Uptake and Effects of Graphene Oxide Nanomaterials Alone and in Combination with Polycyclic Aromatic Hydrocarbons in Zebrafish

Because of its surface characteristics, once in the aquatic environment, graphene could act as a carrier of pollutants, such as polycyclic aromatic hydrocarbons (PAHs), to aquatic organisms. In this study we aimed to (1) assess the capacity of graphene oxide (GO) to sorb PAHs and (2) to evaluate the toxicity of GO alone and in combination with PAHs on zebrafish embryos and adults. GO showed a high sorption capacity for benzo(a)pyrene (B(a)P) (98% of B(a)P sorbed from a nominal concentration of 100 mu g/L) and for other PAHs of the water accommodated fraction (WAF) of a naphthenic North Sea crude oil, depending on their log Kow (95.7% of phenanthrene, 84.4% of fluorene and 51.5% of acenaphthene). In embryos exposed to different GO nanomaterials alone and with PAHs, no significant mortality was recorded for any treatment. Nevertheless, malformation rate increased significantly in embryos exposed to the highest concentrations (5 or 10 mg/L) of GO and reduced GO (rGO) alone and with sorbed B(a)P (GO-B(a)P). On the other hand, adults were exposed for 21 days to 2 mg/L of GO, GO-B(a)P and GO co-exposed with WAF (GO + WAF) and to 100 mu g/L B(a)P. Fish exposed to GO presented GO in the intestine lumen and liver vacuolisation. Transcription level of genes related to cell cycle regulation and oxidative stress was not altered, but the slight up-regulation of cyp1a measured in fish exposed to B(a)P for 3 days resulted in a significantly increased EROD activity. Fish exposed to GO-B(a)P and to B(a)P for 3 days and to GO + WAF for 21 days showed significantly higher catalase activity in the gills than control fish. Significantly lower acetylcholinesterase activity, indicating neurotoxic effects, was also observed in all fish treated for 21 days. Results demonstrated the capacity of GO to carry PAHs and to exert sublethal effects in zebrafish.This work has been funded by University of the Basque Country (predoctoral grant to IMA PIFBUR15/15), Basque Government (consolidated research group IT810-13 and IT1302-19), Spanish Ministry of Economy and Competitiveness project NACE (CTM2016-81130-R), French National Research Agency (No.-10-IDEX-03-02) and Cluster of Excellence Continental To coastal Ecosystems-COTE (ANR-10-LABX 45). Thanks to staff at Driftslaboratoriet Mongstad, Equinor (former Statoil) for supplying the sample of crude oil used in the experiments. The authors thank for technical and human support provided by SGIker (UPV/EHU/ERDF, EU)

Biomarker responses and accumulation of polycyclic aromatic hydrocarbons in Mytilus trossulus and Gammarus oceanicus during exposure to crude oil

In the brackish water Baltic Sea, oil pollution is an ever-present and significant environmental threat mainly due to the continuously increasing volume of oil transport in the area. In this study, effects of exposure to crude oil on two common Baltic Sea species, the mussel Mytilus trossulus and the amphipod Gammarus oceanicus, were investigated. The species were exposed for various time periods (M. trossulus 4, 7, and 14 days, G. oceanicus 4 and 11 days) to three oil concentrations (0.003, 0.04, and 0.30 mg L−1 based on water measurements, nominally aimed at 0.015, 0.120, and 0.750 mg L−1) obtained by mechanical dispersion (oil droplets). Biological effects of oil exposure were examined using a battery of biomarkers consisting of enzymes of the antioxidant defense system (ADS), lipid peroxidation, phase II detoxification (glutathione S-transferase), neurotoxicity (acetylcholinesterase inhibition), and geno- and cytotoxicity (micronuclei and other nuclear deformities). In mussels, the results on biomarker responses were examined in connection with data on the tissue accumulation of polycyclic aromatic hydrocarbons (PAH). In M. trossulus, during the first 4 days of exposure the accumulation of all PAHs in the two highest exposure concentrations was high and was thereafter reduced significantly. Significant increase in ADS responses was observed in M. trossulus at 4 and 7 days of exposure. At day 14, significantly elevated levels of geno- and cytotoxicity were detected in mussels. In G. oceanicus, the ADS responses followed a similar pattern to those recorded in M. trossulus at day 4; however, in G. oceanicus, the elevated ADS response was still maintained at day 11. Conclusively, the results obtained show marked biomarker responses in both study species under conceivable, environmentally realistic oil-in-seawater concentrations during an oil spill, and in mussels, they are related to the observed tissue accumulation of oil-derived compounds

Passive Sampling as a Tool to Assess Atmospheric Pesticide Contamination Related to Vineyard Land Use

The massive use of pesticides in agriculture has led to widespread contamination of the environment, particularly the atmospheric compartment. Thirty-six pesticides, most used in viticul-ture, were monitored in ambient air using polyurethane foams as passive air samplers (PUF-PAS). Spatiotemporal data were collected from the samplers for 10 months (February–December 2013), using two different sampling times (1 and 2 months) at two different sites in a chateau vineyard in Gironde (France). A high-volume active air sampler was also deployed in June. Samples were extracted with dichloromethane using accelerated solvent extraction (ASE) (PUFs from both passive and active) or microwave-assisted extraction (MAE) (filters from active sampling). Extracts were analyzed by both gas and liquid chromatography coupled with tandem mass spectrometry. A total of 23 airborne pesticides were detected at least once. Concentrations in PUF exposed one month ranged from below the limits of quantification (LOQs) to 23,481 ng PUF−1. The highest concentrations were for folpet, boscalid, chlorpyrifos-methyl, and metalaxyl-m—23,481, 17,615, 3931, and 3324 ng PUF−1. Clear seasonal trends were observed for most of the pesticides detected, the highest levels (in the ng m−3 range or the µg PUF−1 range) being measured during their application period. Impregnation levels at both sites were heterogeneous, but the same pesticides were involved. Sampling rates (Rs) were also estimated using a high-volume active air sampler and varied significantly from one pesticide to another. These results provide preliminary information on the seasonality of pesticide concentrations in vineyard areas and evidence for the effectiveness of PUF-PAS to monitor pesticides in ambient air. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.COntinental To coastal Ecosystems: evolution, adaptability and governanc

One Planet: One Health. A Call to Support the Initiative on a Global Science-Policy Body on Chemicals and Waste

The chemical pollution crisis severely threatens human and environmental health globally. To tackle this challenge the establishment of an overarching international science–policy body has recently been suggested. We strongly support this initiative based on the awareness that humanity has already likely left the safe operating space within planetary boundaries for novel entities including chemical pollution. Immediate action is essential and needs to be informed by sound scientific knowledge and data compiled and critically evaluated by an overarching science–policy interface body. Major challenges for such a body are (i) to foster global knowledge production on exposure, impacts and governance going beyond data-rich regions (e.g., Europe and North America), (ii) to cover the entirety of hazardous chemicals, mixtures and wastes, (iii) to follow a one-health perspective considering the risks posed by chemicals and waste on ecosystem and human health, and (iv) to strive for solution-oriented assessments based on systems thinking. Based on multiple evidence on urgent action on a global scale, we call scientists and practitioners to mobilize their scientific networks and to intensify science–policy interaction with national governments to support the negotiations on the establishment of an intergovernmental body based on scientific knowledge explaining the anticipated benefit for human and environmental health

Simulated conservative tracer as a proxy for S-metolachlor concentration predictions compared to POCIS measurements in Arcachon Bay

The work presented here aims at comparing monitoring of S-metolachlor, the major pesticide in use in the Arcachon Bay (South West of France, transitional coastal area), by chemical analysis (monthly passive sampling) and contaminant dissipation modeling from sources (Mars-2D model). The global strategy consisted in i) identifying the major sources of S-metolachlor to the Bay, ii) monitoring these sources for 12 months, and iii) comparing modeled data in the Bay based on measured inputs, to chemical measurements made inside the Bay along with the 12-month source monitoring. Results first showed that the major S-metolachlor surface inputs to the Arcachon Bay are mainly from one single source. Modeled and measured data were in good agreement at 5 sites in the Bay, both in terms of concentration range and seasonal trends. Modeling thus offers a cost-effective solution for monitoring contaminants in transitional waters, overcoming in addition the technical limitations for measuring pg L−1 or lower levels in coastal waters. However, we highlighted that secondary sources may affect accuracy at local level

The effect of the main physicochemical properties of polycyclic aromatic hydrocarbons on their water/sediments distribution

International audiencePolycyclic aromatic hydrocarbons (PAHs) are environmental contaminants that continue to attract researchers' attention until these days due to their toxicity and their multisource emission. In this study, levels of 17 active molecules of PAHs were investigated in marine and continental Lebanese aquatic systems. The results showed that Lebanese seawater is more contaminated than several other sites on the Mediterranean Sea. On the marine side, the total concentration of PAHs ranges from 55.7 to 2683.8 ng L−1 in water and from 19.09 to 2025.03 ng g−1 in sediments. On the continental side, the total concentration ranges from 465.7 to 1399.9 ng L−1 in water and from 72.6 to 1074.7 ng g−1 in sediments presenting higher contamination and detection frequency than the marine sites. Pearson test was applied to determine the preference of PAHs toward one of the phases and showed that when the number of rings, the molecular mass and the log Ko/w increase, PAHs accumulate in sediments, and when the water solubility and the vapor pressure of PAHs increase, they tend to remain in the aqueous phase. Moreover, PAHs in Lebanese sediments were combustion-originated and resulted mainly from industrial sites set next to aquatic systems and heavy traffic especially along the Lebanese coastline. Regarding the toxicity effect, the use of the ERL/ERM approach revealed that few sites have individual PAHs levels that may occasionally cause biological adverse effects to benthic organisms; nevertheless, the ecosystem risk of PAHs in Lebanese sediments is low

Biomarker responses and accumulation of polycyclic aromatic hydrocarbons in Mytilus trossulus and Gammarus oceanicus during exposure to crude oil

In the brackish water Baltic Sea, oil pollution is an ever-present and significant environmental threat mainly due to the continuously increasing volume of oil transport in the area. In this study, effects of exposure to crude oil on two common Baltic Sea species, the mussel Mytilus trossulus and the amphipod Gammarus oceanicus, were investigated. The species were exposed for various time periods (M. trossulus 4, 7, and 14 days, G. oceanicus 4 and 11 days) to three oil concentrations (0.003, 0.04, and 0.30 mg L−1 based on water measurements, nominally aimed at 0.015, 0.120, and 0.750 mg L−1) obtained by mechanical dispersion (oil droplets). Biological effects of oil exposure were examined using a battery of biomarkers consisting of enzymes of the antioxidant defense system (ADS), lipid peroxidation, phase II detoxification (glutathione S-transferase), neurotoxicity (acetylcholinesterase inhibition), and geno- and cytotoxicity (micronuclei and other nuclear deformities). In mussels, the results on biomarker responses were examined in connection with data on the tissue accumulation of polycyclic aromatic hydrocarbons (PAH). In M. trossulus, during the first 4 days of exposure the accumulation of all PAHs in the two highest exposure concentrations was high and was thereafter reduced significantly. Significant increase in ADS responses was observed in M. trossulus at 4 and 7 days of exposure. At day 14, significantly elevated levels of geno- and cytotoxicity were detected in mussels. In G. oceanicus, the ADS responses followed a similar pattern to those recorded in M. trossulus at day 4; however, in G. oceanicus, the elevated ADS response was still maintained at day 11. Conclusively, the results obtained show marked biomarker responses in both study species under conceivable, environmentally realistic oil-in-seawater concentrations during an oil spill, and in mussels, they are related to the observed tissue accumulation of oil-derived compounds

Amélioration de la technique de quantification du dichlorvos dans les eaux dans le cadre de la DCE

La DCE a défini des Normes de Qualité Environnementale (NQE) pour les substances identifiées comme prioritaires. Parmi les substances ciblées, le dichlorvos, insecticide acaricide aujourd’hui interdit en France pose un challenge analytique car sa NQE est très faible (NQEeau douce : 0,6 ng/L, NQE eau marine : 0,06 ng/L, ce qui implique de pouvoir atteindre une limite de quantification (LQ) de 0,02 ng/L selon la directive QA/QC (2009/90/CE). L’objectif principal de ce travail est d’atteindre la limite de quantification visée (0,02 ng/L) à travers l’amélioration des techniques d’échantillonnage, d’extraction et d’analyse du dichlorvos. L’analyse est faite en chromatographie en phase liquide. Le mode d’acquisition qui a été choisi pour le développement de la quantification du dichlorvos par spectrométrie de masse en tandem est le mode MRM (Multiple Reaction Monitor). Le type de source utilisée est une source à ionisation par électronébuliseur (ESI : electrospray ionization source) en mode positif. En parallèle de l’amélioration de la méthodologie analytique, un travail particulier a été mené sur la calibration afin d’obtenir un taux d’échantillonnage pour le dichlorvos et le protocole d’extraction des échantillonneurs passifs de type POCIS (Polar Organic Chemical Integrative Sampler) a également été optimisé. Les développements réalisés (LC/MS/MS couplé aux capacités de concentration des échantillonneurs passifs de type POCIS) ont permis d’abaisser la limite de quantification du dichlorvos à 0,9 pg/L (ou 0,0009 ng/L) pour une durée d’exposition de 15 jours. Ces performances analytiques obtenues sont compatibles avec le suivi du dichlorvos selon les performances demandées par les directives Cadre sur l’Eau (DCE) (2000/60/EC) et directive QA/QC (2009/90/CE).    

Contribution à l'optimisation de la technique POCIS: Amélioration de la quantification du dichlorvos (dans le cadre de la DCE) et développement d'une nouvelle géométrie POCIS

La Directive Cadre sur l’Eau (DCE) a défini des Normes de Qualité Environnementale (NQE) pour les substances identifiées comme prioritaires. Parmi les substances ciblées, le dichlorvos, insecticide acaricide aujourd’hui interdit en France pose un challenge analytique car sa NQE est très faible (NQEeau douce : 0,6 ng/L, NQE eau marine : 0,06 ng/L, ce qui implique de pouvoir atteindre une limite de quantification (LQ) de 0,02 ng/L pour l’eau douce et 0,02 ng/L pour l’eau marine selon la directive QA/QC (2009/90/CE). L’objectif principal de ce travail est d’atteindre les limites de quantification visée à travers l’amélioration des techniques d’échantillonnage, d’extraction et d’analyse du dichlorvos. L’analyse est faite en chromatographie en phase liquide. Le mode d’acquisition qui a été choisi pour le développement de la quantification du dichlorvos par spectrométrie de masse en tandem est le mode MRM (Multiple Reaction Monitor). Le type de source utilisée est une source à ionisation par électronébuliseur (ESI : electrospray ionization source) en mode positif. L’amélioration de la méthodologie analytique a permis d’obtenir une limite de quantification instrumentale de 0,2 pg.inj. En parallèle de l’amélioration de la méthodologie analytique, un travail particulier a été mené sur la calibration afin d’obtenir un taux d’échantillonnage pour le dichlorvos et le protocole d’extraction des échantillonneurs passifs de type POCIS (Polar Organic Chemical Integrative Sampler) a également été optimisé. Les développements réalisés (LC/MS/MS) couplés aux capacités de concentration des échantillonneurs passifs de type POCIS ont été testés sur de la phase OASIS HLB supplémenté. Ces tests ont permis d’obtenir une limite de quantification théorique du dichlorvos à 0,9 pg/L (ou 0,0009 ng/L) pour une durée d’exposition de 15 jours. Cependant la confrontation de ce protocole à des échantillons de POCIS exposés en milieu naturel et aux effets matriciels inhérents aux échantillons environnementaux montrent une limite de quantification effective variant entre 0,15 ± 0,02 et 0,36 ± 0,16 ng/L. Ces performances analytiques obtenues sur les échantillons environnementaux sont juste compatibles avec le suivi du dichlorvos selon les performances demandées par les directives DCE: 2000/60/EC et QA/QC 2009/90/CE sur les eaux douces, mais ne sont à l’heure actuelle pas satisfaisantes pour les eaux marines. Une étape de purification de l’extrait serait à développer pour lever les effets matriciels impactant les performances de la méthodologie d’analyse. Afin d'augmenter l'opérationnalité de la méthode (réduire les opérations préalables à la mise en place et suite à la récupération; limiter les risques de contamination; réduire le volume et le poids du système pour faciliter le stockage et diminuer les coûts de transport), les tests d'une nouvelle "géométrie" de cage ont été poursuivis (Gonzalez et al, 2012). Les résultats obtenus sont en accord avec l'étude précédente.    

Assessment of organochlorine contamination source and ecological risk in the Litani River: polychlorinated biphenyls and organochlorinated pesticides in surface sediments

In this paper, we investigate for the first time the contamination source and the ecological risk associated to organochlorinated compounds in the Litani system. For this purpose, the levels of 7 polychlorinated biphenyls (PCBs) and 13 organochlorinated pesticides (OCPs) were assessed, using a microwave-assisted extraction coupled to gas chromatography-electron capture detector (MAE/GC-ECD) method, in surficial sediments from 30 sites along the main course of the river, two major tributaries, and the Quaraoun Lake. ∑7PCBs exhibited total concentrations ranging from 0.11 to 8 ng g−1 of dry weight and are not able apparently to pose ecological risks since none of the samples showed concentration above the effects range low (ERL) guideline (22.7 ng g−1). The detected levels of OCPs in the river were significantly higher than those of PCBs; ∑13OCPs range from 0.5 to 46.5 ng g−1 of dry weight. Overall, the integrated eco-toxicological risk imposed by the organochlorine contamination in the Litani River, estimated as the mean effects range medium quotient (mERMq), is considered low with risk probability lower than 21% in all sites. The six dichlorodiphenyltrichloroethane-based pesticides (∑6DDT) contributed to more than 70% of the mERMq in 15 over the 29 included sites. Moreover, the approach of ∑6DDT/∑7PCB ratios was applied to investigate the contamination source. ∑6DDT/∑7PCB was higher than one in all samples suggesting that the organochlorine contamination result from agricultural activities set in the surrounding areas of the Litani River