Bulletin of Environmental Contamination and Toxicology最新文献

Elevated atmospheric ammonia (NH₃) concentrations have been reported in the Athabasca Oil Sands Region of Alberta, although the source of these emissions is uncertain. We compiled monthly atmospheric NH₃ data obtained by passive samplers at 45 sites over a 4-year period and found that NH₃ concentrations were greatly elevated above background levels in the summer and were positively correlated with air temperature at sites close (< 15 km, n = 16) as well as at sites distant (> 15 km, n = 29) from the center of industrial activities. Natural surface waters in the region have not been previously considered as potential NH₃ sources even though the region is dominated by wetlands and small lakes. Measurements of 66 of these lakes showed that 30% have a pH > 8.0 with 3% having a pH > 9.0 that are expected to contain appreciable amounts of NH₃ that can be released to the atmosphere under summertime conditions. Further, most lakes are less than 3 m deep and total Kjeldahl N could be as high as 3.5 mg L^-1 in shallow lakes and the temperature of the lakes can exceed 20 °C in summer, promoting organic matter mineralization and the production of NH₄⁺. We suggest that these conditions can promote the release of NH₃ from natural waterbodies as well as tailings ponds in the summertime and explain the spatial patterns in atmospheric NH₃ that are observed regionally. These emissions need to be better characterized in further studies.

Microplastics and heavy metals are ubiquitous pollutants in marine ecosystems, and their combined effects pose a risk to aquatic life and potentially to humans. In this study, microplastics and heavy metals were investigated in different organs of three bivalve species (Crassostrea ariakensis, Mactra veneriformis and Sinonovacula constricta) from the South Yellow Sea. The mean abundance of bivalves microplastics was 8.97 ± 4.63 items/individual, 3.53 ± 2.13 items/g wet weight. Transparent-coloured fibrous small-sized microplastics were the dominant type. PA is the primary polymer component. The heavy metals were more contaminated with Zn, but there is no statistically significant correlation between microplastics and heavy metals. Overall, this study indicates that both microplastics and heavy metals are present in all three species. These findings emphasize the urgent need for immediate attention to environmental monitoring and public health intervention measures to address the growing threat of heavy metals and microplastics.

This study evaluated the effects of atrazine, benzo [a]pyrene, and carbendazim on common carp (Cyprinus carpio). Fish were exposed to nominal concentrations of 5, 15, 25, and 45 ppb (prepared from 5 ppm stock solutions), with HPLC analysis confirming actual levels of 4.90, 14.70, 24.50, and 44.10 ppb (98% recovery) over exposure periods of 5, 15, and 30 days. Genotoxicity was assessed using the comet assay to detect DNA strand breaks and the micronucleus assay to evaluate chromosomal alterations. Blood smears stained with giemsa were examined for red blood cell and nuclear abnormalities. Histopathological changes were analyzed following standard formalin fixation, paraffin embedding, and hematoxylin-eosin staining. Peak DNA damage occurred after 5 days of exposure to 15 ppb benzo[a]pyrene and carbendazim and 25 ppb atrazine (P = 0.001). Both genotoxicity assays revealed concentration and time dependent effects. The micronucleus assay further showed significant increases in chromosomal damage, supported by red blood cell distortions and nuclear abnormalities. Histopathological observations confirmed pronounced tissue alterations, with atrazine producing the most severe toxic effects at equivalent concentrations. Overall, both dose and duration influenced the severity of genotoxic and histopathological impacts, identifying atrazine as the most potent toxicant.

Chelem is a karstic lagoon with urban settlements, economic activities, and environmental services, making it highly vulnerable to metal contamination. This study evaluated metal sediment contamination using enrichment factor, geoaccumulation index and ecological risk index across dry, rainy and Nortes seasons. Cadmium and arsenic concentrations exceed the SQuiRTs thresholds for early biota damage. Metal distribution was driven by submerged groundwater discharges, co-transport with fine particular matter in rainy and Nortes seasons, and direct inputs from urban wastewater and port operations. Cadmium, arsenic and tin exhibited minor to moderate enriched levels. Geoaccumulation index classified the lagoon from minor to highly contaminated. Despite this, the overall ecological risk index remained low. However, sediment-bound metals may already affect local biota and pose future risks to fisheries and human health. These findings highlight the need for continued monitoring and improved management to prevent long-terms ecological and public health impacts in this vulnerable karstic system.

Benzophenone-type ultraviolet filters are widely used as ultraviolet (UV) light filters in a large number of commercial products. However, knowledge of their occurrence in indoor environments is still limited. Herein, the concentrations and distribution profiles of five benzophenones, including 2,4-dihydroxybenzophenone (BP-1), 2,2',4,4'-tetrahydroxybenzophenone (BP-2), 2-hydroxy-4-methoxybenzophenone (BP-3), 2,2'-dihydroxy-4-methoxybenzophenone (BP-8), and 4-hydroxybenzophenone (4-OH-BP), were surveyed in indoor dust samples from households (n = 27) and university dormitories (n = 23) in Nanjing, China. The concentrations of the sum of five benzophenones (ΣBPs) ranged from 0.8 to 284.4 ng/g and 1.3 to 70.7 ng/g in dust from households and dormitories, respectively. The median value of individual benzophenone concentrations was found in dormitory dust samples were generally higher than those in house dust samples. Among five benzophenones analytes, BP-1, BP-3, and 4-OH-BP were three major benzophenones in dust from two microenvironments, respectively accounting for 97.5% (house) and 98.3% (dormitory) of the ΣBPs concentrations. The estimated daily intakes (EDI_total) of ΣBPs for different age groups via indoor dust, based on median concentrations analyzed, showed that infants were the most vulnerable population, with EDI_total (0.052 ng/kg.bw/day) of 1.3-8.6 folds higher than that of the other age groups. Moreover, the median EDI_total values (0.021-0.025 ng/kg.bw/day) for students who reside in dormitories were higher than adults (0.009-0.01 ng/kg.bw/day) who reside in the house, indicating that more attention should be given to the special exposure population, such as infants and students.

Petroleum refining is a high-risk process with significant potential for soil contamination. In this study, we applied Geodetector software to identify the spatial drivers of six contaminants of concern (COC): vinyl chloride (VC), 1,2,3-trichloropropane (TCP), benzo(a)pyrene (BaP), naphthalene (NAP), dibenzo(a,h)anthracene (DBA), and petroleum hydrocarbons (C10-C40) at a representative refinery in China. Soil sampling (n = 496) revealed distinct vertical distributions: VC/TCP penetrated deeper aquifers (1.5 m) than did polycyclic aromatic hydrocarbons (PAHs) (BaP/DBA < 1.0 m). Geographic detector (GD) analysis revealed significant drivers (q > 0.1, p < 0.05) and showed that storage tanks emerged as the dominant driver for VC (q = 0.182), BaP (q = 0.369), NAP (q = 0.653), and C10-C40 (q = 0.680) distributions, while process units predominantly governed DBA (q = 0.389) dispersion. Notably, TCP exhibited no significant association with the assessed factors. Factor interaction analysis revealed synergistic effects between wastewater facilities and storage zones (qmax = 0.912). This study provides critical insights to guide the remediation of retired refineries and implement precision prevention strategies in active facilities across China, while offering a reference for soil environmental management in refineries worldwide.

China faces escalating ozone pollution challenges, with O₃ becoming the primary pollutant in summer since 2013 and exhibiting deteriorating compliance rates (Grade I attainment plummeted from 6.9 to 0.3% during 2015-2023). Critical hotspots include the Beijing-Tianjin-Hebei region (exceeding standards by 20 µg/m³), driven by inadequate coordinated control of VOC and NO_x. Analysis of the ABaCAS-EI v2.0 dataset (2005-2021) reveals divergent precursor trends: VOC emissions shifted from residential to industrial dominance, with industrial solvents (PRSO) surging 389% during 2005-2013 and comprising 61% of national totals by 2021. Spatially, eastern provinces (e.g., Guangdong) showed transport-industrial emission profiles (TRON: 28%; PRSO: 32%), while northern regions achieved significant NO_x reductions through industrial restructuring, with Hebei's emissions falling 46% from peak levels. Conversely, NO_x emissions peaked earlier (2011), but transportation's share grew to 42% by 2021 (TRON: 31%). Regional disparities persist-coastal areas leveraged advanced controls, whereas western provinces struggled with expanding pollution bases. These findings underscore the imperative for spatially-explicit strategies addressing sector-region heterogeneities to mitigate ozone's health/ecological impacts.

The acute toxicities of para-phenylenediamine quinones (PPDQs) to salmonids at the whole-organism level remain unclear. Therefore, in this study, we investigated the acute toxicities of three PPDQs, 6PPDQ, 7PPDQ, and 8PPDQ in coho salmon (Oncorhynchus kisutch) juveniles and embryonic cells (CSE-119) using 24-h acute toxicity tests and cytotoxicity assays. The 24-h 50% effect concentration values of 6PPDQ and 7PPDQ for the juveniles were 41.5 ng/L (95% confidence interval: 21.6-61.4) and 5.39 μg/L (2.26-8.53), respectively, while 8PPDQ did not affect mortality at the tested concentration (60.6 μg/L). Further, the 24-h 50% effect concentration value of 6PPDQ for CSE-119 was 14.9 μg/L (13.0-16.7), but 7PPDQ and 8PPDQ did not sufficiently reduce CSE-119 cell viability even at concentration up to 500 μg/L, indicating marked differences in toxicity among the compounds. These findings indicate that, at both the whole-organism and cellular levels, 6PPDQ exhibited the highest toxicity among the three PPDQs, likely due to differences in chemical structure.

This study investigated the bioaccumulation of Zn, Pb, and Cd in the sternal feathers of house sparrows (Passer domesticus) collected from five sites in Meknes, Morocco, representing urban, industrial, and rural environments. Metal concentrations were quantified using inductively coupled plasma optical emission spectrometry (ICP-OES). The analysis revealed significant spatial differences for Pb and Cd, whereas Zn showed no marked variation among sites. Post-hoc comparisons confirmed that urban and industrial stations had considerably higher Pb and Cd levels compared to the rural reference site. No significant sex-related differences were found. Principal Component Analysis (PCA) was used as a descriptive tool to visualize correlations among metals and sampling sites, confirming spatial clustering linked to anthropogenic influence. These findings highlight P. domesticus as a reliable and non-invasive bioindicator of urban and industrial metal pollution, particularly for Pb and Cd, emphasizing its ecological relevance in monitoring environmental contamination.