University of New Hamshire
Alexandria Hidrovo received her Bachelors of Science in Environmental Engineering at the University of New Hampshire. She is currently in her 2nd year of graduate school pursing a Master of Science degree in Environmental Engineering. In 2019, she was awarded a National Science Foundation (NSF) Graduate Research Fellowship (GRF) on the topic of occurrence, removal, and fate of pharmaceuticals and personal care products (PPCPs) within wastewater treatment facilities.
The fate and removal of pharmaceuticals and personal care products within wastewater treatment facilities discharging into New Hampshire’s Great Bay Estuary
Pharmaceuticals and personal care products (PPCPs) are contaminants of emerging concern that derive primarily from combined sewer overflows and discharges from industrial and municipal wastewater treatment facilities (WWTFs). One major concern of PPCPs in surface water is their potential toxicity to sensitive receptors, such as aquatic organisms, at low concentrations. Some PPCPs may exhibit a wide range of health or behavioral effects in aquatic life (e.g., neural, instinct response, reproductive) at part per billion levels while others may bioaccumulate, amplifying effects up the food chain. The Great Bay National Estuarine Research Reserve in New Hampshire supports 169 bird, fish, and plant species; therefore, understanding the sources and fate of PPCPs in its contributing tributaries is essential to protecting its delicate ecosystem. Conventional WWTFs have four stages of treatment (preliminary, primary, secondary, disinfection), but most PPCP removal occurs during secondary treatment through biodegradation by a diverse aerobic microbial community. Recent studies have shown secondary treatment designed to achieve low effluent nutrient levels (nitrogen and phosphorous) have a positive relationship on PPCP removal. This project was split into two sampling phases; mid-March 2019 (phase-1) and mid-July 2019 (phase-2). In collaboration with six local WWTFs for phase-1, we have: (1) investigated concentrations for 21 PPCPs occurring in WWTFs discharging into the Great Bay estuary and (2) examined differences in biological/secondary treatment processes influencing removal of select PPCPs. The selected WWTFs represent a range of different secondary treatment designs (i.e., conventional activated sludge, 4-stage Bardenpho, aerated lagoons, and oxidation ditch) and disinfection methods (i.e., chlorination/dechlorination and ultraviolet (UV) light disinfection). Phase-2 focused on four of the six WWTFs showing low and high PPCP removal utilizing the same disinfection method (chlorination/dechlorination). Keeping the disinfection method constant allows for better comparison of the secondary treatment methods. Also, one WWTF upgraded their secondary treatment for better nutrient removal in between phases. Therefore in phase-2 we will: (1) develop a mass balance of PPCPs into and out of the facilities while comparing concentrations/detection to phase-1, (2) examine if the secondary treatment upgrade improves the removal of select PPCPs and (3) connect PPCP biotransformation rate constants to microbial metagenomic potential. Factors such as operational conditions, nutrient removal, and microbial community composition at each plant will also be considered in context with PPCP removal. In phase-1, all 21 PPCPs were detected in the influent and/or effluent samples for each WWTF. The PPCPs with the highest percent removal averaged across all the WWTFs included acetaminophen, cotinine, DEET, and ciprofloxacin while lower percent removals were observed for methadone, TDCPP, carbamazepine, and TCPP. Among the 21 PPCPs detected, 9 were also detected downstream at a surface water sample near the mouth of the Great Bay estuary. In phase-2, we expect to see an increase in PPCP removal due to warmer temperatures increasing microbial activity within the WWTFs. Additionally, four surface water samples will be taken in early August 2019 to further examine PPCP distribution within the Great Bay. These data are providing new insight into PPCP occurrence, removal, and fate in New England.