Land application of wastewater effluent, known as beneficial wastewater reuse, plays an important role in reducing fresh water use for agriculture. However, many emerging contaminants, such as pharmaceuticals and personal care products (PPCPs) and per-fluoroalkyl substances (PFAS), remain in treated wastewater effluent and are inadvertently introduced to agroecosystems when the treated wastewater is spray-irrigated. Therefore, the potential for beneficial wastewater reuse to affect groundwater quality is important to understand, especially if the groundwater is used as a potable drinking water source, as some PPCPs are known or suspected endocrine disrupters, and PFAS compounds are known carcinogens. Here, we present the results of two studies that have been conducted at the Penn State beneficial wastewater reuse site, known as the “Living Filter”. The site has been spray-irrigated with 100% of Penn State’s treated wastewater since the early 1980s. Despite PPCPs and PFAS being described as “emerging” contaminants, they are not necessarily “new” chemicals. Rather, many compounds in this category of contaminants have been around for decades, but their human and ecological health implications have only recently become a focus of concern. To understand how nearly 40 years of irrigation activities at the site have impacted the groundwater quality, we conducted bi-monthly sampling at 13 monitoring wells at the site over two different 14-month periods, in addition to sampling the influent and effluent of the wastewater treatment plant. Overall, PPCPs and PFAS were found across the field site, and generally increased in the direction of groundwater flow. Relative to their concentrations in the treated wastewater, PPCPs in the groundwater monitoring wells were approximately two orders of magnitude smaller. However, PFAS concentrations in the monitoring wells were on the same order of magnitude as those found in the treated wastewater. Despite the occurrence of these chemicals in the groundwater, data suggest that the soil profile at the Living Filter site has been able to serve an effective biogeochemical filtering function for a suite of emerging contaminants, with risk quotients calculated for PPCPs all indicating low human health risk, and PFAS concentrations present below the recommended Lifetime Health Advisory levels.

From wastewater to groundwater: Fate of pharmaceuticals and PFAS in beneficial reuse systems and implications for human health

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.