“There are only a few countries using leaded gasoline, so the majority of the exposures are from lead-based paint, lead battery production and hazardous waste sites,” Trasande said.
As many countries become increasingly industrialized, some, particularly in Africa, have seen spikes in lead exposure over the past three or four decades.
The researchers did not include mild retardation resulting from lead exposure, which is a big problem in Sub-Saharan Africa and parts of Asia, said Ken Jaffe, president and executive director of the International Child Resource Institute, a nonprofit organization that works on children issues around the world.
Jaffe also said it’s hard to estimate IQ point losses without taking into account the state of schools in some of these countries.
“Schools in many countries with high incidences of lead also have poor schools that can be highly abusive to children,” Jaffe said. “I’ve seen schools in Ghana and Zimbabwe where children are beaten for the wrong answer – even in preschool. There are very high dropout rates.”
But, as investors increasingly look to developing countries, putting a dollar amount on environmental exposures could hasten change, Jaffe said.
Previous studies also have looked at economic costs of lead exposure. Every dollar invested in lead paint control results in a $17 to $220 return, according to a 2009 study. Reduced lead exposure in the United States since 1976 has resulted in a $110 billion to $319 billion economic benefit due to higher IQs and worker productivity, according to a 2002 CDC study.
“We’re basically pitting the health of our children versus economic health,” Lanphear said. “Until we can prove it’s cost beneficial to protect kids we won’t do it. It’s really a strange thing for a species to do.”
This article originally ran at Environmental Health News, a news source published by Environmental Health Sciences, a nonprofit media company.