Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

The test substance is demonstrated not to be readily biodegradable. Slow degradation was observed in natural surface water, the DT50 values ranging between 179 and 464 days depending on the component under consideration and the initial concentration in surface water. Although abiotic degradation was found to contribute to a limited extent to the total observed degradation in this study, biodegradation was relatively more important.

Additional information

Based on the 28-day ready biodegradability test using activated sludge (OECD guideline 301 F), it was concluded that the test substance was not readily biodegradable under the conditions of the test.

The degradation of the test substance was further studied in an OECD 309 study using natural surface water. During the 60-day study, 7 representative components of the UVCB were monitored analytically over a time frame of 60 days. The DT50 values for the representative components were estimated to range overall between 179 and 464 days, depending on the initial concentration of the test item. Based on the results of this study, the substance can be concluded to (bio)degrade very slowly (i.e. the substance is not rapidly degradable). A comparison of recovery over time in biologically active samples with that observed in abiotic controls learned that biodegradation contributed most to the total observed degradation, whereas abiotic degradation only contributed to a limited extent.