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2012
1999
Leaching of chemicals and DOC from tire particles under simulated marine conditions
Tire wear particles (TWPs) represent one of the major anthropogenic pools of particles ending up in the environment. They contain a large variety of chemicals, a part of which may be released into the environment through leaching, although the influence of sunlight and other environmental factors during this process is still unclear. This laboratory study compares the leaching of organic compounds from TWP in seawater in the dark and under artificial sunlight for 1) cryo-milled tire tread (CMTT), 2) ‘virgin’ crumb rubber (VCR) and 3) crumb rubber immersed in the sea for ≥12 months prior to the experiments (WCR). Leachates were analyzed for dissolved organic carbon (DOC) and 19 tire-derived chemicals, benzothiazoles and phenylguanidines as well as phenylendiamines by liquid chromatography-high resolution-mass spectrometry. For DOC and most chemicals, the amounts released decreased in the order CMTT > VCR > WCR and increased when leaching occurred under artificial sunlight. sunlight also led to the formation of 23 transformation processes related to 1,3-diphenylguanidine (DPG). In contrast, 4-hydroxydiphenylamine (4-HDPA) and N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine quinone (6-PPDQ) were found in lower amounts upon sunlight exposure. The 19 quantified chemicals, however, did only account for 6%–55% of the DOC in the leachates; most of the DOC, thus, remained unexplained. This study highlights that the amount of chemicals leached from tire particles depends upon their aging history and may be modulated by environmental conditions.
Frontiers Media S.A.
2023
2023
American Geophysical Union (AGU)
2019
2018
2017
2020
More than 70 years of industrial production of per- and polyfluoroalkyl substances (PFAS) have resulted in their ubiquitous presence in the environment on a global scale, although differences in sources, transport and fate lead to variability of occurrence in the environment. Gull eggs are excellent bioindicators of environmental pollution, especially for persistent organic pollutants such as PFAS, known to bioaccumulate in organisms and to be deposited in bird eggs by maternal transfer. Using yellow-legged gull (Larus michahellis) eggs, we investigated the occurrence of more than 30 PFAS, including the most common chemicals (i.e., legacy PFAS) as well as their alternatives (i.e., emerging PFAS) in the Bay of Marseille, the second largest city in France. Compared to eggs from other colonies along the Mediterranean coast, those from Marseille had PFAS concentrations ranging from slightly higher to up to four times lower, suggesting that this area cannot be specifically identified as a hotspot for these compounds. We also found several emerging PFAS including 8:2 and 10:2 FTS, 7:3 FTCA or PFECHS in all collected eggs. Although the scarcity in toxicity thresholds for seabirds, especially during embryogenesis, does not enable any precise statement about the risks faced by this population, this study contributes to the effort in documenting legacy PFAS contamination on Mediterranean coasts while providing valuable novel inputs on PFAS of emerging concern. Identifying exposure in free-ranging species also participate to determine the main target for toxicity testing in wildlife.
Elsevier
2025
Legacy perfluoroalkyl acids and their oxidizable precursors in plasma samples of Norwegian women
Humans are exposed to perfluoroalkyl acids (PFAA) mainly through direct pathways, such as diet and drinking water, but indirect exposure also occurs when PFAA precursors break down to form legacy PFAA. Exposure to PFAA precursors raises particular concern, as neither the exposure nor the precursors themselves have been well described. In the present study, we aimed to assess the indirect contribution of oxidizable PFAA precursors to the total per- and polyfluoroalkyl substances (PFAS) burden in human plasma following the voluntary phase-out of production of long-chain PFAS. In addition, multiple logistic regression was used to explore associations between selected lifestyle and dietary factors and the oxidizable PFAA precursors fraction. This study included 302 cancer-free participants of the Norwegian Women and Cancer postgenome cohort. PFAS analyses were performed in plasma samples to determine PFAS concentrations before and after oxidation with the Total Oxidizable Precursor (TOP) assay. In pre-TOP analyses, perfluorooctane sulfonic acid (PFOS) was the dominant compound, followed by perfluorooctanoic acid (PFOA).The vast majority (98%) of the study population had increased post-TOP concentrations for at least one PFAA. The formation of PFAA accounted for 12% of the total PFAS burden, with seven PFAA observed post-TOP in at least 30% of study participants. PFHpA, br- PFOA, and PFDA were only detected in post-TOP analyses and showed the highest increase in concentrations. Of the PFAA with increased concentrations, we noted significant associations for year of birth, parity, BMI, and some dietary factors, although they were not consistent between the different PFAA. These results indicate that while the TOP assay might not provide a complete assessment of total PFAS burden in humans, it offers comprehensive assessment of unknown PFAA precursors that might be present in plasma, and it could therefore be implemented as an auxiliary tool in this regard.
Elsevier
2023
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