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The characteristics of regional environmental pollution of short- and medium-chain chlorinated paraffins (SCCPs and MCCPs) in river system from Shanghai were comprehensively investigated in this study for the first time. The total concentrations of SCCPs and MCCPs ranged from 15.0 to 1640 ng L−1 (median: 278 ng L−1) and 40.3 to 3870 ng L−1 (median: 939 ng L−1) in water, and from not detected (ND) to 2020 ng g−1 (median: 89.3 ng g−1) and 10.1 to 10,800 ng g−1 (median: 947 ng g−1) in sediments, respectively. The higher levels of SCCPs and MCCPs were found in water from Jinhui and Yexie rivers, and in sediments from Huangpu River, respectively. The concentrations of MCCPs were higher than those of SCCPs in both water and sediments, suggesting that the river system was mainly contaminated by MCCPs. Compared with other areas around the world, the concentrations of SCCPs and MCCPs were at medium to high levels in water and sediments. Factor analysis results revealed that SCCPs and MCCPs had different sources in both water and sediments. The log Koc values of CPs were significantly correlated with carbon chain lengths (p 0.05). A significant second-order polynomial relationship was observed between log Koc values and molecular weights of homologue groups of SCCPs (p

Perfluoroalkyl acids (PFAAs) are persistent environmental pollutants that have been detected in various media including human serum. Due to concerns regarding their bioaccumulation and possible negative health effects, an understanding of routes of human exposure is necessary. PFAAs are recalcitrant in many water treatment processes, making drinking water a potential source of human exposure. This study presents the first report on contamination from PFAAs in river and drinking water in Ghana. The targeted PFAAs were perfluoroalkyl carboxylic acids (PFCAs) with C4–14 carbon chain and perfluoroalkane sulphonic acids (PFSAs) with C6, 8, 10. Five PFAA congeners – PFOA, PFOS, PFHxA, PFDA and PFPeA – were commonly detected in river and tap water. The mean concentrations of ∑ PFAAs in the Kakum and Pra Rivers were 281 and 398 ng/L, while tap water (supplied from the treatment of water from those rivers) contained concentrations of 197 and 200 ng/L, respectively. PFOA and PFOS constituted about 99% of the ∑ PFAAs. The risk quotient (RQ) attributed to drinking of tap water was estimated at 1.01 and 1.74 for PFOA and PFOS, respectively. For a country that has not produced these compounds, the RQs were unexpectedly high, raising concerns particularly about contamination from such emerging pollutants in local water sources. The study revealed limitations of local tap water treatment in getting rid of these emerging pollutants.

In this study, 17 legacy and emerging PFASs were investigated in soil and plant leaves near a valley-type landfill, which has been in operation for over 20 years. ΣPFASs concentrations ranged from 5.31 to 108 ng/g dw and 11.9 to 115 ng/g dw in the soil and leaf samples, respectively, and perfluorobutanoic acid (PFBA) was dominant in both soil and leaves. The concentrations of hexafluoropropylene oxide dimer acid (HFPO-DA), 6:2 chlorinated polyfluorinated ether sulfonic acid (F-53B) and 6:2 fluorotelomer sulfonic acid (6:2 FTS) were significantly higher than those of legacy PFOA and PFOS, indicating emerging alternatives were widely applied in the region. The integrated approach of PCA analysis, field investigation of relevant industrial activities in the study area, along with the Unmix model analysis quantitatively revealed that factories producing consumer products and the landfill were the major sources of PFASs in soil, accounting for 57% of total PFASs detected. Bioaccumulation factors (BAFs) of ΣPFASs in leaves varied from 0.37 to 8.59, and higher BAFs were found in camphor leaves. The log10BAFs in all plant leaves showed a linear decrease with increasing carbon chain lengths for individual PFCAs (C4–C8). The BAF values of HFPO-DA, F-53B and 6:2 FTS were 0.01–3.39, 0.04–6.15 and 0.01–6.33, respectively. The human health risk assessment of EDIs showed a decreasing trend with the increasing carbon chain lengths of PFCAs (C4–C9), and the PFASs EDI indicated further study on the human health risk via vegetable consumption be warranted.

Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are contaminants of great concern due to their wide-spread occurrence and persistence in the environments (i.e., in water, soil and sediment) and potential toxicology even at very low concentration. The main focus of this review is on the PFASs in soil and sediments. More specifically, this review systematically examines the occurrence and toxicological effects with associated risks, fate (i.e., PFASs adsorption by soil and sediment, transportation and transformation, and bioaccumulation), and remediation practices of PFASs in soil and sediment. Various models and equations such as fugacity-based multimedia fate and hydrodynamic models are used to study the fate, transport, and transformation of PFASs. Among different remediation practices, sorption is the dominant process for the removal of PFASs from soil and sediments. Results also indicate that PFASs adsorption onto activated carbon decrease with the increase of carbon chain length in the PFASs. The longer-chain PFASs have larger partition coefficient values than shorter-chained PFASs. Sorption of PFASs to soil and sediments are mainly governed by different electrostatic interactions, hydrogen bonds formation, hydrophobic interactions, organic content in soil and sediments, and ligand exchange. Other technology such as thermal treatment might be potential in the removal of PAFSs, but need further study to elucidate a conclusion. Finally, the associated challenges and future outlook have been included.

The uptake rates of three perfluorinated carboxylates and three perfluorinated sufonates by a grass (B diandrus) grown in nutrient solution at two different perfluorinated compounds (PFCs) concentrations were assessed. Grass can be ingested by grazing animals causing the PFCs to enter the food chain, which is a pathway of human exposure to these compounds. A rapid and miniaturized method was developed to determine PFCs in plants, based on a matrix solid-phase dispersion (MSPD) extraction procedure followed by quantitation by HPLC-MS/MS with an MQL in the range from 1 to 9. ng/g. An increase of PFCs levels in plant was observed along the exposure time. Differences in uptake for studied perfluorinated carboxylates were found, showing a decrease with carbon chain length (from 3027 to 1167. ng/g at the end of assay), whereas no significant differences in absorption were obtained between perfluorinated sulfonates (about 1700. ng/g). Initially, higher PFC transfer factors (ratio between concentration in plant and concentration in initial nutrient solution) were obtained for plants growing in the nutrient solution at the highest PFC concentration, but these factors became similar with time to plants exposed to the lowest concentration. © 2013 Elsevier B.V.

Perfluoroalkyl substances (PFASs) are ubiquitous in the environment world-wide. Our overall objective was to assess the exposure to PFASs experienced by delivering women and their new-borns in the industrial city of Norilsk (arctic Russia) and the rural Aral Sea region of Uzbekistan, with the secondary objective of evaluating the distribution of PFASs between blood cell and plasma fractions. Six PFASs were detected in every sample from Norilsk city with the plasma concentration sequence of: PFOS≫PFOA>PFNA>FOSA>PFHxS>PFUnDA. In the Uzbekistani samples, only PFOS was reported above the MDL (0.08 ng/mL). The median plasma concentrations of PFOS of 11.0 ng/mL for the Norilsk mothers was comparable to that reported for western countries, while that for Uzbekistan was considerably lower (0.23 ng/mL). Apparent increases in the maternal-cord concentration ratios for both whole blood and plasma were evident with the length of the carbon chain for both the carboxylate and the sulfonate PFASs. The median value of this ratio for FOSA in plasma was the lowest, while that for whole blood was the highest. Other than for FOSA, the observed plasma-whole blood concentration ratios for maternal and umbilical cord blood were consistent with a priori calculations using appropriate packed cell and plasma volumes for neonates and pregnant women at term. Clearly FOSA favored whole blood, and acid-base equilibrium calculations suggested that the resonance-stabilized sulfonamidate ion resides in the blood cell fraction. Thus for PFASs and related compounds with pK values with magnitudes comparable to physiological pH, it is pertinent to measure the cell-associated fraction (separately or as whole blood). Our study illustrates that consideration of both the physico-chemical properties of the contaminants and the physiological attributes of blood matrices were helpful in the interpretation of our findings.