Potential health effects from exposure to Xylene (Dimethylbenzene) in residential communities experiencing unconventional shale gas extraction and processing operations

Potential health effects from exposure to Xylene (Dimethylbenzene) in residential communities experiencing unconventional shale gas extraction and processing operations. Introduction: Xylene, a product of combustion is found in emissions from unconventional shale gas extraction and processing operations. Residential communities experiencing urban drilling may have an increased risk of exposure to Xylene from inhalation of emissions. Routes of entry into the human body are inhalation, ingestion and absorption. Xylene rapidly spreads throughout the body due to its high solubility in blood. It is highly lipophilic and may be retained in fatty tissues. It can cross the placental and blood-brain barriers (BBB). Objective: To identify potential health effects from Xylene exposure in residential communities experiencing unconventional shale gas extraction and processing. Materials and Methods: A meta-analysis of published literature was performed and articles retrieved from Pubmed (388), Scopus (353), EBSCO, Science Direct and Pneumonet (25). Keywords searched include xylene, dimethylbenzene and health effects of xylene. Abstracts were reviewed and articles pertaining to health effects retrieved in full text. No date restriction on publications was made for articles searched. Xylene was found in mixtures with other volatile organic compounds (Benzene, Toluene and Ethylbenzene), with literature referencing BTEX rather than the individual compounds. Articles that included combined effects of BTEX were excluded. Results: Ambient air monitoring studies identified high concentrations of Xylene at various distances from unconventional shale gas operations. Published literature confirmed exposure to isomers of Xylene was associated with adverse health effects. Residential communities in close proximity to natural gas emissions may experience similar health effects. Short- and long-term health effects associated with Xylene exposure included neurological, respiratory and hematological impairment. Conclusion Short- and long-term exposure to Xylene among residents in close proximity to emissions from unconventional shale gas extraction may have an increased risk of neurological, respiratory and hematological adverse health effects. Children may be at an increased risk due to their unique physiological demand and high body fat.