Archives of Environmental Contamination and Toxicology最新文献

Geothermal vents can constitute local significant sources of mercury (Hg) in the environment. The geothermal power plant of Bouillante (Guadeloupe, Lesser Antilles) artificially enhances the release of hydrothermal water in shallow areas of the bay. To assess the impact of this release on the Hg transfer in the environment, Hg concentrations were assessed in sediments, sulphur-oxidising bacteria and six animal species (urchin, sponges and fish) with various diets and trophic levels from the Bouillante Bay and a distant Control Site. Concentrations of Hg in all samples from Bouillante were greater than those from the Control Site (2-627 times higher). A comparison with the Hg concentrations reported in the literature for similar sample types reveals that they are abnormally high in most Bouillante samples suggesting a local Hg contamination imputable to the release of Hg hydrothermal water. Rocky pebbles of the shallow discharge channel are covered by a mat of sulphur-oxidising bacteria presenting high concentration of Hg (13 µg g^-1). Through analysis of species with various diet, two pathways of Hg integration into Bouillante's food webs were emphasised. First, greater Hg concentrations in filter feeders (sponges ×3 and bivalves ×10) not consuming bacterial mats and liver/muscle ratios in fishes suggest that discharge waters enhance the exposure of marine organisms to dissolved inorganic Hg (i.e., waterborne pathway). Second, greater Hg concentrations in opportunistic animals such as the fish Acanthurus bahianus (×49) and the sea urchin Diadema antillarum (×50) known to ingest sulphur-bacterial mats from the discharge channel suggest that these chemosynthetic bacteria play a role in the integration (i.e., dietary pathway) and transfer of Hg in local biota, which enlightens the consideration of vent fields as natural sources of Hg.

In recent years, 1,4-dioxane has emerged as a pollutant of increasing concern following widespread detection in the aquatic environment of several countries. This persistent contaminant with specific physical and chemical properties can be rapidly dispersed and transported to river banks, groundwater and drinking water. Given the limited data on its occurrence in France, it was considered necessary to assess the potential exposure of the French population to this compound in drinking water. An analytical method based on solid-phase extraction (SPE) combined with gas chromatography tandem mass spectrometry (GC-MS/MS) was developed and validated during this study with a limit of quantification (LOQ) of 0.15 µg/L. Recoveries in natural water matrices ranged from 113 to 117% with a relative bias not exceeding 17%. This method was used for a nationwide campaign at almost 300 sites, evenly distributed over 101 French départements (administrative units), including some that were overseas. Of the 587 samples analysed, only 8% had a concentration that was greater than or equal to the LOQ. 1,4-Dioxane was detected mainly (63%) in raw and treated water from sites associated with historical industrial practices related to the use of chlorinated solvents. Concentrations of 1,4-dioxane ranging from 0.19 to 2.85 µg/L were observed in the raw water and from 0.18 to 2.46 µg/L in the treated water. Drinking water treatment plants using ozonation, granular activated carbon and chlorination have limited effectiveness in the removal of 1,4-dioxane. The results of this study are the first step towards bridging the knowledge gap in the occurrence of 1,4-dioxane in France.

Wetlands play a crucial role in providing valuable ecosystem services, including the removal of various pollutants. In agricultural basins, wetlands are exposed to agrochemical loads. This study aims to assess the attenuation effect of the ubiquitous macrophyte Azolla spp. on the toxicity of lambda-cyhalothrin to sensitive aquatic organisms. An indoor mesocosm experiment was conducted to compare the concentration of lambda-cyhalothrin at different time points after pesticide application in vegetated and unvegetated treatments, including a control without pesticide addition. Toxicity tests were performed throughout the experiment on three organisms: a fish (Cnesterodon decemmaculatus), a macroinvertebrate (Hyalella curvispina), and an amphibian (Boana pulchella). The results demonstrated that lambda-cyhalothrin concentration and toxicity in water were significantly lower in the Azolla spp. treatment. Furthermore, the half-life of lambda-cyhalothrin decreased from 1.2 days in the unvegetated treatment to 0.4 days in the vegetated treatment. The vegetated treatment also resulted in a significantly lower mortality rate for both H. curvispina and C. decemmaculatus. However, no mortality was observed in B. pulchella for any of the treatments. Sublethal effects were observed in this organism, such as lateral bending of the tail and impairment of the ability to swim, which were attenuated in the vegetated treatment. We conclude that Azolla spp. can effectively reduce the concentration and toxicity of lambda-cyhalothrin, suggesting its potential use in farm-scale best management practices to mitigate the effects of pesticide loads from adjacent crops.

In this work, the concentrations of hazardous elements (As, Cd and Pb) in the edible portion of the Perna perna mussel from Southeast Brazil were analyzed to understand the effects of the COVID-19 pandemic on the coastal environment and to evaluate the quality of this fishery resource. Decreases in anthropogenic chemical outputs to the environment were expected to occur during the COVID-19 pandemic, with decreases in element concentrations in mussels. The ranges of median concentrations (µg g^-1 dw) in the pre- and pandemic periods were 5.4-16.1 and 2.2-10.6 for As; 0.2-0.6 and 0.1-0.5 for Cd; and 1.2-3.2 and 0.7-1.8 for Pb, respectively. Temporal variations (prepandemic x pandemic) were more significant than spatial variations (five sampling sites). The relationships between the concentrations of hazardous elements and isotopic ratios (δ¹⁵N and δ¹³C) suggested that food sources were more diverse across the sampling sites during the pandemic period, when individuals exhibited less efficient trophic transfer. The concentrations of Cd and Pb were below the tolerable maximum limit, whereas for As, they were above the limit; however, these concentrations are not a risk to human health, as most As was present in the least toxic organic form. The intake estimates were below the tolerable intake limits, and only Pb concentrations are at risk of causing concern if the intake of mussels increases. This is the first study in Brazil that presents a spatial-temporal comparison of hazardous elements in marine fauna considering COVID-19 as a temporal landmark. The results are of interest for both public health and environmental health management in a post-COVID-19 scenario.

In 2015, a breach in the Fundão Dam in Mariana (Minas Gerais State, Brazil) resulted in the release of contaminated tailings into the Doce River basin. This accident increased the concentrations of arsenic (As), lead (Pb), cadmium (Cd), vanadium (V), and manganese (Mn) in the soil, posing a potential hazard to the physiology of native species. The purpose of this study was to assess whether chlorophyll a fluorescence (ChlF) in Allagoptera arenaria and Guapira pernambucensis changed following this accident when tested under different precipitation regimes in relation to soil properties and metal(loid) absorption. Our research was conducted in two sites located in the state of Espírito Santo in southeastern Brazil. Five independent biological replicates of A. arenaria and G. pernambucensis were selected at each site for nutritional and chlorophyll a fluorescence analysis. Five years after the dam rupture, A. arenaria and G. pernambucensis had absorbed As, Pb, and V. The increased amounts of metal(loid)s absorbed did not significantly impair the OJIP curve configuration for either species during the evaluated periods. However, A. arenaria at Biological Reserve of Comboios (RBC) during the rainy season showed increases in the values of maximum quantum yield of PSII photochemistry (φP₀) and total performance index on absorption basis (PI_TOTAL). These changes indicated more efficient tolerance mechanisms for increases in the concentrations of As, Pb, and V than those observed in G. pernambucensis. It was concluded that A. arenaria and G. pernambucensis exhibited an acclimation strategy in response to increased absorption of metal(loid)s.

Delhi's agricultural hub, nestled along the Yamuna floodplains, faces soil and water contamination issues. Utilizing organic waste composts is gaining traction to improve soil quality, but uncertainties remain about their efficacy in reducing harmful elements. The study examined three Amaranthaceae cultivars, comparing organic waste composts with chemical fertilizer to evaluate correlations between heavy metals, antioxidants, and antinutrients to assess their bioremediation potential. "Heavy metals" or "potentially toxic elements (PTE)" levels in soil and leaves were measured by ICP-MS, while antioxidants and antinutrients were analyzed with UV-VIS spectroscopy. The study revealed higher PTE levels in floodplain soil, with Cr, Ni, and Cd exceeding safe limits in all cultivars. Compost amendments reduced these pollutants by 28% compared to chemical fertilizers, decreasing bioaccumulation by 20%. Health risk assessments showed lower risks in compost-amended cultivars. Additionally, compost amendment displayed a stronger negative correlation between PTE and antioxidants, suggesting effective bioremediation. Overall, compost amendments offer promise for mitigating PTE in metropolitan floodplains.

The research assessed the exposure to total mercury (THg), lead (Pb), and arsenic (As) in Colombian wetland species of different trophic levels Platalea ajaja, Dendrocygna autumnalis and Nannopterum brasilianus. The results show high THg blood levels in P. ajaja (811.00 ± 349.60 µg L^-1) and N. brasilianus (209.50 ± 27.92 µg L^-1) with P. ajaja possibly exhibiting adverse effects. Blood Pb concentration was high in D. autumnalis (212.00 ± 208.10 µg L^-1) and above the threshold for adverse effects, suggesting subclinical poisoning. Levels of blood As were below the assumed threshold for detrimental effect (20 μg L^-1). The mean concentration of feather THg was below the assumed natural background levels (5 µg g^-1) for all three species. Feather Pb levels exceeded the levels for assumed threshold effects in all sampled N. brasilianus (7.40 ± 0.51 µg g^-1). Results for feather As concentration were below the threshold for adverse impacts in all species, although a positive correlation between As and THg concentrations was detected in P. ajaja feathers. The overall results could help understand how metal(loid)s biomagnify through trophic levels and how wetland species may serve as environmental indicators. By exploring the interactions of metal(loid)s within different matrices and body, this study offers insights into the dynamics of contaminant accumulation and distribution in the environment. This concept can be applied to wetlands worldwide, where bird species can serve as indicators of ecosystem health and the presence of contaminants such as heavy metals and metalloids.

Insects are impacted by pollutants in their environments and food sources. Herein, we set out a semi-field study to assess the impact of environmental heavy metal contamination on developmental parameters, energy reserves, and acidic and alkaline phosphatases in the larval Agrotis ipsilon (Lepidoptera: Noctuidae). Castor leaves from contaminated and uncontaminated (reference site) areas were fed to A. ipsilon larvae in all treatments. The heavy metal concentrations in the plant from different areas (contaminated and reference sites) and in the larvae were analyzed. Toxic effects were observed in the larvae feeding on the leaves from the metal contaminated areas. Larval and pupal weights, growth indices, and larval fitness were all significantly lower than in the reference group. Likewise, in the third and fourth instars, there was a significant decrease in both the survival and moth emergence rates. In contrast, the pupation duration was significantly longer. Total protein, lipid, and glycogen content showed significant reductions in treated larvae. Larval homogenate samples contaminated with heavy metals showed a significant increase in acid- and alkaline- phosphatase levels. The results obtained could provide a basis for a long-term evaluation of the risk associated with heavy metals and their impact on plant populations and important agricultural pests.

Wolverines are facultative scavengers that feed near the top of terrestrial food chains. We characterized concentrations of mercury and other trace elements in tissues of wolverine from a broad geographic area, representing much of their contemporary distribution in northwestern North America. We obtained tissues from 504 wolverines, from which mercury was measured on muscle (n = 448), kidney (n = 222), liver (n = 148), hair (n = 130), and brain (n = 52). In addition, methylmercury, seven trace elements (arsenic, cadmium, chromium, cobalt, lead, nickel, selenium), and arsenic compounds were measured on a subset of samples. Concentrations of mercury and other trace elements varied between tissues and were generally highest in kidney compared to brain, liver and muscle. Mercury was predominately as methylmercury in brain and muscle, but largely as inorganic mercury in liver and kidney. Mercury concentrations of hair were moderately correlated with those of internal tissues (Pearson r = 0.51-0.75, p ≤ 0.004), making hair a good non-lethal indicator of broad spatial or temporal differences in mercury exposure to wolverine. Arsenobetaine was the dominant arsenic compound identified in tissues, and arsenite, arsenocholine and dimethylarsinic acid were also detected. A preliminary risk assessment suggested the cadmium, lead, mercury, and selenium concentrations in our sample of wolverines were not likely to pose a risk of overt toxicological effects. This study generated a comprehensive dataset on mercury and other trace elements in wolverine, which will support future contaminants study of this northern terrestrial carnivore.

Complex mixtures of chemicals present in groundwater at legacy-contaminated industrial sites can pose significant risks to adjacent surface waters. The combination of short-term molecular and chronic apical effect assessments is a promising approach to characterize the potential hazard of such complex mixtures. The objectives of this study were to: (1) assess the apical effects (survival, growth, development, and liver histopathology) after chronic exposure of early life stages (ELSs) of fathead minnows (FHM; Pimephales promelas) to contaminated groundwater from a legacy-contaminated pesticide manufacturing and packaging plant, and (2) identify possible molecular mechanisms responsible for these effects by comparing results to mechanistic outcomes previously determined by a short-term reduced transcriptome assay (EcoToxChips). This study revealed a significant increase in mortality and prevalence of spinal curvatures, as well as a significant reduction in the length of FHMs exposed to the groundwater mixtures in a concentration-dependent manner. There was an increasing trend in the prevalence of edema in FHMs, though not significantly different from controls. Additionally, no histopathological effects were observed in the liver of FHMs exposed to the groundwater mixtures. Short-term molecular outcomes determined in a parallel study were found to be informative of chronic apical outcomes, including cardiotoxicity, spinal deformities, and liver toxicity. Overall, the results observed in this study demonstrated that short-term transcriptomics analyses could support the hazard assessment of complex contaminated sites.