Classification of Environmental Hazards [D3]
Principles of classification
The procedures for classification and labelling of a pesticide product (a mixture) can be seen as a two-step process where the first step consists of the hazard classification and the second of the preparation of the label.
Hazard classification considers only the intrinsic properties of active ingredients or pesticide products.
It incorporates the following main activities:
- Identification of relevant data regarding the hazards of an active ingredient or pesticide product.
- Subsequent review of those data to ascertain the hazards associated with the active ingredient or pesticide product.
- A decision on whether the active ingredient or product will be classified as a hazardous substance or mixture and the degree of hazard, where appropriate, by comparison of the data with agreed hazard classification criteria.
Generally, the data required in the registration process of pesticides is globally recommended and should consequently be available also for classification of these products. The classification procedure for pesticides can therefore be more straightforward than for chemicals in general. The guidance for classification of environmental hazards in this document is assuming that the major part of the relevant data is available for the pesticide product that is being evaluated.
The GHS contains the following two environmental hazard classes:
1. Hazardous to the aquatic environment
Acute aquatic toxicity means the intrinsic property of a substance to be injurious to an organism in a short-term aquatic exposure to that substance.
Chronic aquatic toxicity means the intrinsic property of a substance to cause adverse effects to aquatic organisms during aquatic exposures which are determined in relation to the life-cycle of the organism.
The acute and the chronic classification categories are applied independently.
2. Hazardous to the ozone layer
Chemicals that are hazardous to the ozone layer are those included and regulated under the Montreal Protocol on Substances that Deplete the Ozone Layer.
The Montreal Protocol is structured around several groups of halogenated hydrocarbons that deplete stratospheric ozone. All the ozone depleting substances controlled by the Montreal Protocol contain either chlorine or bromine (substances containing only fluorine do not harm the ozone layer).
Currently the only pesticide in the Montreal Protocol is methyl bromide which is listed in Annex E.
Hazard categories
Each hazard class is differentiated in hazard categories, with the lower number representing a higher, more serious, hazard. For instance, an acute hazard Category 1 poses a more serious aquatic hazard than an acute hazard Category 3).
Hazard class | Hazard category | ||||
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← more serious | less serious → | ||||
Hazardous to the aquatic environment |
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Short-term (acute) aquatic hazard | 1 | 2 | 3 |
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Long-term (chronic) aquatic hazard |
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Adequate chronic toxicity data – non-rapidly degradable substances | 1 | 2 |
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Adequate chronic toxicity data – rapidly degradable substances | 1 | 2 | 3 |
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Substances without adequate chronic toxicity data | 1 | 2 | 3 |
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Poorly soluble substances for which no acute toxicity is recorded at levels up to the water solubility, and which are not rapidly degradable and have a log Kow ≥ 4, indicating a potential to bioaccumulate | 4 | ||||
Hazardous to the ozone layer | 1 |
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Labelling elements
Annex A1 of the GHS contains classification and labelling tables where pictograms, signal words and hazard statements can be found for all hazard classes and hazard categories. A summary table for environmental hazards is provided below:
Hazard class | Hazard category | Pictogram | Signal word | Hazard statement |
|---|---|---|---|---|
Hazardous to the aquatic environment, short-term (acute) | Acute 1 | | Warning | Very toxic to aquatic life |
Acute 2 | No pictogram | No signal word | Toxic to aquatic life | |
Acute 3 | No pictogram | No signal word | Harmful to aquatic life | |
Hazardous to the aquatic environment, long-term (chronic) | Chronic 1 | | Warning | Very toxic to aquatic life with long lasting effects |
Chronic 2 | No signal word | Toxic to aquatic life with long lasting effects | ||
Chronic 3 | No pictogram | No signal word | Harmful to aquatic life with long lasting effects | |
Chronic 4 | No pictogram | No signal word | May cause long lasting harmful effects to aquatic life | |
Hazardous to the ozone layer | 1 | | Warning | Harms public health and the environment by destroying ozone in the upper atmosphere |
Data required for environmental classification
Comprehensive data is generally required for pesticides when applications are submitted to authorities for registration. Such data is therefore provided in the submitted dossiers and can be used for classification purposes. Relevant data may also be available on-line in many countries and regions (see the Scientific Reviews or Pesticide Properties in the Information sources module in the Toolkit.
The following data generally need to be available to classify GHS environmental hazards. If data have been generated with the pesticide product, these have preference. Alternatively, toxicity data for the active ingredient, as well as relevant other components of the pesticide product, should be assessed.
Detailed information about the data required for environmental classification can be found in the “data requirement and test guidelines” module of the Toolkit, by clicking on the links in the table below, as well as in Annex 9 of the GHS.
Hazard class | Relevant studies as a basis for classification of a pesticide |
|---|---|
Hazardous to the aquatic environment | |
Degradation and potential for bioaccumulation | |
Degradation and reaction products at pH 4, 7 and 9 under sterile conditions | |
Direct photo transformation of relevant metabolites, degradation and reaction products in water with artificial light under sterile conditions | |
Degradation in aquatic systems | |
Aerobic aquatic metabolism | |
Anaerobic aquatic metabolism | |
Partition coefficient, log Kow | |
Bioconcentration factor (BCF) | |
Short term (acute) aquatic hazard1 | |
Acute toxicity crustacea | |
Fish early-life cycle or equivalent | |
Aquatic plant toxicity test (Lemna spp) | |
Long- term (chronic) aquatic hazard2 | Fish early life cycle |
Aquatic invertebrate life cycle | |
Hazardous to the ozone layer | |
No specific studies required. Listing in the Montreal Protocol indicates this hazard | |
1 These species are considered as surrogate for all aquatic organisms and data on other species such as Lemna may also be considered if the test methodology is suitable. 2 Chronic toxicity data are less available than acute data and the range of testing procedures less standardized. The NOECs or other equivalent ECx should be used. | |
Assigning hazard categories
The GHS describes in detail how hazard categories should be assigned for each environmental hazard class. A summary of these methods can be found by clicking on the entries below. More detail is provided in the GHS document.
- Hazardous to the aquatic environment
- Hazardous to the ozone layer [yet to be implemented]
Procedures for classification
The Registration Authority can use different approaches to classify the product or verify a proposed classification. Which of these approaches can be applied, depends on the exact pesticide product to be classified and on the human resources available at the Registration Authority.
These different approaches are described in more detail under Assessment methods.