Disodium 4,4'-bis(5-hydroxy-3-methyl-1-phenyl-1H-pyrazol-4-ylazo)-1,1'-biphenyl-2,6'-disulphonate

Endpoint summary

Description of key information

Short-term aquatic toxicity to aquatic invertebrates

EC50 (48h) > 39.4 mg/l ( >100 mg/l nominal)

Toxicity to aquatic plants other than algae

ErC50 = 256 mg/l

Additional information

Short-term aquatic toxicity to aquatic invertebrates

The acute toxicity of the test substance to the water flea Daphnia magna STRAUS was investigated in a 48-hour static test according to EEC Directive 92/32/EEC (December 1992). The test substance was tested in the range of concentrations between 12.5 mg/l and 100 mg/l. The dilution factor was 2.

lnstead of mortality the test criterion of the acute toxicity is immobilization of the daphnids after 48 hours of exposure which is expressed as EC (effect concentration). Those animals were considered to be immobile which were unable to swim within 15 seconds even after gentle agitation of the test vessel.

EC50 (48h) > 39.4 mg/l ( >100 mg/l nominal)

Toxicity to aquatic plants other than algae

There are no experimental available data of the target substance, thus the information on the Similar Substance 02 have been taken into account. T

The test was conducted according to the OECD 221 end the results were summarized below:

Growth rate inhibition (ErC50) and yield inhibition (EyC50) for the endpoint frond numbers was estimated to be 256 – 2560 mg/l nominal concentration.

Growth rate (NOErC) and yield (NOEyC) for the endpoint frond numbers were 25.6 mg/l nominal concentration, as determined by Dunnett's test.

 

Growth rate inhibition (ErC50)for the endpoint dry weight was estimated to be 256 – 2560 mg/l nominal concentration

Yield inhibition (EyC50) was estimated to be 25.6 – 256 mg/l nominal concentration.

Growth rate (NOErC) and yield (NOEyC) for the endpoint dry weight were < 25.6 mg/l nominal concentration, as determined by Dunnett's test.

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) ≤ 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

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) > 1 to ≤10 mg/l and/or

48 hr EC 50 (for crustacea) > 1 to ≤10 mg/l and/or

72 or 96 hr ErC 50 (for algae or other aquatic plants) > 1 to ≤10 mg/l (Note 2)

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) > 10 to ≤ 100 mg/l and/or

48 hr EC 50 (for crustacea) > 10 to ≤ 100 mg/l and/or

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 K ow ≥ 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 EC50 value, calculated in toxicity test on Daphnia magna,was greather than 39.4 mg/l measured concentration and > 100 mg/l nominal concentration. Based on the nominal concentration, it is possible to conclude that the test substance is not classified for this test.

This result is in line with the one obtained in the toxicity test to aquatic plants and the one performed on algae, carried out on Similar Substance 01 and similar substance 2, where the ErC50 was established to be 256 mg/l and >100 mg/l respectively.

In conclusion the substance is Not Classified, according to the CLP Regulation (EC n. 1272/2008).