Registration Dossier

Ecotoxicological information

Toxicity to microorganisms

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

Available information:
The respiration rate of an activated sludge exposed to 1,1-DPE and fed with a standard amount of synthetic sewage feed was measured.. The inhibitory effect of the test substance was expressed as a percentage of the mean respiration rates of two controls. For a respiration inhibition test to be considered valid, the control values should be within 30% of each other. An EC50 obtained for the reference material must be within 2-25 mg/L. The control coefficient variation was 24% and an EC50 value of 9.19 mgIL was determined for the reference substance, rendering the test valid. For test substance 1-Phenylethylbenzene, an EC50 of> 1 000 mg/L was obtained at 3 hours post dose. Results presented are based on nominal concentrations.
The influence of Phenyl-tolyl-ethane on the respiration rate of activated sludge was investigated after a contact time of 3 hours according to OECD guideline 209. The EC50 was above the highest loading rate tested (1000 mg/l).

Key value for chemical safety assessment

EC50 for microorganisms:
1 000 mg/L

Additional information

From the available data for toxicity to microorganism generated from members of the diphenylmethane category it can be concluded by read-across that also Benzyltoluene is devoid of any relevant toxicity to microorganisms.

The key studies from the read-across substances PTE and 1,1 -DPE are GLP-compliant and have a Klimisch score of 1. The key studies are used for chemical safety assessment. The measured value for EC50 of >1000 mg/l is read across to Benzyltoluene. No further testing is required. For detailed read across rationale and justification see section 13, Read across document.