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    IPCS INTERNATIONAL PROGRAMME ON CHEMICAL SAFETY
    Health and Safety Guide No. 38

    CYHALOTHRIN AND LAMBDA-CYHALOTHRIN
    HEALTH AND SAFETY GUIDE






    UNITED NATIONS ENVIRONMENT PROGRAMME

    INTERNATIONAL LABOUR ORGANISATION

    WORLD HEALTH ORGANIZATION




    WORLD HEALTH ORGANIZATION, GENEVA 1990

    This is a companion volume to Environmental Health Criteria 99:
    Cyhalothrin

    Published by the World Health Organization for the International
    Programme on Chemical Safety (a collaborative programme of the United
    Nations Environment Programme, the International Labour Organisation,
    and the World Health Organization)

    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

    WHO Library Cataloguing in Publication Data

    Cyhalothrin and lambda-cyhalothrin : health and safety guide.

    (Health and safety guide ; no. 38)

    1. Pyrethrins  - standards  I. Series

    ISBN 92 4 151038 2          (NLM Classification: WA 240)
    ISSN 0259-7268

    (c) World Health Organization 1990

    Publications of the World Health Organization enjoy copyright
    protection in accordance with the provisions of Protocol 2 of the
    Universal Copyright Convention.  For rights of reproduction or
    translation of WHO publications, in part or  in toto, application
    should be made to the Office of Publications, World Health
    Organization, Geneva, Switzerland.  The World Health Organization
    welcomes such applications.

    The designations employed and the presentation of the material in this
    publication do not imply the expression of any opinion whatsoever on
    the part of the Secretariat of the World Health Organization
    concerning the legal status of any country, territory, city or area or
    of its authorities, or concerning the delimitation of its frontiers or
    boundaries.

    The mention of specific companies or of certain manufacturers'
    products does not imply that they are endorsed or recommended by the
    World Health Organization in preference to others of a similar nature
    that are not mentioned.  Errors and omissions excepted, the names of
    proprietary products are distinguished by initial capital letters.

    CONTENTS

    INTRODUCTION

    1. PRODUCT IDENTITY AND USES
         1.1. Identity
         1.2. Physical and chemical properties
         1.3. Analytical methods
         1.4. Uses

    2. SUMMARY AND EVALUATION
         2.1. Human exposure 
         2.2. Environmental exposure and fate
         2.3. Uptake, metabolism, and excretion
         2.4. Effects on organisms in the environment
         2.5. Effects on experimental animals and in vitro test systems
         2.6. Effects on human beings

    3. CONCLUSIONS AND RECOMMENDATIONS
         3.1. Conclusions
         3.2. Recommendations

    4. HUMAN HEALTH HAZARDS, PREVENTION AND PROTECTION, EMERGENCY ACTION
         4.1. Main human health hazards, prevention and protection, first
              aid
              4.1.1. Advice to physicians
              4.1.2. Health surveillance advice
         4.2. Explosion and fire hazards
         4.3. Storage
         4.4. Transport
         4.5. Spillage and disposal
              4.5.1. Spillage
              4.5.2. Disposal

    5. HAZARDS FOR THE ENVIRONMENT AND THEIR PREVENTION

    6. INTERNATIONAL CHEMICAL SAFETY CARD

    7. CURRENT REGULATIONS, GUIDELINES, AND STANDARDS
         7.1. Previous evaluations by international bodies
         7.2. Exposure limit values
         7.3. Specific restrictions
         7.4. Labelling, packaging, and transport
         7.5. Waste disposal

    BIBLIOGRAPHY
    

    INTRODUCTION

    The Environmental Health Criteria (EHC) documents produced by the
    International Programme on Chemical Safety include an assessment of
    the effects on the environment and on human health of exposure to a
    chemical or combination of chemicals, or physical or biological
    agents.  They also provide guidelines for setting exposure limits.

    The purpose of a Health and Safety Guide is to facilitate the
    application of these guidelines in national chemical safety
    programmes. The first three sections of a Health and Safety Guide
    highlight the relevant technical information in the corresponding EHC. 
    Section 4 includes advice on preventive and protective measures and
    emergency action; health workers should be thoroughly  familiar with
    the medical information to ensure that they can act efficiently in an
    emergency.  Within the Guide is an International Chemical Safety Card
    which should be readily available, and should be clearly explained, to
    all who could come into contact with the chemical.  The section on
    regulatory information has been extracted from the legal file of the
    International Register of Potentially Toxic Chemicals (IRPTC) and from
    other United Nations sources.

    The target readership includes occupational health services, those in
    ministries, governmental agencies, industry, and trade unions who are
    involved in the safe use of chemicals and the avoidance of
    environmental health hazards, and those wanting more information on
    this topic.  An attempt has been made to use only terms that will be
    familiar to the intended user.  However, sections 1 and 2 inevitably
    contain some technical terms.  A bibliography has been included for
    readers who require further background information.

    Revision of the information in this Guide will take place in due
    course, and the eventual aim is to use standardized terminology. 
    Comments on any difficulties encountered in using the Guide would be
    very helpful and should be addressed to:

    The Manager
    International Programme on Chemical Safety
    Division of Environmental Health
    World Health Organization
    1211 Geneva 27
    Switzerland

    THE INFORMATION IN THIS GUIDE SHOULD BE CONSIDERED AS A STARTING POINT
    TO A COMPREHENSIVE HEALTH AND SAFETY PROGRAMME

    1. PRODUCT IDENTITY AND USES

    1.1  Identity

    Cyhalothrin is a chlorotrifluoro derivative of chrysanthemic acid. 
    Although theoretically it could be a mixture of 16 enantiomers, this
    number has been reduced to 4 in actual practice.

    Lambda-cyhalothrin consists of the more active pair of enantiomers of
    cyhalothrin.

    Chemical structure:

    CHEMICAL STRUCTURE 1

    Molecular formula:            C23H19ClF3NO3

    Trade names:                  Cyhalothrin: "Grenade"
                                  Lambda-cyhalothrin: "Karate", "Matador",
                                  "Icon"

    Synonyms:                     Cyhalothrin: R114563, PP563
                                  Lambda-cyhalothrin: R119321, PP321

    CAS chemical name:             (R+S)-alpha-cyano-3-(phenoxyphenyl)
                                  methyl- (1S+1R)-cis-3-( z-2-
                                  chloro-3,3,3,-trifluoroprop-
                                  1-enyl)-2,2-dimethylcyclopropane-
                                  carboxylate

    Chemical name:                alpha-cyano-3-phenoxybenzyl-3-(2-chloro-
                                  3,3,3-trifluoroprop-1-enyl)-2,2-
                                  dimethyl-cyclopropane-carboxylate

    CAS registry number:          cyhalothrin: 68085-85-8
                                  lambda-cyhalothrin: 91465-08-6

    Technical grade cyhalothrin contains more than 90% of the active
    material.  It is formulated in 5%, 10%, and 20% emulsifiable
    concentrates.

    Technical grade lambda-cyhalothrin contains more than 90% active
    ingredient.  It is formulated as 2.5%, 5.0%, 8.3%, and 12%
    emulsifiable concentrates and as a 0.8% ultra-low-volume (ULV)
    formulation.

    1.2  Physical and Chemical Properties

    Some physical and chemical properties of cyhalothrin and
    lambda-cyhalothrin are listed on the International Chemical Safety
    Card (section 6).

    Technical cyhalothrin is a yellow-brown viscous liquid with a mild
    odour.  Technical lambda-cyhalothrin is a beige solid with a mild
    odour.

    Cyhalothrin is extremely stable to light and at temperatures below
    220°C. Dilute aqueous solutions are subject to photolysis, which
    occurs at a moderate rate.

    1.3  Analytical Methods

    The most widely adopted procedures for the determination of
    cyhalothrin residues in crops, animal tissues and products, soil, and
    other environmental samples are based on extraction of the residue
    with organic solvent and clean-up of the extract as necessary by
    solvent-solvent partition and adsorption column chromatography,
    followed by determination of the residue using gas chromatography (GC)
    with electron capture detection (GC/ECD).  The identity of residues
    can be confirmed by GC with mass selective detection (GC-MSD) or by
    thin-layer chromatography (TLC) followed by GC/ECD.

    1.4  Uses

    Cyhalothrin is a pyrethroid insecticide, highly active against a wide
    range of species of Lepidoptera, Hemiptera, Diptera, and Coleoptera. 
    It also has some miticidal activity.  Lambda-cyhalothrin has the same
    spectrum of insecticidal activity as cyhalothrin, but is more active. 
    The compound is a stomach and contact insecticide.  It shows
    adulticidal, ovicidal and, particularly, larvicidal activity.

    Apart from agricultural uses, cyhalothrin also has public and animal
    health applications in which it effectively controls a broad spectrum
    of insects including cockroaches, flies, mosquitos, and ticks.  It is
    active as a residual spray on inert surfaces.

    2.  SUMMARY AND EVALUATION

    2.1  Human Exposure

    Residues in food arising from the use of cyhalothrin and lambda-
    cyhalothrin on crops and in animal health are low, usually less than
    0.2mg/kg.  No results are available on the total dietary intake in
    man, but it can be assumed that the dietary exposure of the general
    population will not exceed the ADI of 0.02 mg/kg body weight.

    2.2  Environmental Exposure and Fate

    On soil surfaces and in aqueous solutions at pH 5, lambda-cyhalothrin
    is degraded in sunlight with a half-life of approximately 30 days. The
    main degradation products are 3-(2-chloro-3,3,3-trifluoroprop1-enyl)-
    2-dimethylcyclopropane carboxylic acid, the amide derivative of
    cyhalothrin, and phenoxybenzoic acid.

    Degradation in soil occurs primarily through hydroxylation followed by
    cleavage of the ester linkage to give two main degradation products
    that are further degraded to carbon dioxide.  The initial half-lives
    are in the range of 22-82 days.

    Cyhalothrin and lambda-cyhalothrin are adsorbed on soil particles and
    are non-mobile in the environment.

    On plants, lambda-cyhalothrin degrades at a moderate rate (half-life
    up to 40 days) and the major constituent of the residue on plants is
    usually the parent compound.  Lower levels of metabolites, resulting
    from a range of hydrolytic and oxidative reactions, are also found.

    No data are available on actual levels of cyhalothrin and lambda-
    cyhalothrin in the environment, but with the current use pattern and
    low application rates, these are expected to be low.

    2.3  Uptake, Metabolism, and Excretion

    Metabolic studies have been carried out on the rat, dog, cow, and
    goat.  In the rat and dog, cyhalothrin was shown to be well absorbed
    after oral administration, extensively metabolized, and eliminated as
    polar conjugates in urine.  Cyhalothrin levels in rat tissues declined
    on cessation of exposure to the compound.  Residues in rat carcasses
    were low (< 5% of the dose after 7 days) and were found to be almost
    entirely due to cyhalothrin contained in fats.  Residues in fats were
    eliminated with a half-life of 23 days.

    After oral administration to lactating cows, cyhalothrin was rapidly
    eliminated, an equilibrium between ingestion and elimination being
    reached after 3 days;  27% of the dose was eliminated in the urine,
    50% in the faeces, and 0.8% in the milk.  Urinary material consisted
    entirely of ester cleavage metabolites and their conjugates; 60-70% of
    the faecal [14C]-material was identified as unchanged cyhalothrin.
    Tissue residues, 16 h after the last dose, were low, the highest
    concentrations being detected in fat.  The [14C]-residues in milk
    and fatty tissues were almost entirely unchanged cyhalothrin, no other
    component being detected.

    In all mammalian species investigated, cyhalothrin was extensively
    metabolized to the cyclopropane carboxylic acid and 3-phenoxybenzoic
    acid, as a result of ester cleavage, and eliminated as conjugates.

    In fish, the main residue in tissues consisted of unchanged
    cyhalothrin, with lower levels of the ester cleavage products.

    2.4  Effects on Organisms in the Environment

    Under laboratory conditions of constant toxicant concentrations,
    cyhalothrin and lambda-cyhalothrin were highly toxic for fish and
    aquatic invertebrates.  The 96-h LC50s for fish ranged between 0.2
    and 1.3 µg/litre; the 48-h LC50s for aquatic invertebrates ranged
    between 0.008 and 0.4µg/litre.

    Accumulation studies, conducted under laboratory conditions with
    constant concentrations, showed that rapid uptake takes place in fish
    (accumulation factor approximately 1000-2000).  However, in the
    presence of soil and suspended sediment, the bioaccumulation factors
    were greatly reduced - to 19 in the case of fish and 194 in the case
    of  Daphnia. When exposed fish and  Daphnia were placed in clean
    water, the residues declined rapidly, with half-lives of 7 days and
    1 day, respectively.  The concentrations of cyhalothrin and
    lambda-cyhalothrin that are likely to arise in water from normal
    agricultural application will be low.  Because the compound is rapidly
    adsorbed and degraded under natural conditions there will not be any
    practical problems concerning the accumulation of residues or the
    toxicity of cyhalothrin or lambda-cyhalothrin in aquatic species.

    Cyhalothrin and lambda-cyhalothrin are virtually non-toxic for birds;
    the single dose LD50 was greater than 3950 mg/kg in all species
    tested and the lowest 5-day dietary LD50 was 3948 mg/kg
    (lambda-cyhalothrin fed to 8-day-old mallard ducks).

    Under laboratory conditions, both cyhalothrin and lambda-cyhalothrin
    were toxic for honey-bees; the oral LD50 for lambda-cyhalothrin was
    0.97µg/bee.  However, in the field, the hazard is lower since current
    formulations have a repellent action that causes a suspension of
    foraging activity in the treated crop.  When foraging in the crop
    restarts, there is no significant increase in bee mortality.

    2.5  Effects on Experimental Animals and In Vitro Test Systems

    The acute oral toxicity of cyhalothrin is moderate in rats and mice
    and low in guinea-pigs and rabbits (rat LD50, 144-243 mg/kg; mouse
    LD50, 37-62mg/kg; guinea-pig LD50, >5000 mg/kg; rabbit LD50,
    >1000 mg/kg).  The acute oral toxicity of lambda-cyhalothrin is
    higher than that of cyhalothrin (rat LD50, 56-79 mg/kg; mouse
    LD50, 20 mg/kg).  The dermal toxicities are as follows: rat LD50,
    200-2000 mg/kg (cyhalothrin), 632-696mg/kg (lambda-cyhalothrin);
    rabbit LD50, >2000 mg/kg (cyhalothrin).  Cyhalothrin and
    lambda-cyhalothrin are Type II pyrethroids; clinical signs include
    ataxia, unsteady gait, and hyperexcitability.

    In the rabbit, cyhalothrin is a moderate eye irritant and
    lambda-cyhalothrin a mild eye irritant; both are mild skin irritants. 
    Cyhalothrin is not a skin irritant in the rat.  However, it is a
    moderate skin sensitizer in the guinea-pig. Lambda-cyhalothrin is not
    a skin sensitizer.

    In a 90-day feeding study in which rats were fed cyhalothrin at dose
    levels of up to 250 mg/kg diet, reduced body weight gain was observed
    in males at 250 mg/kg diet.  Marginal effects on mean erythrocyte
    volumes were noted in some treated groups, as well as some liver
    changes, which were considered to be an adaptive response.  In a
    90-day feeding study in which rats were fed lambda-cyhalothrin at dose
    levels of up to 250 mg/kg, reduced body weight gain was observed in
    both sexes at 250 mg/kg.  Some effects on  clinical chemistry were
    observed, as well as liver effects similar to those noted with
    cyhalothrin.  The no-observed-effect level was 50 mg/kg.

    In a 26-week oral study in which doses of up to 10 mg cyhalothrin/kg
    per day were administered to dogs, signs of pyrethroid toxicity were
    observed at 10 mg/kg per day.  The no-observed-effect level was
    2.5 mg/kg body weight per day.  A similar study was conducted in which
    up to 3.5 mg lambda-cyhalothrin/kg body weight per day was administered
    to dogs for 52 weeks.  Clinical signs of pyrethroid toxicity
    (neurological signs) were observed in all animals dosed with 3.5 mg/kg
    body weight per day.  The no-observed-effect level was 0.5 mg/kg per
    day.

    A 21-day study was conducted in which cyhalothrin in polyethylene
    glycol was applied dermally to rabbits at dose levels of up to
    1000 mg/kg per day.  Clinical signs of toxicity were observed in some
    animals at the highest dose level.  Slight to severe skin irritation
    was observed in all groups, including controls.

    Cyhalothrin was tested in two 104-week feeding studies, one on rats
    and one on mice.  In the rat study, no oncogenic effects were observed
    at dose levels up to 250 mg/kg diet (highest level tested).  The
    no-observed-effect level for systemic toxicity was 50 mg/kg diet
    (1.8 mg/kg body weight per day).  Decreased body weight gain was

    observed in both sexes at 250 mg/kg diet.  In the mouse study, no
    oncogenic effects were observed at dose levels up to 500 mg/kg diet
    (highest level tested).  Clinical signs of pyrethroid toxicity were
    observed at 100 and 500 mg/kg diet and reduced body weight gain was
    observed at 500 mg/kg diet.  The no-observed-effect level for systemic
    toxicity was 20 mg/kg diet (1.9 mg/kg body weight per day).  No
    histological evidence of damage to the nervous system was observed in
    either study.

    Cyhalothrin and lambda-cyhalothrin gave negative results in a range of
    in vivo and in vitro assays designed to detect gene mutations,
    chromosomal damage, and other genotoxic effects.  When orally
    administered to  the rat and rabbit during the period of major
    organogenesis, cyhalothrin was neither embryotoxic nor teratogenic at
    dose levels that elicited maternal toxicity (15 mg/kg per day for rats
    and 30 mg/kg per day for rabbits, both highest dose levels tested).

    A three-generation reproduction study was conducted on rats with
    cyhalothrin at dose levels of up to 100 mg/kg diet.  Minor decreases
    in litter size and small reductions in weight gain were seen at
    100 mg/kg diet; the no-observed-effect level for reproductive effects
    was 30 mg/kg diet.

    2.6  Effects on Human Beings

    No cases of accidental poisoning have been described.

    In manufacturing, formulation, laboratory work, and field usage,
    symptoms of subjective facial sensation have been reported.  This 
    effect generally lasts only a few hours, but occasionally persists for
    up to 72 h after exposure; medical examination has not revealed any
    neurological abnormalities.

    Subjective facial skin sensations, which may be experienced by people
    who handle cyhalothrin and lambda-cyhalothrin, are believed to be
    brought about by repetitive firing of sensory nerve terminals in the
    skin; they may be considered as an early warning signal indicating
    that overexposure of the bare skin has occurred.

    There are no indications that cyhalothrin and lambda-cyhalothrin, used
    under the present recommended conditions and application rates, will
    have any adverse effects on human beings. 

    3.  CONCLUSIONS AND RECOMMENDATIONS 

    3.1  Conclusions

     General population. The exposure of the general population to
    cyhalothrin and lambda-cyhalothrin is expected to be very low and is
    not likely to present a hazard under recommended conditions of use.

     Occupational exposure. With good work practices, hygiene measures,
    and safety precautions, cyhalothrin and lambda-cyhalothrin are
    unlikely to present a hazard to those occupationally exposed.

     Environment. It is unlikely that cyhalothrin, lambda-cyhalothrin, or
    their degradation products will attain levels of adverse environmental
    significance with recommended application rates.  Under laboratory
    conditions, cyhalothrin and lambda-cyhalothrin are highly toxic for
    fish, aquatic arthropods, and honey-bees. However, under field
    conditions, lasting adverse effects are not likely to occur under
    recommended conditions of use.

    3.2  Recommendations

    Although dietary levels from recommended usage are considered to be
    very low, confirmation of this through inclusion of cyhalothrin and
    lambda-cyhalothrin in monitoring studies should be considered.

    Cyhalothrin and lambda-cyhalothrin have been used for several years
    and cases of transient effects from occupational exposure have
    occurred.  Observation of human exposure should be maintained.

    4.  HUMAN HEALTH HAZARDS, PREVENTION AND PROTECTION, EMERGENCY ACTION

    4.1  Main Human Health Hazards, Prevention and Protection, First Aid

    Cyhalothrin is a synthetic pyrethroid insecticide of moderate acute
    toxicity (rat oral LD50, 144-243 mg/kg), unlikely to present an
    acute hazard in normal use.  Lambda-cyhalothrin is slightly more toxic
    (rat oral LD50, 56-79 mg/kg).  No cases of poisoning have been
    described in the general population and none from occupational
    exposure.  The results of experimental animal studies suggest that,
    following massive overexposure or accidental ingestion, neurological
    signs and symptoms, such as tremors and convulsions, could occur.

    The human health hazards associated with certain types of exposure to
    cyhalothrin, together with preventive and protective measures and
    first-aid recommendations, are listed in the International Chemical
    Safety Card (section 6).

    4.1.1  Advice to physicians

    No specific antidote is known.  A hazard with liquid formulations is
    aspiration of the solvent into the lungs, resulting in chemical
    pneumonitis.  Therefore, do not induce vomiting; empty stomach only on
    specialist advice using appropriate equipment.  Treat symptomatically. 
    In case of convulsions, diazepam should be given slowly intravenously
    or rectally in an appropriate dose (10 or 20 mg in an adult), and
    repeated if necessary.

    4.1.2  Health surveillance advice

    A pre-employment and an annual general medical examination are advised
    for regularly exposed workers.  Occurrence of "facial skin sensations"
    is an indication of exposures that should be corrected.

    4.2  Explosion and Fire Hazards

    Some solvents in pyrethroid formulations are highly flammable.  Use
    dry powder, carbon dioxide, alcohol-resistant foam, sand, or earth for
    dealing with fires.  Do not use water.  Cool nearby drums with water
    spray.  If pyrethroid products are involved in a major fire or in a
    fire involving other products, advise the fire service that protective
    clothing and breathing apparatus should be worn.  Also, warn the
    authorities that pyrethroids are highly toxic for fish, and that the
    use of water should be confined to the cooling of unaffected stock,
    thus avoiding accumulation of polluted run-off from the site. 

    4.3  Storage

    Store technical material and formulations away from heat, under lock
    and key, and out of reach of children, animals, and unauthorized
    personnel.  Store in an area designated for pesticide storage. 
    Prevent spills from leaking into watercourses.

    Store away from foodstuffs and animal feed.

    4.4  Transport

    Pyrethroids are classified as harmful or low hazard for transport
    purposes.  Formulations based on flammable solvents may be subject to
    local transport controls.  Ensure that containers are sound and that
    labels are securely fixed and undamaged before dispatch.  Comply with
    local transport regulations.

    Do not load together with foodstuffs and animal feed.

    4.5  Spillage and Disposal

    4.5.1  Spillage

    Empty any product remaining in damaged or leaking containers into a
    clean empty drum and affix the correct label.

    Absorb spillage with lime, damp sawdust, sand, or earth and dispose of
    safely (see below).  If spillage is large, contain it by building a
    barrier of earth or sandbags.

    Decontaminate empty, damaged, or leaking containers with a 10% sodium
    carbonate solution added at the rate of at least 1 litre per 20-litre
    drum.  Puncture containers to prevent reuse.

    4.5.2  Disposal

    Waste containing cyhalothrin or lambda-cyhalothrin should be burnt in
    a suitable high-temperature incinerator fitted with a high-efficiency
    gas scrubbing system.  Where no incinerator is available, contaminated
    absorbents or surplus products should be decomposed by hydrolysis at
    pH12 or above.  Contact with a suitable hydrolysing agent is required
    to ensure degradation of the active ingredient to a safe
    concentration.

    For emulsifiable material:         5% sodium hydroxide (caustic soda)
                                       solution or saturated (7-10%)
                                       sodium carbonate (washing soda)
                                       solution can be used

    For non-emulsifiable material:     use a 1:1 mixture (by volume) of
                                       either of the above solutions and a
                                       water/oil soluble solvent, such as
                                       denatured alcohol, monoethylene
                                       glycol, hexylene glycol, or
                                       2-propanol

    Cover the material with a hydrolysing agent and leave to stand for 7
    days.  Before disposal of the resultant waste, the material must be
    analysed to ensure that the active ingredient has been degraded to a
    safe level.

    Never pour untreated waste or surplus products into public sewers or
    where there is any danger of run-off or seepage into streams,
    watercourses, open waterways, ditches, fields with drainage systems,
    or the catchment areas of boreholes, wells, springs, or ponds.

    5.  HAZARDS FOR THE ENVIRONMENT AND THEIR PREVENTION

    Cyhalothrin and lambda-cyhalothrin are very toxic for fish, aquatic
    invertebrates, and honey-bees but, because very low exposure levels
    normally occur, this would only cause a problem in the case of
    spillage.  The toxicity for birds is low.

    With recommended techniques and rates of application, it is unlikely
    that cyhalothrin and lambda-cyhalothrin and their degradation products
    will attain levels of adverse environmental significance.

    Avoid spraying over bodies of water.  Do not contaminate ponds,
    waterways, or ditches with the product or used containers.

    6.  INTERNATIONAL CHEMICAL SAFETY CARD

     This card should be easily available to all health workers concerned
     with, and users of, cyhalothrin and lambda-cyhalothrin. It should be
     displayed at, or near, entrances to areas where there is potential
     exposure to cyhalothrin and lambda-cyhalothrin, and on processing
     equipment and containers.  The card should be translated into the
     appropriate language(s).  All persons potentially exposed to the
     chemicals should also have the instructions on the chemical safety
     card clearly explained.

     Space is available on the card for the insertion of the National
     Occupational Exposure Limit, the address and telephone number of the 
     National Poison Control Centre, and for local trade names.


        CYHALOTHRIN
    (C23H19C1F3NO3)

    CAS chemical name:  (R+S)-alpha-cyano-3-(phenoxyphenyl)methyl(1 S+1 R)-
     cis-3( z-2-chloro-3,3,3-trifluoroprop-1-enyl)-2,2-dimethylcyclopropane carboxylate

    CAS registry number:     cyhalothrin: 68085-85-8 
                             lambda-cyhalothrin: 91465-08-6 

                                                                                                                                         

    PHYSICAL PROPERTIES                CYHALOTHRIN           LAMBDA-                OTHER CHARACTERISTICS
                                                                                    CYHALOTHRIN
                                                                                                                                         

    Relative molecular mass            449.9                 449.9                  Technical cyhalothrin is a yellow-
    Melting point (°C)                 -                     49.2                   brown viscous liquid with a mild 
    Decomposition (°C)                 > 275                 > 275                  odour; it consists of selected 
    Water solubility                   4 × 10-3 mg/litre     5 × 10-3 mg/litre      isomers of a chlorotrifluoro derivative 
    Solubility in organic solvent      soluble               soluble                of chrysanthemic acid; it is stable
    n-Octanol water-partition                                                           to light and at temperatures below 
      coefficient log Pow (20°C)       6.9                   7.0                    220°C 

    Density                            1.25 g/ml             1.33 g/ml              It is a pyrethroid insecticide used
    Vapour pressure                                                                 as a stomach and contact insecticide
      (kPa at 20°C)                    1 × 10-9              2 × 10-10              in agriculture; it is also used in public 
      (kPa at 80°C)                    4 × 10-6              3 × 10-6               and animal health

                                                                                                                                         

    HAZARDS/SYMPTOMS                        PREVENTION AND PROTECTION                    FIRST AID
                                                                                                                                         

    SKIN: Irritating to skin;               Proper application techniques;               Remove contaminated clothing; 
    facial skin sensations                  proper skin protection; clean                wash skin with water and soap
                                            protective equipment before re-use

    EYES: Irritating to eyes                Wear face shield, goggles                    Flush with clean water for a least
                                                                                         15 minutes

    INHALATION: Irritation of               Avoid inhalation of fine dust and            Fresh air
    upper respiratory system                mist

    INGESTION: Unlikely to be               Do not eat, drink, or smoke during
    a significant occupational              work; wash hands before eating,
    hazard                                  drinking, or smoking

    Accidental or deliberate                                                             Obtain medical attention 
    ingestion could lead to                                                              immediately; if breathing has 
    neurological signs and symptoms,                                                     stopped, apply artificial
    such as tremors and convulsions                                                      respiration

    A hazard of ingested liquid                                                          Do not induce vomiting
    formulations is aspiration into 
    the lungs

    ENVIRONMENT: Very toxic                 Do not contaminate ponds,                    Effect on ponds can be minimized by 
    for fish and honey-bees                 waterways, or ditches with                   by the addition of soil 
                                            product or used containers

                                                                                                                                         
    SPILLAGE                                STORAGE                                      FIRE AND EXPLOSION
                                                                                                                                         

    Absorb spillage with lime, damp         Store in locked, well-ventilated             Some liquid formulations may be highly
    sawdust, sand, or earth; sweep up,      storeroom, away from feed                    flammable; use dry powder, carbon
    place in closed container and           and foodstuffs, children, and                dioxide, or alcohol-resistant foam; cool
    dispose of safely; avoid contamination  unauthorized personnel                       nearby drums with water spray
    of personnel, ponds, and waterways

                                                                                                                                         

    WASTE DISPOSAL
                                                                                                                                         

    Burn in high-temperature                National Occupational Exposure Limit:
    incinerator with effluent scrubbing;
    alternatively, treat with 5% caustic
    soda as a hydrolysing agent for 7 
    days; comply with local regulations     National Poison Control Centre:

                                            Local trade names:                           

    FIGURE 1
                                                                                                                                         
    
    7.  CURRENT REGULATIONS, GUIDELINES, AND STANDARDS

    The information given in this section has been extracted from the
    International Register of Potentially Toxic Chemicals (IRPTC) legal
    file and other United Nations sources.  The intention is to give the
    reader a representative, but not exhaustive, overview of current
    regulations, guidelines, and standards.

    The reader should be aware that regulatory decisions about chemicals
    taken in a certain country can only be fully understood in the
    framework of the legislation of that country. Furthermore, the
    regulations and guidelines of all countries are subject to change and
    should always be verified with the appropriate regulatory authorities
    before application.

    7.1  Previous Evaluations by International Bodies

    Cyhalothrin was discussed by the FAO/WHO Joint Meeting on Pesticide
    Residues (JMPR) in 1984 and 1986.  The JMPR established an acceptable
    daily intake (ADI) for cyhalothrin of 0-0.02 mg/kg body weight (1984),
    and proposed a temporary MRL (maximum residue limit) of 0.2 mg/kg on
    pome fruit and cabbages and 0.02 mg/kg on cottonseed, cottonseed oil,
    and potatoes (the level refers to the sum of cyhalothrin isomers)
    (1988).

    7.2  Exposure Limit Values

    The values recommended by the JMPR are mentioned above.

    7.3  Specific Restrictions

    No information available.

    7.4  Labelling, Packaging, and Transport

    The United Nations Committee of Experts on the Transportation of
    Dangerous Goods classifies pyrethroids in:

    - Hazard class 6.1:           poisonous substance

    - Packing group III:          a substance presenting a relatively low
                                  risk of poisoning in transport.

    The label should be as follows:

    FIGURE 2

    The bottom half of the label should bear the inscription:

          Harmful, stow away from foodstuffs.

    European Community legislation requires labelling as a dangerous
    substance, using the symbol: 

    FIGURE 3

    The label must read:

          Harmful by inhalation, in contact with skin and if swallowed;
          keep out of reach of children; keep away from food, drink, and
          animal feeding stuff.

    7.5  Waste Disposal

    In some countries, specific permits are required for the discharge of
    pyrethroids from any point source into surface or underground waters. 
    Detailed conditions before such discharges are permitted are laid
    down.

    BIBLIOGRAPHY

    FAO  (1985a)  Guidelines for the packaging and storage of pesticides,
    Rome, Food and Agriculture Organization of the United Nations.

    FAO  (1985b)  Guidelines for the disposal of waste pesticides and
     pesticide containers on the farm, Rome, Food and Agriculture
    Organization of the United Nations.

    FAO  (1985c)  Guidelines on good labelling practice for pesticides,
    Rome, Food and Agriculture Organization of the United Nations.

    FAO  (1986)  International code of conduct on the distribution and use
     of pesticides, Rome, Food and Agriculture Organization of the United
    Nations.

    FAO/WHO  (1986)  Guide to Codex recommendations concerning pesticide
     residues. Part 8. Recommendations for methods of analysis of
     pesticide residues, 3rd ed., Rome, Codex Committee on Pesticide
    Residues.

    GIFAP  (1982)  Guidelines for the safe handling of pesticides during
     their formulation, packing, storage and transport, Brussels,
    Groupement International des Associations Nationales des Fabricants de
    Produits Agrochimiques.

    GIFAP  (1983)  Guidelines for the safe and effective use of
     pesticides, Brussels, Groupement International des Associations
    Nationales des Fabricants de Produits Agrochimiques.

    GIFAP  (1984)  Guidelines for emergency measures in cases of pesticide
     poisoning, Brussels, Groupement International des Associations
    Nationales des Fabricants de Produits Agrochimiques.

    GIFAP (1987)  Guidelines for the safe transport of pesticides,
    Brussels, Groupement International des Associations Nationales des
    Fabricants de Produits Agrochimiques.

    IARC  (1972-present)  IARC monographs on the evaluation of
     carcinogenic risk of chemicals to man, Lyons, International Agency
    for Research on Cancer.

    IRPTC  (1985)  IRPTC file on treatment and disposal methods for waste
     chemicals, Geneva, International Register of Potentially Toxic
    Chemicals, United Nations Environment Programme.

    IRPTC  (1987)  IRPTC legal file 1986, Geneva, International Register
     of Potentially Toxic Chemicals, United Nations Environment
    Programme.

    PLESTINA, R.  (1984)  Prevention, diagnosis, and treatment of
     insecticide poisoning, Geneva, World Health Organization
    (unpublished document WHO/VBC/84.889).

    SAX, N.I.  (1984)  Dangerous properties of industrial materials, New
    York, Van Nostrand Reinhold Company, Inc.

    UNITED NATIONS  (1986)  Recommendations on the transport of dangerous
     goods, 4th ed., New York, United Nations.

    US NIOSH/OSHA  (1981)  Occupational health guidelines for chemical
     hazards, 3 Vols. Washington DC, US Department of Health and Human
    Services, US Department of Labor (Publication No. DHHS(NIOSH) 01-123).

    WHO  (In press, 1990)  EHC No. 99: Cyhalothrin, Geneva, World Health
    Organization. 

    WHO  (1988)  The WHO recommended classification of pesticides by
     hazard and guidelines to classification 1988-89, Geneva, World
    Health Organization (unpublished document WHO/VBC/88.953).

    WORTHING, C.R. & WALKER, S.B.  (1983)  The pesticide manual, 7th ed.,
    Lavenham, Lavenham Press Limited, British Crop Protection Council.

    


    See Also:
       Toxicological Abbreviations