Childhood lead exposure leads to billions in productivity losses in low- and middle-income countries
A new study quantifies the large productivity losses in low- and middle-income countries (LMICs)—billions of dollars’ worth—that can be attributed to lead exposure in children.
The study was published July 3 in the journal Health Economics, Policy and Law. Co-authors included Harvard T.H. Chan School of Public Health’s Mary Jean Brown, adjunct associate professor of social and behavioral sciences, and Bret Ericson of New York University.
The study builds on previous studies that calculated the economic cost of childhood lead exposure by quantifying the effect of reduced cognitive capacity on economic productivity over a person’s lifetime. Lead’s harms can be severe. There is no known safe blood lead level for children, who are particularly vulnerable. Long-term impacts can include decreased IQ and behavioral challenges that limit academic and professional success. Higher levels of lead exposure cause major intellectual disability, seizure disorders, and death.
For the new study, researchers conducted a larger systematic review of blood lead level data than previous studies, drawing data from 388 publications. They were also able to look at a larger group of countries by interpolating blood lead level data for those that lacked such information. Using these data, they then calculated IQ losses—and subsequent lifetime productivity losses—for a one-year cohort of five-year-old children—all children who turned five in 2019—in 121 LMICs.
They found that lifetime productivity losses related to child blood lead levels ranged from $305 billion to $499 billion for each one-year cohort of five-year-olds. Productivity losses as a share of GDP were lowest in East Asia and the Pacific, ranging from 0.7-1.1%, and highest in sub-Saharan Africa, ranging from 2.6-4.2%. However, in absolute terms, productivity losses in East Asia and the Pacific were far larger than in other regions, accounting for nearly 38% of the total losses among all LMICs. The results in East Asia and the Pacific were driven largely by the values for one country—China—which accounted for roughly 50% of IQ points lost and 76% of absolute productivity losses in the region.
The authors called their estimates of lead-related productivity losses conservative, noting that adult lead exposure—known to damage the cardiovascular system—can also result in loss of productivity and high healthcare costs for countries. “By estimating only those productivity costs associated with pediatric lead exposure, the present study vastly underestimates lead’s overall impact,” the authors wrote.
Childhood lead exposure doesn’t receive nearly enough attention—given its outsized impact—in large part because of the lack of comprehensive and publicly available information, according to the authors. They said it’s critical to develop a central repository of data on blood lead levels, as well as to set reporting standards to improve data quality. Improving the evidence base could help identify and remediate lead sources, they said, and help with monitoring and evaluating efforts aimed at eliminating lead exposure worldwide.
Read the study: Lead-attributable productivity losses in low- and middle-income countries
