Xylene Marine Contamination

Xylene marine contamination is the presence of xylene, a dimethylbenzene aromatic hydrocarbon, in coastal and port waters from petroleum and petrochemical operations. Xylene is one of the BTEX group (benzene, toluene, ethylbenzene, xylene), reaching the sea through tanker loading vapors, ballast and bilge discharge, refinery effluent, and oil spills. It exists as three isomers (ortho, meta, para) plus ethylbenzene. Being volatile and moderately water-soluble, it evaporates and biodegrades faster than heavier oil fractions, but acute exposure is toxic to fish and invertebrates and it is a tracked petroleum-contamination marker in harbor sediments.