Reaction mass of Sodium, bis[3-[(4,5-dihydro-3-methyl-5-oxo-1-phenyl-1H-pyrazol-4-yl)azo]-2-hydroxy-5-nitrobenzenesulphonato(3-)]chromate(1-) and sodium [3-[(4,5-dihydro-3-methyl-5-oxo-1-phenyl-1Hpyrazol-4-yl)azo]-2-hydroxy-5-nitrobenzenesulphonato(3-)]hydroxychromate(1-)]

Endpoint summary

Description of key information

Short-term toxicity to aquatic invertebrates

EC50 (48 h) = 24.1 mg/l

Toxicity to aquatic plants other than algae

ECr50 based on frond numbers = 13.8 mg/l (nominal) and 12.3 mg/l (measured).

ECr50 based on dry weight = 11.4 mg/l (nominal) and 10.1 mg/l (measured).

Additional information

Justification for classification or non-classification

According to the CLP Regulation (EC n. 1272/2008), Part 4: Environmental Hazards, the substances can be classified for hazardous to the aquatic environment (fish toxicity) when the following criteria are met:

A )Acute (short-term) aquatic hazard

Category Acute 1:

96 hr LC 50 (for fish) ≤ 1 mg/l and/or

48 hr EC 50 (for crustacea) ≤ 1 mg/l and/or

72 or 96 hr ErC 50 (for algae or other aquatic plants) ≤ 1 mg/l

B) Long-term aquatic hazard

(iii) Substances for which adequate chronic toxicity data are not available

Category Chronic 1:

96 hr LC 50 (for fish); 48 hr EC 50 (for crustacea); 72 or 96 hr ErC 50 (for algae or other aquatic plants) ≤ 1 mg/l

and the substance is not rapidly degradable and/or the experimentally determined BCF ≥ 500 (or, if absent, the log K ow ≥ 4).

Category Chronic 2:

96 hr LC 50 (for fish); 48 hr EC 50 (for crustacea); 72 or 96 hr ErC 50 (for algae or other aquatic plants) > 1 mg/l ≤10 mg/l

and the substance is not rapidly degradable and/or the experimentally determined BCF ≥ 500 (or, if absent, the log K ow ≥ 4).

Category Chronic 3:

96 hr LC 50 (for fish); 48 hr EC 50 (for crustacea); 72 or 96 hr ErC 50 (for algae or other aquatic plants) > 10 to ≤ 100 mg/l

and the substance is not rapidly degradable and/or the experimentally determined BCF ≥ 500 (or, if absent, the log Kow ≥ 4).

Category Chronic 4

Cases when data do not allow classification under the above criteria but there are nevertheless some grounds for concern. This includes, for example, poorly soluble substances for which no acute toxicity is recorded at levels up to the water solubility (note 4), and which are not rapidly degradable in accordance with section 4.1.2.9.5 and have an experimentally determined BCF ≥ 500 (or, if absent, a log K ow ≥ 4), indicating a potential to bioaccumulate, which will be classified in this category unless other scientific evidence exists showing classification to be unnecessary. Such evidence includes chronic toxicity NOECs > water solubility or > 1 mg/l, or other evidence of rapid degradation in the environment than the ones provided by any of the methods listed in section 4.1.2.9.5.

The LC50 value calculated for the test substance on the "short-term toxicity to fish" was established to be 35 mg/l, therefore the substance, for this test, is classified asCategory Chronic 3(96 hr LC 50 (for fish) > 10 to ≤ 100 mg/l).

The LC50 value calculated for the test substance on the "long-term toxicity to aquatic invertebrates" was established to be > 15 mg/l, with a LOEC value of 5 mg/l.

Based on the above results the Lemna study provides the lowest value that will be used for Classification (Chronic 3).