chemical name:            2,3,5,6-tetrachloronitrobenzene

Common trade names:           Chipman 3,142, Folosan, Fusarex,
                              Fumite, Folosan DB905, TCNB

CAS registry Number:          117-18-0

Relative molecular mass:      260.88

2.2.  Properties and Analytical Methods

2.2.1.  Physical and chemical properties

    Tecnazene is a colourless, odourless, crystalline solid with a 
melting point of 99 C.  It is fairly volatile at room temperature.  
It is readily soluble in carbon disulfide, benzene, chloroform, 
ketones, and aromatic and chlorinated hydrocarbon compounds.  It is 
practically insoluble in water (0.44 mg/litre at 20 C), and its 
solubility in ethanol is 40 g/litre at 25 C (Worthing, 1979).  
Tecnazene is generally very stable; it can be dispersed by 
pyrotechnic mixtures.  It decomposes slowly in solution when 
exposed to ultraviolet radiation.  The technical grade material is 
more than 99% pure and contains less than 1% of hexachlorobenzene. 

2.2.2.  Analytical methods

    Polarographic, colorimetric, and gas chromatography combined 
with a flame detector method are described in the literature, but 
gas chromatography with an electron-capture detector is the 
preferred method for the determination of tecnazene residues 
(Dalziel & Duncan, 1974; FAO/WHO, 1979).  The limit of detection 
with this method is approximately 0.01 mg/kg with a recovery of 
more than 90% (FAO/WHO, 1979). 

3.  USES, ENVIRONMENTAL LEVELS AND EXPOSURES, TRANSPORT AND
DISTRIBUTION

3.1.  Uses
  
    Tecnazene is used as a sprout inhibitor on stored potatoes and 
as a fungicide.  In the latter application it is mainly used as a 
smoke generator formulation in greenhouses (Table 1). 

Table 1.  Usage data for tecnazene in selected countriesa
-------------------------------------------------------------------
Area             Quantity    Year     Use
-------------------------------------------------------------------
Sweden           200 kg      1981     horticultural use against
                                      fungi in greenhouses

United Kingdom   0.14 tonne  1975-79  fungicide and sprout sup-
                 per year             pressant; used as a dust or
                                      spray on potatoes in storage

USA              unknown     1981     fungicide
-------------------------------------------------------------------
a From: IRPTC, personal communication, 1984.

3.2.  Environmental Levels and Exposures

    No data are available on levels in air and water, or on
occupational exposure levels.

3.2.1.  Levels in food

    Washing, peeling, and cooking potatoes reduced levels of 
tecnazene (Dalziel & Duncan, 1974).  Potatoes that had been treated 
with 3% tecnazene at a rate of 4.5 g/kg were found to contain 3 
mg/kg, after 4 - 5 months storage (FAO/WHO, 1979).  Washing reduced 
the levels of tecnazene to below 1 mg/kg, and peeling further 
reduced the levels to below 0.1 mg/kg.  Another 50% loss of 
tecnazene occured when the peeled potatoes were boiled.  Market 
basket surveys in the USA of about 300 potato samples revealed that 
14 samples had detectable residues of tecnazene (i.e., 0.001 mg/kg 
or more).  Trace levels (0.01 mg/kg or less) of tecnazene were 
found in 15 out of 3500 samples of USA foodstuffs (FAO/WHO, 1979).  
Analyses of vegetable products in Belgium and Sweden for tecnazene 
revealed that most of the lettuce, chicory, mushrooms, carrots, 
sweet peppers, corn, etc., had levels between 0.001 and 0.01 mg/kg 
fresh weight (Valange, 1974; FAO/WHO, 1979). 

    The WHO/FAO (1979) has recommended temporary maximum residue 
(tolerance) levels (MRL) for tecnazene (Table 2). 

Table 2.  Temporary maximum residue (tolerance) levels (MRL) for 
tecnazene
-----------------------------------------------------------------
Commodity                          Temporary MRL (mg/kg)
-----------------------------------------------------------------
Lettuce                            2
Potatoes (washed before analysis)  1
Chicory (witloot)                  0.2
Other vegetables                   0.1
Tomatoes                           0.1
-----------------------------------------------------------------

3.2.2.  General population exposure

    Environmental exposure is probably low due to its limited use 
outdoors. 

3.3.  Transport and Distribution

    Tecnazene is rapidly lost from sandy soil, probably mainly 
because of its volatility (FAO/WHO, 1979). 

4.  KINETICS AND METABOLISM

    Rabbits receiving a single oral dose of 0.1 - 3.0 g/animal 
eliminated 60 - 78% in the faeces within 3 days, while the urine 
accounted for 35 - 38% (primarily as conjugated products).  At 0.01 
g/animal, 22 - 30% was recovered in the faeces (Bray et al., 1953). 

    Mercapturic acid conjugate was excreted at a rate of 11% within 
48 h of the administration of 1 - 3 g of tecnazene to rabbits.  
Other metabolites excreted included an ether glucuronide (12%), 
2,3,5,6-tetrachloroaniline (10%), unconjugated 4-amine-2,3,5,6-
tetrachlorophenol (2%) and an etheral sulfate (1%) (Bray et al., 
1953; Betts et al., 1955).  A suggested pathway for the 
biotransformation of tecnazene in rabbits based on data obtained 
from Betts et al. (1955) is shown in Fig. 1.  Similar amounts of 
mercapturic acid were excreted in the urine of rats dosed with 
tecnazene (Barnes et al., 1959).  Tecnazene administered orally to 
pigeons was converted to mercapturic acid (Wit & Reenwangh, 1969). 

FIGURE 1

5.  STUDIES ON EXPERIMENTAL ANIMALS

5.1.  Short-Term Exposures

5.1.1.  Single exposure

    The acute oral LD50 for tecnazene in the rat is 7500 mg/kg
body weight (Klimmer, 1971). The acute intraperitoneal LD50 in
the rat is 3500 mg/kg body weight (Wit et al., 1960).

5.1.2.  Repeated exposure

    Tecnazene at 0, 1344, or 13 440 mg/kg diet was fed to groups of 
mice (12 mice per group) for 31 days.  No adverse effects were 
observed at the 1344 mg/kg level, but growth was inhibited at 13 
440 mg/kg (Buttle & Dyer, 1950). 

    Groups of rats (5 males, 5 females per group) received 
tecnazene at 0, 800, 4000, and 20 000 mg/kg diet for 10 weeks.  
Death occurred at 20 000 mg/kg; growth was reduced at 4000 mg/kg.  
There were no effects on growth or mortality rate at 800 mg/kg 
(Buttle & Dyer, 1950).  Tecnazene at 2000 mg/kg, fed to rats for 10 
weeks, did not have any effects on the general health, blood 
picture, autopsy findings, and histological pictures of the liver 
and kidney.  Increased liver and testes weights were observed in 
the males (no other details reported) (Wit et al., 1960). 

    Groups of pigs (2 per group) were fed tecnazene at 0, 120, 800, 
or 1200 mg/kg of potatoes for 26 weeks (1200 mg/kg, equivalent to 
7.1 g tecnazene/pig per day or 50 mg/kg body weight).  Reduced body 
weight gains were observed in the first half of the study for the 
animals in the highest-dose group.  General health, and results of 
haematological tests, and gross and microscopic examination of the 
liver and kidney were not affected (Abrams et al., 1950). 

5.2.  Long-Term Exposure

    In a 2-year study, groups of beagle dogs (2 males and 2 females 
per group; controls - 1 male and 1 female) were treated orally (by 
capsule) with 0, 3.75, 15, 60, or 240 mg tecnazene/kg body weight 
per day, for 6 days a week.  At the 240 mg level, all animals died 
within the first year of the study, and microscopic changes were 
observed in liver, kidney, and bone marrow.  Growth was normal in 
all animals at 60 mg/kg, and the clinical chemistry was normal at 
15 mg/kg (Donikian et al., unpublished data, 1965). 

5.3.  Reproduction Studies

    In a two-generation reproduction study, groups of rats (5 males 
and 5 females per group) were fed tecnazene at 0, 200, 800, or 3200 
mg/kg diet for 12 weeks, prior to mating.  No effects on reproduction 
were noted at any dose level.  Maternal growth was slightly inhibited 
at the 3200 mg/kg dose level during the 12 week feeding period in 
each generation, and fatty infiltration of the liver was noted.  No 
effects were observed in the animals on the 800 mg/kg diet (Buttle, 
unpublished data, 1974). 

5.4.  Teratogenicity

    CD rats and C57B116 mice were administered doses of up to 200 
mg tecnazene/kg body weight orally on gestation days 7 -18.  Neither 
embryotoxic nor teratogenic effects were observed (Courtney et al., 
1976).  In the same study, CD-1 mice administered the same doses 
orally on days 7 - 16, also did not show any effects. 

5.5.  Carcinogenicity

    Groups of 65 male and 65 female rats were fed a diet containing 
tecnazene (purity 99%) at doses of 0, 750, and 1500 mg/kg for 104 
weeks.  The feeding did not affect general appearance, behaviour, 
mortality rates, or food consumption.  In the second half of the 
treatment period, a slight reduction in body weight was observed in 
males in the 1500 mg/kg group.  The macropathological findings and 
non-neoplastic histological changes were those commonly found in 
the strain used; thus they were not considered to be treatment-
related and did not show clear dose relationships.  Thirty-nine 
females of the control group, 48 females of the 750 mg/kg group, 
and 50 females of the 1500 mg/kg group had benign or malignant 
tumours of the mammary glands.  Adenocarcinomas of the mammary 
gland were found in 4 females of the control group, 5 in the 750 
mg/kg group, and 8 in the 1500 mg/kg group.  These differences are 
of borderline statistical significance (Ben-Dyke et al., 
unpublished data, 1978a). 

    Tecnazene (purity 99%) was administered continuously in the 
diet to 65 male and 65 female mice in each dose group at levels of 
0, 750, and 1500 mg/kg for 80 weeks.  The only dose-related 
distribution of neoplasms observed was pulmonary adenoma in the 
male animals of the 1500 mg/kg group (8 animals showed this lesion, 
compared with 4 in the control group) (Ben-Dyke et al., unpublished 
data, 1978b). 

6.  EFFECTS ON MAN

    Occupational dermal sensitivity has been reported in 
agricultural workers (Lupuknova, 1965). 

7.  EFFECTS ON THE ENVIRONMENT

    Tecnazene has no effect on the bacteria involved in the nitrogen 
cycle.  At 100 mg/kg in a fine sandy loam, no effects were found on 
the respiration of microorganisms on nitrification (Caseley & 
Broadbent, 1968). 

    No other relevant information on the environmental toxicity of 
tecnazene was found. 

8.  PREVIOUS EVALUATIONS OF TECNAZENE BY INTERNATIONAL BODIES

    The Joint Meeting on Pesticide Residues (JMPR) reviewed 
residues and toxicity data on tecnazene in 1974, 1978, 1981, and 
1983 (FAO/WHO, 1975, 1979, 1982, 1984).  Although further 
toxicological information is still required on tecnazene, the 
meeting concluded that the no-observed-adverse-effect levels for 
the rat, mouse, and dog were 750 mg/kg in the diet, 1500 mg/kg in 
the diet, and 15 mg/kg body weight (by capsule), respectively, and 
estimated the acceptable daily intake (ADI) for man to be 0 - 0.01 
mg/kg body weight. 

    WHO, in its "Guidelines to the Use of the WHO Recommended 
Classification of Pesticides by Hazard" (WHO, 1984), classified 
tecnazene in the list of technical products unlikely to present an 
acute hazard in normal use. 

9.  EVALUATION OF HEALTH RISKS FOR MAN AND EFFECTS ON THE 
ENVIRONMENT

9.1.  Evaluation of Health Risks for Man

    Tecnazene toxicity

    Tecnazene is only slightly toxic according to the scale of
Hodge & Sterner (1956).  The oral LD50 in the rat was 7500 mg/kg 
body weight.  WHO (1978) classified tecnazene in the category of 
technical products unlikely to present an acute hazard in normal 
use. 

    Tecnazene is rapidly absorbed and metabolized in animals after 
oral administration, and with higher doses, an increasing amount is 
passed unchanged in the faeces. 

    In long-term studies the no-observed-adverse-effect levels are:

    rat:    750 mg/kg diet, equivalent to 38 mg/kg body
            weight per day;

    mouse:  1500 mg/kg diet, equivalent to 200 mg/kg body
            weight per day; and

    dog:    15 mg/kg body weight per day (administered
            orally by capsule).

    At higher dosage levels tested, growth inhibition occurs and in 
the dog there are increases in plasma alkaline phosphatase levels. 

    Tecnazene was neither embryotoxic nor teratogenic in the 
studies reported.  There is no information on mutagenicity or other 
related short-term tests.  Based on the results of an oral feeding 
study on the mouse and the rat, there are no indications of 
carcinogenicity. 

    The only observation in man has been dermal sensitivity.

    Exposure to tecnazene

    Exposure of the general population is expected to be mainly via 
residues in food.  The residue data available are below the FAO/WHO 
maximum residue limits. 

    No data are available on tecnazene levels in air and water and 
on the levels of occupational exposure. 

    No cases of human overexposure have been reported.

    Hazard assessment

    The experimental animal data available indicate that tecnazene 
(purity greater than 99%) has a low degree of toxicity, even in 
long-term studies.  An acceptable daily intake has been estimated 
at 0.01 mg/kg body weight. 

    In the absence of human exposure data, other than residues in 
food, a factual hazard assessment of present total exposure cannot 
be made. 

    The data available on tecnazene would indicate a low degree of 
concern in relation to human health effects. 

9.2.  Evaluation of Overall Environmental Effects

    In the absence of information on levels in the environment and 
effects on the environment, such an evaluation cannot be made. 

9.3.  Conclusions

    1.  The general population does not seem to be at
        risk from exposure to tecnazene.

    2.  With the exception of one report on dermal
        sensitization in agricultural workers, tecnazene does
        not seem to be a problem occupationally.

    3.  With the exception of information on the
        bacteria involved in the nitrogen cycle there are no
        available data on other environmental effects.  Since
        the use of this chemical is mainly confined to
        greenhouses there is little concern for risk to the
        general environment.

REFERENCES

ABRAMS, T.J., SCORGIE, N.J., & WILLIS, G.A.  (1950)  Pig
feeding trials with 2,3,5,6-tetrachloronitrobenzene.  Br. vet.
 J., 106: 413-420.

BARNES, M.M., JAMES, S.P., & WOOD, P.B.  (1959)  The formation
of mercapturic acids. I. Formation of mercapturic acid and the
levels of glutathione in tissues.  Biochem. J., 71: 680-690.

BETTS, J.J., JAMES, S.P., & THORPE, W.V.  (1955)  The
metabolism of pentachloronitrobenzene and 2,3,4,6-tetrachloro-
nitrobenzene and the formation of mercapturic acids in the
rabbit.  Biochem. J., 61: 611-617.

BRAY, H.G., HYBS, Z., JAMES, S.P., & THORPE, W.V.  (1953)  The
metabolism of 2,3,5,6- and 2,3,4,5-tetrachloronitrobenzenes in
the rabbit and the reduction of aromatic nitro compounds in
the intestine.  Biochem. J., 53: 266-273.

BUTTLE, G.A.H. & DYER, F.J.  (1950)  Experiments on the
toxicology of 2,3,5,6-tetrachloronitrobenzene.  J. Pharm.
 Pharmacol., 2:  371-375.

CASELEY, J.C. & BROADBENT, F.E.  (1968)  The effect of five
fungicides on soil respiration and some nitrogen
transformations in yolo fine sandy loam.  Bull. environ.
 Contam. Toxicol., 8: 58-64.

COURTNEY, K.D., COPELAND, M.F., & ROBBINS, A.  (1976) The
effects of pentachloronitrobenzene, hexachlorobenzene and
related compounds on fetal development.  Toxicol. appl.
 Pharmacol., 35: 239-256.

DALZIEL, J. & DUNCAN, H.J.  (1974)  Studies on potato sprout
suppressants. I. Residual levels of tecnazene in lab-treated
and in commercial samples of potatoes.  Potato Res., 17:
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    See Also:
       Toxicological Abbreviations
       Tecnazene (HSG 12, 1988)
       Tecnazene (WHO Pesticide Residues Series 4)
       Tecnazene (Pesticide residues in food: 1978 evaluations)
       Tecnazene (Pesticide residues in food: 1981 evaluations)
       Tecnazene (Pesticide residues in food: 1994 evaluations Part II Toxicology)