Ethyl methacrylate

Biodegradation in soil

Description of key information

EMA is readily biodegradable, no further testing is necessary. The assessment for EMA is derived by analogy to MMA.
The following text is taken from the EU ESR on MMA: “For the biodegradation in soil a test with soil microorganisms, performed

according to a US-EPA guideline is available (Hawkins et al., 1993). From the test design (e.g. C14-labelling of the substance), the test could be considered as a simulation test, but the extrapolation to other soil groups needs to be made subject to further comparative research. Due to the highly variable influence of pH, cation exchange capacity or organic carbon content, the biodegradation of MMA remains to be elucidated.
 
Although the greatest amount of the applied MMA evaporated during the test duration of 28 days biological degradation was observed in the above-mentioned test. With the lower test concentration of 100 mg/kg soil the mineralisation was 28%. Although this test is not valid it supports the biodegradation results from the above-mentioned aquatic standard tests on which the calculation of the biodegradation in soil has to be based therefore. With kp soil= 1 l/kg this leads to a rate constant of k = 0.023 d-1for soil.”
 

Key value for chemical safety assessment

Half-life in soil:

30 d

at the temperature of:

295.15 K

Additional information

Using the same TGD defaults with kp soil= 1 l/kg that were used for MMA in the EU risk assessment this leads to a half life [DT50] of 30 d (rate constant k = 0.023 d^-1at 22/25 °C)for soil for EMA. Soil is therefore not a target compartment (see 4.2). EMA is volatile and readily biodegradable. Furthermore, the bioaccumulation study and work done on mammalian metabolism indicates that this is via ubiquitous routes which are known to be present in soil-dwelling organisms.

Overall it is concluded that EMA is rapidly biodegradable in soil.