| Autor: |
Sowers TD; Center for Environmental Measurement and Modeling, Office of Research and Development, US Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States., Blackmon MD; Center for Environmental Measurement and Modeling, Office of Research and Development, US Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States., Wilkin RT; Center for Environmental Solutions and Emergency Response, Office of Research and Development, U.S. Environmental Protection Agency, Ada, Oklahoma 74820, United States., Rovero M; Center for Environmental Solutions and Emergency Response, Office of Research and Development, U.S. Environmental Protection Agency, Ada, Oklahoma 74820, United States., Bone SE; Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States., Jerden ML; Jacobs Technology, Inc., 109 T.W. Alexander Drive, RTP, North Carolina 27711, United States., Nelson CM; BioGeoChem Scientific, Austin, Texas 78748, United States., Bradham KD; Center for Environmental Measurement and Modeling, Office of Research and Development, US Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States. |
| Abstrakt: |
Residential lead (Pb) exposure is of critical concern to families globally as Pb promotes severe neurological effects in children, especially those less than 5 years old, and no blood lead level is deemed safe by the US Center for Disease Control. House dust and soils are commonly thought to be important sources of Pb exposure. Probing the relationship between house dust and soil Pb is critical to understanding residential exposure, as Pb bioavailability is highly influenced by Pb sources and/or species. We investigated paired house dust and soil collected from homes built before 1978 to determine Pb speciation, source, and bioaccessibility with the primary goal of assessing chemical factors driving Pb exposure in residential media. House dust was predominately found to contain (hydro)cerussite (i.e., Pb (hydroxy)carbonate) phases commonly used in Pb-based paint that, in-turn, promoted elevated bioaccessibility (>60%). Pb X-ray absorption spectroscopy, μ-XRF mapping, and Pb isotope ratio analysis for house dust and soils support house dust Pb as chemically unique compared to exterior soils, although paint Pb is expected to be a major source for both. Soil pedogenesis and increased protection from environmental conditions (e.g., weathering) in households is expected to greatly impact Pb phase differences between house dust and soils, subsequently dictating differences in Pb exposure. |
