Carbazamidine monohydrochloride

Endpoint summary

Description of key information

Short-term toxicity to aquatic invertebrates

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

Toxicity to aquatic algae

EC50 (72 h, Desmodesmus subspicatus)= 10 mg/l (nominal)

Additional information

The following data was obtained for Similar Substance 01 on Daphnia magna and Desmodesmus subspicatus. 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.

Short-term toxicity to aquatic invertebrates

In order to test acute toxicity to invertebrates, Daphnia magna was exposed to five nominal concentrations of the test item (25, 35, 50, 71 and 100 mg/L) and blank control solution for a period of 48 hours under static conditions. Mobility and visible abnormalities were recorded at 24 and 48 hours.

Based on immobilisation, the 48-hour EC50 value was found to be greater than 100 mg/L based on nominal concentrations.

Toxicity to aquatic algae

In order to test acute toxicity algae, Desmodusmus suspicatus was exposed to the test solution of seven nominal concentrations of test item (0.78, 1.56, 3.13, 6.25, 12.5, 25 and 50 mg/L) and a blank control solution for a period of 72 hours under static conditions. The cell densities were measured at 24 hours interval. Inhibition of the algal population was measured as reduction in growth rate (index r) relative to control cultures grown under identical conditions.

After 72 hours of exposure an ErC10 of 2.9 mg/L and an ErC50 of 10.0 mg/L were determined.

JUSTIFICATION FOR 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 ErC50 (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 ErC50 (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 ErC50 (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 ErC50 (algae or other aquatic plants) > 10 to ≤ 100 mg/l.

The substance is not rapidly degradable and the available test on acute toxicity to aquatic alae fixed effect levels which meet the criteria for the hazard category chronic 2. Therefore, the substance is classified H411: Toxic to aquatic life with long lasting effects according to the CLP Regulation (EC) No. 1272/2008.