Unregulated Active and Closed Textile Mills Represent a Significant Vector of PFAS Contamination into Coastal Rivers

Despite
concerns over the ubiquity of per- and polyfluoroalkyl
substances (PFAS), little is known about the diversity of their sources
to surface waters and their seasonal dynamics. Frequent use of PFAS
in textiles means that both active and closed textile mills require
evaluation as PFAS sources. We deployed passive samplers at seven
sites in an urban river and estuary adjacent to textile mills in Southern
Rhode Island (USA) over 12 months. We estimated monthly mass flows
(g month–1) of perfluorohexanoic acid (45 ±
56) and perfluorooctanoic acid (30 ± 45) from the upstream river
influenced by an active mill. Average mass flows were 73–155%
higher downstream, where historical textile waste lagoons contributed
long-chain perfluoroalkyl acids. Mass flows of perfluorononanoic acid
increased from 7.5 to 21 g month–1 between the upstream
and downstream portions of the rivers. Distinct grouping of the two
main PFAS sources, active textile mills and historical waste lagoons,
was identified using principal component analysis. Neither suspect
screening nor extractable organofluorine analysis revealed that measurable
PFASs were missing beyond the targeted compounds. This research demonstrates
that both closed and active textile mills are important ongoing PFAS
sources to freshwater and marine regions and should be further evaluated
as a source category.