INTOX Home Page



                          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 personnel on the 
                    diagnosis and treatment of cases of poisoning and on 
                    laboratory tests. 

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

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

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.

       The values quoted are based on published information and unpublished 
information from reliable sources.  Since brevity is desirable and a 
considerable mount 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
Class                   Oral                            Dermal
                Solids        Liquids            Solids        Liquids
Ia extremely    < 5           < 20              < 10          < 40

Ib highly      5 - 50        20 - 200            10 - 100        40 - 400

II moderately  50 - 500     200 - 2000          100 - 1000       400 - 4000

III slightly    > 500       > 2000              > 1000         > 4000

3.2    Notes on the parts of the data sheets


1.1.2         Synomyms

       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. 

1.2    Synopsis

       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 on toxicity and hazard will be found at the end of the 
explanatory notes. 

1.3.2         Solubility

       The following are technical equivalents of the phrases used:

       highly soluble > 80%

       soluble 40% to 80%

       moderately soluble 5% to 40%

       slightly soluble 10 ppm to 5%

       practically insoluble < 10 ppm

1.3.3         Stability

       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. 

1.3.4         Vapour pressure

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

1.4    Agriculture, horticulture and forestry

1.4.1         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. 

1.4.4         Unintended effects

       This heading includes known effects on the environment.


2.1    Toxicology - mammals

2.1.4         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 many 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. 

2.1.7         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 

2.1.8         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, have been noted.  Such 
alterations in toxicity may enhance or diminish the inherent toxicity of 
the pesticide. 

2.2    Toxicology - man

2.2.5         Reported mishaps

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

2.3    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 LC50 
- 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 are as 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. 

3.1    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 "concerns" 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. 

3.3    Handling

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

3.5    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 

3.7    Labelling

       The wording of a label is important but the type of information 
required varies considerably from country to country.  Therfore, 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. 

4.1.2         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 sheets are those of the American 
Conference of Government Industrial Hygienists (ACGIH and those published 
by the USSR, if available). 

4.3    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.                      

4.4    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. 

5.2    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

5.3.1         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. 

                                 = = =