The specific problem addressed by this research is the presence of toxic, persistent organic chemicals in wastewater. In New Jersey, untreated sewage frequently contains on average 64 ng/L of polychlorinated biphenyls (PCBs), which is a thousand times higher than the federal surface water quality standard of 64 pg/L. Wastewater also contains unacceptably high concentrations of dioxins, chlorinated pesticides (such as DDT), brominated flame retardants, and other persistent organic pollutants (POPs). Wastewater and drinking water treatment plants are not designed to remove these POPs. Once they are taken up by organisms, POPs biomagnify, or increase in concentration at higher trophic levels, leading eventually to human exposure when people drink contaminated water or eat contaminated food. We have discovered that sewers already do a fairly good job of destroying many POPs before they reach the wastewater treatment plant, due to microbial action in the anaerobic portions of the sewer. Biological processes occurring in sewers already provide the unintended benefit of waste treatment in the form of reduction of biological oxygen demand (BOD), removal of nitrogen, and total suspended solids (TSS). Now we have discovered that PCBs and polychlorinated dibenzo-p-dioxins and -dibenzofurans (PCDD/Fs) are also detoxified in sewers. The goal of this research is to study the conditions within the sewer that lead to the detoxification of POPs, so that sewer design and management can be optimized, allowing the sewer to serve as an anaerobic pretreatment zone that destroys POPs.
|Effective start/end date||10/1/13 → 9/30/18|