Wastewater Treatment Plant and Landfills as Sources of Polyfluoroalkyl Compounds to the Atmosphere

Abstract

Polyfluoroalkyl compounds (PFCs) were determined in air around a wastewater treatment plant (WWTP) and two landfill sites using sorbent-impregnated polyurethane foam (SIP) disk passive air samplers in summer 2009. The samples were analyzed for five PFC classes (i.e., fluorotelomer alcohols (FTOHs), perfluorooctane sulfonamides (FOSAs), sulfonamidoethanols (FOSEs), perfluoroalkyl sulfonic acids (PFSAs), and perfluoroalkyl carboxylic acids (PFCAs)) to investigate their concentration in air, composition and emissions to the atmosphere. ∑PFC concentrations in air were 3-15 times higher within the WWTP (2280-24 040 pg/m(3)) and 5-30 times higher at the landfill sites (2780-26 430 pg/m(3)) compared to the reference sites (597-1600 pg/m3). Variations in the PFC pattern were observed between the WWTP and landfill sites and even within the WWTP site. For example, FTOHs were the predominant PFC class in air for all WWTP and landfill sites, with 6:2 FTOH as the dominant compound at the WWTP (895-12 290 pg/m(3)) and 8:2 FTOH dominating at the landfill sites (1290-17 380 pg/m(3)). Furthermore, perfluorooctane sulfonic acid (PFOS) was dominant within the WWTP (43-171 pg/m(3)), followed by perfluorobutanoic acid (PFBA) (55-116 pg/m(3)), while PFBA was dominant at the landfill sites (101-102 pg/m(3)). It is also noteworthy that the PFCA concentrations decreased with increasing chain length and that the emissions for the even chain length PFCAs outweighed emissions for the odd chain length compounds. Furthermore, highly elevated PFC concentrations were found near the aeration tanks compared to the other tanks (i.e., primary and secondary clarifier) and likely associated with increased volatilization during aeration that may be further enhanced through aqueous aerosol-mediated transport. ∑PFC yearly emissions estimated using a simplified dispersion model were 2560 g/year for the WWTP, 99 g/year for landfill site 1, and 1000 g/year for landfill site 2. These results highlight the important role of WWTPs and landfills as emission sources of PFCs to the atmosphere.

Field study on the uptake and translocation of perfluoroalkyl acids (PFAAs) by wheat (Triticum aestivum L.) grown in biosolids-amended soils

“…It is possible that PFAAs in the soils evaporate into the ambient air and enter plants via gaseous uptake, contributing to their accumulation in the above-ground part of wheat, because PFAAs can be detected in the atmosphere (Li et al, 2011;Ahrens et al, 2011), though they do not readily volatize ). An alternative pathway for PFAAs transport is via aerial transport of volatile PFAA precursors with subsequent oxidation of the plantbound PFAA precursors, such as fluorotelomer alcohols (FTOHs) or 2-(N-ethylperfluorooctanesulfonamido) acetic acid (N-EtFO-SAA), to form PFAAs (Yoo et al, 2011).…”

Methodology for studying biotransformation of polyfluoroalkyl precursors in the environment

“…Soil is the primary deposit medium of volatile precursors through atmospheric deposition, while sewage sludge and river sediment are important sinks of PFASs in aqueous systems from household and industry emissions [15][16][17]. To obtain knowledge on the specific microorganisms responsible for the polyfluoroalkyl precursor biotransformation processes, microbial consortium or pure bacterial cultures from soil and sewage sludge were isolated and used [30][31][32].…”

“…Both fluorotelomer-based (FT) precursors (e.g., FTOHs and FTIs) and perfluoroalkane sulfonamido derivatives, including N-ethyl perfluorooctane sulfonamide (N-EtFOSA) and N-ethyl perfluorooctane sulfonamidoethanol (N-EtFOSE), were found in ambient air particles [13][14][15]. Fluorotelomer alcohols, monosubstituted and disubstituted PAPs, and perfluorooctane sulfonamidoacetic acid (FOSAA) analogues have frequently been detected in wastewater-treatment plant (WWTP) effluent, activated sludge and marine sediments [15][16][17]. Elevated PFAS concentrations found in effluents compared with those in influents may further indicate contributions of polyfluorinated-precursor biodegradation in the WWTPs [18].…”

Perfluoroalkyl substances in the Daling River with concentrated fluorine industries in China: seasonal variation, mass flow, and risk assessment

“…As a type of emerging persistent and bioaccumulative environmental contaminants, they have received great scientific concerns due to their ubiquitous environmental distribution (Ahrens 2011;Ahrens et al 2011;Bao et al 2010;Houde et al 2011;Naile et al 2010;Young et al 2007) as well as their potential toxicity to ecological system and human (Lau et al 2004;Olsen et al 2009). Perfluorooctane sulfonate (PFOS) and related substances have been restricted by EU Directive 2006/122/EC and listed as persistent organic pollutants under the Stockholm Convention in recent years (EPC 2006;UNEP 2009).…”