Chlordecone (CLD), an organochlorine insecticide, and other persistent organic pollutants continue to contaminate the environment worldwide and have adverse effects on human health through food exposure. Cucurbitaceae take up weathered hydrophobic pollutants from the soil and translocate them to their shoots. As Cucurbitaceae are an important part of the diet in the French West Indies, they are among the main contributors to total dietary intake of CLD. We analyzed the contamination by CLDs (CLD and 5b-hydroCLD) of four cucurbits grown in the field and/or in the greenhouse. Different physiological (crop species) and environmental (soil type, growth conditions) variables were shown to influence uptake of the pollutant from the soil by the crop. Cucurbita species (zucchini and pumpkin) were more contaminated than Cucumis sativus (cucumber), and Sechium edule (christophine or chayote) translocated CLDs to fruits very poorly compared with cucumber and pumpkin. Greenhouse conditions and non-allophanic (nitisols and ferralsols) soils favored plant contamination more than field conditions and allophanic soils (andosols). (Résumé d'auteur)

Currently, the geological storage of CO2 is heavily studied around the world in order to limit global warming due to the greenhouse effect. The atmospheric CO2, which has been steadily increasing for more than a century, is assumed to be in a large part responsible of this warming. Nowadays, various options have been considering to store CO2 in an underground environment for periods covering several centuries. Among the options, one is to inject it in unexploited coal seams. The objective of our work is to characterise the interactions between CO2 ans coal interfaces from two French coal seams. This will contribute to identify the most adapted coal basin which could be used for storing CO2 in France.

Currently, the geological storage of CO2 is heavily studied around the world in order to limit global warming due to the greenhouse effect. The atmospheric CO2, which has been steadily increasing for more than a century, is assumed to be in a large part responsible of this warming. Nowadays, various options have been considering to store CO2 in an underground environment for periods covering several centuries. Among the options, one is to inject it in unexploited coal seams. The objective of our work is to characterise the interactions between CO2 ans coal interfaces from two French coal seams. This will contribute to identify the most adapted coal basin which could be used for storing CO2 in France.

Dissolved organic matter (DOM) plays a significant role in the photochemical behavior of nano- and micro-plastic particles (NPs/MPs). We investigated the influence of DOM on the mechanism on the photoaging of NPs/MPs with different molecular structures under UV₃₆₅ irradiation in water. DOM components used in this study are mainly humic acid and fulvic acid. The results showed that DOM promoted the weathering of aliphatic NPs/MPs (polypropylene (PP)), but inhibited or had only a minor effect on the photoaging of aromatic NPs/MPs (polystyrene (PS) NPs/MPs, carboxyl-modified PS NPs, amino-modified PS NPs, and polycarbonate MPs). NPs with a large surface area may adsorb sufficient DOM on the particle surfaces through π-π interactions, which competes with NPs for photon absorption sites, thus, can delay the photoaging of PS NPs. Aromatic MPs may release phenolic compounds that quench •OH, thereby weakening the photoaging process. For aliphatic MPs, the detection of peracid, aldehyde, and ketone groups on the polymer surface indicated that DOM promoted weathering of PP MPs, which was primarily because the generation of •OH due to DOM photolysis may attack the polymer by C–C bond cleavage and hydrogen extraction reactions. This study provides insight into the UV irradiation weathering process of NPs/MPs of various compositions and structures, which are globally distributed in water.

Currently little is known about the adsorption behaviors of metalloids on microplastics (MPs) and their complex toxic effects on aquatic plants. Herein, we investigated the adsorption behaviors of arsenic (As(III) and As(V)) on three types of MPs (polystyrene, polyvinyl chloride, and polyethylene) with four different particle sizes (100, 10, 1, and 0.1 μm). Compared with the short-term exposure experiment, co-toxicity of polystyrene nanoplastics (PS-NPs) and As on two submerged macrophytes (Vallisneria denseserrulata and Potamogeton crispus) were explored through two relatively longer 14-day-cultivation experiments in summer and spring, respectively. The adsorption results showed that As entered the internal surface adsorption site of MPs at 24 h and fully combined to reach equilibrium. The adsorption capacity also enhanced with the increase of MPs concentrations, which generated more adsorption sites for binding with MPs. The presence of PS-NPs increased the absorption of As on macrophytes by 36.2–47.2%. More serious damage of leaf structure by combined PS-NPs and As was observed by transmission electron microscope. The larger harms by the co-toxicity of MPs and As were also reflected by the changes in physiochemical characteristics (e.g. photosynthesis) and the enhancement of oxidative damage of macrophytes. This work provides a clear theoretical basis for the behavior of PS-NPs as carrier with other contaminants on submerged macrophytes, and clearly evaluates the co-toxicity of NPs and metalloids in complex aquatic environments.

In this work, we report a facile receptor OMB [N′,N”’-(3-((4-oxochroman-3-yl)methylene)pentane-2,4- diylidene)bis(4-methoxybenzohydrazide)] for the simultaneous detection of toxic analytes (Hg²⁺ and Cd²⁺ ions) in environment and biological samples. The receptor OMB exhibits an excellent selectivity and sensitivity which was determined using absorption and emission spectra. The receptor OMB shows rapid detection with lowest LOD (0.62 nM for Hg²⁺ ions and 0.77 nM for Cd²⁺ ions) and LOQ (2.08 nM for Hg²⁺ ions and 2.57 nM for Cd²⁺ ions) values. In addition, the receptor OMB exhibits 1:1 binding stoichiometry towards Hg²⁺ and Cd²⁺ ions with binding constant values of 5.5 × 10⁶ M⁻¹ and 4.6 × 10⁶ M⁻¹. Moreover, the synthesized receptor OMB possess ability to detect these analytes (Hg²⁺ and Cd²⁺ ions) in realistic samples (food and water) which was recognized using photoluminescence spectroscopy technique. In addition, the receptor OMB is also utilized to detect both the analytes in live HeLa cells. Thus, the overall results indicate that the receptor OMB was more suitable to detect the toxic analytes (Hg²⁺ and Cd²⁺ ions) present in the environment.

Nanoplastic is recognized as an emerging environmental pollutant due to the anticipated ubiquitous distribution, increasing concentration in the ocean, and potential adverse health effects. While our understanding of the ecological impacts of nanoplastics is still limited, we benefit from relatively rich toxicological studies on other nanoparticles such as nano metal oxides. However, the similarity and difference in the toxicokinetic and toxicodynamic aspects of plastic and metallic nanoparticles remain largely unknown. In this study, juvenile Pacific white shrimp Litopenaeus vannamei was exposed to two types of nanoparticles at environmentally relative low and high concentrations, i.e., 100 nm polystyrene nanoplastics (nano-PS) and titanium dioxide nanoparticles (nano-TiO₂) via dietary exposure for 28 days. The systematic toxicological evaluation aimed to quantitatively compare the accumulation, excretion, and toxic effects of nano-PS and nano-TiO₂. Our results demonstrated that both nanoparticles were ingested by L. vannamei with lower egestion of nano-TiO₂ than nano-PS. Both nanoparticles inhibited the growth of shrimps, damaged tissue structures of the intestine and hepatopancreas, disrupted expression of immune-related genes, and induced intestinal microbiota dysbiosis. Nano-PS exposure caused proliferative cells in the intestinal tissue, and the disturbance to the intestinal microbes was also more serious than that of nano-TiO₂. The results indicated that the effect of nano-PS on the intestinal tissue of L. vannamei was more severe than that of nano-TiO₂ with the same particle size. The study provides new theoretical basis of the similarity and differences of their toxicity, and highlights the current lack of knowledge on various aspects of absorption, distribution, metabolism, and excretion (ADME) pathways of nanoplastics.

Aquatic natural colloids are closely related to the environmental behavior of pollutants, which may affect their bioavailability in aquatic organisms. This study explored the potential mechanisms of the natural colloids at environmentally relevant concentrations affecting the bioaccumulation process of benzophenone-3 (BP3) in zebrafish (Danio rerio). The results of kinetic model fitting showed that the natural colloids decreased the uptake and loss rate of BP3 by zebrafish but prolonged the time to reach the cumulative equilibrium, eventually resulting in a higher cumulative concentration in zebrafish. According to the tissue concentration at equilibrium and the results of toxicokinetic analysis, the presence of high molecular colloids could enhance the bioaccumulation of freely dissolved BP3 due to its high desorption rate with BP3 in the intestines of fish, increasing the freely dissolved BP3 concentrations to which zebrafish were exposed. Both natural colloids and BP3 could enhance the cell permeability of zebrafish, which allowed colloid-bound BP3 to directly enter the fish and accumulate in its muscle. Besides, although both natural colloids and BP3 could cause the metabolic disorders in adult zebrafish, they affected the physiological and biochemical activities of zebrafish through different pathways. The disturbance of glutathione metabolism in zebrafish induced by natural colloids may be the reason for the diminished ability of zebrafish to clear and transform BP3 in the mixture system. The carrier effect of natural colloids and reduced clearance ability of zebrafish eventually increased the bioaccumulation of BP3 in zebrafish. This study highlights the significance of natural colloids at environmentally relevant concentrations on the biological effects of emerging contaminants in actual waters, however, natural colloids are always ignored in most field investigation of pollutants, which would ultimately lead to an underestimation of the true ecological risk of pollutants.