1-Naphthalenesulfonic acid, 4-amino-, diazotized, coupled with diazotized 5(or 8)-amino-2-naphthalenesulfonic acid, diazotized 4-nitrobenzenamine and resorcinol

Endpoint summary

Description of key information

Short-term toxicity to aquatic invertebrates:

EC₅₀ (Daphnia magna, 48 h) > 100 mg/L (nominal)

Toxicity to aquatic plants other than algae:

E_rC₅₀ (Lemna minor, 7d) = 100 -1000 mg/L (nominal)

Additional information

The following data was obtained for Similar Substance 01 and Similar Substance 03 on Daphnia magna and Lemna minor, respectively. It is expected that the Target Substance will present similar effect levels to these aquatic organisms. Justification for the use of a read-across approach is provided in Section 13 of IUCLID.

Invertebrate acute toxicity

The acute toxicity of Similar Substance 01 to Daphnia magna under static conditions was investigated in an experimental study, according to the OECD Guideline 202 screening test (2004). Groups of 40 Daphnia magna (20 per tank) were exposed to test item concentrations of 1 mg/L (low-concentration group), 10 mg/L (mid-concentration group) and 100 mg/L (high concentration group) for a duration of 48 hours. Daphnia were monitored for immobility at 24 and 48 hours. A negative control group of 60 Daphnia (20 per tank) were tested in parallel.

No immobilisation was observed in control or treatment tanks after 24 hours. After 48 hours, the three control groups experienced 5 %, 10 % and 5 % immobilisation; 5 % and 10 % immobilisation occurred in groups exposed to 1 mg/L and 10 mg/L; 20 % immobilisation occurred in the groups exposed to 100 mg/L. No analytical measurement of test item concentration was performed throughout the test. Based on immobilisation, the 48-hour EC₅₀ value was found to be greater than 100 mg/L based on nominal concentrations.

Aquatic Plants toxicity

The inhibitory effects of the test item toLemna minorwere investigated over a period of 7 days, according to the OECD Guideline 221 (2006). The test was performed at concentrations of 10, 100 and 1000 mg/l of organic content(corresponding to 16.7, 167 and 1670 mg/l of test item). The determination of the effect concentrations was based on the nominal concentrations, assuming that the test item is stable in water for the whole test period.

Based on the data observed with respect to growth rate and yield for the frond number endpoint, the E_rC₅₀and the E_yC₅₀were found to be 100-1000 mg/l and approximately 100 mg/l based on organic content, respectively. The no-observed-effect concentrations toLemna minorwith respect to growth rate (NOE_rC) and yield (NOE_yC) for the endpoint frond numbers were 10 mg/l organic content, as determined by Dunnett's test.

 

JUSTIFICATION FOR CLASSIFICATION OR NON-CLASSIFICATION

According to the CLP Regulation (EC) No. 1272/2008, Part 4: Environmental Hazards, substances can be classified as hazardous to the aquatic environment when the following criteria are met:

A) Acute (short-term) aquatic hazard Category Acute 1: 96-hour LC₅₀ (fish) and/or 48-hour EC₅₀ (crustacea) and/or 72- or 96-hour E_rC₅₀ (algae or other aquatic plants) ≤ 1 mg/l.

B) Long-term aquatic hazard (iii) Substances for which adequate chronic toxicity data are not available and the substance is not rapidly degradable and/or the experimentally determined BCF ≥ 500 (or, if absent, the log K ow ≥ 4).

- Category Chronic 1: 96-hour LC₅₀ (fish) and/or 48-hour EC₅₀ (crustacea) and/or 72- or 96-hour E_rC₅₀ (algae or other aquatic plants) ≤ 1 mg/l;

- Category Chronic 2: 96-hour LC₅₀ (fish) and/or 48-hour EC₅₀ (crustacea) and/or 72- or 96-hour E_rC₅₀ (algae or other aquatic plants)> 1 to ≤10 mg/l;

- Category Chronic 3: 96-hour LC₅₀ (fish) and/or 48-hour EC₅₀ (crustacea) and/or 72- or 96-hour E_rC₅₀ (algae or other aquatic plants) > 10 to ≤ 100 mg/l.

 

The substance is not rapidly degradable and the available tests on acute toxicity to invertebrates and aquatic plants fixed effect levels which do not meet the criteria for the hazard categories for acute and chronic aquatic toxicity. Therefore, the substance is not classified for aquatic toxicity according to the CLP Regulation (EC) No. 1272/2008.