Health and Safety Guide No. 32






    This is a companion volume to Environmental Health Criteria 96:

    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)

    ISBN 92 4 154353 1
    ISSN 0259

    World Health Organization 1989

    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.

    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.



         1.1. Identity
         1.2. Physical and chemical properties
         1.3. Analytical methods
         1.4. Production and uses

         2.1. Human exposure
         2.2. Environmental fate
         2.3. Kinetics and metabolism
         2.4. Effects on organisms in the environment
         2.5. Effects on experimental animals and  in vitro test
         2.6. Effects on human beings

         3.1. Conclusions
         3.2. Recommendations

         4.1. 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



         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



    The Environmental Health Criteria (EHC) documents produced by the
    International Programme on Chemical Safety include an assessment of
    the effects on the environment and human health from exposure to a
    chemical or combinations of chemicals, or to 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 people in the occupational health
    services, ministries, governmental agencies, industry, and trade
    unions, who are involved in the safe use of chemicals and the
    prevention of environmental health hazards, and also workers who would
    like more information on this topic.  An attempt has been made to use
    only terms that are familiar to the user.  However, sections 1 and 2
    inevitably contain some technical terms.  A bibliography has been
    included for readers who would like to have further background

    Revision of the information in this Guide will take place in due
    course.  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



    1.1  Identity

    Common name:                       d-Phenothrin

    Chemical structure:


    Molecular formula:                 C23H26O3

    CAS chemical name:                 Cyclopropanecarboxylic acid, 2,2-
                                       methyl ester

    CAS registry number:               26002-80-2 (racemic)

    RTECS registry number:             GZ 1975000 (racemic)
                                       GZ 2002000 (d-phenothrin)

    Common synonyms and trade names:   Sumithrin, S-2539 Forte

    Relative molecular mass:           350.49

    d-Phenothrin is a synthetic pyrethroid insecticide.  Racemic
    phenothrin was invented in 1969.  It is a mixture of four
    stereoisomers.  d-Phenothrin is a mixture of the two isomers that have
    the highest activity and is the only technical product commercially
    available.  The technical grade is 92.5-94.5% pure.

    1.2  Physical and Chemical Properties

    Some physical and chemical properties of d-phenothrin are given in the
    International Chemical Safety Card (section 6).  Technical grade
    d-phenothrin is a colourless or pale yellow liquid.  It has a low
    solubility in water, but is soluble in organic solvents such as
    acetone, xylene, and hexane.  It is fairly stable in air, but unstable
    to light, although it is not photodegraded as rapidly as natural
    pyrethrins. It is also unstable under alkaline conditions.

    1.3  Analytical Methods

    Residue analysis is done with high-performance liquid chromatography
    with a UV detector, the minimum detectable concentration being
    0.05 mg/kg.  Gas chromatography with a flame ionization detector is
    used to analyse technical products.

    1.4  Production and Uses

    d-Phenothrin has been used since 1977.  It is estimated that 70 to
    80 tonnes of d-phenothrin are used annually worldwide.  d-Phenothrin
    is used primarily to control household insects and insects endangering
    public health, to protect stored grains, alone or in combination with
    other insecticides and/or synergists, and to control lice in human
    beings.  It is formulated as an aerosol, in oil and dust formulations,
    or as an emulsifiable concentrate.  When used to control lice, it is
    formulated as powders, shampoos, and lotions.


    2.1  Human Exposure

    Air levels from conventional household aerosol spraying with
    d-phenothrin are not expected to exceed 0.5 mg/m3.  Residues of up
    to 4 mg/kg might be present in stored wheat.  In flour, these 
    residues  decrease to 0.8 mg/kg after milling and to 0.6 mg/kg after

    To control lice, d-phenothrin (32 mg/person) is usually applied to the
    hair once a day every 3 days for a maximum of 9 days. No data are
    available on occupational exposure to d-phenothrin.

    Exposure of the general population to d-phenothrin is expected to be
    very low, but precise data are not available.

    2.2  Environmental Fate

    Phenothrin degrades readily on plants and other surfaces and has a
    half-life of <1 day.  There is little translocation of d-phenothrin
    and its degradation products to the untreated parts of the plants. 
    Limited uptake of radiolabelled products into bean plants took place
    from soils treated with 14C-phenothrin.  When soils are treated with
    [1R, trans]-or [1R, cis]-phenothrin (1 mg/kg), both isomers
    decompose rapidly having initial half-lives of 1 to 2 days.  Under
    flooded conditions, the degradation is much slower, with initial
    half-lives of 2 to 4 weeks for [1R, trans]- phenothrin and 1 to 2
    months for [1R, cis]-phenothrin.  Very little movement (approximately
    2%) of  trans- and  cis-phenothrin is observed through soil columns
    when leaching is begun immediately or 14 days after treatment with the

    In general, the degradative processes that occur in the environment
    lead to less toxic products.

    2.3  Kinetics and Metabolism

    After rats were given single or repeated oral exposure or dermal
    treatment with radiolabelled phenothrin, radiolabels were rapidly and
    almost completely excreted in the urine and faeces (3-7 days).  The
    major metabolic pathways of both  trans- and  cis-phenothrin in rats
    were ester cleavage and oxidation at the 4'-position of the alcohol
    moiety or the isobutenyl group of the acid moiety. Ester-cleaved
    metabolites (excreted mainly in the urine) were the principal products
    of the trans isomer, whereas ester-form metabolites (excreted mainly
    in the faeces) were mostly formed from the cis isomer.

    2.4  Effects on Organisms in the Environment

    Phenothrin has been tested only on a few groups of non-target
    organisms and only on a few species within each group.  The range of
    96-h LC50 values for racemic phenothrin and (1R)-stereoisomers in
    fish ranged from 17 to 200 g/litre.  In a single study on aquatic
    invertebrates, 3-h LC50 values for  Daphnia pulex were 25 000
    to 50 000 g/litre for all isomers and racemic phenothrin.

    A single field study in which phenothrin was applied to ponds showed
    no effect on aquatic arthropods.

    Toxicity to birds is low with an acute oral LD50 for bobwhite quail
    of >2500 mg/kg body weight, and a dietary LC50 for mallard duck and
    bobwhite quail of >5000 mg/kg diet.

    Since phenothrin breaks down rapidly in sunlight and is used primarily
    on stored grain, environmental exposure is expected to be very low.
    Therefore, adverse effects on the environment are extremely

    2.5  Effects on Experimental Animals and In Vitro Test Systems

    The acute toxicity of d-phenothrin is extremely low with LD50 values
    of >5000 mg/kg body weight in rats and mice (through the oral,
    subcutaneous, dermal, and intraperitoneal routes), and LC50 values
    of >3760 mg/m3 in rats (through the inhalation route). 
    d-Phenothrin causes a poisoning syndrome which may include tremor,
    ataxia, hyperexcitability, prostration, or paralysis.  These symptoms,
    and the results of electrophysiological studies of cockroach cercal
    sensory nerves, classify d-phenothrin as a Type I pyrethroid.

    When rats were exposed to d-phenothrin by inhalation at concentrations
    of up to 210 mg/m3 for 4 h/day for 4 weeks, or orally for 5
    consecutive days at a dose of 5000 mg/kg body weight, no adverse
    toxicological effects were observed.

    Several feeding studies of phenothrin (racemic or d-phenothrin, from
    200 to 10 000 mg/kg diet) in rats and mice, with exposure periods from
    6 months to 2 years, were performed. No-observed-effect levels (NOELs)
    in these studies ranged from 300 to 1000 mg/kg diet which correspond
    to approximately 40 to 160 mg/kg body weight per day. In two studies
    studies in dogs in which d-phenothrin was given in doses from 100 to
    3000 mg/kg diet, with exposure periods of 26 to 52 weeks, NOELs of
    300 mg/kg diet, corresponding to 7-8 mg/kg body weight per day, were

    d-Phenothrin is not mutagenic in a variety of  in vivo and  in vitro
    test systems that studied gene mutations, DNA damage, DNA repair, and
    chromosomal effects.

    In 2-year studies, d-phenothrin was not oncogenic in rats and mice at
    dietary levels of up to 3000 mg/kg diet.

    Neither teratogenicity nor embryotoxicity was observed in fetuses of
    rabbits and mice given oral d-phenothrin at up to 1000 and 3000 mg/kg
    body weight, respectively.  In a two-generation reproduction study in
    rats, the NOEL was 1000 mg/kg diet.

    Rats exposed to very high doses of d-phenothrin at a concentration of
    up to 3760 mg/m3 for 4 h by inhalation, or to a dose of 5000 mg/kg
    body weight per day for 5 days orally, showed no myelin degeneration
    or axon disruption in the sciatic nerve.

    2.6  Effects on Human Beings

    Although d-phenothrin has been used for more than 10 years, there have
    been no reports of poisoning in human beings.

    There are no indications that d-phenothrin, when used as recommended,
    will have an adverse effect on human beings.


    3.1  Conclusions

    (a)  General population: The exposure of the general population to
    d-phenothrin is expected to be very low and is not likely to be a
    hazard when used as recommended.

    (b)  Occupational exposure: With reasonable work practices, hygiene
    measures, and safety precautions, d-phenothrin is unlikely to be an
    occupational hazard.

    (c)  Environment: Since d-phenothrin breaks down rapidly in sunlight
    and is used principally on stored grain, environmental exposure is
    expected to be very low. Therefore, environmental effects of the
    compound are extremely improbable.

    3.2  Recommendations

    When d-phenothrin is used as recommended, exposure levels are expected
    to be very low. However, monitoring studies should be continued.


    4.1  Human Health Hazards, Prevention and Protection, First Aid

    d-Phenothrin is a synthetic pyrethroid insecticide. There have been no
    cases of poisoning reported in the general population or from
    occupational exposure. Experimental studies in animals suggest that
    neurological signs and symptoms, tremors, and ataxia could occur after
    massive over-exposure or accidental ingestion.

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

    4.1.1  Advice to physicians

    There is no specific antidote for d-phenothrin poisoning. Treat
    symptomatically.  Chemical pneumonitis resulting from aspiration of
    the solvent into the lungs occurs when liquid formulations are

    4.1.2  Health surveillance advice

    Depending on the degree of exposure, general medical examinations
    should be done annually.

    4.2  Explosion and Fire Hazards

    Some solvents in pyrethroid formulations are highly flammable.  DO NOT
    USE WATER to extinguish fires.  Use dry powder, carbon dioxide, or
    alcohol-resistant foam, sand, or earth.  Cool nearby drums with water

    If pyrethroid products are involved in a major fire, advise the fire
    service to wear protective clothing and breathing apparatus.  Inform
    the fire service and other relevant authorities that pyrethroids are
    toxic for fish and that water should be used only to cool unaffected
    stock. In this way, the accumulation of polluted run-off from the site
    is prevented.

    4.3  Storage

    Store technical material and formulations away from heat, in a locked,
    well-ventilated area, preferably without drains, designated for
    insecticide storage only.  Keep out of reach of children, unauthorized
    personnel, and away from animals.

    Store away from food and animal feed.

    4.4  Transport

    For transport purposes, pyrethroids are classified as "harmful" or as
    "low hazard".  Formulations made with flammable solvents may be
    subject to local transport controls.  Before transport, ensure that
    containers are sound and that labels are securely fixed and not
    damaged.  Comply with local transport regulations.

    Do not transport in compartments that contain food and animal feed.

    4.5  Spillage and Disposal

    4.5.1  Spillage

    Keep spectators away from leaking or spilled product.  Prohibit
    smoking and the use of naked flames in the immediate vicinity.

    Avoid exposure by wearing appropriate protective clothing and masks.

    Transfer any product remaining in damaged or leaking containers into a
    clean, empty drum, and label the drum.

    Absorb spillage and cover contaminated area with lime, damp sawdust,
    sand, or earth, and place in a secure container for safe disposal (see
    section 4.5.2).  Contain a large spillage by building a barrier of
    earth or sandbags.

    Prevent liquid from spreading to other cargo, vegetation, or waterways
    by containing it with the most readily available barrier material,
    e.g., earth or sand.

    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 that contains d-phenothrin should be burnt in an appropriate
    high-temperature incinerator with effluent scrubbing.  If no
    incinerator is available, contaminated absorbents or surplus products
    should be decomposed by hydrolysis at pH 12 or above.  Contact with a
    suitable hydrolysing agent is required to ensure degradation of the 
    active ingredient to a safe level.

    For emulsifiable material, use 5% sodium hydroxide (caustic soda)
    solution or saturated (7-10%) sodium carbonate (washing soda)

    For non-emulsifiable material, use a 1:1 mixture (by volume) of
    caustic soda or washing soda (as above) and a water/oil soluble
    solvent such as denatured alcohol, monoethylene glycol, hexylene
    glycol, or isopropylalcohol.

    Cover the material with a hydrolysing agent and let it stand for 7
    days.  Before disposal, the waste 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 to streams,
    water-courses, open waterways, ditches, fields with drainage systems,
    or to the catchment areas of boreholes, wells, springs, or ponds.


    When  used  as  recommended, it is very unlikely that either
    d-phenothrin or its degradation products will reach levels of
    environmental significance.  d-Phenothrin is toxic for fish, but due
    to the very low exposure levels that could occur, it will only cause a
    problem if spilled.

    Do not dispose of d-phenothrin or its containers in ponds, waterways,
    or ditches.


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

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


    CAS chemical name: Cyclopropanecarboxylic acid, 2,2-dimethyl-3-(2-methyl-
    1-propenyl)-(3-phenoxyphenyl)methyl ester

    CAS registry no: 26002-80-2
    Molecular formula: C23H26O3
    RTECS registry no: GZ2002000


    PHYSICAL PROPERTIES                                                   OTHER CHARACTERISTICS

    Physical state                     liquid                             Phenothrin is a mixture of four stereo-isomers;
    Colour                             pale yellow to yellow brown        d-Phenothrin is a mixture of the
    Relative molecular mass            350.49                             two most active isomers. The technical
    Water solubility (25 C)           2 mg/litre                         grade is 92.5-94.5% pure. d-Phenothrin is
    Solubility in organic solvents     solublea                           fairly stable in air but unstable to light
    Density                            d25 1.058-1.061                    and under alkaline conditions. It is a synthetic
                                                                          pyrethroid, mainly used alone or in
    Vapour pressure (20 C)            0.16 mPa                           combination as a household insecticide and
                                                                          for public health. It is used mostly in
                                                                          aerosol form.


    a Hexane (>1 mg/kg), acetone, methanol, xylene.


    HAZARDS/SYMPTOMS                        PREVENTION AND PROTECTION                    FIRST AID

    SKIN: Some formulations may             Use proper application techniques            Remove contaminated clothing; wash
    cause skin irritation                   and proper skin protection                   skin with soap and water

    EYES: Splashes may cause                Wear face shield or goggles                  Flush immediately with clean water
    irritation                                                                           for at least 15 min

    INHALATION: Dust or droplets            Do not inhale fine dust and mist             Fresh air
    may cause irritation

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

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

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

    ENVIRONMENT: Toxic for                  Do not contaminate ponds, waterways,
    fish                                    or ditches with product or used


    SPILLAGE                                STORAGE                                      FIRE AND EXPLOSION

    Absorb spillage with lime, damp         Store in locked, well-ventilated             DO NOT USE WATER; some liquid
    sawdust, sand, or earth; sweep          storeroom, out of reach of children          formulations may be highly flammable;
    up, place in closed container,          and unauthorized personnel, and              use dry powder, carbon dioxide, or
    and dispose of safely; do not           away from food and animal feed.              alcohol-resistant foam; cool nearby
    contaminate personnel, ponds,                                                        drums with water spray
    or waterways


    WASTE DISPOSAL                          NATIONAL INFORMATION

    Burn in high-temperature                National Occupational Exposure Limit:
    incinerator with effluent scrubbing
    Or, treat with 5% caustic soda          National Poison Control Centre:
    as a hydrolysing agent; comply
    with local regulation                   Local trade names:

    FIGURE 1


    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.  It is a representative but
    non-exhaustive overview of current regulations, guidelines, and

    Regulations and guidelines about chemicals can be fully understood
    only within the framework of a country's legislation, and are always
    subject to change.  Therefore, they should always be verified with the
    appropriate authorities.

    7.1  Previous Evaluations by International Bodies

    The Joint FAO/WHO Expert Committee on Pesticide Residues (JMPR)
    evaluated d-phenothrin at its meetings in 1979, 1980, 1984, and 1988.

    In 1988, an acceptable daily intake (ADI) of 0-0.07 mg/kg body weight
    was established.

    The Division of Vector Biology and Control, World Health Organization,
    classified phenothrin as a technical product that is not likely to
    present an acute hazard when used as recommended (WHO, 1988).

    7.2  Exposure Limit Values

    Some exposure limit values are given in the table that follows.

    7.3  Specific Restrictions

    No information is 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 with a relatively low risk of
         poisoning during transport.



    Medium      Specification       Country/            Exposure limit description                   Value                Effective
                                    organization                                                                          date

    FOOD        Intake from         FAO/WHO             Temporary acceptable daily intake            0.04 mg/kg           1985
                                                        (TADI) (mg/kg body weight for

    FOOD        Plant residues      FAO/WHO             Temporary maximum residue limit
                                                        - Wheat bran (unprocessed)                   15 mg/kg             1980

                                    FAO/WHO             Maximum residue limit (MRL)                   5 mg/kg             1980
                                                        (cereal grains)

    The label should be as follows:

    FIGURE 2

    The 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, permits are required to empty pyrethroids into


    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

    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

    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 for Potentially Toxic
    Chemicals, United Nations Environment Programme.

    IRPTC  (1987)  IRPTC legal file 1983. 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 Departmnent of Labor (Publication No. DHSS (NIOSH)

    WHO  (In press)  Environmental Health Criteria No. 96: d-Phenothrin.
    Geneva, World Health Organization.

    WHO  (1988)  The WHO recommended classification of pesticides by
     hazard. 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
       Phenothrin, d- (EHC 96, 1990)
       Phenothrin, d- (Pesticide residues in food: 1988 evaluations Part II Toxicology)