Bulletin of Environmental Contamination and Toxicology最新文献

In this study, the concentrations of cadmium (Cd), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb) and zinc (Zn) in plants sampled from Mt. Madra were investigated. Furthermore, the distribution characteristics and source identification of potentially toxic metals were investigated with the application of Positive Matrix Factorization (PMF) modelling. Samples of 26 different plant species were taken from Mt. Madra at elevations ranging from 177 to 1347 m using the multi-point sampling approach. The metal quantities measured by ICP-OES are the following sequences (mean ± SD) (mg/kg): Fe (974.96 ± 29.6) > Mn (111.81 ± 2.6) > Zn (27.28 ± 0.2) > Ni (2.17 ± 0.03) > Pb (0.77 ± 0.01) > Cd (0.12 ± 0.01). According to the plant samples in which the highest values were determined, the metals are as follows: Cd (Lathyrus laxiflorus, 0.401 mg/kg), Fe (Ajuga orientalis, 7621.207 mg/kg), Mn (Castanea sativa, 724.927 mg/kg), Ni (Prunella laciniata, 6.947 mg/kg), Pb (Crataegus stevenii, 3.955 mg/kg) and Zn (Prunella laciniata, 50.802 mg/kg). The results of the PMF model showed that Cd had an atmospheric transport factor originated and transported from industrial activites, Ni had a substrate factor, Fe, Mn, Pb and Zn were influenced by different anthropogenic factors.

Chlorpyrifos is widely used across the world as an organophosphate insecticide and frequently contaminates freshwater bodies through runoff from agricultural fields. In the laboratory, static bioassays were undertaken to examine differences in acute toxicity caused by exposure to the technical grade (94% a.i.) and an emulsifiable concentrate (20% EC) of chlorpyrifos to two species of freshwater fish, Labeo rohita and Mystus vittatus. The recovery of actual chlorpyrifos concentrations varied from 83% (technical grade, T) to 89% (emulsifiable concentrate, F) after two hours in water. The susceptibilities of the two fish species to the two types of chlorpyrifos varied. The 96-h LC₅₀ values for T and F chlorpyrifos in L. rohita were 68 and 36 µg/L, respectively, and 120 and 62 µg/L in M. vittatus, respectively. As the exposure period was extended, the LC₅₀ values gradually decreased. LC₅₀ values between the technical grade and formulation were compared following the criteria of Mayer et al. (1986), Schmuck et al. (1994), APHA (1995), and Demetrio et al. (2014). It was concluded from the study that the emulsifiable concentrate (20% EC) of chlorpyrifos was more toxic than technical-grade chlorpyrifos.

The safe management of sewage waste is a current concern due to population growth and waste production. Biosolids, derived from sewage sludge treatment, are globally used as organic fertilizers, aligning with Sustainable Development Goal 6 for resource recycling. However, biosafety concerns arise due to the presence of metals and microplastics in biosolids, potentially impacting soil and water. This study investigated biosolids' use for in vitro cultivation of Bowdichia virgilioides Kunth. Results indicate that while biosolids can replace traditional nutritional media, balancing their concentration is crucial for optimizing plant growth. The WPM (Wood Plat Medium) remains essential for in vitro cultivation, but substituting it with biosolids at concentrations of up to 2 g L^- 1 is feasible, providing similar plant development compared to the WPM medium. However, when combined, there is a complex and challenging interaction between biosolids and the culture medium.

The effects and mechanisms of the different types of biochar on heavy metal passivation are still not fully understood. This study compared the effects of three types of biochar on heavy metal passivation during sludge composting. Compared with composting without biochar, rice husk biochar was most effective for the passivation of Zn and Pb, with increased passivation rates of 1.90% and 20.43%, respectively. In contrast, sludge biochar was the most effective for the passivation of Cr and Hg, with increased passivation rates of 28.30% and 3.09%, respectively. Coconut shell biochar showed the best performance for the passivation of Cu, Ni, As, and Cd, and was enriched with micropore structures, which possibly led to the adsorption and reaction of heavy metals, organic matter, and microorganisms. The improved passivation effect of the rice husk and sludge biochar on heavy metals can be attributed to the improved humification of organic matter. This study suggests that specific types of biochar should be considered for the passivation of different types of heavy metals for practical applications.

Microplastics merit attention as they can be ingested by lower trophic organisms, transferred to the food web, and pose potential risks to higher trophic levels. This study investigated the accumulation and effects of polyethylene microbeads (PEMBs, 63-75 μm) on adult water flea Moina macrocopa (600-800 μm), an order-magnitude difference in size, as a result of acute exposure. The organisms were exposed to PEMBs in four treatments of 0 (the Control), 5, 50, and 500 mg PEMB/L for examining PEMB accumulation, survival and reproduction of the organisms after the 24- and 48-h exposures. In general, M. macrocopa ingested PEMBs within 24-h exposure and reached the cumulative PEMB accumulation value of 0.17 ± 0.21 beads/adult after 48-h exposure in the 500 mg PEMB/L treatment. Exposure to PEMBs resulted in a statistically significant decrease of the cumulative survival rates, from 93 ± 12% in the Control to 37 ± 21% in the 500 mg/L treatment. Nevertheless, exposure to PEMBs did not significantly reduce the cumulative reproduction (p > 0.05), although a decrease was observed. This study suggests that the relatively large-size PEMBs could be ingested by the relatively small-size M. macrocopa and pose potential risks to these organisms.

Considering the environmental impact of triafamone and ethoxysulfuron, it is crucial to investigate their leaching behaviour under different geographical conditions. The present study evaluates the effects of application rate, soil properties and rainfall conditions on leaching of these herbicides and their metabolites. Ethoxysulfuron leached up to 50-60 cm with 82.95 to 89.23% detected in leachates while triafamone leached only to 10-20 cm and was < 0.01 µg mL^-1 in leachates. Highest leachability was observed in loamy sand followed by sandy loam and clay loam soil. M1 metabolite (N-(2-((4,6-dimethoxy-1,3,5-triazin-2-yl) (hydroxy) methyl) -6-fluorophenyl) -1,1-difluoro-N-methyl methane sulfonamide) was majorly present in 0 to 10 cm soil depth. With increase in rainfall, downward mobility of both parent and M1 increased. Amendment of loamy sand soil with farmyard manure reduced the leachability indicating it could mitigate groundwater pollution. However, the effect of different exogenous OM amendments on leaching behaviour of herbicides needs to be evaluated.

PM_2.5, as one of the most harmful pollutant in the atmospheric environment and population health, has received much attention. We monitored PM_2.5 levels at five sampling sites in the Lanzhou City and collected PM_2.5 particles from two representative sites for cytotoxicity experiment. The cytotoxicity of PM_2.5 samples on A549 cells and migration ability of the cells were respectively detected by Cell Counting kit-8 (CCK-8) assay and scratch assay. We detected the levels of cellular inflammatory factors and oxidative damage-related biochemical indexes. RT-qPCR was used to detect the mRNA levels of NF-κB and epithelial-mesenchymal transition (EMT)-related genes. We found that the Lanlian Hotel station had the highest PM_2.5 annual average concentration. The annual average concentration change curve of PM_2.5 showed a roughly "U"-shaped distribution during the whole sampling period. The cytotoxicity experiment showed the viability of A549 cells decreased and the scratch healing rate increased in the 200 and 400 μg/mL PM_2.5-treated groups. We also found 400 μg/mL PM_2.5 induced changes in the mRNA levels of NF-κB and EMT-related genes, the mRNA levels of IKK-α, NIK, and NF-κB in the 400 μg/mL PM_2.5 group were higher than those in the control group. The mRNA levels of E-cadherin decreased and α-SMA increased in the 400 μg/mL PM_2.5 groups, and the mRNA levels of Fibronectin increased in the 400 μg/mL PM_2.5 groups. Moreover, we found hydroxyl radical scavenging ability and T-AOC levels were lower, and LPO levels were higher in the 200 and 400 μg/mL PM_2.5 groups, and the SOD activity of cells in the 400 µg/mL PM_2.5 group decreased. And compared with the control group, the levels of TNF-α were higher in the 200 and 400 μg/mL PM_2.5 groups and the levels of IL-1 were higher in the 400 μg/mL PM_2.5 group. The results indicated that the cytotoxicity of atmospheric PM_2.5 was related to oxidative damage, inflammatory response, NF-κB activity and EMT.

To achieve food security in a contaminated agricultural land, the remediation areas usually need more samples to obtain accurate contamination information and implement appropriate measures. In this study, we propose an optimal encryption sampling design to instead of the detailed survey, which is determined by the variation of heavy metals and the technology capability of remediation, to guide soil sampling for accurately remediation in the potential remediation-effective areas (PRA). The coefficient of screening variation threshold (CSVT), considering spatial variation, technology capacity and acceptable error of sampling, together with the spatial cyclic statistics method of neighbourhood analysis, is introduced to identify and delineate the PRA. Both of the hypothetical analysis and application case studies are conducted to illustrate the advantages and disadvantages of the optimization. The results show that, compared with the detailed survey, the optimal design shows a lower overall accuracy due to its sparsely sampling at the clean area, but it exhibits a similar effect of accurately prediction in boundary delineation and further classification in the PRA in both simulation and application studies. This work provides an effective method for subsequent accurate remediation at the investigation stage and valuable insights into application combination of technology capacity and contaminated agricultural land investigation.

Imazethapyr is the most common herbicide used for weed management in pulses. A field trial was carried out with imazethapyr 10% SL formulation at 100 and 150 g a.i./ha application rates, as pre-and post-emergence, to study dissipation of imazethapyr in soil, persistence in urdbean plant, terminal residues in urdbean grains and effect on soil microbes. An acetate buffered- quick, easy, cheap, effective, rugged, and safe (QuEChERS) method in combination with high-performance liquid chromatography (HPLC) was validated for imazethapyr residue analysis. The half-life of imazethapyr in soil ranged from 15.12 to 18.02 days. The residues of imazethapyr persist up to 60 days in soil and up to 7–15 days in urdbean plant. Residues were not detected in grains at the time of harvest. Persistence of imazethapyr residues in soil significantly impact soil microbial populations depending on herbicide application rates and timing.

The primary objective of the presented research was to assess the impact of intense global economic development, over the last 100 years, on the bioaccumulation of heavy metals in the human body. This evaluation was conducted based on the measurement of heavy metals in human hair samples collected 100 years ago in present-day southern Poland.In this study, concentrations of lead (Pb), cadmium (Cd), arsenic (As), zinc (Zn), copper (Cu), iron (Fe), and selenium (Se) were measured in 61 hair samples,28 of which were obtained from individuals who lived 100 years ago, while the remaining 33 constituted the contemporary control group. The concentrations were determined using a triple quadrupole inductively coupled plasma mass spectrometer (Agilent 8900). Statistical analysis of the obtained results was conducted using the Principal Cmponent Analysis and the non-parametric Mann-Whitney test. In the case of As, Pb, Cd, and Fe, the concentrations were significantly higher in individuals who lived 100 years ago compared to those living today. Over this period, the median concentrations were shown to have decreased by 95%, 94%, 85%, and 69% for As, Pb, Cd, and Fe, respectively. No statistically significant differences were observed for Cu, Zn, and Se. The results obtained for Pb, Cd, As, and Fe unequivocally indicate that the population studied from 100 years ago was more exposed to internal contamination with these metals than people who live nowadays.