This study assessed the environmental risk on coastal ecosystems posed by three phenolic compounds of special environmental and human health concern used in plastics and household products: bisphenol A (BPA), triclosan (TCS) and 4-nonylphenol (4-NP). These three chemicals are among the organic contaminants most frequently detected in wastewater. The most toxic compound tested was 4-NP, with 10% effective concentration at 11.1 μg L⁻¹ for Isochrysis galbana, 110.5 μg L⁻¹ for Mytilus galloprovincialis, 53.8 μg L⁻¹ for Paracentrotus lividus, and 29.0 μg L⁻¹ for Acartia clausi, followed by TCS (14.6 μg L⁻¹ for I. galbana, 149.8 μg L⁻¹ for M. galloprovincialis, 129.9 μg L⁻¹ for P. lividus, and 64.8 μg L⁻¹ for A. clausi). For all species tested, BPA was the less toxic chemical, with toxicity thresholds ranging between 400 and 1200 μg L⁻¹ except for A. clausi nauplii (186 μg L⁻¹). The relatively narrow range of variation in toxicity considering the broad physiological differences among the biological models used point at non-selective mechanisms of toxicity for these aromatic organics. Microalgae, the main primary producers in pelagic ecosystems, showed particularly high susceptibility to the chemicals tested. When the toxicity thresholds experimentally obtained were compared to the maximum environmental concentrations reported in coastal waters, the risk quotients obtained correspond to very low or low risk for BPA and TCS, and from low to high for 4-NP.

The use of reclaimed wastewater for irrigation is foreseen as a possible strategy to mitigate the pressure on water resources in dry regions. However, there is the risk of potential accumulation of contaminants of emerging concern (CECs) in the edaphic environment, their percolation and consequently contamination of aquifers. In the present study, we measured the levels of a wide range of commonly used pharmaceutically active compounds (PhACs) in sewage from a local wastewater treatment plant (WWTP) and in soils irrigated with treated wastewater. Analysis of target compounds showed total concentrations between 73 and 372 μg L⁻¹ in WWTP influents, and from 3 to 41 μg L⁻¹ in effluents. The total concentrations of PhACs detected in surface soil samples were in the range of 2 and 15 ng g⁻¹, with predominance of analgesics and anti-inflammatories (maximum concentration = 10.05 ng g⁻¹), followed by antibiotics and psychiatric drugs (maximum concentration = 5.45 ng g⁻¹ and 3.78 ng g⁻¹, respectively). Both effluent samples and irrigated soils shared similar compositional patterns, with compounds such as hydrochlorothiazide and diclofenac being predominant. Additionally, PhACs were also detected in soil samples at a depth of 150 cm, indicating that these chemical undergo leaching associated with heavy-rain episodes. Their occurrence in soils was affected by temperature too, as maximum concentrations were measured in colder months (up to 14 ng g⁻¹), indicating higher persistence at lower temperatures. Finally, the ecotoxicological risk of PhACs in soil was evaluated by calculating their risk quotients (RQs). The risk was very low as RQ values ranged between <0.01 and 0.07. However, this initial assessment could be improved by future works on toxicity using specific terrestrial organisms.

The objective of this study is to investigate the qualitative contribution of internal and external factors of the area contaminated by polystyrene (PS) in coastal marine environments. This study is based on the extensive results of monitoring the styrene oligomers (SOs) present in sand and seawater samples along various coastlines of the Pacific Ocean. Here, anthropogenic SOs is derived from PS during manufacture and use, and can provide clues about the origin of SOs by PS pollution. The monitoring results showed that, if the concentration of SOs in water is higher than those concentrations in beach sand, this area could be affected by PS plastic caused by an external factor. On the other hand, if the concentration of SOs is higher in the beach sand, the region can be mainly influenced by PS plastic derived from its own area. Unlike the case of an external factor, in this case (internal influence), it is possible to take policy measures of the area itself for the PS plastic problem. Thus, this study is motivated by the need of policy measures to establish a specific alternative to the problems of PS plastic pollution in ocean environments.

Exposure to fine particulate matter (PM₂.₅) remains a worldwide public health issue. However, epidemiological studies on the chronic health impacts of PM₂.₅ in the developing countries are hindered by the lack of monitoring data. Despite the recent development of using satellite remote sensing to predict ground-level PM₂.₅ concentrations in China, methods for generating reliable historical PM₂.₅ exposure, especially prior to the construction of PM₂.₅ monitoring network in 2013, are still very rare. In this study, a high-performance machine-learning model was developed directly at monthly level to estimate PM₂.₅ levels in North China Plain. We developed a random forest model using the latest Multi-angle implementation of atmospheric correction (MAIAC) aerosol optical depth (AOD), meteorological parameters, land cover and ground PM₂.₅ measurements from 2013 to 2015. A multiple imputation method was applied to fill the missing values of AOD. We used 10-fold cross-validation (CV) to evaluate model performance and a separate time period, January 2016 to December 2016, was used to validate our model's capability of predicting historical PM₂.₅ concentrations. The overall model CV R² and relative prediction error (RPE) were 0.88 and 18.7%, respectively. Validation results beyond the modeling period (2013–2015) shown that this model can accurately predict historical PM₂.₅ concentrations at the monthly (R² = 0.74, RPE = 27.6%), seasonal (R² = 0.78, RPE = 21.2%) and annual (R² = 0.76, RPE = 16.9%) level. The annual mean predicted PM₂.₅ concentration from 2013 to 2016 in our study domain was 67.7 μg/m3 and Southern Hebei, Western Shandong and Northern Henan were the most polluted areas. Using this computationally efficient, monthly and high-resolution model, we can provide reliable historical PM₂.₅ concentrations for epidemiological studies on PM₂.₅ health effects in China.

Mycotoxins are secondary metabolites produced by varieties of fungi that contaminate food and feed resources and are capable of inducing a wide range of toxicity. In the current study, we investigated developmental and behavioural toxicity in zebrafish larvae after exposure to six different mycotoxins; ochratoxin A (OTA), type A trichothecenes mycotoxin (T-2 toxin), type B trichothecenes mycotoxin (deoxynivalenol - DON), and zearalenone (ZEN) and its metabolites alpha-zearalenol (α-ZOL) and beta-zearalenol (β-ZOL). Developmental defects, hatching time, and survival were monitored until 96 h post fertilisation (hpf). The EC₅₀, LC₅₀, and IC₅₀ values were calculated. Subsequently, to assess behavioural toxicity, new sets of embryos were exposed to a series of non-lethal doses within the range of environmental and/or developmental concern. Results indicated that all the tested mycotoxins were toxic, they all induced developmental defects, and with the exception of OTA, all affected hatching time. Behavioural effects were only observed following exposure to OTA and ZEN and its metabolites, α ZOL and β ZOL. These results demonstrate that mycotoxins are teratogenic and can influence behaviour in a vertebrate model.

[Departement_IRSTEA]Eaux [TR1_IRSTEA]BELCA [TR2_IRSTEA]ARCEAU | International audience | extile dyes pose a significant challenge for water pollution due to the poor degradability of their complex aromatic structures (e.g., RR-120 and RBB-150). In order to minimize the harmful effects of RR-120 and RBB-150, the capacity of MgAl-layered double hydroxide for removing of these contaminants was studied herein. Batch adsorption experiments were conducted to investigate the effect of various operating parameters, such as solution pH, contact time, dye concentration, and temperature in order to provide optimal conditions for removal. Structural and morphological analyses were used to highlight the assembly and/or interaction LDH-dye. The state of equilibrium of RR-120 and RBB-150 adsorption was pH- and temperature-dependent and followed the pseudo-second-order rate model. Also, the equilibrium adsorption data of both dyes were found to adopt the Langmuir type isotherm model, which assumes a monolayer arrangement in LDH-dye. Furthermore, the effects of four major coexisting and competing mono- and divalent interlayer anions, such as NO3-, Cl-, CO32-, and SO42-, on the uptakes of RR-120 and RBB-150 were studied and the results showed that NO3- anions had insignificant effect on the uptakes of RR-120 and RBB-150 by MgAl. An equivalent study on the presence of both dyes in competitive trial adsorption/desorption from binary aqueous solution was investigated. And finally, the reuse operation of recovered material after dye adsorption was tested in up to 5 cycles of recyclability.

Biochemical indicators are potent tools to assess ecosystem functioning under anthropic and global pressures. Nevertheless, additional work is needed to improve the methods used for the measurement of these indicators, and for a more relevant interpretation of the obtained results. To face these challenges, the platform Biochem-Env aims at providing innovative and standardized measurement protocols, as well as database and information system favoring result interpretation and opening. Its skills and tools are also offered for expertise, consulting, training, and standardization. In addition, the platform is a service of a French Research Infrastructure for Analysis and Experimentation on Ecosystems, for research in environmental and agricultural sciences.

[Departement_IRSTEA]Ecotechnologies [TR1_IRSTEA]TED [ADD1_IRSTEA]Valoriser les effluents et déchets organiques | International audience | This study provides an alternative solution for the bioremediation of a recalcitrant pharmaceutical micropollutant. Clofibric acid (CLA) was chosen as target molecule, because of its environmental persistence and resistance to wastewater treatment technologies. The aim of this study was to investigate the potential of a phenol-resistant Pseudomonas aeruginosa strain isolated from the activated sludge to degrade CLA. In order to evaluate the effect of acclimation process with glucose as carbon co-substrate, two protocols were performed, in which the transfer of the inoculum is carried out either in the exponential growth phase or in the decline phase. The results showed a removal efficiency of CLA of 35% when cells in the decline phase were used for inoculation. In contrast, a very low removal yield (10%) was achieved when cells harvested in the exponential phase were used as inoculum. This work is the first one reporting on the capability of this bacterium to remove this drug. The obtained data showed that the isolated strain is able to degrade target molecule and might be a promising agent for the elimination of this refractory compound.

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The risk assessment of pesticides on soil fauna is an issue to protect agroecosystem sustainability. Enchytraeids are recognized as relevant soil bioindicators of chemical stress in agroecosystems. In laboratory, the reproduction test was found to be sensitive to reveal chemical impacts on enchytraeids. However, it does not allow to assess the impacts on ecological functions in which enchytraeids are involved. The objectives of this study were (i) to explore the feasibility of the bait-lamina test with enchytraeids under laboratory conditions and (ii) to compare its sensitivity with the Enchytraeid Reproduction Test. We exposed individuals of Enchytraeus albidus to two commercial formulations of fungicides widely used in Europe. The EC50 reproduction for the Swing® Gold (50 g L−1 epoxiconazole and 133 g L−1 dimoxystrobin) and the Cuprafor micro® (50% copper oxychloride) were respectively estimated at 1.66 ± 0.93 times the recommended dose and > 496 mg kg−1 of copper. However, no impact was found on the feeding activity of enchytraeids. The bait-lamina test thus appeared less sensitive than the Enchytraeid Reproduction Test to the tested fungicides. Despite that, this test which is achievable under laboratory conditions and allows assessing indirect effects of pesticides is quick, cheap, and easy to perform. It would deserve to be used to explore longer-exposure effects through the repeated addition of bait-lamina sticks.