Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

A number of biodegradation screening studies have been carried out using both adapted and unadapted innoculii and in both fresh and saltwater. The key biodegradation screening study clearly indicates that methoxyethanol is readily biodegradable in freshwater with non adapted bacterial populations. A further supporting study indicates that primary degradation can be very rapid, occuring within hours. Additional studies support this conclusion and also provide evidence that adapted bacteria degrade methoxyethanol much more rapidly than unadapted colonies. There is only a single study available in saltwater. This study was performed over only 20 days and indicated degradation of 39% over this timeframe with a non adapted innoculum. Degradation over 28 days may well reach 60% but it is not possible to reach a firm conclusion as to whether methoxyethanol is readily biodegradable from this study. However, the degradation is unlikely to fulfill the 10 day window requirement for ready biodegradation in salt water with unadapted bacteria. It is therefore reasonable to conclude that in salt water, methoxyethanol is inherently biodegradable to unadapted bacteria but readily biodegradable to adapted bacteria. Methoxyethanol is readily biodegradable under all conditions in freshwater environments and in WWTPs.