Lead is a potent neurotoxin; exposure to lead can lead to reduced IQ and cognitive problems, among other ills. In the 1970s, lead was removed from household paint. And in the 1990s, we phased out leaded gasoline. In recent years it seemed like we had almost won the public health battle against lead exposure.
Sadly, Joel Schwartz of the Harvard School of Public Health recently delivered a sobering message: while cases of lead poisoning are down, new research indicates that persistent low levels of lead exposure are causing serious health impacts, among them attention deficit disorder, psychiatric disorders, and hypertension.
Chronic lead exposure has also been linked to an increased risk of dementia. Throughout our lives, our skeletons accumulate lead. Later in life, when our bones de-mineralize and lose calcium—lead is released into our bloodstream, where it impacts brain function.
Schwartz has urged the scientific community to, “Stop thinking about the problem as a small number of people who have an acute exposure, and start thinking about the problem as a large number of people who have a chronic exposure.”
The primary route of persistent lead exposure is through breathing combustion particles in the air. Concentrations well below current standards are associated with adverse health effects.
Coal-burning power plants are among the worst offenders when it comes to airborne lead particles. And air pollution doesn’t recognize borders. Lead particles from China have been found in rainfall in Santa Cruz, California.
Like climate change, chronic lead exposure is a problem we need to tackle as a global community.
Harvard School of Public Health
Photo, taken on March 5, 2010, courtesy of Flickr.
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