Stable isotope was used to trace changes in Pb sources in PM2.5.
Artificial lysosomal fluid and Gamble's solution for Pb inhalation bioaccessibility in PM2.5.
Both coal combustion and smelting contribute to Pb sources in PM2.5.
Pollution control decreased PM2.5 and total Pb concentrations in Nanjing.
Pollution control changed Pb inhalation bioaccessibility in PM2.5.