These data were collected by the EPA Toxic Element Bioavailability Laboratory and consists of lead (Pb) and/or arsenic (As) mouse tissue, soil, aqueous soil leachate, and spectroscopy data. The mouse-based assay for assessment of lead and arsenic in vivo mouse bioavailability in soil and dust is a critical tool needed to improve our understanding of the factors affecting the metal’s uptake across the gastrointestinal barrier and to evaluate the efficacy of methods used to remediate lead and/or arsenic contaminated media. The mouse assay has been optimized to yield accurate, reproducible, and reliable estimates of the in vivo mouse bioavailability of lead and/or arsenic in soil and dust. The reported Pb/As data is used to assess the total, bioaccessible, and bioavailable concentrations resulting from exposure to soils. These data were collected using EPA Methods 1340, 3050b, 6010d, and 6020b. These quantitative characterization data are then paired with X-ray absorption spectroscopy data that is used to deduce the valence, coordination environment, and mineral/sorbed phase of the element of interest. These data are collected at a synchrotron facility by our team and then processed at EPA ORD using previously established methods (e.g., Sowers et al., 2023).