A recent study has found that children exposed to lead at a young age are more likely to commit crimes as juveniles and adults. That has big implications for the future of New Orleans and other areas affected by Hurricane Katrina, since lead was one of the contaminants found at dangerously elevated levels in some neighborhoods after the storm, and since it is also being released into the environment anew as damaged housing stock with lead-tainted paint gets torn down and renovated.

The research was done by Rick Nevin, an independent economic consultant and senior advisor for the National Center for Healthy Housing. He compared trends in childhood lead exposure to crime rate trends over several decades in nine countries: the United States, Britain, Canada, France, Australia, Finland, Italy, West Germany and New Zealand.

In every country, Nevin found that the greater the lead exposure, the higher the crime rate. And in examining crimes data in U.S. cities, he found that murder is especially associated with more severe childhood lead poisoning.

"The research shows a clear link between lead exposure and crime, not just in this country but eight others as well," said NCHH Executive Director Rebecca Morley. "Nevin's work demonstrates the need for the U.S. Environmental Protection Agency to finalize rules to help prevent childhood exposure to lead during the renovation, painting and remodeling of older homes."

National health and housing advocacy organizations are calling on the EPA to issue a regulation that has been delayed for nearly 11 years. The regulation would protect children from lead poisoning during home renovation and remodeling. Similar requirements have been in place since 2001 for federally-assisted housing, but other housing remains at risk. The groups also called on EPA to strengthen the requirements it issued in proposed form more than a year ago.

In the wake of Hurricane Katrina, high levels of lead were detected in 14 New Orleans neighborhoods. State environmental officials said that the contamination was there before the storm, but that's little consolation to the people who have to live with it. Indeed, lead contamination expert Howard Mielke of Xavier University told the Times-Picayune that lead contamination affected as much as 40 percent of the city before Katrina, and as many as 25 percent of children living in New Orleans' predominantly African-American urban neighborhoods suffered from lead poisoning.

While the storm itself may not have dramatically worsened the contamination, it certainly didn't help by churning up sediments from polluted waterways and depositing them on land. And in the storm's aftermath, the widespread destruction of older homes with lead paint followed by demolition and renovation presents a risk for further lead poisoning of the environment. That's one reason the U.S. Department of Housing and Urban Development offered workshops to help renovators avoid lead hazards.

However, the government failed to take additional, relatively inexpensive steps to ease the city's lead burden. Shortly before Katrina struck, Mielke completed a HUD-funded lead abatement project that involved covering lead-contaminated yards with clean soil. Mielke estimated it would cost between $225 million and $290 million to expand the program to New Orleans neighborhoods with the highest lead levels, and the city's evacuation after the storm provided a perfect opportunity to get that work underway.

But the government chose not to take the preventive approach. As a result, citizens will continue to pay the ongoing costs associated with lead poisoning, which include special education programs, medical care and intensified crime-fighting efforts. And these costs are considerable: A 2002 study put the estimated costs of pediatric lead poisoning in the United States as a whole at $43.4 billion.

(This post was changed from the original on July 18, 2007 to correct the date of the study mentioned in the last sentence.)