Archives of Environmental Contamination and Toxicology最新文献

Tenax extraction, a measure of chemical desorption rates from sediments, was used to evaluate the bioaccessibility of bifenthrin in two different sediments exposed to three temperatures aged over a 56-d holding period. A 24-h single-point Tenax extraction was used and parent ¹⁴C-bifenthrin and polar metabolites were quantified in the sediment and Tenax. Bioaccessibility of bifenthrin was inversely related to the organic carbon (OC) content in the sediment, holding time, and temperature. Sequestration of the bifenthrin into slowly desorbing fractions within the sediment appears to have decreased degradation of the parent compound into metabolites and decreased the amount of parent compound bioaccessible for uptake by the Tenax. These results suggest that the environmental risk of bifenthrin to aquatic species is greatest immediately after the pesticide enters a waterbody after runoff, for low-OC content sediments, and in areas or seasons where water temperatures are colder.

Chemical activation of waste materials, to form activated carbon, (AC) is complicated by the large amounts of chemical activating agents required and wastewater produced. To address these problems, we have developed an optimized process for producing AC, by phosphoric acid activation of construction waste. Waste wood from construction sites was ground and treated with an optimized phosphoric acid digestion and activation that resulted in high surface areas (> 2000 m²/g) and a greater recovery of phosphoric acid. Subsequently the phosphoric acid activated carbon (PAC), was functionalized with iron salts and evaluated for its efficacy on the adsorption of selenite and selenate. Total phosphoric acid recovery was 96.7% for waste wood activated with 25% phosphoric acid at a 1:1 ratio, which is a substantially higher phosphoric acid recovery, than previous literature findings. Post activation impregnation of iron salts resulted in iron(II) species adsorbed to the PAC surface. The iron(II) chloride impregnated AC removed up to 11.41 ± 0.502 mg selenium per g Iron-PAC. Competitive ions such as sulfate and nitrate had little effect on selenium adsorption, however, phosphate concentration did negatively impact the selenium uptake at high phosphate levels. At 250 ppm, approximately 75% of adsorption capacity of both the selenate and the selenite solutions was lost, although selenium was still preferentially adsorbed. Peak adsorption occurred between a pH of 4 and 11, with a complete loss of adsorption at a pH of 13.

²¹⁰Po (polonium), one of the most toxic naturally occurring radionuclides, is well-known as a common natural radionuclide in fish species. Human consumption of ²¹⁰Po-contaminated fish could result in a significant internal dose. This study determined by alpha spectrometry the ²¹⁰Po activity in sixteen selected fish species with different living behaviors (pelagic, demersal), trophic positions (herbivores, carnivores, omnivorous), and masses in Dong Thai Lake, Hanoi, Vietnam. The min, max, and average of the ²¹⁰Po concentration of sixteen fish species were 0.80 ± 0.44, 12.7 ± 0.20, and 3.54 ± 0.31 Bq kg⁻¹, respectively. Regarding the different living behaviors, trophic positions, and masses, the results showed trending of ²¹⁰Po_pelagic > ²¹⁰Po_demersal; ²¹⁰Po_herbivores < ²¹⁰Po_carnivores < ²¹⁰Po_omnivorous and ²¹⁰Po_<0.2 kg > ²¹⁰Po_0.2-1 kg > ²¹⁰Po_>1 kg, respectively. The ²¹⁰Po concentrations in muscle tissue were greater in fish species with a small mass, omnivorous trophic position, and pelagic living behavior relative to demersal fish with a larger mass that were herbivores or carnivores. In addition, the results showed an uneven distribution of ²¹⁰Po activities in atmospheric aerosols, terrestrial soils, surface waters, and lake sediments in the study area. The primary source of ²¹⁰Po could be supplied from atmospheric aerosols and/or terrestrial soils in the study area. The ²¹⁰Po annual effective dose for adults due to fish consumption has been calculated with a range from 20 to 400 µSv y⁻¹ and 111 µSv. y⁻¹ on average, and it is far below the allowable limits of 1000 µSv y⁻¹.

Cadmium-109 whole-body and internal biokinetics were experimentally investigated in critically endangered diamond sturgeon Acipenser gueldenstaedtii after uptake from water or food, in fresh (FW) and brackish (BW; 9‰) salinities typical of the Caspian Sea. Whole-body rates of uptake of ¹⁰⁹Cd from water and subsequent depuration were quantified over 14 and 28 days, respectively. Uptake was greater in FW than BW by a factor of 2.4, but depuration rates were similar in both salinities. In contrast, for the dietary (chironomid) exposure pathway ¹⁰⁹Cd assimilation efficiencies (AEs) were higher in BW (13%) compared to FW (9.5%). Head (including gills) or digestive tract were major repositories of ¹⁰⁹Cd following aqueous and dietary exposures, respectively, including both uptake and depuration phases. The point-of-entry of ¹⁰⁹Cd into the body was also a major and persistent determiner of its subsequent internal distribution. For aqueous exposures, the internal distributions of ¹⁰⁹Cd changed appreciably during depuration with increased activity concentrations in some body components, which again varied with salinity. Increased salinity appreciably enhanced the percentage distributions and activity concentrations of ¹⁰⁹Cd in the liver, kidney and digestive tract, which are typically most pathologically altered by elevated Cd exposure. For dietary exposure, increased salinity also enhanced ¹⁰⁹Cd activity concentrations in most body components. The results repeatedly indicate the important role of salinity in the whole-body and internal biokinetics of ¹⁰⁹Cd in A. gueldenstaedtii, a representative of both a phylogenetically distinct and most endangered family of fishes.

The aim of this work was to study the distribution of relevant inorganic contaminants in environmental samples from Ciudad de la Costa, the second most populated city of Uruguay. For this task aluminum (Al), cadmium (Cd), chromium (Cr), nickel (Ni) and lead (Pb) levels were determined in sand, water, and plant material from six beaches that are located in the area. Analytical methods were successfully validated. Accuracy was ensured by using certified reference materials and spiking procedures. Average metal concentrations in sand and water samples were compared with the maximum limits established by international or national regulations (when available), being far below these limits in all cases. This may indicate that the inorganic contamination in the studied area is rather low, despite the rapid increase in anthropic activities in recent years. To give a deeper characterization of the ecosystem, metal accumulation and mobility within a common plant of the zone, Ammophila arenaria, were studied. Results showed that concentrations in roots were one order of magnitude higher in comparison to aerial parts. In addition, the bioaccumulation coefficient (BAC) showed that the plant accumulates Cd, Cr and Ni, while a low accumulation for Pb was observed. Finally, a Cr(VI) speciation analysis in Ammophila arenaria was performed, showing Cr(VI) percentages below 4.6%, which is relevant from the (eco)toxicological point of view due to the high environmental mobility and bioavailability of this valence state. This work constitutes the first environmental surveillance report of this kind, regarding this populated area of the country.

In this study, representative urban and peri-urban Indian food baskets have been studied for the presence of toxic and essential elements. The concentration of target toxic and essential elements was used to estimate dietary intakes (EDIs) and health risks. Across all food matrices, toxic elements like Cd and Pb were dominant. The highest concentrations of the target elements were found in vegetables, with Cd, Pb, and Ni being beyond permissible limits of the Food and Agriculture Organization of the United Nations and the World Health organization (0.05 mg/kg, 0.1 mg/kg, and 1.5 mg/kg, respectively) in okra, spinach, and cauliflower. The sum of concentrations of the toxic elements (As, Ni, Hg, Cr, Cd, Pb) in vegetables had a range of 0.54–12.08 mg/kg, the highest sum was found in spinach (median 12.08 mg/kg), followed by okra (median 1.68 mg/kg). The EDI was observed for vegetables with a contribution as high as 92% for Cd. Dairy products were found with the highest loading for Ni with a dietary intake of 3.1 mg/kg/day for adults and twice as much for children. Carcinogenic risk for Ni was the highest and found above the threshold for all food categories, as was the case with As. Cumulative carcinogenic and non-carcinogenic risks were mostly contributed by milk and vegetables, in particular, spinach.

Air pollution causes environmental and health problems around the world. In this study, ambient particulate matter with an aerodynamic diameter equal to or less than 10 microns (PM₁₀) has been collected at three different locations in Jeddah city, Saudi Arabia. The locations are characterized by differences in terms of traffic, residential intensity, industrial, and non-road mobile machinery activities. The monthly and annual mass concentration of the PM₁₀ exceeds the recommended annual limit of the World Health Organization (15 µg/m³) and the European air quality standard (40 µg/m³) at the three locations. The collected PM₁₀ samples as well as a certified reference material of atmospheric particulates (NIST 1678a) were digested in aqua regia using microwave digestion. The quantitative elemental analysis was carried out using inductively coupled plasma mass spectrometry. The variations of the elemental concentration in terms of workdays, weekends, seasons, and annual were determined at the three locations. The spatial and temporal elemental variations were found to be different between the three sites, pointing to local influences that should be further evaluated. The concentration of Cd was found to be high and may cause health problems.

Glyphosate is the most widely used herbicide worldwide due to its efficacy in weed control in agriculture. This herbicide has been consistently detected in the aquatic environment, causing harmful consequences to nontarget organisms residing in agricultural regions. In this study, we assessed the effects of environmentally relevant concentrations of glyphosate (30–100 µg/L) on the early life stages of the viviparous fish Jenynsia multidentata through biochemical and locomotor endpoints. At 96 h of exposure, 30 and 65 µg/L glyphosate caused an increase in acetylcholinesterase (AChE) activity, and 65 µg/L glyphosate also augmented the levels of lipid peroxidation. Glyphosate at 100 µg/L did not alter the activity of acetylcholinesterase or the levels of lipid peroxidation, but it stimulated the activity of the cellular detoxification enzyme glutathione S-transferase. In addition, all concentrations affected the swimming of the fish. Under light conditions, glyphosate caused hypolocomotion at all concentrations tested, whereas under dark conditions, this was observed at 30 and 100 µg/L. Hyperlocomotion was observed at 65 µg/L glyphosate. These findings are alarming for the health of fish, such as J. multidentata that inhabit streams that pass through agricultural areas, especially for the early life stages of these fish. Research studying the effects of pollutants on native species is relevant to improve regulation that protects aquatic ecosystems.

Graphical Abstract

Long-term data are required to quantify the impacts of historic industrial pollution and subsequent remedial action on the nearshore benthic community in the St. Lawrence River Area of Concern at Cornwall, Ontario. Specifically, high-quality temporal records are needed to understand changes in benthic invertebrate assemblages in response to multiple possible drivers including industrial pollution, environmental heterogeneity, and climate warming. We compare long-term records of subfossil chironomid assemblages and geochemical variables among sediment cores from two Cornwall sites with differing pollution histories and a minimally disturbed downstream reference site. Chironomids were functionally absent from the Cornwall sediment cores when mercury and zinc concentrations were elevated. As metal concentrations decreased in more recent sediment intervals, chironomid abundance and the relative abundance of pollution-sensitive taxa increased. Recently deposited sediment in all three sediment cores display increased relative abundance of warm-water, macrophyte-associated taxa. We conclude that these temporal changes in chironomid assemblages provide evidence for ecological recovery for both of the impacted sites, consistent with the objectives of the current management strategy. These findings advance our understanding of industrial impacts on fluvial chironomid ecology, directly inform local management strategies, and further develop the application of chironomids as bioindicators for contaminated sediments.