Lead [Pb, 82]

Lead, a metal of the group 14 in the periodic table of elements, occurs in the Earth’s crust at the mean content of 15 mg/kg. Lead contents of coal vary within the broad range from 10 to 1900 mg/kg, and may be concentrated in fly ash up to about 50 mg/kg. Lead environmental pollution is presently of a great concern. Lead concentrations in the ice cores decreased after the decline of the Roman Empire, and did not surpass Roman levels, until the start of the Industrial Revolution. Lead pools in mountain forest soils of the National Park in Poland range between 0.16 and 15.6 mg/kg, and is concentrated in forest litter, often over 100 mg/kg. Lead behavior in water depends on the pH and dissolved salts of other elements and organic matter. Lead particles/aerosols in the atmosphere are finely deposited in terrestrial and aquatic systems.