The World Health Organization (WHO) on Thursday informed countries to bolster efforts to prevent lead exposure, which has affected hundreds of millions of children worldwide.
“Lead poisoning is one of the world's most serious yet overlooked environmental health threats," said Bruce Gordon, head of the WHO's environment department.
The WHO categorised lead, a naturally occurring toxic metal found in the Earth's crust, as one of the 10 chemicals of major public health concern, which also include arsenic, asbestos, mercury and highly toxic pesticides.
Lead exposure is estimated to contribute more than 3.5 million preventable deaths globally every year.
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According to the WHO, 815 million children have blood levels of at least five microgrammes per decilitre, which its guidelines say should initiate investigations into the cause of lead exposure and actions to reduce or end it.
"Over one in three children around the world are above WHO's action level," Gordon told reporters.
"A child can be exposed without showing any obvious symptoms," he added.
Children are particularly prone to the dangers of lead, as their brains are still developing and their nervous systems vulnerable to its toxic effects.
The widespread use of lead has resulted in extensive environmental contamination, human exposure and significant health problems, says the WHO.
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"Exposure can occur through paint, cookware, cosmetics, spices, informal recycling and industrial contamination, among other sources," it says.
"There is no known safe level of lead exposure, and even relatively low exposure can cause irreversible harm."
Upon exposure, lead spreads to organs such as the kidneys, brain, and liver, as well as to the bones.
Awareness is 'not enough'
In 2021, the WHO recommended identifying and eliminating the source of contamination for any individual with a blood lead level of at least five microgrammes per decilitre.
The health body pointed out that 3.5 microgrammes can be associated with reduced intelligence, behavioural disorders and learning difficulties in children.
Countries have recognised Lead exposure as a major public health concern and tasked the WHO with developing a global action plan to be presented at their next annual assembly in May.
The WHO said it was improving laboratory capacity to conduct blood lead level testing in Brazil, India, Nepal, Ethiopia, Ghana, Malawi, Rwanda, South Africa and Tanzania.
"Awareness alone is not enough, and we need to move to effective policymaking and enforcement," said Gordon.
WHO’s latest assessment also highlighted that fewer than half of the countries had legally binding controls on lead in paint.
"Countries now need to move upstream, removing lead from products and environments before it reaches a child's bloodstream," Gordon said.
(With inputs from AFP)