Press Release

Lead poisoning to blame for more than 20 percent of the gap in learning levels between children in rich and poor countries

London—Half of all children in low- and lower-middle income countries have elevated blood lead levels, and new research finds this could account for more than 20 percent of the learning gap between children in rich and poor countries.

Researchers at Washington- and London-based think tank, The Center for Global Development (CGD), reviewed 47 studies across 17 countries on the link between lead and children’s cognitive development, to estimate the effect of lead exposure on learning outcomes.

The study concludes that exposure to lead likely has a large impact on children’s learning levels, and the authors note that lead receives fairly limited attention from education policymakers given its potentially large role in explaining education outcomes.

Lee Crawfurd, one of the report’s authors and a Research Fellow in CGD’s education programme commented:

“We wanted to explore the link between two big-picture facts about education and health in the developing world. One—fewer than half of ten-year-olds in low-income countries can read a sentence. And two—half of all children in low- and lower-middle income countries still have elevated levels of lead in their blood.

“Our research shows that if we reduced child lead poisoning in developing countries to the low levels found in rich countries, it could have a huge impact on children’s learning. The likely effect on learning is comparable to some of the most celebrated education interventions, like “teaching at the right level” or structured pedagogy.”

The researchers highlight that addressing lead poisoning is tractable: there are large-scale, low-cost policy reforms which can reduce lead exposure—like improved regulation of the lead paint and lead battery industries—which could have a meaningful impact on global learning levels at reasonable cost.

The study’s authors note that investing in lead reduction offers a promising agenda for governments and foreign aid donors interested in promoting education outcomes.

Susannah Hares, director of CGD’s education programme and another study author said:

“This research makes it clear that lead poisoning is limiting children’s learning and their life chances. Because this is happening outside of schools, the education implications of lead exposure tend to fall through the cracks between environment, health, and education ministries. We hope this research will encourage people to look beyond those policy silos.”