Developing and Validating Genetic Catabolic Probes for Monitored Natural Attenuation of 1,4-Dioxane with a One-Year Timeframe.

摘要

Remediation of aquifers contaminated with 1,4-dioxane (dioxane) is a difficult task due to its extremely hydrophilic nature. Monitored natural attenuation (MNA), which relies primarily on biodegradation, is often the most cost-effective approach to manage large and dilute groundwater plumes of primary pollutants, such as those formed by dioxane. However, improved forensic tools are needed to ensure biodegradation is occurring at impacted sites. During this one-year project, catabolic biomarkers of high selectivity and sensitivity were developed to target (until now elusive) dioxane/tetrahydrofuran soluble di-iron monooxygenase genes using Taqman chemistry. Further, dioxane degradation activity observed in microcosms prepared with groundwater samples and aquifer materials from multiple sites was found to be significantly correlated with the abundance of thmA/dxmA genes, suggesting the usefulness of this probe to assess feasibility of MNA/bioremediation and estimate degradation rates.