Occurrence and trends in concentrations of perfluoroalkyl substances (PFASs) in surface waters of eastern China

Abstract

Spatial distributions of perfluoroalkyl substances (PFASs) were investigated in surface waters in Shanghai, Jiangsu and Zhejiang Provinces of eastern China during 2011. A total of 39 samples of surface waters, including 29 rivers, 6 lakes and 4 reservoirs were collected. High performance liquid chromatography/negative electrospray ionization-tandem mass spectrometry (HPLC/(-)ESI-MS/MS) was used to identify and quantify PFASs. Concentrations of PFAS were greater in Shanghai than that in Zhejiang Province. Concentrations of the sum of PFASs (∑PFASs) in Shanghai and Kunshan ranged from 39 to 212 ng L(-1), while in Zhejiang Province, concentrations of ∑PFASs ranged from 0.68 to 146 ng L(-1). Perfluorooctanoic acid (PFOA) was the prevalent PFAS in Shanghai. In contrast, PFOA and perfluorohexanoic acid (PFHxA) were the prevalent PFASs in Zhejiang Province. Concentrations of perfluorooctane sulfonate (PFOS) ranged from <0.07 to 9.7 ng L(-1). Annual mass of ∑PFASs transported by rivers that flow into the East China Sea were calculated to be more than 4000 kg PFASs. Correlation analyses between concentrations of individual PFASs showed the correlation between PFHxA and PFOA was positive, while the correlation between PFHxA and perfluorooctane sulfonamide (FOSA) was negative in Shanghai, which indicated that PFHxA and PFOA have common sources. Principal component analysis (PCA) was employed to identify important components or factors that explain different compounds, and results showed that PFHxA and FOSA dominated factor loadings.

Levels, Isomer Profiles, and Estimated Riverine Mass Discharges of Perfluoroalkyl Acids and Fluorinated Alternatives at the Mouths of Chinese Rivers

“…The high relative ratio of PFOA (83% of total PFASs, Figure 3) indicates its widespread contamination in this region. 27,37 Lower levels of PFOA (57 ng/L) were found in another study in 2011 although the PFHxA levels were comparable (31 ng/L). 27 Among the six other rivers discharging into the East China Sea (Figure 1b), the Yong River showed the highest Σ 10 PFAA levels at 94.4 ng/L.…”

Simultaneous qualitative and quantitative analysis of fluoroalkyl sulfonates in riverine water by liquid chromatography coupled with Orbitrap high resolution mass spectrometry

“…The MDLs were 23-36 pg/L, 7.1 pg/L and 54-62 pg/L by LC-Orbitrap Tribrid HRMS, respectively, while those for the LC-MS/MS quantification method were 16-31 pg/L, 12 pg/L and 41-54 pg/L, respectively (Table 1). Generally, residue concentrations of PFSA analogs in surface water were reported in the range of 0.03-14 ng/L in China [4], 0.03-5.5 ng/L in north of America [39], 0.08-181 ng/L in Europe [13], which could be easily covered by both of the Orbitrap Tribrid HRMS and LC-MS/MS trace quantification dynamic ranges (0.1-50 ng/mL). Also, all analytes were calibrated with good coefficients of determination (R 2 ) all ≥0.9990 for Orbitrap Tribrid HRMS and ≥0.9982 for LC-MS/MS at 1/x weighting (Table S4).…”

“…For example, perfluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHxS) and PFOS were present with a concentration ranged of 0.94-13.7 ng/L in Taihu Lake [3]. A range of 0.03-89 ng/L PFOS was detected in river water of eastern China [4]. In Atlantic, Indian and Pacific oceans, PFBS, PFHxS and PFOS occurred in a range of 20.0-45.4 pg/L, 6.65-32.4 pg/L and 88. pg/L respectively [5].…”

“…Alkaline methanol containing 0.1% NH 4 OH was further used to neutralize and to elute the fluoroalkyl sulfonates from the WAX columns. The eluent volume (2 mL, 4 mL and 6 mL) was optimized in order to recovery target analytes as much as possible.…”

“…The wide usages of the chemicals in industry and daily necessities, such as surfactants, textile, aqueous fire-forming foam, mist suppressant and coatings, have resulted in their inevitable release into the environment since 1950s [2]. Particularly, linear and branched perfluorooctane sulfonate (PFOS) isomers as well as other perfluoroalkyl sulfonate analogs (PFSAs) have become world-wide contaminants due to the persistent and long-range transport characteristics as well as their ubiquitous presence in aqueous environmental com-partments [3][4][5][6][7]. For example, perfluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHxS) and PFOS were present with a concentration ranged of 0.94-13.7 ng/L in Taihu Lake [3].…”