4-chloro-α,α,α-trifluorotoluene

Biodegradation in water and sediment: simulation tests

Description of key information

No studies are available, however the half-life in water and sediment were taken from two aquatic biodegradation studies where it was observed that after one day from the starting of the test, less than 50% of the test item was recovered in the test system. The half-life value used in the CSR is not therefore due to biodegration, but to the volatilization from the water phase.

Key value for chemical safety assessment

Half-life in freshwater:

1 d

at the temperature of:

20 °C

Half-life in freshwater sediment:

1 d

at the temperature of:

20 °C

Additional information

In accordance with column 2 of REACH annex IX, further degradation testing does not need to be conducted as the chemical safety assessment does not indicate a need for further investigation. In fact, the substance is slightly soluble in water and it is very volatile.

Two studies are available showing that it was not possible to assess the biodegradation of the test item in water under either aerobic and anaerobic conditions because of the high volatility of the PCBTF. In view of these results it appears unlikely that PCBTF would remain in natural, aerated, aquatic environmental for any appreciable lenght of time. The half-life value used in the CSR is not therefore due to biodegration, but to the volatilization of PCBTF from the water phase.