The World Health Organization (WHO) has updated its fact sheet on lead poisoning and health.
Background information:
Lead is a naturally occurring toxic metal found in the Earth’s crust.
Its widespread use has resulted in extensive environmental contamination, human exposure and significant public health problems in many parts of the world.
More than three quarters of global lead consumption is for the manufacture of lead-acid batteries for motor vehicles.
Lead is, however, also used in many other products, for example
pigments,
paints,
solder,
stained glass,
crystal vessels,
ammunition,
ceramic glazes,
jewellery,
toys,
some cosmetics, and
traditional medicines.
Drinking water delivered through lead pipes or pipes joined with lead solder may contain lead. Much of the lead in global commerce is now obtained from recycling.
Young children are particularly vulnerable because they absorb 4–5 times as much ingested lead as adults from a given source. They can suffer profound and permanent adverse health effects, particularly affecting the development of the brain and nervous system.
Lead also causes long-term harm in adults, including increased risk of high blood pressure and kidney damage.
Exposure of pregnant women to high levels of lead can cause miscarriage, stillbirth, premature birth and low birth weight, as well as minor malformations.
People can become exposed to lead through occupational and environmental sources. This mainly results from:
inhalation of lead particles generated by burning materials containing lead, e.g. during smelting, informal recycling, stripping leaded paint and using leaded gasoline; and
ingestion of lead-contaminated dust, water (from leaded pipes), food (from lead-glazed or lead-soldered containers).
Exposure to lead-contaminated soil and dust resulting from battery recycling and mining has caused mass lead poisoning and multiple deaths in young children in Senegal and Nigeria.
Once lead enters the body, it is distributed to organs such as the brain, kidneys, liver and bones.
The body stores lead in the teeth and bones where it accumulates over time.
Lead stored in bone may be re-mobilized into the blood during pregnancy, thus exposing the fetus.
Undernourished children are more susceptible to lead because their bodies absorb more lead if other nutrients, such as calcium, are lacking.
Children at highest risk are the very young (including the developing fetus) and the impoverished.
Key Messages:
Lead is a cumulative toxicant that affects multiple body systems and is particularly harmful to young children.
Childhood lead exposure is estimated to contribute to about 600 000 new cases of children developing intellectual disabilities every year.
Lead exposure is estimated to account for 143 000 deaths per year with the highest burden in developing regions.
Lead exposure is estimated to account for 4% of the global burden of ischaemic heart disease and 5% of the global burden of stroke.
About one half of the burden of disease from lead occurs in the WHO South-East Asia Region, with about one-fifth each in the WHO Western Pacific and Eastern Mediterranean Regions.
Lead in the body is distributed to the brain, liver, kidney and bones. It is stored in the teeth and bones, where it accumulates over time.
Human exposure is usually assessed through the measurement of lead in blood.
There is no known level of lead exposure that is considered safe.
Lead poisoning is entirely preventable.
Useful Links:
Link to the updated fact sheet:
http://who.int/mediacentre/factsheets/fs379/en/
Link to WHO page listing 10 chemicals of major public health concern:
http://who.int/ipcs/assessment/public_health/chemicals_phc/en/
