Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

Abiotic degradation:

Indirect photodegradation: According to Q(SAR) data using SRC AOP v1.92, cyclohexyl-methacrylate will be rapidly degraded by photochemical processes after exposure to the air reacting with the photochemically produced hydroxyl radicals (calculated half-life for a 24-hour day and 0.5E06 OH/cm³: 12.9 hours).

Hydrolysis: According to Q(SAR) data using SRC HYDROWIN v1.67, cyclohexyl-methacrylate will be slowly hydrolysed in contact with water (calculated half-life at pH 7 and 25 °C: 274 years; at pH 8 and 25 °C: 27 years).

 

Biodegradation:

Cyclohexyl methacrylate is readily biodegradable according to OECD criteria.

Bioaccumulation:

Available QSAR data using BCFBAF 3.00 and a calulation according to Veith et al. 1979 indicate a low bioaccumulation potential of cyclohexyl methacrylate. In addition, the substance is readily biodegradable and therefore a chronic exposure of aquatic organisms unlikely.

Transport and distribution:

There are no experimental data on transport and distribution of cyclohexyl methacrylate available. The adsorption coefficient and Henry's Law constant can be calculated by validated Q(SAR) such as EPI Suite v4.00. Based on an estimated log Koc of 2.27, no significant adsorption to solid soil phase is expected. Henry's Law Constant was calculated to be 25.96 Pa*m³/mol. Calculation of Henry´s Law constant based on measured water solubility and vapour pressure resulted in a slightly higher value, H = 34.07 Pa*m³/mol. Therefore, cyclohexyl methacrylate is expected to slowly evaporate from the water surface into the atmosphere.

Distribution modeling using Mackay Level I indicates that cyclohexyl methacrylate is likely to partition to the air compartment (90.6 %) with the remainder partitioning into water (7.71 %); negligible amounts are predicted to occur in other environmental compartments (soil, sediment) (Level I Fugacity, 2010). Based on the physical chemical properties of cyclohexyl methacrylate, atmosphere and water are the main target compartments for distribution.