Lead harms children's brains at levels once thought safe, and a 2020 UNICEF and Pure Earth analysis estimated that around one in three children worldwide, up to 800 million, have blood lead levels at or above 5 µg/dL, the level at which WHO recommends finding and stopping the source.
Written from the sources listed below, not independently peer-reviewed.
Roughly how many children worldwide are estimated to have blood lead levels high enough (5 µg/dL or more) to call for action?
Up to 800 million
Children with blood lead at or above 5 µg/dL
Around one in three children worldwide, according to a modelled estimate published by UNICEF and Pure Earth in July 2020.
Data year 2020. Source: UNICEF and Pure Earth, 2020
Over 3.5 million
Deaths attributed to lead exposure
All ages, mainly from cardiovascular effects, as modelled by the Global Burden of Disease Study 2023 (IHME) and cited by WHO. The same estimate puts the loss of healthy life at more than 71.5 million DALYs.
Data year 2023. Source: World Health Organization, 2026
48%
Countries with legally binding controls on lead paint
Status as of 16 January 2024, up from 43% at the end of 2021. The other half of countries had no binding control or no data.
Data year 2024. Source: World Health Organization, 2024
Status as of 31 December 2021 and 16 January 2024, as reported by WHO's Global Health Observatory; these are the only two points the page reports. A country counts if it has any legally binding control on lead paint, whatever its limit or enforcement. No comparable global time series exists for children's blood lead levels.
SDG target 3.9 calls for a substantial reduction in deaths and illness from hazardous chemicals and pollution by 2030. The removal of lead from petrol was completed in 2021, but as of January 2024 only 48% of countries had binding controls on lead paint, and no global target or regular measurement exists for children's blood lead, so progress against the burden itself cannot be tracked.
A systematic review of blood lead studies from 49 low- and middle-income countries estimated that 632 million children in these countries, or 48.5%, had blood lead above 5 µg/dL, based on pooled data from 34 countries.
Source: Ericson B, Hu H, Nash E, Ferraro G, Sinitsky J, Taylor MP, 2021About half of children in low-income countries are estimated to have elevated blood lead, compared with about 3% in high-income countries; across 34 low- and middle-income countries the average child level is about 5.3 µg/dL, roughly ten times the average in the United States.
Source: Crawfurd L, Todd R, Hares S, Sandefur J, Silverman Bonnifield R, 2025Average child blood lead differed widely between low- and middle-income countries, from 1.66 µg/dL in Ethiopia to 9.30 µg/dL in Palestine, in studies published between 2010 and 2019.
Source: Ericson B, Hu H, Nash E, Ferraro G, Sinitsky J, Taylor MP, 2021Young children and unborn babies are the most vulnerable: children absorb four to five times as much lead as adults from the same swallowed dose, hand-to-mouth behaviour adds exposure, and lead stored in a mother's bones is released during pregnancy.
Source: World Health Organization, 2026Instead of one “percent solved” score, DO GOOD rates three separate dimensions. A problem can have mature solutions that still reach too few people. These ratings are an editorial reading of the sources on this page, not a measured index.
Has the situation improved in the real world?
ModerateEnding leaded petrol removed the largest historical source and, according to UNEP, prevents more than 1.2 million premature deaths a year. Yet modelled estimates still place up to 800 million children at or above 5 µg/dL.
How mature and validated are the available solutions?
ModerateProduct bans are proven and cheap: the petrol phase-out worked worldwide, and regulatory action against lead chromate in spices in Bangladesh and Georgia was effective at low cost. Cleaning up contaminated sites and informal battery recycling is much harder and more expensive.
How widely are effective solutions actually used?
ModerateLead-free petrol is universal, but binding paint controls cover only 48% of countries, and most low- and middle-income countries lack them; action on spices, cookware and battery recycling exists in only a few places.
The 2021 systematic review found usable blood lead studies in only 49 of 137 low- and middle-income countries, and its estimate for children pooled background data from 34 countries, so global numbers rest heavily on modelling.
The share of countries with paint controls rose from 43% to 48% between 2021 and 2024 and leaded petrol is gone, but there is no evidence of a measurable fall in children's blood lead in the countries most affected, where consumer products and recycling remain largely unregulated.
Lead is a metal that the body cannot use and that WHO says has no known safe level of exposure. It travels to the brain, liver, kidneys and bones and builds up in bones and teeth over time. Young children are most at risk: from the same swallowed dose they can absorb four to five times as much lead as adults, and children short of calcium or iron absorb more. Even at low levels lead can permanently affect brain development, lowering IQ, changing behaviour and reducing how far children get in school; WHO notes that blood levels as low as 3.5 µg/dL may be linked to lower intelligence. During pregnancy, lead stored in the mother's bones returns to the blood and reaches the fetus.
Leaded petrol, once the main source, was finally ended worldwide in 2021. Today children are exposed through fumes and dust from smelting and battery recycling, old and new lead paint, contaminated soil, water and food, spices adulterated with lead chromate, cookware and ceramic glazes, toys, cosmetics and some traditional medicines. The burden falls overwhelmingly on low- and middle-income countries, where a 2021 systematic review estimated that about 632 million children had blood lead above 5 µg/dL. Across all ages, the Global Burden of Disease study attributed more than 3.5 million deaths in 2023 to lead exposure, mostly through heart and blood vessel disease.
Lead exposure is measured by the concentration of lead in a person's blood, in micrograms per decilitre (µg/dL). Global figures are mostly modelled from a limited number of blood surveys, while policy progress is tracked by whether countries have laws limiting lead in products such as paint.
Blood lead concentration
WHO assesses human exposure by measuring lead in blood. Lead also accumulates in bones and teeth over time and can be released back into the blood later, for example during pregnancy.
The 5 µg/dL action level
WHO's 2021 guidelines on clinical management recommend that when a person's blood lead is 5 µg/dL or higher, the source of exposure is identified and action taken to stop it. Global estimates of 'elevated' blood lead in children use this same cut-off.
No safe threshold
The 5 µg/dL level is a trigger for action, not a safe limit: WHO states that no blood lead concentration is known to be without harm, and lower levels may already be associated with reduced intelligence in children.
Legally binding controls on lead paint
WHO tracks whether each country has a law, regulation or binding standard that controls the production, import, export, sale or use of lead paint, based on WHO and UNEP surveys of national authorities. Each country is recorded simply as yes, no or no data, so the indicator says nothing about how strict the limit is or how well it is enforced.
What works
UNEP's campaign began in 2002, when 117 countries still used leaded petrol; Algeria was the last to stop, in July 2021. UNEP estimates the phase-out prevents more than 1.2 million premature deaths a year.
Limits
It is complete, so it offers no further gains, and it does nothing about the sources that now dominate, such as batteries, paint, spices and cookware.
What works
Laws that control the making, import and sale of lead paint stop new exposure at the source; WHO and UNEP promote them through the Global Alliance to Eliminate Lead Paint, and 48% of countries had them by January 2024.
Limits
Over half of countries still lack binding controls, laws need testing and enforcement to work, and they do not remove lead paint already on walls, which releases lead when it is stripped or sanded.
What works
Lead chromate is added to some turmeric and other spices to brighten the colour. Regulatory action against this practice in Bangladesh and Georgia has been reported as effective and inexpensive.
Limits
It depends on market testing, enforcement and cooperation from traders, and documented successes so far come from a small number of countries.
What works
WHO's 2021 guidelines recommend that anyone with blood lead of 5 µg/dL or more has the source identified and stopped, which can find contaminated products, homes or workplaces affecting whole communities.
Limits
Testing needs laboratories or reliable devices and trained staff that many countries lack, and a test only helps if the source can actually be removed.
What works
Most lead is used to make lead-acid batteries for vehicles, and informal recycling is a main source of exposure in low- and middle-income countries, so regulating the battery industry and cleaning up polluted soil around smelters protects nearby children.
Limits
Remediation of contaminated sites has proven expensive, and informal recycling often operates outside any licensing system.
Promising, but not proven at scale. The stage shows how far each approach has come; it is not a recommendation.
Portable analysers allow teams to test paints, cookware, ceramics, toys and spices for lead on the spot, showing regulators which products to target. Results depend on follow-up enforcement and on laboratory confirmation for borderline samples.
Measuring blood lead in nationally representative household surveys would replace modelled guesses with direct data for children. Only a few countries have done this so far, and it requires careful sample handling and laboratory quality control.
Combining enforcement, public information and work with traders and mills, as done for turmeric in Bangladesh, is being considered for other countries and spices. Whether the approach transfers to supply chains with different structures is not yet known.
Efforts to move battery recycling from backyard operations into licensed plants with emission controls aim to cut exposure in surrounding neighbourhoods, but the economics of informal recycling make the shift slow.
Implementation gap
As of January 2024, 52% of countries had no legally binding control on lead paint or no data, and most low- and middle-income countries do not regulate the sale of lead paint.
Implementation gap
Most of the world's lead goes into lead-acid batteries, and informal recycling and manufacturing are among the main sources of high blood lead in low- and middle-income countries.
Knowledge gap
Between 2010 and 2019, usable blood lead studies were published for only 49 of 137 low- and middle-income countries, and the global child estimate pooled background data from just 34 countries.
Coordination gap
Lead reaches children through paint, pigments, solder, ceramic glazes, jewellery, toys, cosmetics, traditional medicines and plumbing, so controls fall to health, environment, food safety, consumer protection and trade agencies that rarely act together.
Technology gap
Lead already in soil around smelters and mines, and in paint on walls, stays for decades, and remediation of contaminated sites has proven expensive.
Knowledge gap
Of 47 studies on lead and children's learning in a 2025 meta-analysis, only 18 came from low- or middle-income countries, so the size of the harm in the most exposed populations is still estimated largely from richer countries.
Unresolved questions, not vetted breakthroughs. Answering any of them would change what is possible.
In each highly exposed country, how much of children's lead comes from batteries, spices, cookware, paint, soil or water, and can cheap source-tracing methods guide where to act first?
Estimates of lead-related deaths depend on which effects on the heart and blood vessels are counted and on modelled blood lead levels. How large is the toll once more direct measurements and long-term studies from low- and middle-income countries are available?
How strongly does blood lead in the 3 to 10 µg/dL range affect school learning and behaviour where children also face malnutrition and other risks, and how much would lowering it narrow learning gaps?
What mix of regulation, incentives and technology moves used-battery recycling into controlled facilities without simply pushing it to less visible places?
If your home has old paint, avoid dry sanding, scraping or burning it, keep children away during renovation, and use wet cleaning to reduce dust. Choose paints labelled lead-free.
Prefer spices from sellers who test their products, be wary of unusually bright turmeric or chilli powder, and avoid cooking or storing acidic food in traditional glazed ceramics or homemade metal pots of unknown origin.
If a child lives near battery recycling, smelting or old peeling paint, ask a health worker whether a blood lead test is advisable.
When replacing a vehicle or backup battery, hand the old one to a shop or collection point that sends it to a licensed recycling plant rather than to informal buyers.
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World Health Organization, published 2026
WHO fact sheet updated 10 June 2026: health effects, no known safe level, 3.5 µg/dL and 5 µg/dL levels, children's 4–5 times higher absorption, sources of exposure, more than 3.5 million deaths and 71.5 million DALYs in 2023 (IHME, GBD 2023), and 48% of countries with lead paint controls as of January 2024.
World Health Organization, published 2024
Official WHO indicator page and country list: definition of legally binding controls, Yes/No/No data categories from WHO and UNEP surveys, 48% of countries as of 16 January 2024 and 43% as of 31 December 2021.
UNICEF and Pure Earth, published 2020
July 2020 report: around one in three children worldwide, up to 800 million, with blood lead at or above 5 µg/dL, a modelled global estimate.
Ericson B, Hu H, Nash E, Ferraro G, Sinitsky J, Taylor MP, published 2021
Peer-reviewed review of 520 studies (2010–2019) covering 49 of 137 low- and middle-income countries: 632 million children (48.5%) above 5 µg/dL, country means for children from 1.66 to 9.30 µg/dL, and the main sources (battery recycling, mining, e-waste, spice adulteration).
United Nations Environment Programme, published 2021
UNEP press release of 30 August 2021: Algeria last to stop using leaded petrol in July 2021, 117 countries still using it when UNEP's campaign began in 2002, and more than 1.2 million premature deaths prevented per year.
Crawfurd L, Todd R, Hares S, Sandefur J, Silverman Bonnifield R (Center for Global Development), published 2025
Peer-reviewed meta-analysis of 47 studies: about half of children in low-income versus 3% in high-income countries with elevated blood lead, average 5.3 µg/dL across 34 countries, 21% of the rich–poor learning gap, effective low-cost action on spices in Bangladesh and Georgia, missing paint regulation and costly remediation.
DO GOOD International (2026). Ending Childhood Lead Poisoning. Global Challenges. Updated October 15, 2026. https://www.dogood.world/challenges/lead-exposure
For figures, please cite the original sources listed above.