Advances in bioremediation of 1,4-dioxane-contaminated waters

1,4-Dioxane is a contaminant of emerging concern that has been found widespread in groundwater, surface water, and drinking water environments. Many states are implementing lower regulatory advisory levels based on the toxicological profile of 1,4-dioxane and the potential public health risks. However, the unique chemical properties of 1,4-dioxane, such as high water solubility, low Henry's law constant, and importantly, the co-occurrence with chlorinated solvents and other contaminants, increase the challenges to efficiently cleanup 1,4-dioxane. This review summarizes currently available chemical and physical 1,4-dioxane treatment technologies and focuses on recent advances in bioremediation and monitoring tools. We also include laboratory studies and field applications to propose the next steps in 1,4-dioxane bioremediation research. It is important to provide useful references to change the industrial and regulatory perception of 1,4-dioxane biodegradability, to understand treatment mechanisms especially in contaminant mixtures, and to direct research for meeting practical needs.