| 1. |
- Chen, S., et al.
(författare)
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Current Pollution Status and Environmental Behaviors of PFASs in Soil; [土壤中全氟和多氟烷基化合物的污染现状及环境行为]
- 2021
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Ingår i: Research of Environmental Sciences. - 1001-6929. ; 34:2, s. 468-478
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Tidskriftsartikel (refereegranskat)abstract
- Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are a group of emerging persistent organic pollutants. PFASs in soil can affect water quality when they leach into groundwater, and threaten the ecosystem and human health through trophic transfer and magnification along the terrestrial food chains, which make them one of the hot research topics in environmental chemistry. At present, the content of less than 1% of the total fluorinated compounds in the soil can be accurately determined, and the content is at the ng/g level. The research areas in China are concentrated in the east and the surrounding areas of fluorochemical plants. The main compounds of PFASs in soil are PFOS and PFOA. The physicochemical properties of soil, species of PFASs and human activities are the main factors influencing the occurrence of PFASs in different types of soil. In addition to the direct release and atmospheric transport during the production and use of fluorinated chemicals, PFASs precursor conversion in soil is also an important source of PFASs. Adsorption-desorption is the major process affecting the transport of PFASs in soil. Studies also demonstrate that the transport and accumulation of PFASs in soil are affected by various factors such as the chain-length and functional groups of PFASs, soil physicochemical properties and microorganisms. In consideration of the research status, further development of extraction and analytical methods is needed to cover a wider range of PFASs. Attention can be paid to the changing trend and mechanism of novel PFASs in soil. The bioaccessibility and bioavailability study of PFASs in soil are also needed for ecological and human health risk assessment.
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| 2. |
- Jiao, Enmiao, et al.
(författare)
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A pilot study on extractable organofluorine and per- and polyfluoroalkyl substances (PFAS) in water from drinking water treatment plants around Taihu Lake, China : what is missed by target PFAS analysis?
- 2022
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Ingår i: Environmental Science. - : Royal Society of Chemistry. - 2050-7887 .- 2050-7895. ; 24:7, s. 1060-1070
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Tidskriftsartikel (refereegranskat)abstract
- Per- and polyfluoroalkyl substances (PFAS) have raised concerns due to their worldwide occurrence and adverse effects on both the environment and humans as well as posing challenges for monitoring. Further collection of information is required for a better understanding of their occurrence and the unknown fractions of the extractable organofluorine (EOF) not explained by commonly monitored target PFAS. In this study, eight pairs of raw and treated water were collected from drinking water treatment plants (DWTPs) around Taihu Lake in China and analyzed for EOF and 34 target PFAS. Mass balance analysis of organofluorine revealed that at least 68% of EOF could not be explained by target PFAS. Relatively higher total target concentrations were observed in 4 DWTPs (D1 to D4) when compared to other samples with the highest sum concentration up to 189 ng L-1. PFOA, PFOS and PFHxS were the abundant compounds. Suspect screening analysis identified 10 emerging PFAS (e.g., H-PFAAs, H-PFESAs and OBS) in addition to target PFAS in raw or treated water. The ratios PFBA/PFOA and PFBS/PFOS between previous and current studies showed significant replacements of short-chain to long-chain PFAS. The ratios of the measured PFAS concentrations to the guideline values showed that some of the treated drinking water exceeds guideline values, appealing for efforts on drinking water safety guarantee.
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| 3. |
- Jiao, Enmiao, et al.
(författare)
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Further Insight into Extractable (Organo)fluorine Mass Balance Analysis of Tap Water from Shanghai, China
- 2023
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Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 57:38, s. 14330-14339
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Tidskriftsartikel (refereegranskat)abstract
- The ubiquitous occurrence of per- and polyfluoroalkyl substances (PFAS) and the detection of unexplained extractable organofluorine (EOF) in drinking water have raised growing concerns. A recent study reported the detection of inorganic fluorinated anions in German river systems, and therefore, in some samples, EOF may include some inorganic fluorinated anions. Thus, it might be more appropriate to use the term "extractable fluorine (EF) analysis" instead of the term EOF analysis. In this study, tap water samples (n = 39) from Shanghai were collected to assess the levels of EF/EOF, 35 target PFAS, two inorganic fluorinated anions (tetrafluoroborate (BF4-) and hexafluorophosphate (PF6-)), and novel PFAS through suspect screening and potential oxidizable precursors through oxidative conversion. The results showed that ultra-short PFAS were the largest contributors to target PFAS, accounting for up to 97% of ΣPFAS. To the best of our knowledge, this was the first time that bis(trifluoromethanesulfonyl)imide (NTf2) was reported in drinking water from China, and p-perfluorous nonenoxybenzenesulfonate (OBS) was also identified through suspect screening. Small amounts of precursors that can be oxidatively converted to PFCAs were noted after oxidative conversion. EF mass balance analysis revealed that target PFAS could only explain less than 36% of EF. However, the amounts of unexplained extractable fluorine were greatly reduced when BF4- and PF6- were included. These compounds further explained more than 44% of the EF, indicating the role of inorganic fluorinated anions in the mass balance analysis.
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| 4. |
- Pan, Yitao, et al.
(författare)
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Novel Chlorinated Polyfluorinated Ether Sulfonates and Legacy Per-/Polyfluoroalkyl Substances : Placental Transfer and Relationship with Serum Albumin and Glomerular Filtration Rate
- 2017
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Ingår i: Environmental Science and Technology. - Dordrecht, Neteherlands : Springer Netherlands. - 0013-936X .- 1520-5851. ; 51:1, s. 634-644
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Tidskriftsartikel (refereegranskat)abstract
- Per- and polyfluoroalkyl substances (PFASs) may cross the placental barrier and lead to fetal exposure. However, little is known about the factors that influence maternal-fetal transfer of these chemicals. PFAS concentrations were analyzed in 100 paired samples of human maternal sera collected in each trimester and cord sera at delivery; these samples were collected in Wuhan, China, 2014. Linear regression was used to estimate associations of transfer efficiencies with factors. Chlorinated polyfluorinated ether sulfonates (Cl-PFAESs, 6:2 and 8:2) were frequently detected (>99%) in maternal and cord sera. A significant decline in PFAS levels during the three trimesters was observed. A U-shape trend for transfer efficiency with increasing chain length was observed for both carboxylates and sulfonates. Higher transfer efficiencies of PFASs were associated with advancing maternal age, higher education, and lower glomerular filtration rate (GFR). Cord serum albumin was a positive factors for higher transfer efficiency (increased 1.1-4.1% per 1g/L albumin), whereas maternal serum albumin tended to reduce transfer efficiency (decreased 2.4-4.3% per 1g/L albumin). Our results suggest that exposure to Cl-PFAESs may be widespread in China. The transfer efficiencies among different PFASs were structure-dependent. Physiological factors (e.g., GFR and serum albumin) were observed for the first time to play critical roles in PFAS placental transfer.
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