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Environmental fate & pathways

Endpoint summary

Administrative data

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Additional information

Based on the available studies on biodegradation and the relatively low sorption potential, 1-methylpiperazine is expected to be non-persistent in water, soil or sediment and for more than 99% removed from waste water in a sewage treatment plant.

The available biodegradation studies show that when using adapted sludge or sessile microorganisms (which settled on glass beads during flow through of river water containing low µg/L test substance) as inoculum in a closed bottle test. In these tests, the microorganisms in the closed bottle are capable of growing at high rates because N-methylpiperazine was degraded within a week.

Based on this high observed degradation rate it is very likely that the number of competent microorganisms in the old OECD 302b studies and activated sludge used for the GLP test was not sufficient. This indicates that competent micro-organisms capable of degrading 1 -methylpiperazine are not wide dispersively available, thus that 1-methylpiperazine should be considered to be inherently biodegradable.