Registration Dossier

Diss Factsheets

Ecotoxicological information

Toxicity to microorganisms

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

Testing on other microorganisms showed similar EC50 results to other testing.
2 studies provide the weight of evidence argument for the figures quoted:
Marchetti (1978) found an 48hr EC50 of 0.31 mg TEL/L
Wong et al (1979) found an 48hr EC50 of 0.078 mg TEL/L
The values obtained are of a similar level to the testing on Fish, aquatic invertebrates and algae, therefore the values quoted are reasonable

Key value for chemical safety assessment

EC50 for microorganisms:
0.078 mg/L

Additional information

Based on a reduction of oxygen uptake by marine bacterial mixed cultures, a 48-h EC50 value of 0.31 mg TEL/L was determined. In a field trial with zooplankton and algae at a TEL concentration of 0.078 mg/L, all activity was found to be terminated within 48 hours.[r1] 

The following information is taken into account for effects on aquatic micro-organisms for the derivation of PNEC:

Testing on other microorganisms showed similar EC50 results to other testing.

Two studies provide the weight of evidence argument for the figures quoted:

Marchetti (1978a) found a 48-h EC50 of 0.31 mg TEL/L.

Wong and Hincks (1979) found a 48-h EC50 of 0.078 mg TEL/L

The values obtained are of a similar level to the testing on fish, aquatic invertebrates and algae.

Value used for CSA:

EC50/LC50 for aquatic micro-organisms: 0.078 mg/L