Soil contaminated with aqueous film-forming foams (AFFFs) containing per- and polyfluoroalkyl substances (PFASs) at firefighting training sites has become a major concern worldwide. To date, most studies have focused on assessing soil–water partitioning behavior of PFASs and the key factors that can affect their sorption, whereas PFASs leaching from contaminated soils have not yet been widely investigated. This study evaluated the leaching and desorption of a wide range of PFASs from twelve contaminated soils using the Australian Standard Leaching Procedure (ASLP), the U.S. EPA Multiple Extraction Procedure (MEP), and Leaching Environmental Assessment Framework (LEAF). All three leaching tests provided a similar assessment of PFAS leaching behavior. Leaching of PFASs from soils was related to C-chain lengths and their functional head groups. While short-chain (CF2 ≤ 6) PFASs were easily desorbed and leached, long-chain PFASs were more difficult to desorb. PFASs with a carboxylate head group were leached more readily and to a greater extent than those with a sulfonate or sulfonamide head group. Leaching of long-chain PFASs was pH-dependent where leaching increased at high pH, while leaching of short-chain PFASs was less sensitive to pH. Comparing different leaching tests showed that the results using the alkaline ASLP were similar to the cumulative MEP data and the former might be more practical for routine use than the MEP. No single soil property was adequately able to describe PFAS leaching from the soils. Overall, the PFAS chemical structure appeared to have a greater effect on PFAS leaching from soil than soil physicochemical properties.

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A model for predicting the time-dependent vertical thermal structure of lakes is presented. Radiative heating with depth, mixing induced by the surface wave field, and turbulent energy exchanges arc included as lake-averaged processes. The model was designed to be applicable to a wide range of lake sizes. Comparison of predictions with horizontally averaged observations from Lake Ontario during IFYGL and unaveraged (local) observations from Llyn Cwellyn, Wales, show good agreement.

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Contaminants of emerging concern (CECs) are ubiquitous throughout aquatic environments. Previous research has shown that CECs can have detrimental effects on fish biology, potentially leading to population impacts. Specifically, polybrominated diphenyl ethers (PBDEs), a class of CECs, have been shown to alter thyroid hormones in fish, which can impact development, endocrine system functioning, and possibly imprinting. These impacts can lead to reproductive effects and population declines, which have serious implications for species of conservation priority, such as the Lake Sturgeon Acipenser fulvescens. To assess the effects of CECs and PBDEs, Lake Sturgeon were evaluated at rearing facilities within the Great Lakes basin during 2017-2018 to determine (1) whether exposure to CECs and PBDEs differs between facility locations and (2) whether changes in whole-body PBDE concentrations correlate with changes in thyroid hormones (triiodothyronine [T 3 ] and thyroxine [T 4 ]), which could indicate impacts to imprinting. Exposure to CECs and PBDEs differed among sites. The CECs that were detected in water across all sites included atrazine, hexachlorobenzene, N,N-diethyl-meta-toluamide (DEET), desethylatrazine, erythromycin, and metformin, with the highest concentrations (except for DEET) measured at the Maumee River (Ohio) streamside rearing facility.We detected PBDEs in every sample of water, food, and Lake Sturgeon eggs and whole bodies, and there were no differences in lipid-normalized total PBDE concentrations in whole bodies across sites. Concentrations of total PBDE and the PBDE congeners 47, 99, 100, 153, 154, and 209 in fish tissues did not correlate with serum T 3 and T 4 levels, indicating that observed concentrations were unlikely to negatively impact Lake Sturgeon rearing for the biological endpoints assessed. Overall, this study exemplifies a cautionary tale since CECs and PBDEs were identified throughout Lake Sturgeon habitat and in hatchery food sources. Fisheries managers should be aware of the potential for CEC and PBDE impacts even though current observed levels do not seem to be impacting Lake Sturgeon rearing success.