Thursday, October 6, 2011

Why We Need the EPA: Lead Poisoning, Intelligence, and Crime Rates

Hardly a day passes when there is not yet another report warning of the potential harm from chemicals we are adding to our environment. Our children seem to be the most at risk as conditions such as autism become more common. Yet, the Republicans continue to threaten to defund or even eliminate the Environmental Protection Agency (EPA), bellowing claims that environmental regulations increase costs and cause the loss of jobs. These assertions always involve ignoring the total cost of a given action. Jobs lost because of increased costs are easy to count, but the costs incurred because a person became sick, disabled, or died due to exposure to hazardous materials are never considered.

I recently came across an interesting reminder of the decision to phase out lead in gasoline beginning in the 1970s. It must have been a very expensive proposition for the country in the short-term, but it may have been one of our smartest long-term decisions. Children were particularly sensitive to lead exposure; exhibiting developmental disorders, impaired intelligence, and increased aggressive responses. Consider this reference to work performed by Dr. Philip Landrigan.

"In the early 1970s, he studied the IQs of children in El Paso, Texas, where a lead smelter was operating. His results showed 60% of those children had lead poisoning, and that even low-level lead poisoning was causing irreparable harm to their brains. His research prompted Congress to crack down on lead pollution, banning or reducing its use in gasoline, paint and ultimately toys and other products. Those actions have reduced lead poisonings in America by 90%, raised American children's IQs by an average of six points, and injected $200 billion annually into the economy that had been lost to diminished economic productivity."

Can one think of an easier path to raising IQs by six points?

One tends to think of the issue of removing lead from the environment as a thing of importance in the past, but I recently encountered a reminder that the decision made in the 1970s may be a gift that just keeps on giving. The Economist published an article discussing the continuing fall in US crime rates. This graph was provided.





The author was particularly interested in the fact that the crime rate continues to fall even during the current difficult times when so many are in need. A number of suggestions were presented to possibly explain this consistent decline since about 1990. One involved the research of the economist Jessica Wolpaw Reyes.

Reyes published a paper in 2007 that drew a connection between exposure to lead and crime rates. This is from her abstract.

"Childhood lead exposure can lead to psychological deficits that are strongly associated with aggressive and criminal behavior. In the late 1970s in the United States, lead was removed from gasoline under the Clean Air Act. Using the sharp state-specific reductions in lead exposure resulting from this removal, this article finds that the reduction in childhood lead exposure in the late 1970s and early 1980s is responsible for significant declines in violent crime in the 1990s, and may cause further declines into the future."

Violent crimes tend to be committed by young adults. If there was a correlation between crime and lead exposure, then there would be approximately a twenty year time lag between childhood exposure and criminal response. Her analysis produced this graph.





This may not provide conclusive proof of the correlation, but it certainly is suggestive. And it is certainly pleasant to entertain the notion that crimes will continue to diminish in the future.

We need to protect ourselves from the poisoning of our water, food, and air. So protect the EPA and give it more people and money!

1 comment:

  1. Looking at the statistics, it is undeniable that the banning of lead substances in gasoline and toys played a significant role in leading to the increase in mental development among people. In a study conducted in 1979, dentine lead levels were measured in 312 grade school students, and in correlation, the same children were also given neurobehavioral tests. Results showed that behavioral and performance problems were more prevalent among children with increasing dentine lead levels. This is why we should all be cautious in the products we buy in stores and make sure they do not contain this dangerous substance.

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