When styrene is heated, exposed to light, or in the presence of a peroxide catalyst, it undergoes polymerization to form polystyrene, a versatile material used in the manufacture of plastics, synthetic rubber, thermal insulation, and packaging. Although polystyrene has many beneficial commercial applications, the styrene monomer is a classified mutagen and a suspected carcinogen. It is highly toxic to aquatic life, although its half-life is less than two days in water. There are several microorganisms that are capable of initiating styrene biodegradation, and metabolism proceeds via one of two known pathways; the principal reaction may either be an ethylene side-chain monooxygenation ([http://www.ncbi.nlm.nih.gov/pubmed/8919815|Cox et al., 1996]) or a 2,3-dioxygenation ([http://www.ncbi.nlm.nih.gov/pubmed/8017910|Warhurst et al., 1994]).