Occurrence and source apportionment of perfluoroalkyl acids (PFAAs) in the atmosphere in China

Deming Han,Xue Hu,Shuang Fu,Xufeng Zhang,Jinping Cheng,Cheng Huang,Yong Zhou,Hao Xu,Xiaojia Chen,Xiqian Huang,Haoxiang Liao,Yingge Ma,Shan Liang

doi:10.5194/acp-19-14107-2019

Abstract

Abstract. Perfluoroalkyl acids (PFAAs) are a form of toxic pollutant that can be transported across the globe and accumulated in the bodies of wildlife and humans. A nationwide geographical investigation considering atmospheric PFAAs via a passive air sampler (PAS) based on XAD (a styrene–divinylbenzene copolymer) was conducted in 23 different provinces/municipalities/autonomous regions in China, which provides an excellent chance to investigate their occurrences, spatial trends, and potential sources. The total atmospheric concentrations of 13 PFAAs (n=268) were 6.19–292.57 pg m−3, with an average value of 39.84±28.08 pg m−3, which were higher than other urban levels but lower than point source measurements. Perfluorooctanoic acid (PFOA) was the dominant PFAA (20.6 %), followed by perfluorohexanoic acid (PFHxA), perfluorooctane sulfonate (PFOS), and perfluoroheptanoic acid (PFPeA). An increasing seasonal trend of PFAA concentrations was shown as summer < autumn < spring < winter, which may be initiated by stagnant meteorological conditions. Spatially, the content of PFAAs displayed a declining gradient trend of central China > northern China > eastern China > north-eastern China > south-western China > north-western China > southern China, and Henan contributed the largest proportion of PFAAs. Four sources of PFAAs were identified using a positive matrix factorization (PMF) model, including PFOS-based products (26.1 %), products based on PFOA and perfluorononanoic acid (PFNA; 36.6 %), degradation products of fluorotelomer-based products (15.5 %), and an unknown source (21.8 %).

Highlights

Perfluoroalkyl acids (PFAAs) are a class of ionic polyfluoroalkyl substances (PFASs), which have excellent characteristics in terms of chemical and thermal stability, high surface activity, and water and oil repulsion (Lindstrom et al, 2011;Wang et al, 2014)
The long–chain perfluoroalkyl carboxylic acids (PFCAs) concentrations were 25.6±18.9 pg/m3, which were significantly higher than the short–chain (C ≤ 6) concentrations (12.3±10.9 pg/m3) (p
This study found generally higher PFAAs abundances compared to measurement in Canada (Gewurtz et al, 2013), which may be attributed to the relative high abundance of industrial and domestic emissions in

Summary

Introduction

Perfluoroalkyl acids (PFAAs) are a class of ionic polyfluoroalkyl substances (PFASs), which have excellent characteristics in terms of chemical and thermal stability, high surface activity, and water and oil repulsion (Lindstrom et al, 2011;Wang et al, 2014). They are applied to a wide variety of domestic and industrial products such as textiles, oil and liquid repellents, firefighting foam, pesticides, and food packaging materials (Xie et al, 2013;Wang et al, 2014). This especially applies to perfluorooctanoic acid (PFOA) and perfluorohexane sulfonate (PFHxS) for which have been regulated in numerous countries, while perfluorooctane sulfonate (PFOS) have been added to Annex B of the Stockholm Convention in 2009 (Johansson et al, 2008)

Objectives

Methods

Results

Conclusion