Archives of Environmental Contamination and Toxicology最新文献

Aquatic organisms can uptake metals directly from contaminated water or by consuming contaminated prey. Knowing the relative importance of these routes is critical to understand how metals enter and move through aquatic food webs. We previously established that nymphs of the aquatic dragonfly Erythemis simplicicollis accumulate elevated copper (Cu) concentrations when living in contaminated wetlands, but the route of uptake was not identified. In this study, we evaluate copper accumulation with a model two-trophic-level laboratory food chain comprised of E. simplicicollis dragonfly nymphs as predators and Aedes aegypti mosquito larvae as prey to gain better insight into Cu accumulation dynamics in these aquatic insect predators. Treatments consisted of dragonfly nymphs exposed to copper through diet (A. aegypti larvae prey exposed to 100 µg/L Cu-contaminated water), water (100 µg/L Cu), diet + water, and a control. Each treatment included 15 replicates, and 10 pretreatment nymphs were analyzed. Exposures lasted 32 days or until nymph death. Copper accumulation in nymphs and nymph mortality was compared among treatments. Eating contaminated prey did not elevate copper concentrations in E. simplicicollis. In contrast, highest copper concentrations accumulated in E. simplicicollis when exposed to contaminated water, in both the water-only and in the diet + water treatments. Additionally, mortality was greater when exposed to copper-contaminated water. Even though the nymphs did not trophically accumulate Cu, direct uptake of Cu from water provides a point of Cu entry into a food chain.

Artisanal and small-scale gold mining (ASGM) is the largest anthropogenic source of mercury globally. Few studies have explored how this toxicant affects avian wildlife in Indonesia, an ASGM hotspot. Here, we use feather samples from museum specimens (n = 92) of Indonesian birds to examine changes through time in methylmercury (MeHg), diet, and foraging habitat (inferred from stable isotope ratios of nitrogen, δ¹⁵N, and carbon, δ¹³C, respectively). We ask how MeHg changes between time period (1860–1980 vs. 1980–2019) given increases in mercury emissions due to ASGM and describe how foraging guild and among-species variation in diet influence Indonesian bird feather MeHg concentrations. Time period was not a significant factor, with specimens associated with increased ASGM activity (collected post-1980) not significantly higher in MeHg concentrations compared to specimens collected pre-1980. Feather MeHg concentrations varied significantly among species, foraging guilds, and by habitat use. Carnivore and insectivore MeHg concentrations were above thresholds associated with sublethal effects. This is the first report of MeHg in Indonesian passerines, kingfishers, and woodpeckers. It provides critical information on mercury exposure in a region with high avian diversity that is severely impacted by mercury pollution.

Arsenic (As) is naturally occurring and is found in different forms, some of which are considered toxic to human health and frequently present in fishery resources. The aim of this work was to determine the contribution of toxic As species to the total As in muscle of two commercial fish species (Micropogonias furnieri and Urophycis brasiliensis) and to assess the toxicological risk associated with their consumption, considering different exposed groups. The total As concentrations found exceeded local guideline recommendations (> 1 mg kg⁻¹ wet weight), but the concentrations of the toxic As species were below this threshold. The inorganic As levels do not exceed the international guideline recommendations (0.03–0.15 μg kg⁻¹ bw per day of iAs). Both interspecific and intraspecific differences in As concentrations were found. Non-carcinogenic and carcinogenic risk values indicated that the exposed groups would not experience health risks through consumption of either fish species. However, due to the lack of an established safe consumption limit for iAs or As species worldwide, there are currently no legal tools to ensure that these fish species are safe for human consumption.

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In situ assessment of metal bioavailability is crucial for evaluating the degree of contamination in aquatic systems. This study evaluated the bioavailability of Al, Fe, Mn and Zn in water from three sites in a decommissioned mining area near the city of Poços de Caldas (State of Minas Gerais, Brazil). A multi-tool approach was used, combining DGT, transplanted fish (Oreochromis niloticus) and water samples (total and dissolved metal concentration analyses). Samples were taken at 14, 28 and 42-day intervals. Livers, gills and muscles of transplanted fish were analyzed after acid digestion in microwaves and determined by ICP-OES. Significant increases in transplanted fish for Mn and Zn concentrations were observed in the gills. Total and dissolved concentrations showed large fluctuations, possibly influenced by factors such as the rainy season, pH changes, and varying effluent discharges at each sampling point. The concentration of the element measured by DGT devices, proved to be an effective indicator of temporal and spatial variations in the bioavailable levels of Al, Fe, Mn and Zn across all sites analyzed. However, the weak correlations between the different monitoring methods highlight their complementary nature, as each approach captures distinct aspects of metal bioavailability. This underscores the importance of integrating multiple methodologies to provide a more comprehensive understanding of metal dynamics in complex environmental scenarios.

The formulation of reasonable concentration classification standards can significantly enhance the protection of populations against atmospheric heavy metals, and the development of these standards should be grounded in national-level probabilistic risk assessment to establish multiple grading benchmarks. In this study, the probabilistic health risk assessment model was used for the first time to assess the health risks of hazardous metals [arsenic (As), cadmium (Cd), cobalt (Co), chromium (Cr), mercury (Hg), manganese (Mn), nickel (Ni), lead (Pb), and vanadium (V)] based on a publication dataset containing 57,737 PM_2.5-bound heavy metal samples from China. Our results showed that the average non-carcinogenic risk attributed to heavy metals in all provinces of China was less than 1. In contrast, the average carcinogenic risk was greater than 10^–6 in all provinces. The logarithmic mean non-carcinogenic health risks for the eight non-carcinogenic metals were ranked as follows: V (− 1.55 ± 0.96) > As (− 1.79 ± 0.96) > Mn (− 1.84 ± 0.82) > Co (− 2.05 ± 0.89) > Cd (− 2.14 ± 0.94) > Ni (− 2.59 ± 0.92) > Cr (− 3.26 ± 0.93) > Hg (− 4.86 ± 0.91), while the logarithmic mean carcinogenic health risk for the seven carcinogenic metals was Cr (− 5.33 ± 0.93) > V (− 5.79 ± 0.96) > As (− 5.98 ± 0.96) > Co (− 6.32 ± 0.89) > Cd (− 6.89 ± 0.94) > Pb (− 7.02 ± 0.93) > Ni (− 7.22 ± 0.92). The metals that contributed most to the non-carcinogenic and carcinogenic risks were V (35.86%) and Cr (57.61%), respectively. Through probabilistic risk assessment, we constructed seven-level health benchmarks for carcinogenic metals (As, Cd, Co, Cr, Ni, Pb, V). These benchmarks of extremely low health risk for the seven carcinogenic metals (As, Cd, Co, Cr, Ni, Pb, V) were 0.00037 μg/m³, 0.0011 μg/m³, 0.00012 μg/m³, 0.00011 μg/m³, 0.0043 μg/m³, 0.025 μg/m³, and 0.00031 μg/m³, respectively. Overall, this study is the first nationwide comprehensive assessment of the probabilistic risk of atmospheric PM_2.5-bound toxic metals and provides a theoretical basis for revising and improving China's air quality standards.

In Baja California Sur (BCS), Mexico, the municipality of La Paz has reported higher cancer rates compared to nearby areas, linked to arsenic contamination from abandoned gold mines and naturally high uranium (U) and arsenic (As) levels in sediments. This study evaluates the impact of human activities on natural U and As anomalies in watercourse sediments of the Los Planes watershed and adjacent areas. The geochemical database included 229 analyses from the Mexican Geological Service (SGM 2017) and nine samples analyzed via Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Multivariate statistical and geostatistical methods were used to interpret the data. Using the kriging method for U and the nearest neighbor algorithm for As, spatial models were developed to define the anomalies’ positions and extents. Hierarchical cluster analysis on 85 analyses and 28 parameters identified six clusters representing different influence areas. The study found As concentrations exceeding the Mexican limit of 22 mg/kg for soils in 13 cases, with a maximum of 1520 mg/kg, primarily due to historic gold mine contamination. U concentrations ranged from 0.53 mg/kg to 7.35 mg/kg, within international protection limits, originating from Sierra la Gata’s granites and granodiorites, with potential secondary enrichment in topsoil. The possibility of anthropogenic U impact from phosphatic fertilizers is noted, warranting further investigation.

Fish provide high-quality protein and essential nutrients. However, environmental pollution can lead to the accumulation of toxic substances such as mercury (Hg), with known negative impacts on human consumers. The aim of this study was to assess fish health and potential human health risks by analyzing the presence of nematodes, Hg concentrations, and liver pathology in freshwater fish from La Mojana, Colombia. For this purpose, 326 specimens were collected. Parasitic infection was evaluated using parasitological indices. Total Hg (T-Hg) was quantified using a direct mercury analyzer. Liver pathology was assessed through histopathological examination. Risk-based fish consumption limits were established by calculating the hazard quotient (HQ) and safe consumption limits. The overall prevalence and abundance of nematodes (Contracaecum sp.) were 46% and 2.72 ± 0.47 parasites/fish, respectively. Sternopygus macrurus exhibited the highest prevalence (100%) and parasite abundance (13.5 parasites/fish) during the rainy season, whereas Hoplias malabaricus demonstrated the greatest prevalence (100%) and abundance (14.8 parasites/fish) in the dry season. The average T-Hg was 0.31 ± 0.01 µg/g ww. During the rainy season, S. macrurus had the highest T-Hg levels (0.46 ± 0.08 µg/g ww); in the dry season, Cynopotamus magdalenae showed the highest T-Hg concentration (0.54 ± 0.03 µg/g ww). Significant positive relationships were recorded between T-Hg and parasite abundance, while these were negative with the condition factor. All specimens exhibited hepatic alterations. The HQ and Hg values suggest potential health risks from frequent fish consumption, especially in fish-dependent communities. These findings highlight the need for precautionary measures by health and environmental authorities to safeguard human and ecosystem health.

Although agrochemicals protect crops and reduce losses, these chemicals can migrate to non-target environments via run-off and leaching following irrigation or heavy rainfall, where non-target organisms can be exposed to a mixture of water-soluble compounds. This study investigated whether the water-soluble fractions of selected agricultural soils from South Africa contain quantifiable concentrations of four commonly used pesticides, 2,4-dichlorophenoxyacetic acid (2,4-D), atrazine, dicamba and imidacloprid, and whether the aqueous extracts induce effects in vitro. Effects investigated included cytotoxicity using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] cell viability assay; xenobiotic metabolism using the H4IIE-luc rat hepatoma cell line; and (anti-)androgenic and (anti-)oestrogenic effects were screened for with the human breast carcinoma cell lines MDA-kb2 and T47D-KBluc, respectively. Oxidative stress responses were measured in H4IIE-luc and human duodenum adenocarcinoma (HuTu-80) cells. All extracts of soil induced oxidative stress, while several samples caused moderate to severe cytotoxicity and/or anti-androgenic effects. The herbicide atrazine had the greatest frequency of detection (89%), followed by dicamba (84%), 2,4-D (74%) and imidacloprid (32%). Concentrations of atrazine [2.0 × 10^–1 to 2.1 × 10² ng/g, dry mass (dm)] and the neonicotinoid insecticide, imidacloprid (2.0 × 10¹ to 9.7 × 10¹ ng/g, dm), exceeded international soil quality guidelines. Overall, there was no observable trend between the biological effects and pesticides quantified. Nonetheless, the findings of this study show that agricultural soils in South Africa can elicit effects in vitro and contain quantifiable concentrations of polar pesticides. These agrochemicals might pose risks to the health of humans and the environment, but more assessment is necessary to quantify such potential effects.

This study investigates the contamination of per- and polyfluoroalkyl substances (PFAS) in freshwater fish from waterbodies near former and currently active military bases in the State of New York, USA. Three facilities with a history of long-term use and discharge of aqueous film-forming foam (AFFF) were studied. Here, we focused on previously uninvestigated areas that are outside of the base properties. Freshwater fish samples were collected from sites at different distances both downstream and upstream of the bases. Overall, 508 fish from 25 species were collected at 22 sites over 3 years, and whole-fish PFAS concentrations were quantified using LC–MS/MS. PFAS levels in fish from downstream sites have significantly higher body burden of PFAS. Perfluorooctane sulfonic acid (PFOS), the foaming agent in legacy AFFF, is the dominant PFAS component in fish from downstream sites in all waterbodies sampled and appeared to be the main driving factor differentiating fish from presumed contaminated sites and reference sites. Distance from the contaminant source, species, and hydrological conditions also significantly influenced the PFAS accumulation in fish. Temporal differences were only significant at sites where accidental discharge of AFFF occurred immediately prior to the 1st year of sampling. The current study demonstrates the extent of PFAS contamination and accumulation in biota at a distance away from the contaminant source. We also highlight the need for evaluation of potential concerns for human and ecological health in these areas as a result of historical AFFF use and release from military facilities in the US.

The application of biomarkers is often used to better understand the assessment of the toxicity in aquatic organisms within their natural environment. To this end, we examined the gills and liver of roach (Rutilus rutilus) to measure changes in the activity of the antioxidant enzymes superoxide dismutase, catalase (CAT), glutathione peroxidase, glutathione reductase and the phase II biotransformation enzyme glutathione-S-transferase (GST), as well as changes in the concentration of lipid peroxides (LPOs). Roach were collected at two localities, Veliko Ratno ostrvo and Višnjica (VIS), on the Danube River, where the concentrations of dissolved metals (Cu, Cd, Zn, Fe, Mn, Hg, Ni, As, Pb) in both fish tissues were quantified. This paper describes the integrated reaction of antioxidant enzymes and LPO levels of roach from two sampling localities in the Danube River. Principal component analysis revealed obvious differences of the antioxidant biomarkers investigated between tissues and localities, while integrated biomarker response showed that the liver of the VIS locality had the stronger antioxidant biomarker response. Despite the concordant hypothesized antioxidant induction at the VIS locality in both tissues studied, the effects as a sign of contaminant exposure appear to be mediated in part by suppression of the antioxidant system, with CAT and GST as potential candidate tissue toxicity biomarkers of contaminants.