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1.
Huan Jing Ke Xue ; 40(7): 3008-3017, 2019 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854698

RESUMO

To evaluate the pollution level, congener distribution, and human exposure of polybrominated diphenyl ethers (PBDEs) in the atmosphere of Beijing's office buildings, outdoor air samples (particles+gas) were collected from a typical scientific area and PBDEs concentrations were quantified using GC-MS. The results showed that the mass concentrations of PBDEs in the gas phase, PM2.5, and PM10 were 2.3-78.6 pg·m-3, 14.4-335.3 pg·m-3, and 11.6-431.7 pg·m-3, respectively, and the annual average mass concentrations were 21.7 pg·m-3, 96.9 pg·m-3, and 149.3 pg·m-3, respectively. BDE-209 was the predominant congener in particulates, accounting for 50% of the total concentration. The mass concentration of PBDEs in the particles decreased in the following order:autumn > winter > summer > spring, with an obvious change in winter and stability in summer. Tri-BDEs mainly existed in the gas phase, and the proportion of PBDEs in the particle phase increased with bromine number. Source analysis indicated that BDE-209 degradation was an important source of other PBDEs in the air. Exposure risk analysis showed that the respiratory intake of children and adults was 18.6 pg·(kg·d)-1 and 7.1 pg·(kg·d)-1, respectively, which is far below the recommended lowest observed adverse effect level of 1 mg·(kg·d)-1. Similarly, the carcinogenic risk values of BDE-209 for children and adults were 2.3×10-9 and 3.7×10-9, respectively, which were much smaller than the carcinogenic risk limit of 10-6, indicating that there was no health hazard from PBDEs in the atmosphere.

2.
Arch Environ Contam Toxicol ; 76(2): 255-264, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30390119

RESUMO

Surface waters from five districts in the inner city of Beijing were collected for analysis of 43 target compounds of pharmaceuticals and personal care products (PPCPs) to understand the spatial distribution patterns of different groups of PPCPs in the central urban area of a metropolitan city characterized by many hospitals and public parks. The total concentrations of PPCPs showed large spatial variability, ranging from 71.1 to 2400 ng/L. The x-ray contrast medium iopromide was the compound with the highest concentrations. Pharmaceuticals showed similar spatial distributional patterns with large hospitals. Positive correlations between iopromide and pharmaceuticals were observed. In contrast, in general there is no correlation between iopromide and personal care products. The concentrations of PPCPs in the landscape waters were not high but were characterized by high proportions of acidic, nonsteroidal anti-inflammatory drugs with low or even negative removal efficiencies in the WWTP in Beijing, suggesting that the reclaimed water irrigation can be another source of PPCPs in surface waters in the inner city of Beijing.


Assuntos
Irrigação Agrícola , Cosméticos/análise , Preparações Farmacêuticas/análise , Poluentes Químicos da Água/análise , China , Monitoramento Ambiental , Hospitais
3.
Arch Environ Contam Toxicol ; 74(3): 484-491, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28965150

RESUMO

High levels of perfluoroalkyl substances (PFASs) were observed in rural areas near a fluorochemical industrial park (FCIP) in the Yangtze River Delta region. The concentrations of total PFAS (∑PFASs) in soil, surface water, groundwater, and rainwater were in the range of 0.6-64.6 ng/g dry weight, 15.6-480.9, 4.8-614.6, and 13.4-542.2 ng/L, respectively. PFASs in rainwater and groundwater were higher than in surface water. The influence of the FCIP on rural soils extended to a distance of approximately 4 km based on the changes in PFAS compositions. The impact on surface water is mainly through direct river flow connected with contaminated sources, which may extend farther than 7 km in the case of unrestricted flow but much shorter distance for unconnected rivers. The penetration of PFASs in groundwater aquifers can extend as far as ca. 6 km, while direct water flow is the main transport route for PFASs. The influence radius of the FCIP can be as far as 60 km due to atmospheric precipitation.


Assuntos
Indústria Química , Fluorocarbonos/análise , Poluentes do Solo/análise , Poluentes Químicos da Água/análise , China , Meio Ambiente , Monitoramento Ambiental , Água Subterrânea/química
4.
Chemosphere ; 185: 610-617, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28719881

RESUMO

Perfluoroalkyl acids (PFAAs) are widely used as multi-purpose surfactants or water/oil repellents. In order to understand the contamination level and compositional profiles of PFAAs in aqueous environment in textile, leather, and paper making industrial areas, surface waters and tap waters were collected along the watershed of the Qiantang River where China's largest textile, leather, and paper making industrial bases are located. For comparison, surface water and tapwater samples were also collected in Hangzhou and its adjacent areas. 17 PFAAs were analyzed by solid phase extraction-high performance liquid chromatography-tandem mass spectrometry. The results show that the total concentrations of PFAAs (ΣPFAAs) in the Qiantang River waters ranged from 106.1 to 322.9 ng/L, averaging 164.2 ng/L. The contamination levels have been found to be extremely high, comparable to the levels of the most serious PFAA contamination in surface waters of China. The PFAA composition profiles were characterized by the dominant PFOA (average 58.1% of the total PFAAs), and PFHxA (average 18.8%). The ΣPFAAs in tap water ranged from 9.5 to 174.8 ng/L, showing PFAA compositional pattern similar to the surface waters. Good correlations between PFAA composition profiles in tap waters and the surface waters were observed.


Assuntos
Água Potável/química , Monitoramento Ambiental , Fluorocarbonos/análise , Curtume/estatística & dados numéricos , Indústria Têxtil/estatística & dados numéricos , Águas Residuárias/análise , Poluentes Químicos da Água/análise , Ácidos Alcanossulfônicos/análise , China , Água Doce/química , Indústrias , Papel , Rios/química , Extração em Fase Sólida , Tensoativos/análise , Têxteis/análise , Águas Residuárias/estatística & dados numéricos , Água/análise
5.
Bull Environ Contam Toxicol ; 99(2): 224-231, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28528484

RESUMO

The contamination status of perfluoroalkyl substances (PFASs) were investigated in 64 tapwater samples collected from 17 cities and 45 surface water samples from adjacent areas in the eastern China. The total PFAS concentrations in tapwater ranged from 1.4 to 175 ng/L; relatively higher PFAS levels were observed in samples collected from the Yangtze River Delta region, which was similar to the geographical distribution pattern of PFAS levels observed in rivers and lakes. The highest total PFASs in tapwater was found in Changshu, where several fluorine-related industries are located, whereas the lowest was observed in Beijing. Significant positive correlations between PFAS compositions in tap water sample and their source waters were noted. Several industries such as paper, textile, and leather industries may contribute to the contamination of PFASs in tapwater.


Assuntos
Água Potável/química , Monitoramento Ambiental , Fluorocarbonos/análise , Poluentes Químicos da Água/análise , Pequim , Caprilatos , China , Cidades , Fluoretos/análise , Flúor/análise , Lagos , Rios , Água
6.
Environ Pollut ; 211: 124-31, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26745397

RESUMO

Little research on perfluorinated compounds (PFCs) has been conducted in rural areas, although rural PFC sources are less complicated than in urban and industrial areas. To determine the levels and geographical distribution of 17 PFC compounds, samples of soil, surface water, and groundwater were collected from eight rural areas in eastern China. The total PFC concentrations (∑PFCs) in soils ranged from 0.34 to 65.8 ng/g ∑PFCs in surface waters ranged from 7.0 to 489 ng/L and ∑PFCs in groundwater ranged from 5.3 to 615 ng/L. Ratios of perfluorononanoic acid/perfluorooctanoic acid (PFNA/PFOA), perfluoro-n-butyric acid/perfluorooctanoic acid (PFBA/PFOA), and perfluoroheptanoic acid/perfluorooctanoic acid (PFHpA/PFOA) in rainwater increased due to the fluorine chemical plants in the surrounding rural and urban areas, suggesting that atmospheric precipitation may carry PFCs and their precursors from the fluorochemical industrial area to the adjacent rural areas.


Assuntos
Fluorocarbonos/análise , Água Doce/química , Água Subterrânea/química , Solo/química , Poluentes Químicos da Água/análise , Caprilatos/análise , China , Monitoramento Ambiental , Indústrias
7.
Huan Jing Ke Xue ; 31(7): 1625-30, 2010 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-20825036

RESUMO

The concentrations of polycyclic aromatic hydrocarbons (PAHs) in the paddy root-soil system were determined to study the dynamic and the influencing factors during crop rotation period. It showed that the dynamic of PAHs in paddy roots was most correlative with the factor of root surface area, but less correlated with PAHs in air and particles, which indicates that the physiological characters rather than the environment media are the main factors influencing the PAHs accumulation in paddy roots. According to the EPA risk standard about BaP and sigma PAHs, the PAHs accumulation in the paddy seeds won't decrease the food security to human being. The PAHs concentrations in paddy soil showed a declined trend during the period of paddy growth, which was affected not only by the processes of water elution and microbe degradation, but also depended on the absorption rate of paddy roots. When the crop rotation begins and paddy planting rolls into the next growing period, the PAHs in the paddy soil will again increase into a higher level which is correlated with the TOC content in the soil.


Assuntos
Agricultura/métodos , Oryza/crescimento & desenvolvimento , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/análise , Solo/análise , Biodegradação Ambiental
8.
Huan Jing Ke Xue ; 27(4): 760-4, 2006 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-16768002

RESUMO

Intact rice roots, ambient air, soil and irrigation water samples were collected from two sites at Baodi and Xinli, Tianjin. The rice roots were separated into nodal roots and lateral roots, which were extracted individually using a three-step sequential extraction procedure to measure the sorbed, strongly sorbed and interior adsorbed fractions. The results show that remarkable difference of PAH contents between the samples from the two sites and relatively higher PAH contents in the lateral roots than those in the nodal roots, around 60% of the total PAHs detected were those absorbed in the root tissues. Specific surface area and lipid content of the roots are main factors influencing PAH contents.


Assuntos
Oryza/metabolismo , Raízes de Plantas/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Poluentes do Solo/metabolismo , Absorção
9.
Huan Jing Ke Xue ; 25(4): 23-7, 2004 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-15515930

RESUMO

Leaves of 6 plants were collected from two sites on and around Peking University campus in summer season of 2003. PAHs in the leaf-wax and tissues were determined simultaneously with leaf-wax content, tissue lipid, specific surface, and stomata density. The results were compared to investigate the possible sources of PAHs in the leaves. For both leaf-wax and tissue samples, levels of PAHs depended on plant species and were lower in the samples from campus than those from outside of campus in short distance to busy traffic, suggesting a significant influence of vehicle emission. The concentrations of PAHs in leaf-wax were 1-2 orders of magnitude higher than those in leaf tissues. While the PAH profiles in the leaf-wax and leaf tissues were similar in general, the relative contents of volatile compounds were higher in the tissues than in the wax. Negative correlations were identified between PAHs concentration in the leaf-wax and the wax content and between the tissue PAH content and stomata density.


Assuntos
Poluentes Atmosféricos/análise , Folhas de Planta/química , Hidrocarbonetos Policíclicos Aromáticos/análise , China , Estações do Ano
10.
Huan Jing Ke Xue ; 25(2): 162-5, 2004 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-15202256

RESUMO

A five-step sequential elution procedure with or without supersonic effect was tested for extraction of foliar dust from leaves of Euonymus japonicus collected at two locations of Beijing urban area. The samples were collected from either roadside or campus far away from any motor traffic. The foliar dust was characterized for size distribution, organic carbon content, and PAHs content. It was found that majority of the foliar dust can be eluted in 4 min by distill water under supersonic effect at room temperature without shaking. The amount of foliar dust on the sample from roadside was almost twice as much as those from campus, while the particle size of the former was relatively large. Large amount of coarse particles came from disturbance of motor vehicles. Slightly high concentrations of PAH species were detected in the sample from campus compared to those in the samples collected from roadside.


Assuntos
Poeira/análise , Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Cidades
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