RESUMO
A hybrid model based on the positive matrix factorization (PMF) model and the health risk assessment model for assessing risks associated with sources of perfluoroalkyl substances (PFASs) in water was established and applied at Dianchi Lake to test its applicability. The new method contains 2 stages: 1) the sources of PFASs were apportioned by the PMF model and 2) the contribution of health risks from each source was calculated by the new hybrid model. Two factors were extracted by PMF, with factor 1 identified as aqueous fire-fighting foams source and factor 2 as fluoropolymer manufacturing and processing and perfluorooctanoic acid production source. The health risk of PFASs in the water assessed by the health risk assessment model was 9.54 × 10-7 a-1 on average, showing no obvious adverse effects to human health. The 2 sources' risks estimated by the new hybrid model ranged from 2.95 × 10-10 to 6.60 × 10-6 a-1 and from 1.64 × 10-7 to 1.62 × 10-6 a-1 , respectively. The new hybrid model can provide useful information on the health risks of PFAS sources, which is helpful for pollution control and environmental management. Environ Toxicol Chem 2018;37:107-115. © 2017 SETAC.
Assuntos
Fluorocarbonos/análise , Modelos Teóricos , Medição de Risco , Monitoramento Ambiental , Geografia , Humanos , Lagos/química , Regressão Psicológica , Reprodutibilidade dos Testes , Água/química , Poluentes Químicos da Água/análiseRESUMO
PM10 and PM2.5 samples were simultaneously collected during a period which covered the Chinese New Year's (CNY) Festival. The concentrations of particulate matter (PM) and 16 polycyclic aromatic hydrocarbons (PAHs) were measured. The possible source contributions and toxicity risks were estimated for Festival and non-Festival periods. According to the diagnostic ratios and Multilinear Engine 2 (ME2), three sources were identified and their contributions were calculated: vehicle emission (48.97% for PM10, 53.56% for PM2.5), biomass & coal combustion (36.83% for PM10, 28.76% for PM2.5), and cook emission (22.29% for PM10, 27.23% for PM2.5). An interesting result was found: although the PAHs are not directly from the fireworks display, they were still indirectly influenced by biomass combustion which is affiliated with the fireworks display. Additionally, toxicity risks of different sources were estimated by Multilinear Engine 2-BaP equivalent (ME2-BaPE): vehicle emission (54.01% for PM10, 55.42% for PM2.5), cook emission (25.59% for PM10, 29.05% for PM2.5), and biomass & coal combustion source (20.90% for PM10, 14.28% for PM2.5). It is worth to be noticed that the toxicity contribution of cook emission was considerable in Festival period. The findings can provide useful information to protect the urban human health, as well as develop the effective air control strategies in special short-term anthropogenic activity event.
Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Férias e Feriados , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Atmosféricos/toxicidade , Poluição do Ar/estatística & dados numéricos , Atmosfera/química , Substâncias Explosivas/análise , Substâncias Explosivas/toxicidade , Humanos , Material Particulado/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Estações do Ano , Emissões de Veículos/análise , Emissões de Veículos/toxicidadeRESUMO
The concentrations of polychlorinated biphenyls (PCBs) in sediments from the Fenhe reservoir and watershed were detected at 28 sites in wet and dry seasons. The ∑(123)PCBs ranged from n.d. to 126.49 ng g(-1) dw. The dominated congeners were tri-PCBs (34.29%) and tetra-PCBs (24.05%). In the Fenhe reservoir, ∑(123)PCBs presented a decreasing trend, while percentages of low chlorinated congeners showed an increasing trend. For the temporal variations, PCBs homologues profiles of sediment samples and spatial distribution of ∑(123)PCBs for the two periods were similar (with CD = 0.021 and r(2) = 0.999 respectively), although PCBs concentrations in the wet season were significantly higher than in the dry season. PCA was applied to analyze the possible sources for PCBs, suggesting that PCBs might be mainly influenced by Aroclor 1016 and 1242. Compared with 3 established sediment quality guidelines, levels of PCBs in sediments of the investigated watershed might have a potential biological impact, especially in the wet season.
Assuntos
Monitoramento Ambiental , Água Doce/química , Sedimentos Geológicos/química , Bifenilos Policlorados/análise , Poluentes Químicos da Água/análise , China , Medição de Risco , Estações do Ano , Poluição Química da Água/estatística & dados numéricos , Abastecimento de Água/estatística & dados numéricosRESUMO
In this work, three receptor models (Principal Component Analysis-Multiple Linear Regression (PCA-MLR) model, Unmix model and Positive Matrix Factorization (PMF) model) were employed to investigate potential source apportionment of PAHs in sediments from Taihu Lake, China. A total of 15 priority PAHs in 29 sediments from Taihu Lake were measured, with ∑PAHs (sum of 15 PAHs) concentrations ranging from 209 to 1003 ng g(-1) dw. Source apportionment results derived from three different models were similar, indicating that the highest contribution to ∑PAHs was from vehicular emission (53.6-54.3%), followed by coal combustion (23.8-28.8%) and wood combustion (11.9-16.0%). The contribution of mixed wood and coal combustion source identified by PCA-MLR was 41.3%. For the first time the risk assessment for each identified source category was quantitatively calculated by combining the BaP equivalents (BaPE) values with estimated source contributions. The results showed that vehicular emission posed the highest toxic risk, with BaPE values of 26.9-31.5 ng g(-1) dw, and the BaPE values for coal combustion and wood combustion were 6.56-15.6 ng g(-1) dw and 2.94-6.11 ng g(-1) dw, respectively. The distributions of contribution and BaPE for each identified source category were studied as well, and showed similar trends among the sampling sites, for each source category.