AN ECOLOGICAL RISK ASSESSMENT OF THE POTENTIAL EFFECTS OF PFOS ON INVERTIVOROUS BIRDS NESTING NEAR TWO POINT SOURCES IN TEXAS

Abstract

Per- and polyfluoroalkyl substances (PFAS) are a group of synthetic organic compounds that have a large number of congeners and are used as surfactants in a wide range of consumer products, including firefighting foams, pesticides, and cleaning supplies. The two main point sources of environmental contamination of PFAS are releases from manufacturing facilities and from the use of firefighting foams at fire training facilities, airports, military bases, and fire suppression sites. Two potential point sources of PFAS in College Station, TX occur along White Creek: the Brayton Fire Training Field (BFTF) and the Easterwood Airport. The goal of this ecological risk assessment is to determine the magnitude and effects that PFAS coming from these two sources may pose on the reproductive success of Carolina Wrens, an indicator species for invertivorous birds. Field-collected concentrations of PFAS around the facilities and literature-based equations and values were used to assist in the estimation of exposure of PFAS to Carolina Wrens. Specifically, a total daily intake value of PFOS (0.006 mgPFOS/kgbody/day) was calculated and then compared to a lab-derived no-observed-adverse-effect-level (0.77 mgPFOS/kgbody/day) from the literature to yield a risk quotient (0.008). The risk quotient in this ecological risk assessment was well below 1, indicating that PFOS does not represent a risk for negative effects on the reproduction of Carolina Wrens nesting around the Easterwood Airport and Brayton Fire Training Field.