NCIt definition : An inorganic or organic substance that contains the metallic element lead either in
its positive-2 or 4 valence state. Lead compounds have a wide variety of applications
in industry. Exposure to lead compounds affects the lungs, central nervous system
and kidneys. Lead compounds are possible mutagens and are reasonably anticipated to
be human carcinogens. The substance may be associated with an increased risk of developing
lung and stomach cancer. (NCI05);