Dissolved polycyclic aromatic hydrocarbons (PAHs-d) in response to hydrology variation and anthropogenic activities in the Yangtze River, China

Long-term effects of emission reduction measures on PM2.5 sources and children's lung function in Jinan, China

Many studies have reported the damaging effect of PM2.5 on the lung function of school-age children, but the potential impact of different PM2.5 sources remains unclear. This study analyzed the composition of PM2.5 at a sampling site in Jinan City between 2014 and 2020. Coinciding with the implementation of the environmental protection policies in Jinan, the study time was segmented into three distinct periods. PM2.5 and its components (such as metals and polycyclic aromatic hydrocarbons) gradually decreased across these periods. The results of the Positive Matrix Factorization (PMF) showed that the concentrations of PM2.5 were reduced to varying degrees for different sources. The generalized linear model, after adjustment, found that increased industrial emissions were associated with decreased FVC (OR: 0.92, 95%CI: 0.87-0.98) and FEV1 (OR: 0.91, 95%CI: 0.86-0.96) in girls during Period 1. In Period 2, biomass burning and road dust were associated with a decrease in FVC (OR: 0.91, 95%CI: 0.84-0.99) and FEV1 (OR 0.92, 95%CI: 0.85-0.99) for boys, and in the same period, the reductions in FVC (OR: 0.90, 95%CI: 0.83-0.97), FEV1 (OR: 0.91, 95%CI: 0.85-0.97) and PEF (OR: 0.77, 95% CI: 0.68-0.90) in girls were associated with gasoline combustion. No source was found to be associated with a decrease in lung function among school-age children in Period 3 when air quality improved substantially. The results suggest that the environmental protection policy in Jinan City has controlled PM2.5 pollution levels to some extent, which may have improved children's lung function.

Polycyclic Aromatic Hydrocarbons (PAHs) in Freshwater Systems: A Comprehensive Review of Sources, Distribution, and Ecotoxicological Impacts

This comprehensive review offers new perspectives on the distribution, sources, and ecotoxicological impacts of polycyclic aromatic hydrocarbons (PAHs) in freshwater systems. Unlike previous reviews, this work integrates recent findings on PAH dynamics within environmental matrices and emphasizes spatiotemporal variability across geographic regions. It critically examines both anthropogenic and natural sources, as well as the physical, chemical, and biological mechanisms driving PAH transport and fate. Special attention is given to the ecotoxicological effects of PAHs on freshwater organisms, including bioaccumulation, endocrine disruption, and genotoxicity. Notably, this review identifies key knowledge gaps and proposes an interdisciplinary framework to assess ecological risk and guide effective monitoring and management strategies for the protection of freshwater ecosystems.

Identification of key anthropogenic and land use factors and ecological risk assessment of dissolved polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs) in an urbanized estuary in China

This study investigated dissolved PAHs and OCPs in Quanzhou Bay estuaries, assessed their ecological risk, and examined anthropogenic impacts on contaminant distribution. Results showed that dissolved ∑24PAH concentrations ranged from 117 to 709 ng/L (mean: 358 ng/L), with dominance of 2-ring PAHs (Naphthalene, 1-Methylnaphthalene, and 2-Methylnaphthalene). Dissolved DDT levels ranged from 0.06 to 0.49 ng/L (mean: 0.28 ng/L), while HCBz concentrations varied from 0.02 to 0.44 ng/L (mean: 0.20 ng/L). PAHs were higher in the north due to urbanization and transport, while OCPs showed higher levels in the south due to historical agricultural use. Rural areas, water bodies, and wetlands significantly influenced the behavior of PAHs according to Spearman correlation and lasso regression analyses. Quanzhou Bay was categorized as a low to medium risk area based on dispersion simulation and ecological risk assessment, highlighting implications for future sustainable development and policy planning. CAPSULE: The coupled relationship between human activities and the distribution of dissolved PAHs and OCPs in urbanized estuaries was explored using statistical methods and GIS technology, providing valuable insights into environmental processes and pollutant control policies.

Distribution, sources, partition behavior and risk assessment of polycyclic aromatic hydrocarbons (PAHs) in the waters and sediments of Lake Ulansuhai, China

This study represents the first comprehensive investigation of 16 polycyclic aromatic hydrocarbons (PAHs) in the waters and sediments of Lake Ulansuhai. It explores their occurrence, sources, transport behavior, and associated risks to human health and ecosystems. The results revealed that concentrations of ∑PAHs in dissolved phase and sediment with no significant seasonal differences. In contrast, ∑PAHs concentrations in suspended particulate matter were significantly higher during the ice-free period compared to the ice period. Spatially, the northern part of Lake Ulansuhai displayed higher PAHs content. Diagnostic isomeric ratios and PMF models indicated that the PAHs were primarily derived from combustion sources. The distribution of PAHs within water-sediment demonstrated that non-equilibrium status. Fugacity calculations indicated that 2-4 rings PAHs acted as secondary sources of sediment emissions. Toxicity assessment, indicated that PAHs posed no significant carcinogenic risk to humans. Risk quotient values showed that PAHs as low to high ecological risk.