The EPA regulations for lead concentrations in soil are 400 ppm(parts per million) for residential property, child-occupied facilities, or play areas. In other regions, 1200 ppm is the regulation (U.S. Environmental Protection Agency, Region III. 2020). EPAs action level of water is 15 ppb (parts per billion). EPA lead air regulation is 0.15 µg/m^3. For people in industries, the workplace air regulation for OSHA (Occupational Safety and Health Administration) is 50 µg/m^3 (Agency for Toxic Substances and Disease Registry. Environmental. 2017).
U.S. Environmental Protection Agency, Region III. 2020. Lead in soil.
https://www.epa.gov/sites/default/files/2020-10/documents/lead-in-soil-aug2020.pdf
Agency for Toxic Substances and Disease Registry. Environmental. 2017. Health and Medicine Education. https://www.atsdr.cdc.gov/csem/leadtoxicity/safety_standards.html#:~:text=EPA%20has%20established%20400%20ppm,systems%20is%2015%20%C2%B5g%2FL