Researchers say the discovery could help lead to more effective means for treatment of water contaminated by this highly-soluble chemical, known for its resistance to conventional water purification and treatment efforts.
"Many products we use every day use a mixture of more than 100 chemicals, and we don’t realize that some of them contain traces of 1,4-dioxane that are washed down our drains and released into the environment," said Dr. Mengyan Li, assistant professor of chemistry and environmental science at NJIT.
"A one-time exposure isn’t extremely toxic, but contamination in drinking water can have a chronic effect that raises cancer risk.
"What we are doing is studying microbes that actually consume this contaminant as their food," Li explained.
Li’s lab was able to identify and characterize the critical role of one enzyme, propane monooxygenase, which leads the way in decomposing 1,4-dioxane’s stable circular structure so it can be converted to fuel for the bacteria.
According to water quality testing data from local utilities throughout the U.S. between 2010 and 2015, 7 million people in 27 states are served by public water systems with a higher 1,4-dioxane concentration in their drinking water than 0.35 parts-per-billion (ppb)—a concentration level that can marginally increase cancer risk.
"But this isn’t just an issue in Long Island and New Jersey…it can be an issue globally because everyone uses products like shampoos and detergents almost every day."
Along with the rise of the chemical released into the environment, estimated cleanup costs in hot-spot locations like Long Island have also risen to such a degree due to a lack of cost-effective and environmentally safe approaches to treat the problem.
Other efforts that apply absorbents to trap water contaminants typically require additional treatment to prevent land disposal problems where the concentrated chemical is released back into the environment.
More information: Daiyong Deng et al. A Novel Propane Monooxygenase Initiating Degradation of 1,4-Dioxane by Mycobacterium dioxanotrophicus PH-06, Environmental Science & Technology Letters (2017).