Reaction product of disodium 4,4'-dinitrostilbene-2,2'-disulphonate, p-[(4-amino-2,5-xylyl)azo]benzenesulphonic acid, 3-[(4-amino-2-methoxyphenyl)azo]-4-hydroxybenzenesulphonic acid, copper (II) sulfate

Endpoint summary

Description of key information

Short-term toxicity to fish: LC50(48h) = 104 mg/l

Short-term toxicity to invertebrates: EC50 (48h) = 39.1 mg/l

Toxicity to aquatic plants other then algae: ErC50(7d)= 123 mg/l

Toxicity to microorganisms BST > 300 mg/l

Additional information

The assessment is based on information gathered by studies conducted in order to evaluate the acute toxicity to fish, invertebrates, aquatic plants and microorganisms. In all experiments the purity of samples are between 75 and 100 %.

Acute administration to fish:

The substance has been tested for acute administration of fish according to the Ciba Geigy internal method 11. The purity of sample is around the 75 %.

The test substance shows a very low toxicity to fish. The LC50 after 96 hours was determined graphically, and the result is : 140 mg/l (105 mg/l based on active ingredient).

LC50 = 105 mg/l a.i.

Acute toxicity testing on invertebrates:

The substance was tested in acute immobilisation test on Daphnia magna. The test was performed according to method C.2 – Daphnia sp. Acute Immobilisation Test, Council Regulation (EC) No. 440/2008, published in O.J.L 142, 2008.

The definitive semi-static test was performed in a range of the test substance nominal concentrations 33 – 125 mg/l.

Because concentrations of the test substance have not been satisfactorily maintained within ± 20 percent of the nominal or measured initial concentration throughout the test, time-weighted mean concentrations were used for all evaluations and results.

Test results:

EC50 (48h) = 39.1 mg/l

48 hour–EC0 = 25.2 mg/l; 48 hour–EC₁₀₀> 86.9 mg/l 

Toxicity to aquatic plants other than algae:

The inhibitory effects of test item to the duckweed Lemna minor were investigated over a period of 7 days, based on the frond number and biomass (dry weight), According to the OECD Guideline 221. The test was performed at 400, 200, 100, 50 and 25 mg/l nominal concentration.

The concentration analyses confirmed the right dosage of the test item, and showed that the concentrations of the test item decreased over the whole 7-day test period. Therefore, the effective concentrations (E_rC₅₀and E_yC₅₀) were assessed based on the geometric mean (GM) of the measured concentrations.

The two endpoints frond number and biomass (dry weight) were investigated at days 2, 5 and 7, and each of them were assessed as growth rate and yield.

E_rC₅₀(7d) = 123 mg/l

Toxicity to microorganisms

The substance has been tested for acute bacterial toxicity testing in sewage sludge according to the Ciba Geigy Internal Method n. 58. The purity of sample is around the 75 %. BST is the lowest concentration which clearly inhibits bacterial growth, based on visible opacity of the test solution. The test item shows a

BST > 300 mg/l.

Justification for classification or non-classification

As observed from these results the substance does not shows signs of toxicity from two of the three trophic levels. The values from toxicity to fish and algae are above the trigger values for classification according to the CLP Regulation (EC n. 1272/2008). The toxicity value for Daphnia magna (the most sensitive specie) are:

NOEC 48h = 25.2 mg/l

EC50 48h = 39.1 mg/l

EC100 48h > 86.9 mg/l.

The values are below the limit for avoiding the classification (10 mg/l < Category Chronic 3 ≤ 100 mg/l.

Based on values reported above the classification as Aquatic Category Chronic 3 (H412: Harmful to aquatic life with long lasting effects) is proposed according to the CLP Regulation (EC n. 1272/2008).