Formation potential of disinfection byproducts during chlorination of petroleum hydrocarbon-contaminated drinking water.

Recent leaks of underground fuel storage tanks in the Pearl Harbor region have led to direct release of un-weathered petroleum hydrocarbons (PHCs) into drinking water sources, which then directly underwent chlorination disinfection treatment. Since the control of disinfection byproducts (DBPs) traditionally focuses natural organic matters (NOM) from source water and little is known about the interactions between free chlorine and un-weathered PHCs, laboratory chlorination experiments in batch reactors were conducted to determine the formation potential of DBPs during chlorination of PHC-contaminated drinking water. Quantitative analysis of regulated DBPs showed that significant quantities of THM4 (average 3,498 μg/L) and HAA5 (average 355.4 μg/L) compounds were formed as the result of chlorination of un-weathered PHCs. Amongst the regulated DBPs, THM4, which were comprised primarily of chloroform and bromodichloromethane, were more abundant than HAA5. Numerous unregulated DBPs and a large diversity of unidentified potentially halogenated organic compounds were also produced, with the most abundant being 1,1-dichloroacetone, 1,2-dibromo-3-chloropropane, chloropicrin, dichloroacetonitrile, and trichloracetonitrile. Together, the results demonstrated the DBP formation potential when PHC-contaminated water undergoes chlorination treatment. Further studies are needed to confirm the regulated DBP production and health risks under field relevant conditions. [Display omitted] • Regulated DBPs were produced when jet fuel petroleum hydrocarbons reacted with free chlorine. • Chloroform was the most abundant regulated THM compound, followed by bromodichloromethane and dibromochloromethane. • Monobromoacetic acid was the most abundant regulated HAA, followed by dibromoacetic acid and monochloroacetic acid. • A large diversity of unregulated DBPs, including a complex group of high-molecular-weight compounds, were also detected. Synopsis: Petroleum hydrocarbon leakage into drinking water aquifers is becoming more and more prevalent. This research investigates the formation of disinfection byproducts through chlorination of petroleum hydrocarbons in water. [ABSTRACT FROM AUTHOR]