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Only a few dozens of the several thousand existing per- and polyfluoroalkyl substances (PFAS) are monitored using conventional target analysis. This study employed suspect screening to examine patterns of emerging and novel PFAS in German and Chinese river water affected by industrial point sources. In total, 86 PFAS were (tentatively) identified and grouped into 18 structure categories. Homologue patterns revealed distinct differences between fluoropolymer production sites of the two countries. In the Chinese Xiaoqing River Basin, the C 8 homologue was the most prevalent compound of the emerging series of chlorinated perfluoroalkyl carboxylic acids (Cl-PFCAs) and perfluoroalkylether carboxylic acids (PFECAs). In contrast, C 6 and shorter homologues were dominant in the German Alz River. This indicates that the phaseout of long-chain compounds in Europe and their ongoing production in Asian countries also apply to unregulated emerging PFAS classes. Additional characteristics to differentiate the point sources were the peak area ratio of perfluorobutane sulfonic acid (PFBS) versus the emerging compound hydro-substituted PFBS (H-PFBS) as well as the occurrence of byproducts of the sulfonated tetrafluoroethylene-based polymer Nafion. The large number of identified unregulated PFAS underlines the importance of a grouping approach on a regulatory level, whereas the revealed contamination patterns can be used to estimate, prioritize, and minimize contributions of specific sources.

Historical use of organochlorine pesticides (OCPs) in the Republic of Moldova could pose a potential risk for the aquatic environment due to the persistence, bioaccumulation and toxic properties of these environmental pollutants. However, knowledge on environmental concentrations of legacy OCPs in Moldova is limited. In this study, surface sediment from the two main rivers; Dniester (8 sites, n = 15) and Prut (6 sites, n = 12), and two tributary rivers; Bîc (11 sites, n = 11) and Răut (6 sites, n = 6), were collected during 2017-2018 and analyzed for hexachlorocyclohexanes (HCHs), dichlorodiphenyltrichloroethanes (DDTs) and their transformation products (DDDs and DDEs) using gas chromatography coupled to mass spectrometry (GC-MS/MS). Sediment concentrations of Ʃ 6 DDX (1.9-140 ng g -1 dry weight (dw)) and Ʃ 4 HCHs (n.d-2.5 ng g -1 dw) were found. In the big rivers, the average Ʃ 6 DDX concentration (18 ng g -1 dw) were 35 times higher than Ʃ 4 HCHs (0.51 ng g -1 dw). Whereas, in the small rivers the average Ʃ 6 DDX concentration (32 ng g -1 dw) was approximately 41 times higher than Ʃ 4 HCHs (0.77 ng g -1 dw). Compared to previous studies from Eastern Europe, the sediment levels were generally similar as found in Moldova's neighboring countries (Romania and Ukraine). Overall, the contamination profile indicates long-term ageing of OCPs used in the past in the agricultural sector. Less than half of the sites (45%) had levels that pose a potential risk for benthic organisms. Hence, further work is needed to determine the bioaccumulation of OCPs in the aquatic food web in this region and the associated risks to ecosystems and human health., (Copyright © 2021 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The spatial distribution of per- and polyfluoroalkyl compounds (PFCs) were investigated in coastal waters collected onboard research vessel Snow Dragon from the East to South China Sea in 2010. All samples were prepared by solid-phase extraction and analyzed using high performance liquid chromatography/negative electrospray ionization-tandem mass spectrometry (HPLC/(-)ESI-MS/MS). Concentrations of 9 PFCs, including C(4) and C(8) (PFBS, PFOS) perfluoroalkyl sulfonate (PFSAs), C(5)-C(9) and C(13) (PFPA, PFHxA, PFHpA, PFOA, PFNA, PFTriDA) perfluoroalkyl carboxylates (PFCAs), and N-ethyl perfluorooctane sulfonamide (EtFOSA) were quantified. The ΣPFC concentrations ranged from 133 pg/L to 3320 pg/L, with PFOA (37.5-1541 pg/L), PFBS (23.0-941 pg/L) and PFHpA (0-422 pg/L) as dominant compounds. Concentrations of PFCs were greater in coastal waters along Shanghai, Ningbo, Taizhou, Xiamen and along coastal cities of the Guangdong province compared to less populated areas along the east Chinese coast. Additionally, the comparison with other seawater PFC measurements showed lower levels in this study., (Copyright © 2011 Elsevier Ltd. All rights reserved.)