Characterization of the Potential Long-Term Impact from Sedimentary PFAS at a Historically Contaminated Textile Waste Site

TL;DR

This study examines how PFAS contamination from old textile waste ponds in Rhode Island could persistently pollute nearby water bodies over time.

Contribution

The study provides a detailed assessment of PFAS mobility and long-term release potential from contaminated sediment using field and lab methods.

Findings

Retention pond 1 had high PFAS levels, with up to 26 ng/L PFOA in water and 74 ng/g PFTrDA in sediment.

PFAS partitioning coefficients suggest some compounds may remain in sediment for over 100 years.

Estimated PFAS fluxes from sediment to water range from 5 to 228 μg m–2 year–1.

Abstract

Per- and polyfluoroalkyl
substances (PFAS) are pervasive pollutants
at historically contaminated sites throughout the United States and
beyond. Two such sites in Rhode Island, USA, are textile-mill-associated
waste retention ponds known to introduce PFAS contamination to the
adjacent river, estuary, and eventually the Atlantic Ocean. Here,
we thoroughly investigated the retention ponds as a long-term source
of PFAS via water passive sampling, sediment coring, and laboratory-derived
partitioning coefficients, K
d, with field
sediment and water. Additional studies were performed to assess the
mobility and estimate the mass fluxes of PFAS from sediment to water.
Retention pond 1 was more contaminated (up to 26 ng/L PFOA in water
and 74 ng/g PFTrDA in sediment). Derived log K
d values ranged from 1 to 5 for most PFAS, indicating a shift
from relative mobility to high storage potential in sediment. Estimated
loss fluxes from the sediment varied between 5 and 228 μg m–2 year–1, resulting in desorption
times from 3 years for FPeSA to >100 years for FOSA. The combined
evidence suggests that this textile mill retention pond, if left untreated,
constitutes a source of long-term contamination to the river.

Figures