2-phenoxyethanol

Biodegradation in water: screening tests

Description of key information

2-phenoxyethanol was found to be readily biodegradable.

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Additional information

The ready biodegradability of 2-phenoxyethanol was tested in several aerobic studies. The first key study reports a DOC Die Away Test conducted according to OECD 301A and EPA OPPTS 835.3110 (BASF AG, 2002). The biodegradation of 20 mg/L DOC (nominal) of the test substance was monitored for 15 days. After 15 days, 90 to 100% of the initial 2-phenoxyethanol (purity >99%) was degraded, the 10-day window was met. The second key study on ready biodegradability of 2-phenoxyethanol was conducted according to OECD guideline 301F (Manometric Respiratory Test), and revealed a degradation rate 2-phenoxyethanol (purity 94%) based on oxygen consumption of 90% after 28 days, the 10-day window was met (The Dow Chemical Company, 1999). Two supporting studies applied the DOC Die Away Test (OECD 301A) and the Closed Bottle Test (OECD 301D) with the result of 96% DOC removal and 66% oxygen consumption, respectively. In both studies the 10-day window was met. Two supporting studies testing inherent biodegradability (Zahn-Wellens-Test, OECD 302B) showed a TOC removal rate of 80-90% and 99% respectively, in both cases, the window of >70% TOC removal within 10 days was not met. In conclusion, 2-phenoxyethanol can be regarded as readily biodegradable as >60% biodegradation was achieved within 10 days of the start of biodegradation with conducted tests designed for ready biodegradability.