Dominique Grandjean | EPFL Graph Search

À propos de ce résultat

Cette page est générée automatiquement et peut contenir des informations qui ne sont pas correctes, complètes, à jour ou pertinentes par rapport à votre recherche. Il en va de même pour toutes les autres pages de ce site. Veillez à vérifier les informations auprès des sources officielles de l'EPFL.

Adsorption of progesterone onto microplastics and its desorption in fish following digestion with simulated gastric and intestinal fluids

Florian Frédéric Vincent Breider, Dominique Grandjean, Yang Liu, Thibault Béranger Masset, Cécilia Laetitia Carla Siri

The sorption of hydrophobic organic compounds onto microplastics is relatively well reported in the literature, while their desorption remains poorly investigated, especially in biological fluids. The present study investigated the sorption and desorption of progesterone on polyethylene (PE), polypropylene (PP), and polystyrene (PS) microplastics. A sorption efficiency of 357.1 mg g-1 was found for PE and PS, and 322.6mg g-1 for PP. Sorption experiments indicated that adsorption would certainly happen via surface sorption and a potentially pore-filling mechanism. The desorption was carried out in Simulated Gastric Fluid (SGF) and Simulated Intestinal Fluid (SIF). It has been found that the desorption was higher in SIF as compared to SGF, due to micelle formation in SIF promoting the pollutant solubilization. This study indicates that the ingestion of microplastics could be considered as an additional route of exposure to pollutants and therefore emphasizes pollutant bioavailability for aquatic organisms.

2022

Associations between urinary biomarkers of oxidative stress and biomarkers of tobacco smoke exposure in smokers

Florian Frédéric Vincent Breider, Dominique Grandjean, Nicolas Sambiagio

Oxidative stress can contribute to the development of diseases, and may originate from exposures to toxicants commonly found in air pollution and cigarette smoke such as polycyclic aromatic hydrocarbons (PAHs) and volatile organic compounds (VOCs). Yet, associations between these exposures and oxidative stress biomarkers are poorly characterized. We report here novel associations between 14 exposure biomarkers of PAHs and VOCs, and two oxidative stress biomarkers; 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG) and 8-isoprostaglandin F2α (8-isoprostane) in urine obtained from smokers participating in an ongoing clinical study (ESTxENDS, NCT03589989). We also assessed associations between six biomarkers of tobacco smoke exposure (metabolites of nicotine and tobacco-specific nitrosamines (TSNAs)) and both oxidative stress biomarkers. We then quantified the relative importance of each family of the 20 exposure biomarkers on oxidative stress. Participating smokers (153 men and 117 women, median age 44 years) had on average smoked 25 [2–62] years and smoked about 17 [5–40] cigarettes per day at the time of the study. Multiple linear regression results showed an association between 8-oxodG concentrations and the following metabolites in decreasing relative importance: PAHs (beta coefficient β = 0.105, p-value VOCs (β = 0.028, p < 0.001, partial R² = 0.09) > nicotine (β = 0.226, p < 0.001, partial R² = 0.08); and between 8-isoprostane concentrations and metabolites of PAHs (β = 0.117, p < 0.001, partial R² = 0.14) > VOCs (β = 0.040, p < 0.001, partial R² = 0.14) > TSNAs (β = 0.202, p = 0.003, partial R² = 0.09) > nicotine (β = 0.266, p < 0.001, partial R² = 0.08). Behavioral factors known to contribute to oxidative stress, including sleep quality, physical activity, and alcohol consumption, did not play a significant role. Exposures to PAHs and VOCs among smokers were significantly associated with oxidative stress.

Elsevier2022

Bioaccessibility of organic compounds associated with tire particles using a fish in vitro digestive model: solubilization kinetics and effects of food co-ingestion

Florian Frédéric Vincent Breider, Benoît Jean Dominique Ferrari, Dominique Grandjean, Luke Christopher Harris, Thibault Béranger Masset, Kristin Schirmer

Tire and road wear particles (TRWP) account for an important part of the polymer particles released into the environment. There are scientific knowledge gaps as to the potential bioaccessibility of chemicals associated with TRWP to aquatic organisms. This study investigated the solubilization and bioaccessibility of seven of the most widely used tire-associated organic chemicals and four of their degradation products from cryogenically milled tire tread (CMTT) into fish digestive fluids using an in vitro digestion model based on Oncorhynchus mykiss. Our results showed that 0.06% to 44.1% of the selected compounds were rapidly solubilized into simulated gastric and intestinal fluids within a typical gut transit time for fish (3 h in gastric and 24 h in intestinal fluids). The environmentally realistic scenario of coingestion of CMTT and fish prey was explored using ground Gammarus pulex. Coingestion caused compound-specific changes in solubilization, either increasing or decreasing the compounds’ bioaccessibility in simulated gut fluids compared to CMTT alone. Our results emphasize that tire-associated compounds become accessible in a digestive milieu and should be studied further with respect to their bioaccumulation and toxicological effects upon passage of intestinal epithelial cells.

2022