Toxics最新文献

Cadmium (Cd) is a typical pollutant with strong toxicity even at low concentrations. In the marine environment, Cd is a problem of magnitude and ecological significance due to its high toxicity and accumulation in living organisms. The clam Meretrix meretrix is a useful bioindicator species for evaluating heavy-metal stress. This study investigated the extent of recovery from Cd²⁺-induced oxidative and immune impairments in M. meretrix gills achieved by short-term depuration. Clams were exposed to 3 mg/L Cd²⁺ for six days or three days followed by three days of depuration, and the Cd contents, morphological structure, osmoregulation, oxidative stress, and immune responses in the gills were evaluated. The results showed that gill Cd contents increased with exposure, reaching 9.857 ± 0.074 mg·kg^-1 on day 3 but decreased slightly to 8.294 ± 0.056 mg·kg^-1 after depuration, while reaching 18.665 ± 0.040 mg·kg^-1 on day 6 after continuous exposure. Histological lesions, including lamellar fusion, hemolymphatic sinus dilation, and ciliary degeneration, partially recovered after depuration. Reactive oxygen species (ROS) and malondialdehyde (MDA) levels decreased significantly, while DNA-protein crosslinking rate (DPC) and protein carbonyl (PCO) showed minor reductions. Total antioxidant capacity (T-AOC) and the activities of Ca²⁺/Mg²⁺-ATPase (CMA), cytochrome c oxidase (COX), succinate dehydrogenase (SDH), and lactate dehydrogenase (LDH) increased by over 10% during depuration, though these changes were not statistically significant. Lysozyme (LZM) activity and MT transcript levels increased progressively with Cd exposure, indicating their suitability as biomarkers of Cd stress. Acid and alkaline phosphatase (ACP, AKP) activities and Hsp70 and Nrf2 mRNA transcripts exhibited inverted U-shaped response consistent with hormetic response. ACP and AKP activity levels rose by more than 20% after depuration, suggesting partial restoration of immune capacity. Overall, Cd exposure induced oxidative damage, metabolic disruption, and immune suppression in M. meretrix gills, yet short-term depuration allowed partial recovery. These findings enhance understanding of Cd toxicity and reversibility in marine bivalves and reinforce the usage of biochemical and molecular markers for monitoring Cd contamination and assessing depuration efficiency in aquaculture environments.

The multiple sources and concomitant negative environmental and health impacts of volatile organic compounds (VOCs) in the atmosphere demonstrate their importance in air pollution control. This study employed environment- and health risk-oriented source apportionment methods to quantitatively estimate VOCs' contribution to air pollution and health risks, using offline VOC measurements from the Harbin urban region from 2021 to 2022. Total volatile organic compounds (TVOCs) averaged 25.6 ± 8.2 ppb, except for alkanes (34.4%), and aromatics (24.2%) were found to be a major contributor, with the highest L_OH (38.0%), ozone formation potential (OFP) (43.0%), and secondary organic aerosol formation potential (SOAFP) (95.0%) and exerting a directly toxic effect (46.0%). Positive matrix factorization (PMF) source apportionment revealed that vehicle exhausts, combustion sources, solvent and coating usage, solvent and fuel evaporation, and petrochemical industry sources were key VOC sources. A health risk assessment showed that there was an integrated carcinogenic risk of 5.8 × 10^-4, with respiratory (1.5 × 10^-4) and hematologic systems (1.5 × 10^-4) representing higher carcinogenic risks. Both benzene and naphthalene exhibited carcinogenic risks of 1.5 × 10^-4, implying an excess of higher cancer risk levels (1.0 × 10^-4). Significant joint environmental and health benefits could be obtained by reducing benzene and naphthalene concentrations by about 50.0%, along with the abatement of vehicle exhausts (82.6%), combustion sources (40.7%), and solvent and coating usage (50.7%). This study can serve as useful guidance for the quantitative mitigation of hazardous VOCs and their key sources.

With the acceleration of urbanization in China, air pollution is becoming increasingly serious, especially PM_2.5 pollution, which poses a significant threat to public health. The study employed different deep learning models, including recurrent neural network (RNN), artificial neural network (ANN), convolutional Neural Network (CNN), bidirectional Long Short-Term Memory (BiLSTM), Transformer, and novel hybrid interpretable CNN-BiLSTM-Transformer architectures for forecasting daily PM_2.5 concentrations on the integrated dataset. The dataset of meteorological factors and atmospheric pollutants in Qingdao City was used as input features for the model. Among the models tested, the hybrid CNN-BiLSTM-Transformer model achieved the highest prediction accuracy by extracting local features, capturing temporal dependencies in both directions, and enhancing global pattern and key information, with low root Mean Square Error (RMSE) (5.4236 μg/m³), low mean absolute error (MAE) (4.0220 μg/m³), low mean absolute percentage error (MAPE) (22.7791%) and high correlation coefficient (R) (0.9743) values. Shapley additive explanations (SHAP) analysis further revealed that PM₁₀, CO, mean atmospheric temperature, O_3, and SO₂ are the key influencing factors of PM_2.5. This study provides a more comprehensive and multidimensional approach for predicting air pollution, and valuable insights for people's health and policy makers.

Pharmaceuticals are increasingly recognized as contaminants of emerging concern, yet monitoring strategies often do not reflect actual consumption patterns or ecological risk. Greece presents a particularly relevant case due to high pharmaceutical use and fragmented monitoring data. In the present study, 359 pharmaceuticals, metabolites, and transformation products were reviewed, as reported in monitoring studies in Greek wastewater, surface waters, and drinking water. Consumption data (from the Organization for Economic Co-operation and Development, OECD), environmental occurrence (from 55 studies), and ecotoxicity thresholds (i.e., from the NORMAN Database) were integrated to calculate risk quotients (RQs) and assess monitoring gaps. RQ values were derived for 241 compounds: 38 (16%) high-risk, 60 (25%) medium-risk, and 143 (59%) low-risk. High-risk substances included several NSAIDs, macrolide and fluoroquinolone antibiotics, synthetic hormones, contrast agents, and triclosan. Major under-monitoring was observed for widely consumed classes A and B, while antibiotics, NSAIDs, antidepressants, and analgesics were disproportionately targeted. Several metabolites showed higher RQs than their parent compounds but were rarely analyzed. These findings reveal significant mismatches between pharmaceutical use, environmental occurrence, and ecological risk in Greece. Results support adopting risk-based prioritization for environmental monitoring and align with ongoing updates to EU water policy.

This study estimates the levels of chemical contamination and the responses of biochemical and cytogenetic biomarkers in Unio pictorum from the Nemunas River after a large-scale fire at a tire storage and processing warehouse (in October 2019), as well as after the subsequent discharge of partially cleaned water used for firefighting. The impact of firefighting water (FW) on the River Nemunas ecosystem was assessed. Elevated levels of trace metals (Pb, Cu, Co, Cr, Al, Zn) in U. pictorum mussels collected downstream from the wastewater treatment plant (WTP) discharger were measured in the first year after the accident. Genotoxic aberrations in gill cells were significantly more frequent in mussels collected downstream of the WTP discharger, along with higher frequencies of cytotoxic damage and changes in acetylcholinesterase activity. PAH metabolite concentrations, including naphthalene (Nap) and benzo(a)pyrene (B(α)P), were also elevated in haemolymph in U. pictorum gathered downstream from the discharger, but differences were not statistically significant. The total sum of 16 PAH concentrations in mussels collected in 2021 and 2022 was over 5 times higher than those in 2020, and the profile of accumulated metals shifted, with Ni, Cd, Cr, and Pb concentrations decreasing while Zn increased significantly. Mussel haemolymph in 2021 contained the highest levels of B(α)P-type PAH metabolites, indicating increased oxidative stress and neurotoxic impact. The results of chemical analysis and the values of genotoxic aberrations determined in gill cells of U. pictorum collected in 2021 and 2022 indicate an increase in PAH contamination and geno-cytotoxic impact compared to the results of 2020; these changes might be related to the gradual cancellation of COVID-19 restrictions and restoration of routine activities. The study provided an opportunity to demonstrate the unique response of a less anthropogenically stressed ecosystem to the extreme impact of contamination related to the fire on the tire recycling plant.

This study systematically analyzed commercially available traditional Chinese medicines for As, Hg, Pb, Cd, and Cu, classifying them into roots and rhizomes (underground parts), stems and leaves, whole herbs, flowers, fruits and seeds (aboveground parts), and animal-derived decoction pieces. The concentration ranges of five elements in underground parts were 0~7.09, 0~0.29, 0~4.1, 0~1.1 and 0~49.2 mg/kg, with exceedance rates of 0-2.3%. Aboveground parts showed ranges of 0~1.54, 0~1.02, 0~13, 0~0.96 and 0~43.4 mg/kg, with exceedance rates of 0-8.8%. Animal-derived decoction pieces showed ranges of 0.07~27.18, 0~1, 0~55, 0~4.11 and 0.23~43.9 mg/kg, with exceedance rates of 6.7-41.3%. Principal component and cluster analyses indicated distinct contamination sources between animal-derived and plant-derived materials. The pollution index showed that animal-derived materials required special attention. Among plant-derived materials, Notoginseng Radix et Rhizoma, and Artemisiae Argyi Folium were also of concern. Health risk assessment indicated low non-carcinogenic risks across all categories (HI < 1), and uncertainty analysis showed a 0% probability of HI > 1. The 95th percentile carcinogenic risk for all categories was <1 × 10^-4. Sensitivity analysis identified metal concentrations and daily intake as key uncertainty contributors. The findings underscore distinct contamination patterns between material types, highlighting the need for targeted control strategies, including strengthened source management and standardized dosing.

Metronidazole (MTZ), a widely used antiamoebic and antibacterial drug, has been linked to male reproductive damage. The aim of this study was to investigate Olea europaea L. and Equisetum arvense L. ethanol extracts for the protection against testicular toxicity and male infertility caused by MTZ, and to characterize the underlying mechanisms. Forty-two male rats were divided into six groups. The animals in group 1 served as the controls and received a daily oral dose (1 mL) of the vehicle. The animals in group 2 received metronidazole at doses of 400 mg/kg. Group 3 was treated with E. arvense extract at doses of 100 mg/kg. Group 4 was treated with O. europaea leaf extract at doses of 400 mg/kg. Group 5 was treated with metronidazole and E. arvense extract at doses of 400 and 100 mg/kg, respectively. Group 6 was treated with metronidazole with O. europaea leaf extract at doses of 400 and 400 mg/kg, respectively. The rats were given a daily oral dose of different treatments for 60 days, after which the animals were euthanized to study the histopathological and molecular changes in the testis and the sperm count in the epididymis. The testosterone levels, MDA levels, and GSH contents were also assessed in the rats in all groups. The findings revealed that the MTZ treatment caused a substantial increase in MDA levels and upregulated the NBN gene expression relative to the control. Moreover, the MTZ treatment produced significant reductions in the sperm count and viability, testosterone levels, and GSH content, and downregulated the INSL-3, STAR, HSD-3β, and CYP11A1 gene expression compared to the control. The adverse effects in testicular tissue were significantly reduced in rats given the O. europaea leaves and E. arvense treatment. The findings may show that MTZ can enhance testicular toxicity and infertility, but both plant extracts can prevent these harmful consequences.

Aquaculture systems face escalating ecological risks due to the widespread use and persistence of antibiotics, which disrupt microbial-mediated nitrogen cycling and exacerbate greenhouse gas (GHG) emissions. This review synthesizes the recent research on how common antibiotics, such as sulfonamides, quinolones, tetracyclines, and macrolides, with the concentration ranging from μg/L to mg/L, alter microbial community structure, functional gene expression (e.g., amoA, nirK, and nosZ), and key nitrogen transformation processes. These disruptions inhibit nitrogen-removal efficiency by 25-55%, promote the accumulation of toxic intermediates (e.g., NH₄⁺ and NO₂^-), and enhance emissions of potent GHGs of nitrous oxide (N₂O) and methane (CH₄). The effects are influenced by antibiotic type; concentration; environmental conditions; and interactions with co-contaminants such as heavy metals (Cu²⁺ and Pb²⁺ at 50-200 μg/L) and microplastics (0.1-10 mg/L), which can synergistically amplify ecological risks by 20-40%. The research in this field has largely focused on the toxicity of individual antibiotics, so significant gaps remain regarding combined pollution effects, long-term microbial adaptation, and molecular-scale mechanisms. This review synthesizes research on the impacts of aquaculture antibiotics on microbial nitrogen cycling and GHG emissions, identifying key mechanisms and research gaps. Its significance lies in laying a scientific foundation for integrated antibiotics pollution control strategies and bridging basic research with practical aquaculture management to advance the sustainability of aquaculture ecosystems.

Atrazine (ATZ), a typical triazine herbicide with a long half-life and recalcitrant biodegradation, contaminates water and soil, necessitating efficient removal technologies. Conventional adsorbents have limited capacity and stability, while sesame straw-derived biochar realizes agricultural waste recycling and provides an efficient, economical, and eco-friendly adsorbent. Sepiolite, a natural mineral with a unique fibrous structure and a high specific surface area, has attracted widespread attention. Therefore, in this work, the agricultural waste of sesame hulls and sepiolite were used as precursors to prepare a composite material of sesame hull biochar/sepiolite (KNPB) through co-mixing heat treatment, followed by sodium hydroxide activation and pyrolysis. The results showed that, under the conditions of an adsorbent dosage of 3 g/L, pH of 6.8, and an adsorption time of 360 min, the removal rate of 3 mg/L ATZ by KNPB was 89.14%. Reusability experiments further demonstrated that KNPB has the potential for practical application in water treatment. Additionally, by integrating adsorption kinetics and isotherm analysis with a suite of characterization results from BET, FTIR, and XPS, the adsorption mechanism of KNPB for ATZ was further clarified to be primarily based on pore-filling, π-π interactions, and hydrogen bonding. This study not only provides a new idea for the resource utilization of waste sesame straw, but also provides scientific guidance for the solution of atrazine pollution, which has important environmental and economic significance.

The uptake and accumulation of heavy metals by wild-grown mushrooms is raising health concerns for consumers worldwide with respect to variability conditioned by species and harvesting site specificity. This study aims to evaluate the concentration of elements (Zn) and heavy metals (Cd, Pb, Hg) in wild-growing edible mushroom samples (n = 200) collected from industrial and non-industrial areas in Poland. Over half of the analyzed mushroom samples (51%) exceeded EU limits for Cd, Pb, or Hg. Xerocomellus chrysenteron and X. subtomentosus (XCS) showed the highest accumulation, with median Cd and Pb concentrations of 3.53 mg/kg and 0.63 mg/kg fresh mass, respectively, in industrial areas. Spatial factors, including distance from emission sources and wind direction, significantly influenced element accumulation, with Cd levels in XCS up to 20 times higher than in Suillus species. A high-consumption scenario (96 g/day) indicated a substantial non-carcinogenic risk (HQ > 1) from Cd exposure via XCS consumption, both in industrial (HQ up to 9.01) and non-industrial areas (HQ max = 1.80), with cumulative hazard index (HI) ranging from 1.21 to 11.01. It is imperative to select the optimal regions for mushroom harvesting and to refrain from consuming species that accumulate elements to the greatest extent.