Benzoic acid, 2-hydroxy-, reaction products with formaldehyde, coupled with diazotized 5-amino-8-[[4-[(4-nitro-2-sulfophenyl)amino]phenyl]azo]-2-naphthalenesulfonic acid disodium salt

Endpoint summary

Description of key information

Short-term toxicity to aquatic invertebrates:

EC₅₀ (Daphnia magna, 48 h) ≥ 100 mg/L (nominal, verified by measured conc.)

Toxicity to aquatic plants other than algae:

E_rC₅₀ (Lemna minor, 7d) ≥ 100 mg/L (nominal, verified by measured conc.)

Microorganisms:

IC 50 (3 h) > 1000 mg/L

Additional information

Invertebrate short-term toxicity

A static test was performed according to the OECD Guideline 202 (2004) and the EU method C.2 of the Regulation (EC) No. 440/2008. 5 concentrations were used ranging from 4.6 to 100 mg/L (nominal concentration). For each test concentration and the blank control, 20 Daphnia were exposed to the test item for 48 hours. After 24 and 48 hours, the immobilised Daphnia were counted.

The measured concentrations lay between 89 % and 97 % of the nominal concentrations at the beginning of the test and between 97 % and 107 % of the nominal concentrations at the end of the test.

Therefore, the determination of the biological results was based on the nominal concentration.

Aquatic Plants toxicity

A static test was performed according to the OECD Guideline 202 (2004) and the EU method C.2 of the Regulation (EC) No. 440/2008. 5 concentrations were used ranging from 4.6 to 100 mg/L (nominal concentration). For each test concentration and the blank control, 20 Daphnia were exposed to the test item for 48 hours. After 24 and 48 hours, the immobilised Daphnia were counted.

The measured concentrations lay between 89 % and 97 % of the nominal concentrations at the beginning of the test and between 97 % and 107 % of the nominal concentrations at the end of the test.

Therefore, the determination of the biological results was based on the nominal concentration.

Additional tests

The substance was tested in an activated sludge respiration inhibition test following a method similar to the OECD 209 method. During the range finding study the substance was tested at four nominal concentration from 1 to 1000 mg/L during a contact time of three hours. The request for the definitive study was to carry out a limit test during a contact time of three hours at the no observed effect level and not to determine an EC50. Thus, for the definitive test the concentration tested was 1 mg/L and the inhibition was about 5 %. The EC50 (3 h) for the Reference Substance was found to be 11 mg/L. Percentages of inhibition observed at the reference substance concentrations were comparable for range finding study and for definitive study. From this data, it can be evinced that the sensitivity of sludge used should be considered to be normal in both studies.

The EC50 can only be stated as being as being > 1 mg/L from the definitive study, as it was not possible to give a higher value from the results of the definitive study alone. However, from the range finding study the EC50 for the test material exceeded 1000 mg/L.

In addition, a summary of short-term toxicity results on different substances, including the substance, is available. The substances were tested for acute toxicity to Oncorhynchus mykiss at nominal concentrations of 100, 200, 300, 400 ppm wt/vol during a study period of 48 h. The LC50 (48 h,Oncorhynchus mykiss) of the sustance was graphically determined to be 135 ppm wt/vol.

 

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.