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    IPCS INTERNATIONAL PROGRAMME ON CHEMICAL SAFETY
    Health and Safety Guide No. 5

    2,4-DICHLOROPHENOXYACETIC (2,4-D)
    HEALTH AND SAFETY GUIDE






    UNITED NATIONS ENVIRONMENT PROGRAMME

    INTERNATIONAL LABOUR ORGANISATION

    WORLD HEALTH ORGANIZATION




    WORLD HEALTH ORGANIZATION, GENEVA 1987

    This is a companion volume to Environmental Health Criteria 29:
    2,4-Dichlorophenoxyacetic Acid (2,4-D)

    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

    ISBN 92 4 154329 9
    ISSN 0259-7268

    The World Health Organization welcomes requests for permission to
    reproduce or translate its publications, in part or in full. 
    Applications and enquiries should be addressed to the Office of
    Publications, World Health Organization, Geneva, Switzerland, which
    will be glad to provide the latest information on any changes made to
    the text, plans for new editions, and reprints and translations
    already available.

    (c) World Health Organization 1987

    Publications of the World Health Organization enjoy copyright
    protection in accordance with the provisions of Protocol 2 of the
    Universal Copyright Convention.  All rights reserved.

    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

    IPCS

    HEALTH AND SAFETY GUIDE FOR 2,4-DICHLOROPHENOXYACETIC ACID (2,4-D)

    INTRODUCTION

    HOW TO USE THE GUIDE

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

    2. SUMMARY AND EVALUATION
         2.1. Exposure to 2,4-D
         2.2. Uptake, metabolism, and excretion
         2.3. Effects on animals
         2.4. Effects on human beings
         2.5. Estimated intake of 2,4-D

    3. CONCLUSIONS

    4. HEALTH HAZARDS FOR MAN, PREVENTION AND PROTECTION, EMERGENCY
         ACTION
         4.1. Main hazards for man, prevention and protection,
               first aid
               4.1.1. Prevention and protection, first aid
         4.2. Advice to physicians
         4.3. Health surveillance advice
         4.4. Safe handling advice
         4.5. Explosion and fire hazards
         4.6. Storage
         4.7. Transport
         4.8. Spillage and disposal
               4.8.1. Spillage
               4.8.2. Disposal (based on the IRPTC waste disposal
                       file)

    5. INTERNATIONAL CHEMICAL SAFETY CARD

    6. HAZARDS FOR THE ENVIRONMENT AND THEIR PREVENTION

    7. CURRENT REGULATIONS, GUIDELINES, AND STANDARDS
         7.1. Exposure limit values
         7.2. Specific restrictions
         7.3. Labelling, packaging, and transport
         7.4. Waste disposal
         7.5. Other measures

    

    INTRODUCTION

    The International Programme on Chemical Safety is responsible for the
    publication of a series of Environmental Health Criteria documents,
    each of which assesses the existing information on the relationship
    between exposure to a specific chemical, mixture of chemicals, or
    combination of chemicals and physical and biological agents, and man's
    health and the integrity of the environment. The documents provide
    guidelines for setting exposure limits consistent with the protection
    of human health and the environment.

    To facilitate the application of these guidelines in national chemical
    safety programmes, "Health and Safety Guides" are being prepared,
    highlighting the information contained in the documents for those who
    need to know the health and environmental issues involved, but not the
    scientific details. The Guides include advice on preventive and
    protective measures and emergency action.

    Review and revision of the information in this Health and Safety Guide
    will take place in due course, and the eventual aim is to use
    standardized terminology. We should be grateful if you would help by
    telling us of any difficulties encountered in using the information in
    this guide.

    Comments please, addressed to:

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

    HOW TO USE THE GUIDE

    All people in the work-place environment should be given the relevant
    written information in this book, supplemented by a clear, personal
    explanation to ensure that they are fully aware of the dangers and the
    current courses of protective and emergency action.

    The International Chemical Safety Card should be displayed as directed
    and its contents clearly explained to all working personnel.

    Medical staff should be fully conversant with the medical information
    to ensure they can act rapidly and efficiently in an emergency.

    Posters should be used to give impact to basic safety measures.

    Further copies of the Health and Safety Guide and, for those requiring
    more detailed scientific information, the relevant Environmental
    Health Criteria publication, are available to order.

    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

    Chemical formula:        C8H6Cl2O3

    Chemical structure:

    CHEMICAL STRUCTURE

    Common trade namesa:     Aaherba-2,4-D; Agriben; Agrotect; Amidox;
                             Amoxone; Aqua-Kleen; BH 2,4-D; BD; Brabant;
                             2,4-D Amine; Chimac 2,4-D Amine; D 50;
                             Dacamine; Decamine; Debroussaillant 600;
                             Ded-Weed; Ded-Weed LV-69; Desormone; Dicopur;
                             Dicotox; Dinoxol; DMA-4; Dormone; Duphar
                             2,4-D; Emulsamine BK; Emulsamine E-3; Envert
                             DT; Envert 171; Esteron 99; Esteron 76 BE;
                             Esteron 99 concentrate; Esterone Four;
                             Esteron 44 Weed Killer; Estone; Fernesta;
                             Fernimine; Fernimine 2,4-D; Fernimine 2,4-D;
                             Fernoxone; Ferxone; Foredex 75; Formula 40;
                             Hedonal; 2,4-D Aminesalt; Herbatox D 500;
                             Herbidal; Ipaner; Krotiline; Lawn-Keep
                             Liro-2,4-D; Liro-2,4-D Estemine 500
                             EC; Lironox; Luxan 2,4-D; acrondray; Mega-D;
                             Monosan; Moxone; Netagrone; Netagrone 600;
                             NSC 423; Pennamine; Pennamine D; Phenox;
                             Pielik; Planotox; Plantgard; Shell 2,4-D
                             Amine; Spritz-Hormin/ 2,4-D; Spritz-Hormit/
                             2,4-D; Superormone concentr; Super D
                             Weedone; Transamine; Tributon; Tussilex-2,4-D
                             80%; Tussilex-2,4-D; Twex 2,4-D; U 46
                             D-Fluid-2,4-D; U 46 D-Fluid-2,4-D; U 46 DP;
                             U-5043; Vergemaster; Verton D; Verton 2 D;
                             Vertron 2 D; Vidon 638; Visko-Rhap Low Drift
                             Herbicide; Visko-Rhap Low Volatile 4L;
                             Weed-AG-Bar; Weedar; Weedar-64; Weedasept;
                             Weed-B-Gon; Weedez Wonder Bar; Weedone Aero
                             Concentrate; Weedone LV4; Weed-Rhap;
                             Weed-Tox; Weedtrol (This list is not
                             exhaustive)

                 

    a  Formulations containing 2,4-D (alkali salts, amine salts, esters)
       as the sole active ingredient.

    Common synonyms:         2,4-D acid;
                             2,4-dichlorophenoxyacetic acid

    CAS registry number:     94-75-7 (the acid)

    1.2  Physical and Chemical Properties

    Some physical and chemical properties of 2,4-D are given in the Sample
    International Safety Card.

    1.3  Composition

    The purity of technical 2,4-D may range from less than 90% to 99%.
    Typical impurities (trace - 1.5%) include 2,6-dichlorophenoxyacetic
    acid, monochlorophenoxyacetic acid, bis (2,4-dichlorophenoxy)acetic
    acid, phenoxyacetic acid, dichlorophenols, 2,4,6-trichlorophenol,
    other chlorophenols, and water. Trace levels of chlorinated
    dibenzo- p-dioxins, varying with the production process, have been
    found in amine and ester formulations. 2,3,7,8-TCDD has not been
    found. Trace levels of  N-nitrosamines can occur in amine
    formulations, especially when nitrate is added as a corrosion
    inhibitor for containers.

    Sodium or amine salts of 2,4-D are formulated as water-soluble
    concentrates by the manufacturer. Esters of 2,4-D are formulated with
    emulsifiers and must be mixed with water for spraying. Some salt
    formulations of 2,4-D are sold as wettable powders or as granules or
    pellets using clay, sand, or some other carrier.

    2,4-D is often used in formulations containing one or more other
    active ingredients, such as 2-methoxy-3,6-dichlorobenzoic acid
    (dicamba), 2-methyl-4-chlorophenoxyacetic acid (MCPA),
    2-(2-methyl-4-chlorophenoxy)propionic acids (mecoprop, MCPP),
    2-(2,4-dichlorophenoxy)propionic acid (dichloroprop, 2,4-DP), and
    fertilizers. These formulations are sold under a wide variety of trade
    names.

    1.4  Uses

    Alkali or amine salts or esters of 2,4-D are used as herbicides
    against broad-leaf weeds in cereal crops, as well as on pastures and
    lawns, at rates of about 0.2-2.0 kg active ingredient (acid
    equivalent)/ha. Esters are also used at rates of up to 6 kg (acid
    equivalent)/ha to suppress weeds, brush, and some trees. Granular
    formulations are used as aquatic herbicides at rates of 1-122 kg/ha.
    At very low foliar application rates (20-40 mg 2,4-D/litre spray
    water), 2,4-D can be used as a growth regulator.

    2.  SUMMARY AND EVALUATION

    2.1  Exposure to 2,4-D

    In areas of 2,4-D herbicide production, handling, or use, the highest
    exposure will be incurred by workers who are directly involved in
    these processes, followed by bystanders exposed to 2,4-D vapour, dust,
    or droplets, or to contaminated vegetation, soil, or water. In these 2
    groups, most of the exposure will usually be via the skin.

    The general population will be exposed mainly through food containing
    2,4-D residues but also through 2,4-D residues in water. The
    contribution from air is negligible. As far as the general population
    in areas where 2,4-D is not used is concerned, 2,4-D intake from any
    source is negligible.

    Most 2,4-D residues result from the production and use of 2,4-D
    herbicides. Other possible minor sources of 2,4-D include the use of
    2,4-dichlorophenoxy-butyric acid (2,4-DB).

    The drifting of vapour of the more volatile esters of 2,4-D may result
    in air pollution and crop damage; these products are being replaced by
    less volatile 2,4-D derivatives.

    The use of 2,4-D for aquatic weed control may lead to contamination of
    sources of irrigation and drinking-water. Environmental pollution may
    also arise from inadequate disposal practices. Various amounts of
    2,4-D applied to a target area may be distributed in the general
    environment, within a few hours or days, by the movement of air,
    water, or soil.

    2,4-D and its derivatives are fairly rapidly broken down by chemical
    and biological processes. Persistence or accumulation of 2,4-D
    residues from normal use is occasionally possible, mainly under dry or
    cold conditions where there is little biological activity.

    Available data indicate that residues of 2,4-D rarely exceed 1 mg/kg
    in soil, several g/litre in water, several g/m3 in air, and a few
    tens of g/kg in food sources. Exceptions may occur in the vicinity of
    2,4-D herbicide spills, in water treated with 2,4-D herbicides, in
    berries and mushrooms grown in treated areas, or when excessive
    amounts of the herbicide are used.

    No information is available on the corresponding exposure levels for
    the contaminants present in 2,4-D herbicides.

    2.2  Uptake, Metabolism, and Excretion

    2,4-D and its derivatives can be absorbed via the oral, dermal, and
    inhalation routes.

    Distribution of 2,4-D occurs throughout the body, but there is no
    evidence that it is accumulated. The compound is only slightly
    transformed in mammals. A single dose is excreted within a few days,
    mainly with the urine. Little is known about the uptake and fate of
    the contaminants of 2,4-D, other than 2,4-dichlorophenol.

    In 2 acute oral studies on rats, the LD50 (lethal dose for half the
    number of exposed animals) was 375 and 666 mg/kg body weight,
    respectively, i.e., 2,4-D is moderately toxic according to the
    classification of Hodge & Sterner.

    2.3  Effects on Animals

    Death may result in mammals and birds receiving single oral doses of
    2,4-D exceeding approximately 100-300 mg/kg body weight. The most
    characteristic signs of severe 2,4-D poisoning are those of muscular
    spasms (myotonia), but various other effects have been described.

    The no-observed-adverse-effect levels for a single dose of 2,4-D and
    for some of the chronic effects of 2,4-D in animals have not been
    clearly established.

    No adequately documented reports of accidental 2,4-D poisoning of
    mammals or birds have been found.

    The no-observed-adverse-effect level for the production of
    malformations in the fetus and other adverse effects in the embryo or
    fetus appears to be about 10 mg/kg body weight per day. Available
    information is inadequate for an assessment of the genetic activity of
    2,4-D in mammals. However, the evidence suggests that 2,4-D
    derivatives are not potent mutagens.

    The carcinogenic potential of 2,4-D cannot be assessed on the basis of
    the available animal bioassays.

    2.4  Effects on Human Beings

    Single oral doses of 5 and 30 mg/kg body weight did not cause any
    acute toxic effects in human volunteers. The lethal single oral dose
    for man is uncertain. Accidental and intentional poisonings with 2,4-D
    indicate that the effects at toxic levels of 2,4-D are the same in
    human beings as in other mammals. It is uncertain whether the chronic
    toxic effects of 2,4-D products reported in occupationally exposed
    people are solely attributable to 2,4-D. Scientifically valid studies
    have not shown any adverse effects on reproduction in human beings,
    accidentally or occupationally exposed to 2,4-D.

    The results of studies on whether occupational exposure to 2,4-D may
    result in chromosome abnormalities are conflicting. The results of
    some epidemiological studies have suggested an association between
    exposure to phenoxy herbicides, including 2,4-D, and increased
    incidences of malignant tumours and tumour mortality. It is not clear,
    at present, whether this represents a true association, and if so,
    whether it is specifically related to 2,4-D.

    2.5  Estimated Intake of 2,4-D

    General population

    In an area where 2,4-D is used, the total contribution from air, food,
    and water is estimated to be 0.3-2 g/kg body weight per day. In other
    areas, the 2,4-D intake from any source is negligible.

    Bystanders

    An adequate estimate of intake is not possible at this time, but it
    should generally be less than that for occupationally-exposed persons.

    Workers

    Workers handling or using 2,4-D may absorb an average of about 0.1 mg
    2,4-D/kg body weight per day. However, this level may be exceeded if
    good occupational hygiene is not practiced. Simple precautions against
    excessive exposure can reduce the amount of 2,4-D uptake.

    3.  CONCLUSIONS

    From the data available at present, it can be concluded that there is
    no health risk for the general population from the recommended use of
    2,4-D. When appropriate safety measures are taken, there is also no
    health risk for workers.

    From: Environmental Health Criteria 29: 2,4-Dichlorophenoxyacetic Acid
    (2,4-D)

    4.  HEALTH HAZARDS FOR MAN, PREVENTION AND PROTECTION, EMERGENCY
        ACTION

    4.1  Main Hazards for Man, Prevention and Protection, First Aid

    2,4-D poisoning can result from the accidental or intentional
    ingestion of 2,4-D. When safe handling is poor, pronounced dermal
    absorption and inhalation may also lead to signs and symptoms of
    overexposure and poisoning.

    GOLDEN RULES

     1. Do not smoke, drink, or eat in the work-place.

     2. In case of overexposure, the victim should leave, or be removed
     from, the contaminated area to fresh air as rapidly as possible.

     3. Remove contaminated clothing and shoes and wash with plenty of
     water and soap.

     4. Flush affected eye(s) with water for at least 15 minutes.

    4.1.1  Prevention and protection, first aid

    The human hazards associated with certain types of exposure to 2,4-D,
    together with preventive and protective measures and first aid
    recommendations are listed in the following table.

    4.2 Advice to Physicians

    In cases of exceptional overexposure, and in cases of attempted
    suicide with 2,4-D, acute poisoning may occur. Hypersalivation,
    stomach cramps, vomiting, and diarrhoea may result. Convulsions,
    cerebral depression, and mental confusion with difficulty in speaking
    have been reported. A short period of myotonia followed by muscular
    weakness, reduced motor activity, ataxia, and incoordination may be
    followed by the disappearance of reflexes. The blood pressure may be
    low, the pulse rapid, and ventricular fibrillation has been reported.
    Liver and kidney damage may occur, as well as lung oedema. In severe
    cases, coma may develop, followed by death.

    There is no specific antidote, and symptomatic treatment should be
    given, including general supportive measures such as artificial
    respiration, when needed.

    After oral ingestion, gastric lavage (even if patient has already
    vomited) is advised if there are no signs of impending convulsions.

    Control convulsions with diazepam. Epinephrine and ephedrine should be
    avoided, because of possible ventricular fibrillation. Monitor the
    ECG.

    Forced alkaline diuresis may be helpful in increasing the rate of
    excretion of 2,4-D in life-threatening cases. This should be done with
    full laboratory control including measurements of urine pH,
    blood-electrolytes and pH, and concentrations of 2,4-D in the blood.

    If myotonia appears, quinidine may be helpful.

    4.3  Health Surveillance Advice

    Human beings who work regularly with 2,4-D should undergo periodic
    medical examination with emphasis on the neurological status, muscular
    and cardiovascular system, liver and kidney functioning, and effects
    on skin and eyes. Supervisors and workers should be alert to symptoms
    of toxic exposure and know how to give first aid.

    4.4  Safe Handling Advice

    Most problems related to handling can be avoided by observing simple
    procedures, such as:

    (a)  following the instructions on the label, which should be in the
         local language(s);

    (b)  applying the proper formulation at the proper rate;

    (c)  proper cleaning of protective clothing;

    (d)  using proper and clean spraying equipment that does not leak;

    (e)  spraying during favourable weather conditions;

    (f)  keeping bystanders away during and after spraying;

    (g)  taking extreme care in the disposal of empty containers and
         unused 2,4-D, and never storing 2,4-D formulations in containers
         normally used for food or drinking purposes; and

    (h)  proper timing of treatment for maximal weed control and minimal
         crop damage.


        ROUTE             HEALTH HAZARDS                             PREVENTION AND PROTECTION              FIRST AID
                                                                                                                                                

    SKIN              Non-irritant, but other ingredients        Wear neoprene gloves and               Remove contaminated clothing and
                      in the formulation may cause               cotton overalls                        wash it; wash contaminated
                      irritation; in cases of gross                                                     skin with water and soap
                      over-exposure, dermal absorption
                      may lead to systemic poisoning
                      (see ingestion)
                                                                                                                                                

    EYES              Non-irritant, but dust and                 Avoid contact with eyes; wear          Flush contaminated eyes with
                      solvents in formulations may               safety goggles                         plenty of water for 15 minutes;
                      irritate                                                                          if irritation persists, seek
                                                                                                        medical attention
                                                                                                                                                

    INHALATION        Vapour inhalation is unlikely;             Avoid inhalation of dust or            Fresh air
                      inhalation of dust or droplets             mist, if necessary by use of
                      may cause irritation of the                appropriate dust mask or
                      respiratory tract                          respirator
                                                                                                                                                

    INGESTION         Unlikely to occur under occupational       Do not eat, drink, or smoke
                      conditions                                 during work; wash hands

                      Deliberate ingestion (attempted                                                   Treat symptomatically, rinse
                      suicide) may lead to poisoning,                                                   mouth, give plenty of water to
                      hypersalivation, stomach cramps,                                                  drink; if breathing has stopped,
                      vomiting, and diarrhoea may                                                       apply artificial respiration; seek
                      result; convulsions, cerebral                                                     medical attention
                      depression, and mental confusion
                      with difficulty in speaking have
                      been reported; a short period of
                      myotonia followed by muscular
                                                                                                                                                

    ROUTE             HEALTH HAZARDS                             PREVENTION AND PROTECTION              FIRST AID
                                                                                                                                                

    INGESTION         weakness, reduced motor activity,
    (cont'd).         ataxia, and incoordination may be
                      followed by disappearance of
                      reflexes; the blood pressure may
                      be low, the pulse rapid, and
                      ventricular fibrillation has been
                      reported; liver and kidney
                      damage may occur as well as lung
                      oedema; in severe cases, coma
                      may develop, followed by death
                                                                                                                                                

    
    For more information on the safe handling of pesticides, see:

    (a)  ILO (1977)  Safe use of pesticides, Geneva, International Labour
         Office (Occupational Safety and Health Series No. 38).

    (b)  ILO (1979)  Guide for health and hygiene in agricultural work,
         Geneva, International Labour Office, pp. 309.

    (c)  Plestina, R. (1984)  Prevention, diagnosis, and treatment of
          insecticide poisoning, Geneva, World Health Organization
         (Unpublished report No. VBC/84.889).

    (d)  GIFAP (1983) Guidelines for the safe and effective use of
         pesticides, Brussels, GIFAP.

    4.5  Explosion and Fire Hazards

    2,4-D is not explosive or flammable. However, it should be kept away
    from sources of heat as it decomposes on heating with the formation of
    harmful gases such as hydrogen chloride, which forms mists of
    hydrochloric acid with moisture, and phosgene.

    4.6  Storage

    Store out of reach of children inside locked rooms, in well-labelled
    containers, and away from food, drink, and animal feeding stuff. Do
    not store in containers normally used for the storage of food or
    drinking purposes.

    4.7  Transport

    No special measures are indicated. Avoid contamination of food and
    feed.

    4.8  Spillage and Disposal

    4.8.1  Spillage

    Collect spillage in a container or dust bin bag. In case of liquid
    spillage, first use absorbent material. Clean up with water.

    4.8.2  Disposal (based on the IRPTC waste disposal file)

    Incineration at high temperatures (1000C) with sufficient residence
    time to lead to complete destruction is the most acceptable method for
    the disposal of 2,4-D, as far as the environment is concerned.

    Incineration at low temperatures could lead to the formation of
    chlorinated dibenzo- p-dioxins. The non-persistence and
    detoxification of 2,4-D in soil indicate that burial in noncrop areas,
    away from water supplies, would be an acceptable method for the
    disposal of small quantities of 2,4-D. Discharge in surface water and
    sewers should be avoided.

    For the decontamination of 2,4-D drums, flush the drums 3 times using
    the normal diluent at a volume equal to approximately 10% of the
    drum's capacity. Add the rinsing liquid to the spray mixture or use
    the recommended disposal methods. Small containers can be disposed of
    by hole-punching, crushing, and burial in a landfill.

    5.  INTERNATIONAL CHEMICAL SAFETY CARD

     This card should be easily available to all health workers concerned
     with, and users of, 2,4-D. It should be displayed at, or near,
     entrances to areas where there is potential exposure to 2,4-D, 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.


        2,4-DICHLOROPHENOXYACETIC ACID (2,4-D)
    (C12C6H3OCH2COOH)
                                                                                                                                                

    PHYSICAL PROPERTIES                                                                  OTHER CHARACTERISTICS
                                                                                                                                                

    Relative molecular mass                         221.0                                Colourless, white to yellow powder; the
    Melting point (C)                              140-141                              compound decomposes on heating with
    Solubility in water                             slightly soluble                     formation of harmful gases; the
    Solubility in organic solvents                  soluble                              compound can be absorbed into the
    Relative vapour density                         7.6                                  body by inhalation and ingestion and
    Vapour pressure (160C)                         52.3 Pa                              via the skin
    pKa (25C)                                      2.64-3.31
                                                                                                                                                

    HAZARDS/SYMPTOMS                           PREVENTION AND PROTECTION                 FIRST AID
                                                                                                                                                

    SKIN: Irritation, redness;                 Minimize exposure, wear                   Remove and wash contaminated
    absorption via the skin can be             neoprene gloves, cotton                   clothing; wash skin with plenty of water
    significant and may lead to poisoning      overalls                                  and soap

    EYES: Irritation, redness                  Minimize exposure, wear                   Flush eyes with plenty of water
                                               safety goggles

    INHALATION: Inhalation of                  Minimize exposure, apply                  Fresh air
    dust and droplets may cause                local exhaust ventilation;
    irritation                                 protect breathing by a 
                                               suitable respirator or dust mask

    INGESTION: Unlikely in occupational        Do not eat, drink, or smoke
    situation                                  during work; wash hands
                                                                                                                                                

    HAZARDS/SYMPTOMS                           PREVENTION AND PROTECTION                 FIRST AID
                                                                                                                                                

    INGESTION (accidental or                   Treat symptomatically, obtain medical
    deliberate): May lead to                   attention immediately
    poisoning, with confusion and
    difficulty in speaking
                                                                                                                                                

    SPILLAGE                                   STORAGE                                   FIRE
                                                                                                                                                

    Collect spillage in container or           Store cool and dry in                     Not flammable, but liquid formulations
    dust bin bag; in case of liquid            original packaging and                    may be flammable; the substance
    spillage, first use absorbent              away' from food and feed;                 decomposes on heating: hydrochloric
    material; clean up with water              empty containers should                   acid, phosgene, and chlorinated dioxins
                                               be punctured                              may be formed
                                                                                                                                                

    WASTE DISPOSAL
                                                                                                                                                

    Waste should be incinerated at             National Occupational                     UN: 2766, 2999, 3000
    high temperatures (1000C);                Exposure Limit:
    burial of small quantities of 2,4-D
    in noncrop areas away from water           National Poison Control
    supplies may be acceptable; avoid          Centre:
    discharge in to surface water and
    sewers; comply with local
    regulations

    FIGURE 2
                                                                                                                                                
    
    6.  HAZARDS FOR THE ENVIRONMENT AND THEIR PREVENTION

    Exposure of non-target crops, livestock, and wildlife may occur by
    drift and volatilization from sprayed fields and/or by improper
    spraying methods. Toxic effects on aquatic animals could result from
    the use of ester formulations of 2,4-D as aquatic herbicides.

    Avoid unintentional contamination of sensitive crops, livestock and
    wildlife, and surface waters by using less volatile ester formulations
    of 2,4-D in sprays. Ester formulations of 2,4-D should not be used as
    aquatic herbicides; the amine salt formulations are less toxic for
    aquatic animals. Avoid contamination of soil, water, and atmosphere by
    proper methods of storage, transport, handling, application, and waste
    disposal. In case of spillage, use the methods advised in section 4.8.

    7.  CURRENT REGULATIONS, GUIDELINES, AND STANDARDS

    The information given in this paragraph has been extracted from the
    International Register of Potentially Toxic Chemicals (IRPTC) legal
    file.

    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. A full reference to the
    original national document from which the information was extracted
    can be obtained from the IRPTC.a

    When no effective date appears in the IRPTC legal file, the year of
    the reference from which the data are taken is shown, indicated by
    (r).

    7.1  Exposure Limit Values

    See following table.

    7.2  Specific Restrictions

    In the United Kingdom, 2,4-D is approved as a systemic herbicide, and
    specified uses, limitations, and safety precautions are listed. The
    herbicide is also approved for use in or near water, unless applied
    within 3 weeks from the start of irrigation, and is approved for
    application by ULV equipment (1983 (r)). In Sweden, aerial spraying of
    certain preparations comprising 2,4-D is permitted against certain
    pests (1984 (r)). In the Federal Republic of Germany, the handling of
    2,4-D is prohibited or restricted for adolescents and pregnant or
    nursing women (effective date: 1980).

    7.3  Labelling, Packaging, and Transport

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

    FIGURE 3

                 

    a  International Register of Potentially Toxic Chemicals, Palais des
       Nations, 1211 Geneva 10, Switzerland (Telephone No. 988400-985850).

    The label must read: harmful by inhalation, in contact with skin, and
    if swallowed; keep away from food, drink, and animal feeding stuffs -
    keep out of reach of children.

    The European Community legislation on labelling of pesticide
    preparations classifies 2,4-D in Class  IId for the purpose of
    determining the label for preparations containing 2,4-D and other
    active ingredients (1976 (r)).

    The United Nations Committee of Experts on the Transport of Dangerous
    Goods classifies 2,4-D as a poisonous substance (Class 6.1) with minor
    danger for packing purposes (Packing Group III). Packaging methods and
    a label are recommended (1982 (r)). The recommended label is:

    FIGURE 4

    7.4  Waste Disposal

    In the USA, any solid waste (from manufacturing facilities),
    containing this substance, must be listed as hazardous waste (subject
    to handling, transport, treatment, storage, and disposal regulation
    and permit and notification requirements), unless it is found that the
    waste cannot pose a threat to human health or the environment when
    improperly managed (effective date: 1980). An owner or operator of a
    hazardous waste incinerator must achieve 99.99% destruction and
    removal efficiency for this substance if it is designated as a
    principal organic hazardous constituent in its EPA permit (effective
    date: 1981). An owner or operator of certain specified types of
    hazardous waste, storage, treatment, or disposal facilities must
    install a groundwater monitoring system and periodically report on the
    concentrations of the substance (effective date: 1980). Facilities
    disposing of commercial (non-domestic) solid waste must not
    contaminate an underground drinking-water source by causing the
    concentration of 2,4-D in groundwater to exceed 0.1 mg/litre, or by
    causing any increase if that level is already exceeded (effective
    date: 1979).

    Permits are required for the discharge of 2,4-D from any point-source
    into USA waters (1981 (r)).

    7.5  Other Measures

    The European Community legislation on the discharge of dangerous
    substances into the aquatic environment prohibits the discharge of
    2,4-dichlorophenoxyacetic acid into groundwater. For other waters, it
    requires that national authorities give specific discharge
    authorizations with discharge conditions (total quantity and
    concentration).


        SOME EXPOSURE LIMIT VALUES
                                                                                                                                                

    Medium      Specification          Country/               Exposure limit descriptiona,b                   Value              Effective
                                       organization                                                                              date
                                                                                                                                                

    AIR         Occupational           Argentina              Maximum permissible concentration (MPC)                            1979
                                                              -- TWA                                          10 mg/m3
                                                              -- STEL                                         20 mg/m3

                                       Australia              Threshold limit value (TLV)                                        1983 (r)
                                                              -- TWA                                          10 mg/m3

                                       Belgium                Threshold limit value (TLV)                     10 mg/m3

                                       Finland                Maximum permissible concentration (MPC)                            1982 (r)
                                                              -- TWA                                          10 mg/m3

                                       Germany, Federal       Maximum work-site concentration (MAK)                              1985 (r)
                                       Republic of            -- 8-h TWA                                      10 mg/m3
                                                              -- STEL (30 min,                                50 mg/m3
                                                              2  per shift) (average value)

                                       Hungary                Maximum allowable concentration (MAC)                              1978 (r)
                                                              -- TWA                                          1 mg/m3
                                                              -- STEL (30 min)                                2 mg/m3

                                       Netherlands            Maximum allowable concentration (MAC)                              1985 (r)
                                                              -- TWA                                          10 mg/m3

                                       Romania                Maximum permissible concentration (MPC)                            1975 (r)
                                                              -- TWA                                          5 mg/m3
                                                              -- Ceiling value                                10 mg/m3
                                                                                                                                                

    SOME EXPOSURE LIMIT VALUES (cont'd).
                                                                                                                                                

    Medium      Specification          Country/               Exposure limit descriptiona,b                   Value              Effective
                                       organization                                                                              date
                                                                                                                                                

                                       Switzerland            Maximum work-site concentration (MAK)                              1984 (r)
                                                              -- TWA                                          10 mg/m3

                                       United                 Recommended limit                                                  1985 (r)
                                       Kingdom                -- TWA                                          10 mg/m3
                                                              -- STEL                                         20 mg/m3

                                       USA (OSHA)             Permissible exposure limit (PEL)                                   1974
                                                              -- TWA                                          10 mg/m3

                                       USSR                   Maximum allowable concentration (MAC)                              1977
                                                              -- Ceiling value for aerosols                   1 mg/m3

                                       Yugoslavia             Maximum allowable concentration (MAC)                              1971 (r)
                                                              -- TWA                                          10 mg/m3

    WATER       Drinking-, Bottled     USA                    Maximum permissible concentration (MPC)         0.1 mg/litre       1981 (r)

                Drinking-              WHO                    Guideline level                                 0.1 mg/litre       1983 (r)

                Ambient                Mexico                 Maximum permissible concentration (MPC)         0.01 mg/litre      1973
                (coastal waters)

                Ambient (estuaries)    Mexico                 Maximum permissible concentration (MPC)         0.1 mg/litre       1973

    FOOD                               Brazil                 Acceptable levels -- in specified plant                            1984 (r)
                                                              products (security interval: 30 days)           0.05-2 mg/kg
                                                                                                                                                

    SOME EXPOSURE LIMIT VALUES (cont'd).
                                                                                                                                                

    Medium      Specification          Country/               Exposure limit descriptiona,b                   Value              Effective
                                       organization                                                                              date
                                                                                                                                                

                                       FAG/WHO                Acceptable daily intake (ADI)                   0.3 mg/kg          1981 (r)
                                                              body weight

                                       FAG/WHO                Maximum residue limit (MRL)                                        1978 (r)
                                                              -- in specified plant products                  0.05-5 mg/kg       1981 (r)

                                       Germany, Federal       Maximum residue limit (MRL)                                        1984
                                       Republic of            -- in specified plant products                  2 mg/kg
                                                              -- generally, in other plant products           0.1 mg/kg

                                       Kenya                  Maximum limit                                                      1978 (r)
                                                              -- in specified food products                   0.2 mg/kg

                                       Sweden                 Maximum tolerable concentration (MTC)                              1985
                                                              -- in specified plant products                  0.1-2 mg/kg

                                       USA                    Acceptable residue limits (ARE)                                    1982 (r)
                                                              -- in specified plant products                  0.05-5 mg/kg

                                       USA                    Acceptable residues limit (ARE)                                    1981 (r)
                                                              -- In raw agriculture:
                                                              -- in specified plant products                  0.1-1000 mg/kg
                                                              -- in specified animal products                 0.05-2 mg/kg
                                                              -- in specified fish products                   1 mg/kg
                                                                                                                                 1981 (r)
                                                                                                                                                

    SOME EXPOSURE LIMIT VALUES (cont'd).
                                                                                                                                                

    Medium      Specification          Country/               Exposure limit descriptiona,b                   Value              Effective
                                       organization                                                                              date
                                                                                                                                                

                                       USA                    Residue tolerance
                                                              -- in specified food products                   2-5 mg/kg

                                       USSR                   Acceptable daily intake (ADI)                                      1983
                                                              (prohibited in all food products)               0.001 mg/kg

    SOIL                               USSR                   Maximum allowable concentration (MAC)           0.1 mg/kg          1984
                                                                                                                                                

    a  TWA = time-weighted average over one working day (usually 8 h).    b  STEL = short-term exposure limit.
        


    See Also:
       Toxicological Abbreviations