# Regulation (EC) No 1272/2008 of the European Parliament and of the Council of 16 December 2008 on classification, labelling and packaging of substances and mixtures, amending and repealing Directives 67/548/EEC and 1999/45/EC, and amending Regulation (EC) No 1907/2006 (Text with EEA relevance), Division 4.1.2.3

Extent: E+W+S+N.I.

The criteria for classification of a substance in Acute 1 are defined on the basis of acute aquatic toxicity data only (EC50 or LC 50). The criteria for classification of a substance into Chronic 1 to 3 follow a tiered approach where the first step is to see if available information on chronic toxicity merits long-term (chronic) hazard classification. In absence of adequate chronic toxicity data, the subsequent step is to combine two types of information, i.e. acute aquatic toxicity data and environmental fate data (degradability and bioaccumulation data) (see Figure 4.1.1).
Figure 4.1.1
Categories for substances long-term (chronic) hazardous to the aquatic environment

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Source: https://www.legislation.gov.uk/eur/2008/1272/annex/I/division/4/division/4.1/division/4.1.2/division/4.1.2.3 (the official version)
Page: https://openlegislation.uk/eu-regulation-2008-1272/annex-I/division-4/division-4.1/division-4.1.2/division-4.1.2.3
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.