title: In vitro bioaccessibility of lead in surface dust and implications for human exposure: A comparative study between industrial area and urban district.
abstract: In this study, ground surface dust samples from two contrasting areas, a former zinc smelting area in Guizhou Province and a common urban district in Wuhan city, Hubei Province, China, were assessed for in vitro Pb bioaccessibility using a physiologically based extraction test (PBET). Extremely elevated concentrations of Pb (220-6348 mg/kg) and other trace metals were observed in the zinc smelting area. While moderate high metal concentrations (79-1544 mg/kg of Pb) in the urban dusts were attributed to various urban activities, coal combustion and traffic emissions. Lead bioaccessibility in the stomach-phase varied from 17.6 to 76.1% and no significant difference was found between industrial and urban dust samples. Compared with the stomach-phase, Pb bioaccessibility in the more alkaline intestinal-phase was considerably lower (1.2-21.8%). A significantly negative correlation was found between dust Ca concentrations and Pb bioaccessibility in the intestinal-phase, suggesting that Ca plays an important role in reducing the bioaccessible Pb in the intestinal-phase. The estimated Pb exposure based on gastric bioaccessible Pb was 13.9 and 1.8 μg/kg day for children living in the industrial and urban areas, respectively, accounting for 85% and 41% of their corresponding total Pb exposure.
authors.affiliation: State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan 430074, China; School of Earth Sciences, China University of Geosciences, Wuhan 430074, China. Electronic address: bixy@cug.edu.cn.
authors.forename: Xiangyang
authors.initials: X
authors.lastname: Bi
authors.affiliation: State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China.
authors.forename: Zhonggen
authors.initials: Z
authors.lastname: Li
authors.affiliation: State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China.
authors.forename: Guangyi
authors.initials: G
authors.lastname: Sun
authors.affiliation: School of Earth Sciences, China University of Geosciences, Wuhan 430074, China.
authors.forename: Jinling
authors.initials: J
authors.lastname: Liu
authors.affiliation: Institute of Geophysical and Geochemical Exploration CAGS, Langfang 065000, China.
authors.forename: Zhixuan
authors.initials: Z
authors.lastname: Han
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D000397:Air Pollution; D001682:Biological Availability; D002118:Calcium / Q000737:chemistry; D002648:Child; D002681:China; D002947:Cities; D004391:Dust / Q000032:analysis*; D004781:Environmental Exposure / Q000032:analysis; D006801:Humans; D007221:Industry; D007422:Intestines / Q000187:drug effects; D007854:Lead / Q000032:analysis*; D016016:Proportional Hazards Models; D018570:Risk Assessment; D012989:Soil Pollutants / Q000032:analysis*; D013270:Stomach / Q000187:drug effects; D014131:Trace Elements; D014961:X-Ray Diffraction; D015032:Zinc / Q000737:chemistry
chemical_list: D000393:Air Pollutants; D004391:Dust; D012989:Soil Pollutants; D014131:Trace Elements; D007854:Lead; D015032:Zinc; D002118:Calcium
keywords: Bioaccessibility; Dust; In vitro PBET; Lead