ISO 257:2004

INTERNATIONAL ISO
STANDARD 257
Third edition
2004-06-15

Pesticides and other agrochemicals —
Principles for the selection of common
names
Produits phytosanitaires et assimilés — Principes pour le choix des
noms communs




Reference number
ISO 257:2004(E)
©
ISO 2004

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ISO 257:2004(E)
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ISO 257:2004(E)
Contents Page
Foreword. iv
Introduction . v
1 Scope. 1
2 Normative references . 1
3 Terms and definitions. 1
4 Purpose of common names. 1
5 Principles for selection. 2
5.1 General. 2
5.2 Salts and esters. 2
5.3 Purity of chemicals . 4
5.4 Isomers and isomeric mixtures . 4
5.5 Additional requirements. 5
5.6 Recommended stems . 6
6 Style of writing or printing common names.6
Annex A (informative) Procedure for the establishment of common names for pesticides and
other agrochemicals . 8
Annex B (informative) System for constructing common names for isomers and isomer mixtures
of pyrethroids and related compounds .15
Bibliography . 17

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ISO 257:2004(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 257 was prepared by Technical Committee ISO/TC 81, Common names for pesticides and other
agrochemicals.
This third edition cancels and replaces the second edition (ISO 257:1988), which has been technically revised.
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ISO 257:2004(E)
Introduction
This International Standard contains principles for the construction of common names for pesticides and other
agrochemicals. The intention is to create short, distinctive, easily pronounced names, which will be common to
all languages, as far as is possible. This International Standard contains recommended names for common
ions and radicals, as well as recommended stems for different chemical structures. Therefore the common
name should reflect any relationship with chemicals of a similar structure. However, it is important to avoid
confusion between common names and existing names, whether they are other common names, trade names
or chemical names. Recommendations on how to name isomers, salts, esters, etc. are also included.
These principles are defined for the guidance of proposers of such common names and for the operation of
ISO/TC 81.

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INTERNATIONAL STANDARD ISO 257:2004(E)

Pesticides and other agrochemicals — Principles for the
selection of common names
1 Scope
This International Standard gives principles for creating common names for pesticides and other
agrochemicals. These principles are defined for the guidance of proposers of such common names.
The procedure for the establishment of common names is given in Annex A.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 1750, Pesticides and other agrochemicals — Common names
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
common name
name freely available for common use in identifying a chemical substance without recourse to its systematic
chemical name
4 Purpose of common names
4.1 The purpose of a common name (see ISO 1750) is to provide a short, distinctive, easily pronounced
name for a substance, the full chemical name of which is too complex for convenient use in science,
commerce and official regulations.
4.2 Because a common name has to be freely available for use in describing the substance for which it has
been coined, it should not be permitted to become a privately owned trade mark with respect to identical or
similar goods.
4.3 In order to achieve the desired goal of creating a common name that is generally acceptable
internationally, rejection of any proposed common name by individual ISO Member Bodies [see A.3.1.3 and
A.4.1.1 e)] should only be based on serious grounds and then only after every possible effort has been made
to overcome the impediment to local acceptability.
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ISO 257:2004(E)
5 Principles for selection
5.1 General
5.1.1 No substance should be given a common name if its chemical name is reasonably short and
distinctive (e.g. metaldehyde, carbon tetrachloride).
5.1.2 The identity of a common name should be maintained in all languages, subject to necessary linguistic
variations.
5.1.3 Common names should be as short as is practicable, but should not include single letters and/or
numerals except as structural qualifiers.
NOTE While the formation of common names from initials and numerals is no longer acceptable, exceptions (e.g.
MCPA, 2,4,5-T) have been made for substances which are so well known by such names that to use other names would
cause confusion.
5.1.4 Common names should be distinctive in sound and spelling and should be neither difficult to
pronounce nor liable to confusion with existing names (see 5.5.1).
5.1.5 To facilitate international spelling and translation, “f” instead of “ph” should be used in common
names; the suffix “-phenyl” in the names of esters, however, should retain its normal spelling. Similarly “t”
should be used instead of “th” with the permitted exceptions “thrin” and “thiuron”. Methyl and ethyl esters
retain their normal spelling.
5.2 Salts and esters
5.2.1 Simple salts
The common name for a simple salt should be that of the parent acid, alcohol or base. In the case of an acid
or alcohol, the complementary cation may be given as a hyphenated suffix and, in the case of a base, the
complementary anion may be stated. A quaternary ammonium or phosphonium salt should be treated as a
salt of a base.
EXAMPLES:
 alloxydim-sodium,
 bromoxynil-potassium,
 imazalil nitrate,
 chlormequat chloride.
5.2.2 Simple esters
Similarly, where the substance is a simple ester or other derivative, and the existence of biological activity
derives from the parent form, the common name should be that of the parent. This should be taken as the
case if other esters or derivatives are known, or are expected, to exhibit similar biological activity.
The complementary esterifying radical may be indicated.
EXAMPLES:
 mecoprop-methyl,
 dinoseb acetate.
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ISO 257:2004(E)
5.2.3 Complex esters and salts
If neither moiety of an ester or salt is simple, the common name should be that of the whole molecule.
EXAMPLES:
 bupirimate,
 decafentin.
5.2.4 Recommended names for ions and radicals
Recommended names have been developed for some of the more commonly occurring ions and radicals.
These are listed in Table 1 and should be used in place of the chemical names.
Table 1 — Names for ions and radicals
Recommended name Chemical name
albesilate
alkylbenzenesulfonate
butometyl 2-butoxy-1-methylethyl
butotyl
2-butoxyethyl
diclexine dicyclohexylammonium
dimolamine
(2-hydroxyethyl)dimethylammonium
diolamine bis(2-hydroxyethyl)ammonium
ethadyl ethylene (ethane-1,2-diyl)
etotyl 2-ethoxyethyl
isoctyl “iso-octyl” (mixed C-8 alkyl radical)
meptyl 1-methylheptyl
metilsulfate methylsulfate
mexyl 1-methylhexyl
olamine 2-hydroxyethylammonium
tefuryl tetrahydrofurfuryl
trimesium trimethylsulfonium
trolamine tris(2-hydroxyethyl)ammonium

Traditional names for radicals, as retained in Reference [2], should be used in place of systematic or semi-
systematic names that include locants.
EXAMPLES:
 butyrate,
 dimethylammonium,
 fumarate,
 isobutyl,
 isopropyl,
 isopropylammonium,
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ISO 257:2004(E)
 methylammonium,
 triethylammonium.
5.2.5 Multiplying affixes
Multiplying affixes should be used when the parent is a dibasic (or higher) acid, alcohol or base and more than
one possible derivative could be produced. Affixes should also be used in any other case where there is a
need to avoid ambiguity.
EXAMPLES:
 chlorthal-dimethyl,
 chlorthal-monomethyl,
 diquat dibromide,
 iminoctadine triacetate,
 streptomycin sesquisulfate,
 thiosultap-disodium.
It is not normally necessary to use multiplying affixes with the parent substance.
EXAMPLES:
 dalapon-magnesium [2:1 ratio],
 fosetyl-aluminium [3:1 ratio],
 oxpoconazole fumarate [2:1 ratio].
5.3 Purity of chemicals
Although common names should be given to chemical entities of known structure, in exceptional cases they
may be given to mixtures whose composition is constant for all practical purposes and whose concentrations
of active components can be specified.
Such exceptional cases may include:
a) a reaction product mixture, provided that the concentrations of the main active components fall within
acceptable limits about specified proportions;
b) a polymeric reaction product mixture, provided that the concentrations of the main active component
polymers (the repeating units of which are specified) in the reaction product mixture are known and are
constant to within acceptable limits;
c) an extract or derivative of a natural product (from animal, plant, fungal or bacterial sources), the
composition of which is constant within acceptable limits.
5.4 Isomers and isomeric mixtures
5.4.1 The following special considerations should be taken into account when coining names for mixtures of
isomers.
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ISO 257:2004(E)
5.4.2 The common name for a substance that can exist in enantiomeric (optically isomeric) forms owing to a
single asymmetric centre should be assigned, without affixes, either to the racemate or to one of the
enantiomers, depending on the form for which the common name is first required. If a common name is
required subsequently for another stereochemical variant, it should be the original common name with the
appended suffix “-MP”, “-M” or “-P”, for the racemate, the (−) isomer or the (+) isomer, respectively.
If more than one chiral centre is present, it may be necessary to adopt special measures, such as a system
based on appropriate modification of the original common name, for example that developed for the synthetic
pyrethroids (see Annex B).
5.4.3 The common name of a substance which consists of complementary geometrical isomers should
indicate the essential familial features (see 5.6). A specific isomer or subgroup of isomers of such a substance
may be assigned a common name [which may include a syllable or letter(s) implying a cis-, trans-, (E)- or (Z)-
form] only if the substance is produced commercially in a substantially pure form.
If a normal commercial product consists of a mixture of a single pair of isomers, the common name should
apply to any mixture of the two. Individual isomers should be identified by suitable qualifiers, for example cis
and trans or (E) and (Z).
If it is commercially possible to produce mixtures with different ratios of isomers, the ratio should be stated on
the commercial product, for example “60:40”. The ratios will not form part of the common name.
5.4.4 The common name for a substance that consists of a mixture of optical and geometric isomers should
be one that is appropriate to the mixture and may be modified by qualifiers, to specify subgroups or individual
isomers.
5.4.5 If a substance consists of a mixture of structural isomers, only one of which has the stated biological
activity, the common name should be assigned only to the active isomer. However, if the substance consists
of a mixture of pesticidally active isomers, and if the isomerism consists of variations in chain branching or
position of substituents, the common name should be assigned to the mixture, which should be defined as an
isomeric reaction product mixture of A + B. In ISO 1750, footnotes giving indications of the usual proportions
are included. If necessary, names for individual isomers may be derived by modifying the common name
applied to the mixture.
5.5 Additional requirements
5.5.1 A common name should not be liable to confusion with
a) established chemical names,
b) common names already either officially authorized or in well-recognized use for other pharmaceutical,
pesticidal or related substances, or
c) trade marks enjoying legal protection with respect to pharmaceutical, pesticidal or related substances,
unless the prior consent of the trade mark owner has been secured in writing.
5.5.2 In accordance with its definition and purpose (Clauses 3 and 4), a common name cannot be a
proprietary name with respect to goods broadly of the same category. However, in some cases,
circumstances may exist during an interim period which make it desirable for proprietary rights to be
maintained as, for example, where the proposer has agreed to surrender his proprietary rights subject to
acceptance of the name as an official common name. In such cases, the proprietor should first agree in writing
to discontinue the use of the name as a trade mark as soon as official recognition as a common name is given
by ISO, and thus
a) to permit the use of the name as the approved common name by any party whatsoever who is properly
using it, and
b) to surrender all proprietary rights as soon as the special circumstances justifying their retention have
ceased to exist.
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ISO 257:2004(E)
5.5.3 A common name should not be included in a national standard until it is considered that conflicts with
legally protected trade marks are unlikely and that the name is likely to be internationally acceptable.
5.5.4 If a common name is proposed for a substance which is closely related both chemically and in
biological properties to an already named compound, it is preferred but not required that the proposal should
reflect the similarity by using a common root (which may or may not be a recommended stem; see 5.6) in
conjunction with syllables suggestive of the variation.
EXAMPLES:
 ethirimol dimethirimol
 chlorotoluron chloreturon
 carbofuran decarbofuran
 formetanate formparanate
 permethrin cypermethrin
5.6 Recommended stems
5.6.1 A common name should, if appropriate, include a stem indicative of the types of compound listed in
Table 2.
The recommended stem should be used in the name at the position specified. Judicious use of other non-
chemical rather than chemical stems in a common name provides greater flexibility and reduces the possibility
of conflict with existing names.
It is emphasized that there is no intention of applying this recommendation retrospectively.
5.6.2 Other stems have previously been recommended for use in common names (see Table 3). These
stems, whilst obsolescent, should still be restricted to use in names for the type of compound indicated.
5.6.3 The use of stems with misleading chemical significance should be avoided. For example, a name
ending in “-ol” or “-one” is not acceptable for a compound that is not an alcohol (or phenol) or a ketone
respectively.
6 Style of writing or printing common names
Common names should be treated as common nouns and should not, therefore, be capitalized except where
required by national usage. Some common names, which were coined before these principles were
elaborated, consist of initials and/or numerals. If such names consist only of initials, they should be written in
capitals without intervening full-stops (e.g. MCPA). If numerals and letters both occur, the numerals should be
separated from one another by commas and from letters by a hyphen (e.g. 2,4,5-T).
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ISO 257:2004(E)
a
Table 2 — Recommended stems
Position
Stem Type of compound Example
in name
-alin suffix 2,6-Dinitroanilines trifluralin
-azine suffix 1,3,5-Triazines, chloro-substituted atrazine
-azon suffix Cyclic acylhydrazides chloridazon
-azone suffix N-acyl or N-phenyl triazolones sulfentrazone
carb- or any position Carbamates and thiocarbamates carbofuran
-carb- or -carb
-conazole suffix Fungicides and plant growth regulators based on imidazole or penconazole
1,2,4-triazole and containing a halogenated phenyl group
coum- or -coum prefix or suffix Coumarins coumatetralyl
-fop suffix 2-(4-Aryloxyphenoxy)propionic acids fluazifop
-fop- infix 2-(4-Aryloxyphenoxy)propionic acid derivatives other than trifopsime
salts and esters
fos- or any position Organophosphorus compounds quintiofos
-fos- or -fos
imaz- prefix Imidazolinone (HRAC group B) imazapyr
-lure suffix Pheromone attractants or synthetic analogues thereof —
-mectin suffix Analogues of avermectin abamectin
-meton suffix 1,3,5-Triazines, methoxy-substituted secbumeton
-oxydim suffix Alkyl 2-hydroxy-6-oxocyclohexenyl ketone oximes cloproxydim
-ozide suffix 1,2-Diacyl-1-alkylhydrazine insect growth regulators tebufenozide
-prole suffix N-Arylpyrazoles vaniliprole
-quat suffix Quaternary nitrogen compounds paraquat
-strobin suffix Analogues of strobilurin azoxystrobin
-sulam suffix Aminosulfonyltriazolopyrimidines diclosulam
-sulfuron suffix Sulfonylureas bensulfuron
-thiuron suffix Thioureas chloromethiuron
-thrin suffix Esters of cyclopropanecarboxylic acids (pyrethroids) permethrin
b
-tryn suffix 1,3,5-Triazines, methylthio-substituted simetryn
-uron suffix Acyclic ureas and ureas in which one or both nitrogen atoms linuron
form part of a saturated ring system
a
The recommendations are based on the chemical structures of the compounds.
b
In English, the ending “-tryne” was originally recommended, but was abandoned because the ending might be thought to indicate
the presence of a C≡C grouping (see 5.6.3).

Table 3 — Obsolescent stems
Stem Position in name Type of compound Example
din- prefix Dinitrophenols dinoterb
-eb suffix Ethylenebisdithiocarbamates maneb
-nil suffix Nitriles chlorothalonil
-rim suffix Pyrimidines fenoxacrim

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ISO 257:2004(E)
Annex A
(informative)

Procedure for the establishment of common names for pesticides and
other agrochemicals
A.1 Glossary of English terms and definitions
A.1.1
proposed common name
name submitted by the sponsor
NOTE 1 Information supplied by the sponsor is regarded as confidential at this stage.
NOTE 2 The French term is “proposition de nom commun”.
A.1.2
draft proposal for a common name
name circulated for preliminary enquiry to ISO/TC 81
NOTE 1 Names at this stage should not be used in the literature or for any other purpose. The information that is
circulated is considered to be in the public domain, and no longer confidential.
NOTE 2 The French term is “avant-projet de nom commun”.
A.1.3
provisionally approved common name
name approved by ISO/TC 81 for inclusion in a list for letter ballot by ISO member bodies
NOTE 1 Names that have reached this stage are often used in the literature, on product labels, and for registration and
other purposes. It is possible, but very unusual, for a name to be changed or rejected after reaching this stage.
NOTE 2 The French term is “nom commun provisoirement approuvé”.
A.1.4
approved common name
name that has successfully passed the ISO voting stage, but has not yet been published in ISO 1750 or one
of its addenda or amendments
NOTE 1 Names that have reached this stage will not be changed before publication, and may be used without
qualification in the literature, on product labels, and for registration and all other purposes.
NOTE 2 The French term is “nom commun approuvé”.
A.1.5
published common name
name that has been published in ISO 1750 or one of its addenda or amendments
NOTE The French term is “nom commun publié”.
A.1.6
national common name
name that has been published in a national standard of a particular country
NOTE 1 The country should be stated.
NOTE 2 The French term is “nom commun national”.
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ISO 257:2004(E)
A.2 Stage 1: Proposed common name
A.2.1 Submission
A.2.1.1 Proposed common names are submitted to the ISO/TC 81 Secretariat, normally through the
national standards body of the country concerned, for consideration with a view to adoption by ISO.
Submissions by other routes (e.g. from the manufacturers direct to the Secretariat or by the distributors in a
country other than that in which the substance is manufactured or originates) are permissible.
A.2.1.2 Proposed common names submitted for letter ballot to the USA National Committee, or conveyed
to the Secretariat by any other national committee, are assumed to have been submitted to the Secretariat for
consideration and adoption by ISO/TC 81 without a specific request to this effect being necessary, unless a
definite statement is made by the sponsor that the sponsor does not wish the name to be considered by ISO.
NOTE As a matter of principle, such statements are deprecated, because adoption of common names, which are
used throughout the world, on a purely national level, without knowledge of their international acceptability, is certain to
give rise to problems. The main such problem is the potential use of different common names in different geographical
contexts, which defeats the object of standardization.
A.2.2 Information required
The following information is required to accompany a proposal for a new common name:
a) the proposed common name, alternatives being allowed;
b) the systematic chemical name (see Note 1) for the compound to which the common name is to be
applied, including
1) stereochemical identifiers, in the case of compounds that exist in different stereochemical forms, and,
if appropriate, the proportions of the various isomers,
2) in the case of compounds of uncertain composition, as much information on the chemical constitution
as possible, and
3) the Chemical Abstracts Service Registry Number or Numbers, as appropriate.
c) the molecular formula;
d) the structure of the compound or compounds (see Note 2) to which the common name is to be applied,
indicating the stereochemistry if appropriate [see A.2.2 b)];
e) where the substance is a simple ester or other derivative, an indication as to whether the existence of
biological activity derives from the parent form; this is to be taken as the case if other esters or derivatives
are known, or are expected, to exhibit similar biological activity;
f) the name and address of the sponsor, together with any proprietary names, including trade marks, for the
product;
g) any other trivial names, code numbers or abbreviations for the compound;
h) the use of the product (see Note 3).
NOTE 1 Three systematic chemical names will be included in ISO 1750, namely those corresponding to
 the English interpretation of the IUPAC rules,
 the French interpretation of the UICPA rules, and
 the rules used by Chemical Abstracts.
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ISO 257:2004(E)
These three names are provided by the recognized authorities in the United Kingdom and Canada and by the Chemical
Abstracts Service.
NOTE 2 The structures will, if necessary, be redrawn to ensure self-consistency within ISO 1750.
NOTE 3 At present, the uses for which abbreviations (in parentheses) have been established by ISO/TC 81 are as
follows:
acaricides (A) molluscicides (M)
algicides (AL) nematicides (N)
attractants (AT) plant growth regulators (P)
bactericides (B) plant activators (PA)
disruptants (D) rodenticides (R)
fungicides (F) repellants (RE)
herbicides (H) safeners (S)
insecticides (I) avicides (V)
insect growth regulators (IGR) synergists (Y)

A.2.3 Secretariat examination
A.2.3.1 The Secretariat examines all proposed common names. Unless there are strong reasons not to
do so, the proposals proceed to the next stage (preliminary enquiry), after a careful check on the information
supplied (see Note 1 in A.2.2) and redrawing of the structure (see Note 2 in A.2.2). The sponsors are informed
of the action taken.
A.2.3.2 The Secretariat examination at this stage is on “absolute grounds”, by which is meant compliance
with the principles set out in this International Standard. The most common reasons for a proposed common
name not being acceptable at this stage are as follows:
a) misleading chemical significance, for example a name ending in “-ol” if the compound is not an alcohol or
phenol;
b) the compound concerned being a salt or
...