One in three children have dangerous levels of lead in their blood

About 800 million children and young people under the age of 19 around the world are likely to have blood levels of lead at or above 5 micrograms per decilitre (5μg/dl), the levels that are likely to cause significant long-term health damage.

There is no safe level for lead exposure, according to the World Health Organization, because even at very low concentrations it operates as a dangerous toxin, but levels above 5μg/dl are regarded by the US Centers for Disease Control as a cause for action.

Lead is a potent neurotoxin and high exposure can kill, while lower levels cause symptoms ranging from pain, vomiting and seizures to developmental delay, mental difficulties and mood disorders. The lower levels can also cause children to be born prematurely.

Exposure at the levels studied is likely to cause reductions in cognitive ability, higher levels of violence and long term health impacts such as cardiovascular disease.

Children are particularly vulnerable to lead exposure because it damages the developing brain and nervous system, building up over time, and the impacts do not show immediately. Lead mimics calcium in the bones, building up in people’s bodies and causing damage to other vital organs, including the kidneys, heart and lungs.

Lead at 5μg/dl of blood is likely to wipe about 3-5 points from a child’s IQ score, and at the levels found in the Unicef report could double the level of violence in society. It is also likely to increase the risk of cardiovascular disease, as about 900,000 deaths a year are already linked to lead poisoning.

One of the leading causes of lead poisoning is the improper disposal of car batteries, A further cause of lead poisoning is the use of lead compounds, such as lead oxide and lead chromate, as a food additive to make spices appear more vivid in colour. The compounds are used to make turmeric appear bright yellow, and sometimes used with paprika. 

Children in developed countries are also at risk, from sources including old water pipes, lead paint and contaminated soil. In the US, children living in poorer households and dilapidated accommodation have been found to be at higher risk. In the UK, about 200,000 children are likely to be affected, according to Unicef.