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Administrative data

Link to relevant study record(s)

Description of key information

No toxicokinetic data are available for 2 -methylbut-2 -ene (2M2B), however its olefinic nature suggests it would be metabolised via an epoxide intermediate in vivo. A log Kow <3 indicates no potential for bioaccumulation.

Key value for chemical safety assessment

Bioaccumulation potential:
no bioaccumulation potential

Additional information

No toxicokinetic studies have been conducted with 2 -methylbut-2 -ene (2M2B) in animals or humans. Being an olefin, 2M2B would be expected to form an epoxide intermediate.  Mice are likely to form the epoxide intermediate (P450 enzyme mediated) at a higher rate than rats and this would be hydrolyzed by the enzyme epoxide hydrolase at a lower rate in mice than in rats. These metabolic differences between mice and rats would result in higher epoxide levels in mice compared with rats at equivalent 2M2B exposure concentrations. This might explain the higher levels of micronucleated erythrocytes in the bone marrow of mice compared with rats when exposed to 10,000 ppm 2-methylbut-2-ene (see CSR section 5.7.1.2).