Exposure to lead
Situation and trends
Because of its many uses, lead is present in air, dust, soil and water. Exposure to lead in the womb and during childhood reduces intelligence quotient (IQ), among other behavioural and developmental effects; for adults, it increases blood pressure which leads to an increased risk of cardiovascular diseases. In 2004, 49% of the world's children under the age of five years and 42% of adults were estimated to have blood lead levels above 5 micrograms/dl, leading to adverse health effects. 16% of children under age five and 13% of adults even experienced blood lead levels above 10 micrograms/dl.
Overall, 98% of adults and 99% of children affected by the higher exposures (10 micrograms/dl) to lead live in low- and middle-income countries. Certain population groups in industrialized countries are also still exposed to high lead levels, often from degraded housing. Blood lead levels have been steadily declining in many countries following the wide-spread phasing-out of leaded fuels. Between the years 2000 and 2004 the global proportion of children with blood lead levels above 10 micrograms/dl has declined from 20% to 16%. Leaded petrol has been a major contributor to elevated blood lead levels, however other sources of lead, such as lead-glazed ceramics, food cans, drinking water, dust, leaded paints, toys, or batteries can also be of relevance.