OT but health related - Research Links Lead Exposure, Criminal Activity

[Guest guest]

Data May Undermine Giuliani's Claims

By Shankar Vedantam

Washington Post Staff Writer

Sunday, July 8, 2007; Page A02

Rudy Giuliani never misses an opportunity to remind people about his track

record in fighting crime as mayor of New York City from 1994 to 2001.

" I began with the city that was the crime capital of America, " Giuliani, now

a candidate for president, recently told Fox's Wallace. " When I left,

it was the safest large city in America. I reduced homicides by 67 percent.

I reduced overall crime by 57 percent. "

A recently released study concludes that there is a strong association

between preschoolers' blood lead levels and crime rates 19 years later, when

the preschoolers grow up. Declines in lead levels in several industrialized

countries corresponded with later drops in crime rates, the study says.

and a range of scientific research has emerged in recent years to show that

the mayor deserves only a fraction of the credit that he claims. The most

compelling information has come from an economist in Fairfax who has argued

in a series of little-noticed papers that the " New York miracle " was caused

by local and federal efforts decades earlier to reduce lead poisoning.

The theory offered by the economist, Rick Nevin, is that lead poisoning

accounts for much of the variation in violent crime in the United States. It

offers a unifying new neurochemical theory for fluctuations in the crime

rate, and it is based on studies linking children's exposure to lead with

violent behavior later in their lives.

What makes Nevin's work persuasive is that he has shown an identical,

decades-long association between lead poisoning and crime rates in nine

countries.

" It is stunning how strong the association is, " Nevin said in an interview.

" Sixty-five to ninety percent or more of the substantial variation in

violent crime in all these countries was explained by lead. "

Through much of the 20th century, lead in U.S. paint and gasoline fumes

poisoned toddlers as they put contaminated hands in their mouths. The

consequences on crime, Nevin found, occurred when poisoning victims became

adolescents. Nevin does not say that lead is the only factor behind crime,

but he says it is the biggest factor.

Giuliani's presidential campaign declined to address Nevin's contention that

the mayor merely was at the right place at the right time. But

Bratton, who served as Giuliani's police commissioner and who initiated many

of the policing techniques credited with reducing the crime rate, dismissed

Nevin's theory as absurd. Bratton and Giuliani instituted harsh measures

against quality-of-life offenses, based on the " broken windows " theory of

addressing minor offenses to head off more serious crimes.

Many other theories have emerged to try to explain the crime decline. In the

2005 book " Freakonomics, " D. Levitt and J. Dubner said the

legalization of abortion in 1973 had eliminated " unwanted babies " who would

have become violent criminals. Other experts credited lengthy prison terms

for violent offenders, or demographic changes, socioeconomic factors, and

the fall of drug epidemics. New theories have emerged as crime rates have

inched up in recent years.

Most of the theories have been long on intuition and short on evidence.

Nevin says his data not only explain the decline in crime in the 1990s, but

the rise in crime in the 1980s and other fluctuations going back a century.

His data from multiple countries, which have different abortion rates,

police strategies, demographics and economic conditions, indicate that lead

is the only explanation that can account for international trends.

Because the countries phased out lead at different points, they provide a

rigorous test: In each instance, the violent crime rate tracks lead

poisoning levels two decades earlier.

" It is startling how much mileage has been given to the theory that abortion

in the early 1970s was responsible for the decline in crime " in the 1990s,

Nevin said. " But they legalized abortion in Britain, and the violent crime

in Britain soared in the 1990s. The difference is our gasoline lead levels

peaked in the early '70s and started falling in the late '70s, and fell very

sharply through the early 1980s and was virtually eliminated by 1986 or '87.

Research Links Lead Exposure, Criminal Activity

" In Britain and most of Europe, they did not have meaningful constraints [on

leaded gasoline] until the mid-1980s and even early 1990s, " he said. " This

is the reason you are seeing the crime rate soar in Mexico and Latin

America, but [it] has fallen in the United States. "

Lead levels plummeted in New York in the early 1970s, driven by federal

policies to eliminate lead from gasoline and local policies to reduce lead

emissions from municipal incinerators. Between 1970 and 1974, the number of

New York children heavily poisoned by lead fell by more than 80 percent,

according to data from the New York City Department of Health.

Lead levels in New York have continued to fall. One analysis in the late

1990s found that children in New York had lower lead exposure than children

in many other big U.S. cities, possibly because of a 1960 policy to replace

old windows. That policy, meant to reduce deaths from falls, had an

unforeseen benefit -- old windows are a source of lead poisoning, said Dave

s of the National Center for Healthy Housing, an advocacy group that is

publicizing Nevin's work. Nevin's research was not funded by the group.

The later drop in violent crime was dramatic. In 1990, 31 New Yorkers out of

every 100,000 were murdered. In 2004, the rate was 7 per 100,000 -- lower

than in most big cities. The lead theory also may explain why crime fell

broadly across the United States in the 1990s, not just in New York.

The centerpiece of Nevin's research is an analysis of crime rates and lead

poisoning levels across a century. The United States has had two spikes of

lead poisoning: one at the turn of the 20th century, linked to lead in

household paint, and one after World War II, when the use of leaded gasoline

increased sharply. Both times, the violent crime rate went up and down in

concert, with the violent crime peaks coming two decades after the lead

poisoning peaks.

Other evidence has accumulated in recent years that lead is a neurotoxin

that causes impulsivity and aggression, but these studies have also drawn

little attention. In 2001, sociologist B. Stretesky and criminologist

Lynch showed that U.S. counties with high lead levels had four times

the murder rate of counties with low lead levels, after controlling for

multiple environmental and socioeconomic factors.

In 2002, Herbert Needleman, a psychiatrist at the University of Pittsburgh,

compared lead levels of 194 adolescents arrested in Pittsburgh with lead

levels of 146 high school adolescents: The arrested youths had lead levels

that were four times higher.

" Impulsivity means you ignore the consequences of what you do, " said

Needleman, one of the country's foremost experts on lead poisoning,

explaining why Nevin's theory is plausible. Lead decreases the ability to

tell yourself, " If I do this, I will go to jail. "

Nevin's work has been published mainly in the peer-reviewed journal

Environmental Research. Within the field of neurotoxicology, Nevin's

findings are unsurprising, said Ellen Silbergeld, professor of environmental

health sciences at s Hopkins University and the editor of Environmental

Research.

" There is a strong literature on lead and sociopathic behavior among

adolescents and young adults with a previous history of lead exposure, " she

said.

Two new studies by criminologists Rosenfeld and F. Messner

have looked at Giuliani's policing policies. They found that the mayor's

zero-tolerance approach to crime was responsible for 10 percent, maybe 20

percent, at most, of the decline in violent crime in New York City.

Nevin acknowledges that crime rates are rising in some parts of the United

States after years of decline, but he points out that crime is falling in

other places and is still low overall by historical measures. Also, the

biggest reductions in lead poisoning took place by the mid-1980s, which may

explain why reductions in crime might have tapered off by 2005. Lastly, he

argues that older, recidivist offenders -- who were exposed to lead as

toddlers three or four decades ago -- are increasingly accounting for much

of the violent crime.

Nevin's finding may even account for phenomena he did not set out to

address. His theory addresses why rates of violent crime among black

adolescents from inner-city neighborhoods have declined faster than the

overall crime rate -- lead amelioration programs had the biggest impact on

the urban poor. Children in inner-city neighborhoods were the ones most

likely to be poisoned by lead, because they were more likely to live in

substandard housing that had lead paint and because public housing projects

were often situated near highways.

Chicago's Homes, for example, were built over the Dan

Expressway, with 150,000 cars going by each day. Eighteen years after the

project opened in 1962, one study found that its residents were 22 times

more likely to be murderers than people living elsewhere in Chicago.

Nevin's finding implies a double tragedy for America's inner cities:

Thousands of children in these neighborhoods were poisoned by lead in the

first three quarters of the last century. Large numbers of them then became

the targets, in the last quarter, of Giuliani-style law enforcement

policies.