1,2-Butylene oxide (1,2-Epoxybutane)

1,2-Butylene oxide is produced by the epoxidation of 1-butene with peracids or by chlorohydrin process [1]. It is used as a stabilizer for chlorinated solvents, as a chemical intermediate in surfactant and polyol synthesis, and as a monomer in ring-opening polymerization for polyether production [2]. Like other simple 1,2-epoxides (ethylene oxide, propylene oxide), it forms as an intermediate in the oxidative metabolism of butene in combustion processes [1]. Production scale is significant — it is a volume intermediate chemical in the specialty chemicals sector [2].

Occupational exposure in 1,2-butylene oxide production, chlorinated solvent stabilization, and polyol synthesis [1]. Workers in chemical plants using it as an intermediate face inhalation and dermal exposure [2].

1,2-Butylene oxide's three-membered epoxide ring opens readily with nucleophilic attack from DNA bases at N-7 guanine and N-3 adenine positions, forming hydroxybutyl DNA adducts [1]. Hemoglobin adducts (N-hydroxybutylvaline) serve as biomarkers. Nasal turbinate tumors and forestomach carcinomas in rodents [2]. EPA Group B2 probable carcinogen [1].

Chemical plant workers in butylene oxide synthesis and polyol production [1].

1. Engineering controls: closed systems, local exhaust ventilation [1]. 2. NIOSH-approved organic vapor respirators [2].