In this study, a coupled Weather Research and Forecasting-Community Multiscale Air Quality (WRF-CMAQ) model was developed to analyze the atmospheric transport of polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) in the megacity of Shanghai, and the population’s exposure to them. The results showed that 69.88% of the simulated values are within 0.5 to 2 times the observed values, indicating good accuracy. In 2019, the highest PCDD/Fs pollution levels in Shanghai’s atmosphere were observed in winter, followed by fall and spring. The lowest levels occurred in summer, with respective mass concentrations of 847.08, 629.53, 588.38, and 406.96 fg/m3 and respective TEQ concentrations of 59.29, 44.46, 40.80, and 28.08 fg I-TEQ/m3. The areas most polluted with atmospheric PCDD/Fs were Yangzi, Yangzhou, and Shanghai. Fs were found in Yangpu, Hongkou, Huangpu, Jing'an, Baoshan, Jinshan, and Songjiang. The respiratory exposure of Shanghai residents to PCDD/Fs followed the trend of adolescents > elderly > middle-aged people, with 10.67, 8.86, and 8.47 fg I-TEQ/(kg·d), and the risk of exposure was within the acceptable range. The contribution of local emission sources is much larger than that of foreign emission sources, indicating that local industrial production processes and combustion activities mainly cause atmospheric PCDD/Fs pollution in Shanghai.
As the ultimate destination of antibiotics in rivers, the mechanism and change law of migration from rivers to oceans have not been fully and systematically studied. In this study, surface water samples were collected in the Yangtze River Estuary and its offshore areas in the wet season and dry season of 2023. Solid-phase extraction and high performance liquid chromatography-mass spectrometry were used to identify 20 antibiotics in five categories. This analysis was conducted to assess the concentrations, temporal and spatial distribution, and potential ecological risks. The results showed that the concentrations of 20 antibiotics ranged from not detected ~ 63.32 ng·L–1, and showed a decreasing trend from inland to marine areas from the mouth-adjacent section (average 108 ng·L–1) to the estuary section (average 50 ng·L–1), to the coastal section outside the mouth (average 40 ng·L–1), and the coastal area (average 29 ng·L–1). The concentrations of the five types of antibiotics from high to low were chloramphenicols > macrolides > sulfonamides > quinolones > tetracyclines. The categories and amount of detected antibiotics showed significant seasonal differences. The seasonal-change pattern showed that the ML concentration season was significantly higher in the dry than the wet season, while the concentrations of TCs were significantly higher in the wet season than the dry season. Antibiotics, such as Sulfamethoxazole, Ciprofloxacin, Chlortetracycline, Erythromycin, Chloramphenicol, Ofloxacin, posed a significant threat to the water in the study area, and the ecological risks should not be overlooked.
This article provides a review of the impacts and potential ecological risks of antibiotics and resistance genes in livestock and poultry farming environments. Through systematic research on the relevant literature, the use of antibiotics in livestock and poultry farming in different regions was summarized. The study found that the residual concentrations of antibiotics and resistance genes in soil after returning livestock and poultry manure to the field varied due to factors such as manure type, region, farm scale, and management measures. Moreover, the migration and transformation of antibiotics and resistance genes in soil are influenced by the soil type and fertilization methods. This study specifically explored the impact of the spreading of resistance genes through mechanisms such as horizontal gene diffusion by soil microorganisms and systematically elucidated the ecological risks of antibiotics and resistance genes. Finally, based on the current pollution situation of returning livestock manure to the field, a summary and outlook on reducing the accumulation and diffusion of antibiotics and resistance genes in the environment were prepared. The work is expected to provide strong support for a comprehensive understanding of the environmental impacts and ecological risks of antibiotics and resistance genes in livestock and poultry farming.
The contents of halogenated flame retardants (HFRs) in 31 surface soil samples collected from different areas of Hefei City were measured by gas chromatography-mass spectrometry. Their composition characteristics, spatial distribution, and sources were explored. The results showed that the mean concentrations of ∑23PBDEs, ∑22ABFRs, and ∑11DECs in the surface soils of Hefei City were (6.490 ± 13.221), (26.375 ± 101.928), and (0.815 ± 0.760) ng/g, respectively. DBDPE is the main homologue among alternative flame retardants, accounting for 84.4%. In terms of spatial distribution, the hotspots of HFRs were mostly located in manufacturing concentrated areas, such as urban development zones and high-tech zones. Source analysis revealed that the use of commercial polybrominated diphenyl ethers and alternative flame retardants in the study area were the main emission sources, followed by the production, transportation, and environmental degradation process of HFRs. Non-carcinogenic risk assessment was carried out based on hazard index method. The results showed that the non-carcinogenic risk index of the target objects in the study area were less than 1, which were within the acceptable range, indicating that there was no non-carcinogenic risk.
The spatial distribution characteristics and potential health risks of hexabromocyclododecane (HBCD) in 34 farmland soils in Shanghai were investigated using the variance analysis and hazard quotient (HQ) methods. Three HBCD homologs (α-, β- and γ-HBCD) were detected in all samples. The total concentration of HBCD (∑HBCDs) ranged from 0.30 to 25.4 ng/g, with an average value of 1.78 ng/g. The ∑HBCDs in agricultural soils exhibited significant spatial variation, of which Baoshan District and Jiading District had notably higher average ∑HBCDs compared to other areas (p < 0.05). It was concluded that HBCDs mainly originated from the combined influence of industrial and vehicular emissions. The proportions of α-, β- and γ-HBCD in Shanghai agricultural soils were 2.90% ~ 73.4%, 5.23% ~ 63.8%, and 6.95% ~ 85.5%, respectively. The proportion of γ-HBCD was lower in 91.2% of the sampling sites than in commercial products, indicating the presence of isomeric interconversion. Daily exposure to ∑HBCDs, combining oral and dermal ingestion, ranged from 3.17 × 10–4 to 1.57 × 10–1 ng/(kg·d), peaking in infants. Oral ingestion contributed more to daily exposure than dermal contact across age groups. The HQs indicated that the current HBCD concentrations posed a minimal risk to all populations.
Rivers serve as the primary corridors for transporting plastics to the sea. To understand the sources, pathways, and fate of plastic pollution, this paper provides an inductive analysis and computational optimization of plastic flux into rivers. Additionally, given the limited research on ultraviolet (UV) absorbers in plastics and the absence of quantitative data on UV absorbers leaching from plastics into rivers, this paper synthesizes and refines methods for calculating plastic riverine fluxes. It also proposes an equation for estimating the transport flux of UV absorbers through river systems. The results showed that the Rhine River in Europe has the highest mass flux of total plastics (including both microplastics and macroplastics), followed by the Ganges River in India. Among the five commonly studied types of UV absorbers, benzotriazole UV absorbers (213.40 kg/a) and benzophenone UV absorbers (192.95 kg/a) exhibited the highest riverine fluxes. Predictions based on a biotoxicity model indicated that benzotriazoles have significant potential biotoxicity, highlighting the need for further studies on their environmental behavior, fate, and ecological impacts. This paper aims to summarize and analyze global plastic associated UV absorbers fluxes into rivers, providing a foundation for developing effective prevention and control strategies to address UV absorber pollution and protect aquatic ecosystem health.
中国综合性科技类核心期刊(北大核心)
