Cuprate(2-), [mu-[[3,3'-[methylenebis[(4,6-dihydroxy-3,1-phenylene)azo]]bis[4-hydroxy-5-nitrobenzenesulfonato]](6-)]], sodium potassium

Endpoint summary

Description of key information

Short-term aquatic toxicity to invertebrates

EC50 (48h) = 6.8 mg/l

Toxicity to aquatic plants other than algae

ErC50 = 10.6 mg/l (effects on dry weight)

NOErC < 3.36 mg/l (effects on dry weight)

Additional information

The following tests are available on the similar substance 1:

Short-term aquatic toxicity to invertebrates

The test substance was tested in acute immobilisation test on Daphnia magna, according to method C.2 – Daphnia sp. Acute Immobilisation Test, Council Regulation (EC) No. 440/2008.

The preliminary test was performed in a range of the test substance nominal concentrations 1 – 100 mg·L^-1.Based on toxicity of the test substance found in the preliminary test, the definitive test was performed in appropriate concentration range. The definitive test was performed static, in a range of the test substance nominal concentrations 1 – 50 mg·L^-1.

The study was performed without analytical determination of the test substance concentrations. Only the concentrations of Total organic carbon (TOC) in the lowest and in the highest tested concentration were analysed in the preliminary and definitive test.Samples for determination of the TOC concentrations were taken at the beginning and at the endof the test.The nominal concentrations were used for all evaluation and results.

The EC50 calculated in this test in a 48 hours observation window is 6.8 mg/l.

 

Toxicity to aquatic plants other than algae

The inhibitory effects of the test substance to the duckweed Lemna minor were investigated over a period of 7 days, based on the frond number and biomass (dry weight), following the guideline OECD 221.

The test solutions were prepared by respective dilutions of a stock solutionin STEINBERG Medium.

The test was performed at 100, 50.0, 25.0, 12.5 and 6.25 mg/l nominal concentration of the test substance, corresponding to 61.9, 31.0, 15.5, 7.74 and 3.87 mg/l of the active ingredient.

Three parallel test vessels were used for each test concentration of the test item and six vessels for the blank controls.

The test concentrations during the 7-day test period were determined by photometry at the beginning of the test, as well as after 3, 5 and 7 days of exposure. These analyses confirmed the right dosage of the test item, and showed that the concentrations of the test item slightly decreased over the whole 7-day test period. Therefore, the effective concentrations (E_rC_xand E_yC_x) were assessed based on the geometric mean (GM) of the measured concentrations of the active ingredient.

The two endpoints frond number and biomass (dry weight) were investigated at days 3, 5 and 7, and each of them were assessed as growth rate and yield.

The ErC50 value, based on frond number and dry weight, was respectively 17.5 and 10.6 mg/l. The NOErC was 3.36 mg/l based on frond number and < 3.36 mg/l based on dry weight.

 

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 for the test substance on the "short-term aquatic toxicity to invertebrates" (Daphnia) was established to be 6.8 mg/l, therefore the substance is classified as Category Chronic 2 (48 hr EC 50 (for crustacea) > 1 to ≤10 mg/l) according to the CLP Regulation (EC n. 1272/2008).