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The issue of this document does not constitute formal publication. It should not be reviewed, abstracted or quoted without the agreement of the World Health Organization. Authors alone are responsible for views expressed in signed articles.

Ce document ne constitue pas une publication. Il ne doit faire l'objet d'aucun compte rendu ou résumé ni d'aucune citation sans l'autorisation de l'Organisation Mondiale de la Santé. Les opinions exprimées dans les articles signés n'engagent que leurs auteurs.

Introduction to data sheets


Data sheets on pesticides have been introduced to provide basic information on individual compounds, and arising out of this information, recommendations on their use and control are given. Details of symptoms of poisoning and emergency and medical treatment are also provided.

It is hoped that these data sheets will promote the safe and effective use of pesticides, both for the preservation of the health of people directly exposed and for the protection of people more remotely affected through changes in the environment resulting from injudicious application. Although each country adopts control measures suited to its economy and culture, it is also hoped that the recommendations in the data sheets may lead to a degree of international standardization in the control of pesticides.

Throughout these notes, the word "pesticide", unless otherwise stated includes both the technical product and its formulations.

It must be noted that the issue of a data sheet for a particular pesticide does not imply endorsement of the pesticide by WHO or FAO for any particular use; or exclude its use for other purposes not stated. While the information provided is believed to be accurate according to data available at the time when the sheet was compiled, neither WHO nor FAO are responsible for any errors or omissions, or any consequences therefrom.


Each sheet is presented in five parts for each pesticide. The headings of the parts are as follows:

Part 1 -

General information

Part 2 -

Toxicology and risks

Part 3 -

Recommendations for regulatory authorities on the regulation of the pesticide

Part 4 -

Prevention of poisoning in man and emergency aid

Part 5 -

Information for medical and laboratory

Certain parts may be re-issued as new information is incorporated into them.

The values quoted are based on published information and unpublished information from reliable sources. Since brevity is desirable and a considerable amount of sometimes conflicting information exists for some pesticides, an element of selection occurs in the compilation of the data. In order to ensure that the sheets present a balanced view, each is reviewed by a panel of consultants before issue.


3.1 Toxicity and hazard

The toxicity of a pesticide is measured according to a number of indices (such as oral and dermal LD50) based on tests carried out on laboratory animals. Although this provides a valuable indication of the likely hazard to man, it is not identical with this hazard.

Hazard depends on the various routes by which men may absorb a pesticide and this to some extent depends on the physical state of the pesticide being used, and the method of use (or type of misuse).

The table below shows a classification according to hazard using oral and dermal toxicity indices. It is presented as a guide only and it is emphasized that other factors can also influence hazard in the use of a particular pesticide.


LD50 rat mg/kg







Ia extremely hazardous





1b highly hazardous





II moderately hazardous


200-2 000

100-1 000

400-4 000

III slightly hazardous


>2 000

>1 000

>4 000

3.2 Notes on the parts of the data sheets





Since the name of a pesticide as marketed may vary between manufacturers and from country to country, trade names have not normally been included under this heading. Local names for the pesticide may be usefully inserted by the reader on the data sheet in the space provided.




This is a general statement on the nature of the pesticide. The toxicity of a pesticide is graded in most cases according to the LD50 value of the technical product for rats. This value is expressed throughout in milligrams of the pesticide per kilogram body weight of the test animal.


However, the toxicity of a compound does not always depend on the effects of acute single dosage on which the LD50 is based, and therefore pesticides may be placed in a category other than that based on LD50 alone, if evidence of other toxicological effects observed in long- or short-term studies are such as to justify this change. A note of toxicity and hazard will be found at the end of the explanatory notes.




The following are technical equivalents of the phrases used:


highly soluble




40% to 80%


moderately soluble

5% to 40%


slightly soluble

10 ppm to 5%


practically insoluble

<10 ppm




Where available, the degradation rate (usually the half-life) of the pesticide in water is given; otherwise, a short statement is included on the stability of the pesticide under specified conditions of pH, temperature, etc. It is not practicable to quote the stability of the pesticide in soil as this is variable depending on soil type, vegetation, climate, etc.


Vapour pressure


This has been included to give an indication of the volatility of the pesticide, and hence its relative hazard due to inhalation.


Agriculture, horticulture and forestry


Common formulations


These refer to the formulations most commonly in use. Other concentrations or mixtures of the pesticide may be formulated locally. Space has been made for the insertion of local formulations.


Unintended effects


This heading includes known effects on the environment.



Toxicology and risks


Toxicity, single dose


This gives data for experimental animals from which values for man may be inferred in the absence of any direct data relating to man. Published data on acute oral and dermal toxicity sometimes vary for a particular pesticide. The value given is the modal value, or a value which has been determined for the pesticide in the WHO scheme for the evaluation of insecticides by a WHO collaborating laboratory under carefully controlled conditions.

Most susceptible species


This refers to the least LD50 value published for any mammalian species. It has been included to give an indication of the range of toxicity between the most susceptible mammalian species and the rat, the usual animal used for toxicity testing. If the figures differ considerably, the values have to be extrapolated to man with caution.


Supplementary studies of toxicology


This refers to short-or long-term studies for carcinogenicity, teratogenicity, mutagenicity and neurotoxicity. Where a subheading does not appear on a data sheet, this means that no relevant information is available.


Modifications of toxicity


Under this section reported variations in toxicity when the pesticide is combined with other pesticides or chemicals, or variations associated with other factors such as malnutrition, has been noted. Such alterations in toxicity may enhance or diminish the inherent toxicity of the pesticide.


Toxicology - man


Reported mishaps


Under this heading, major incidents of outbreaks of poisoning, accidentally caused, have been noted.


Toxicology, other species


The entries in these sections are intended to draw attention to special risks and to give warnings of any needs for special precautions.


An indication is given of the toxicity of chemicals to fish, birds and beneficial insects. The toxicity in fish may be expressed as the LC 50 - the lethal concentration in water for 50% of the test fish during the time specified.


This sheet has been designed to give guidance to regulatory authorities; therefore only such matters as are amenable to regulation have been included and the recommendations represent the minimum standard of desirable control. More complete details of the type of protection to be provided, the type of medical surveillance to be carried out, etc., can be found in parts 4 and 5.


Recommended restrictions on availability


Recommended restrictions on availability are given under this heading. The categories set out below do not include the prohibition of the use of a very highly toxic compound. Such prohibition may be desirable if control measures cannot be enforced to the extent that safety in the use of the compound can be assured. However, this is a matter for national decision in the light of prevailing circumstances. The definitions of the categories are as follows:


Category 1 - The pesticide should be available only to applicators, individually licensed, who have demonstrated a good knowledge of the chemical, its uses and hazards, and the precautions to be taken in use.


This category applies only to a few very highly toxic pesticides.


Category 2 - Pesticide should be available only to concerns which will apply the pesticide under strictly controlled and supervised conditions, using trained operators. The application of pesticides will normally be the major part of their commercial operation.


The term "concern" includes contractors, pest control operators, etc. This category applies to most very highly toxic pesticides and other pesticides for which it is felt that special training or supervision in use is necessary.


Category 3 - Pesticides should be available to commercial applicators, for whom the application of a pesticide is not a major part of their commercial operations, subject to a permit being received from a competent authority, specifying the pesticide, conditions of use and the precautions to be taken.


The term "commercial applicators" includes farmers, orchardists, foresters, fishermen etc. and those responsible for bulk food storage. This category applies to pesticides which are highly toxic, and to pesticides which have an adverse effect on the environment to the extent that their uncontrolled use without permit is undesirable.


Category 4 - Pesticide should be available in the same manner as for category 3, without requirement that a permit be issued.


This category applies to toxic pesticides that may be distributed for commercial use but should not be available to the general public.


Category 5 - Pesticide may be made available to the general public for specified uses. This category applies to all pesticides or their formulations not included in categories 1 to 4.




This heading refers to the manipulation of the chemical after withdrawal from storage and includes application.


Selection, training and medical supervision of workers


The medical examinations described under this heading refer to pre-employment medical examinations. Subsequent medical examinations are mentioned where these are specific; otherwise usual occupational health practice should be followed. It is appreciated that in many circumstances it is difficult to provide medical examinations and supervision for agricultural workers. The practice set out in the data sheet is the ideal. However, adequate training is always necessary, and even if no regular medical supervision is possible, the possibility of training work supervisors in the prevention and signs of poisoning should not be overlooked.




The wording of a label is important but the type of information required varies considerably from country to country. Therefore, the only wording suggested is a minimum cautionary statement. Wherever possible this wording is based on that used in the WHO publication "Specifications for Pesticides" under the section "Packing and Marketing of Packages". Other details may be added as desired, based on recommendations made in other parts of the data sheet. Labels should be written in the language of the user and, in addition to the cautionary statement, should include the name of the manufacturer, the approved name of the pesticide, the type of formulation, recommended uses, the shortest possible interval from application to harvest and instructions on the disposal of the container.


This part is designed primarily for personnel in the occupational health field, and for use of supervisors. The information on emergency aid (section 4.4) has been added to this sheet as it should be part of the training of workers and others exposed to the pesticide.


Manufacture and formulation


The term "TLV" refers to the Threshold Limit Value, sometimes known as the Maximum Allowable Concentration of the pesticide in air normally permitted in industrial environments. There are many scales of TLV values. The two that are quoted on the data sheet are those of the American Conference of Government Industrial Hygienists (ACGIH) and those published by the USSR, if available.


Safe disposal of containers and spillage


The decontamination of containers refers to procedures which will normally render the container safe to be used for other purposes, except for the storage of food or drink. It has been inserted since many containers are objects of value when they have been emptied, but it does not refer to containers in which pesticides are distributed in small quantities to the general public.


Where it is stated that decontamination should not be permitted, this means that there is no safe or practicable method of decontamination using chemicals commonly available.


Emergency aid


This is known as "First Aid" in some countries.


This sheet has been designed to give basic information to medical and laboratory personnel to enable them to diagnose and treat cases of poisoning and to carry out surveillance and analytical techniques. References have been given only to standard methods and therefore, where these have stood the test of time, the references may be some years old.


Surveillance methods


The term "surveillance methods" refers to laboratory methods for determining degrees of absorption of pesticides. The term "hazard level" means the level in a particular test at which a man is showing absorption to the extent that he should cease contact with the pesticide, whether or not he demonstrates any symptoms of poisoning. This section is particularly applicable to blood cholinesterase levels resulting from poisoning by anticholinesterase pesticides.

Laboratory methods


Detection and analysis


This section gives references to methods reported in the literature. In addition to those cited in the individual data sheets, the following textbooks may prove useful.

    See Also:
       Toxicological Abbreviations