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Perfluoroalkyl substances (PFASs) have become an important class of global environmental contaminants, yet their vertical profile in the marine water column is still less understood, especially for the semi-closed seas. In this study, the contamination level and spatial distribution of 8 PFASs were investigated in both surface and vertical water samples from two semi-closed seas, the Japan Sea and the Mediterranean Sea. Similar levels and compositions of PFASs were found between these two seas. The vertical profile of PFASs in the Mediterranean Sea was variable while that was relatively steady in the Japan Sea, probably due to their different pollution sources. The accumulation rate of PFASs from the East China Sea to the Japan Sea was calculated, for which perfluorooctanesulfonic acid and perfluorooctanoic acid were found to have high accumulation potency in both surface and deep water; most of the investigated PFASs were accumulated in the deep water due to the long residence time while they were more likely to escape to the Pacific Ocean in the surface water. This work aimed (i) to study the distribution of PFASs in both surface and vertical water samples in two semi-closed seas, namely the Japan Sea and for the first time the Mediterranean Sea, (ii) to assess the temporal trend in the Japan Sea, and (iii) to firstly investigate the potential transport of PFASs from the East China Sea and Taiwan Strait in order to estimate the inventory of PFASs in whole water mass in the Japan Sea. Image 1 • A remarkable increase in PFASs levels was found in the Japan Sea from 2005 to 2010. • The inventory of PFASs in whole water mass was firstly assessed in semi-closed sea. • The annual ΣPFASs inflow from the East China Sea to the Japan Sea was around 70.8 t. • The PFASs vertical profile in the Mediterranean Sea implied a few pollution sources. • PFOA predominated in the Japan Sea, the Mediterranean Sea, and the East China Sea. [ABSTRACT FROM AUTHOR]

Perfluoroalkyl substances (PFASs) are a group of contaminants of concern in agricultural crops, but little is known of their accumulation or behavior in grains. We grew Japanese rice (Oryza sativa subsp. indica) in lysimeters irrigated with tap water or tap water plus simulated contaminated water for 2 years, then analyzed the roots, straw, unhulled rice, white rice, bran, soil, and water for PFASs residues. Total fluorine was measured by combustion ion chromatography. Estimated per-plant residue levels were 3.0 pg perfluorooctanesulfonic acid (PFOS) (bran: 0.5%, hull: 99.5%), 0.54 pg N -ethylperfluorooctanesulfonamide (N -EtFOSA) (white rice: 67%, hull: 33%), 1.2 pg perfluorobutanoic acid (PFBA) (white rice: 13%, bran: 7%, hull: 79%), 0.68 pg perfluoropentanoic acid (hull: 100%), 0.50 pg perfluorohexanoic acid (PFHxA) (white rice: 65%, bran: 16%, hull: 19%), 0.21 pg perfluoroheptanoic acid (hull: 100%), 0.25 pg perfluorooctanoic acid (PFOA) (hull: 100%), and 0.12 pg perfluorodecanoic acid (PFNA) (white rice: 81%, bran: 19%). Estimated daily PFASs intakes were <1–3 ng perfluorooctanesulfonamide, <1–7 ng N-EtFOSA, 1–2 ng PFBA, <3–4 ng PFHxA, and 1–2 ng PFNA. Estimated PFOS, PFOA, and total PFASs in straw feed were 0.4, 0.1, and 2 kg yr−1 and 0.7, 0.4, and 8 kg yr−1 in 2015 and 2016, respectively. Estimated PFOS, PFOA, and total PFASs in straw fertilizer were 4, 1, and 23 kg yr−1 and 7, 4, and 86 kg yr−1 in 2015 and 2016, respectively. PFASs accumulation may cause longer residence time in agricultural systems owing to straw being used as animal feed and organic fertilizer. Image 1 • Lysimeter-grown rice was irrigated with tap water alone or added contamination. • PFASs were analyzed for rice plant. • PFOS and PFOA were not detected in white rice. • PFASs were accumulated in unhulled rice, rice bran, straw and roots. • FOSA had the highest transfer factor from soil to rice, similar to N and P. [ABSTRACT FROM AUTHOR]

In the atmosphere, the photodegradation of neutral per-and polyfluoroalkyl substances (n-PFASs) is a source of ionizable PFASs (i-PFASs). However, they are not frequently simultaneously analyzed to study their transport and sources. In this study, n-PFASs and i-PFASs were simultaneously analyzed in the atmosphere of China, Japan and Malaysia to investigate the occurrence, seasonal variations, sources and transport. Results showed that n-PFASs ranged from 4.8 to 1400 pg m -3 , with an average value of 170 pg m -3 , and 8:2 fluorotelomer alcohol (8:2 FTOH) was the most abundant compound. i-PFASs ranged from 3.7 to 330 pg m -3 , with an average value of 49 pg m -3 , and perfluorobutanoic acid (PFBA) had the highest concentration. Generally, airborne PFASs had a decreasing gradient from cities with high population density toward less industrialized sites. i-PFASs exhibited significantly (P < 0.05) seasonal variations, which were higher in the summer. 8:2 FTOH and 10:2 FTOH had significant (P < 0.05) positive correlations with perfluorooctanoic acid and perfluorodecanoic acid, suggesting that they had same sources, such as co-emission and photodegradation of FTOHs. Urumqi and Selangor were far away from industry, and high percentages (>95%) but low concentrations of PFBA were found in these cities, indicating the long-range atmospheric transport of PFBA due to its high volatility. The Summer Monsoon may promote the transport of high concentrations of PFAS from coastal cities to inland cities., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Information regarding the size-dependent distribution of per- and polyfluoroalkyl substances (PFAS) in atmospheric particulate matter (PM) is very limited. In this study, 248 size-specific PM samples were collected from 9 Asian cities using a portable 4-stage cascade impactor for the analysis of PFAS. Of the 34 investigated PFAS, perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) were the major compounds. In particular, the emerging PFAS, hexafluoropropylene oxide dimer acid, was quantified in the PM for the first time, with concentrations ranging from <0.086 to 21.5 pg/m 3 . Spatially, PFOA and PFOS were the predominant compounds in China, while precursors, emerging PFAS, and short-chain PFAS dominated in India, Japan, and South Korea, respectively. Seasonal variations of PFAS may be controlled by regional climate, local or seasonal emission sources, and long-range transport of air masses. Size-dependent distribution was investigated, showing that the majority of PFAS predominantly affiliated in fine particles, while PFOS and its alternatives tended to attach on coarser particles. Moreover, PFOS distributed on specific sizes exhibited seasonal and regional dependency, while no such patterns were observed for PFOA. These findings will provide useful information on the geographical and size-dependent distribution of PFAS in the atmospheric PM.