Chemists at the University of Texas at Arlington have published a new study that indicates that highly variable contamination events registered in and around unconventional oil and gas developments are the result of operational inefficiencies and not inherent to the extraction process itself.The study, published today as "Point source attribution of ambient contamination events near unconventional oil and gas development" in Science of the Total Environment, found highly variable levels of ambient BTEX, or benzene, toluene, ethyl benzene, and xylene compounds, in and around fracking gas drilling sites in the Eagle Ford shale region in South Texas. BTEX compounds in high concentrations can be carcinogenic and have harmful effects on the nervous system.