Inorganic lead is certainly the most extensively studied of all toxic agents. Occupational exposure occurs in a wide variety of settings. There is also widespread exposure in the general environment. However, after the ban of lead addition to petrol, the exposure has decreased dramatically in several parts of the world. Exposure and risk are usually assessed by biological monitoring, mainly by blood-lead concentration (B-Pb). However, B-Pb has limitations, because there is saturation at high exposure. Lead accumulates in teeth and in the skeleton, where it may be determined by in vivo methods, which reflect long-term uptake. Toxic effects may occur in the central and peripheral nervous systems, blood (including inhibition of heme synthesis, which also affects other cells), kidney, and cardiovascular, endocrine and immune systems, gastrointestinal tract, and male reproduction (sperm quality). Lead causes increase of blood pressure; slight effects may occur in adults with a mean B-Pb of 0.4 mu mol/L. Furthermore, lead passes the placenta and may cause effects on the nervous system of the fetus. Lead in the skeleton is mobilized during pregnancy and lactation and is transferred to both the fetus and the lactating infant. Slight (but adverse) effects on the mental development of infants and children have repeatedly been reported at a mean B-Pb of 0.5 mu mol/L, or even less, in the pregnant woman or the child. Lead is carcinogenic in animal experiments, but there is only limited evidence for carcinogenicity in humans. The most important organolead compounds are tetraethyl and tetramethyl lead, which have been used in enormous quantities in leaded petrol. They are easily absorbed through inhalation and through the skin and may cause acute encephalopathia.
San Diego: Elsevier, 2007, 3. 599-643 p.