It’s in your lipstick, pencil and front garden, and scientists now claim to have proved that the metal element lead causes violent crime. Wide-ranging research into a "public health catastrophe" showed people exposed to lead as children are more likely to offend as adults.
Using data from 90 US cities since the 1950s, researchers at the University of Tulane, New Orleans, found that violent crimes rates mirrored lead emissions. They rose sharply around 20 years after the introduction of leaded gasoline and began to fall the same interval after it was phased out in the 1970s.
Crime rates remained high only in cities where emissions remained high. The correlation also applied at a neighborhood level and the data is even being used by local police forces.
Researchers balanced the findings against social factors such as income, education and race, but the results remained consistent. The research was "carefully controlled," said independent toxicologist Professor Alastair Hay of the University of Leeds, who was "convinced" by the conclusion.
The link is supported by a 2007 academic study which found close ties between lead and crime levels in 14 nations across the world. A 2007 behavioral study found children exposed to lead were more often arrested for violent crimes and "demonstrated association between developmental exposure to lead and adult criminal behavior."
The US Environmental Protection Agency advises that any contact with the toxic element is dangerous. Exposure attacks the brain’s neuron connections, causing lower IQ, Attention Deficit Disorder and aggression.
Many cities still suffer with lead-contaminated soil.
"In New Orleans, play areas for children are effectively hazardous waste sites," Tulane study author and toxicologist Dr. Howard Mielke told Metro.
Mielke supports a nationwide ‘clean soil’ campaign, which would cost billions of dollars but offset the "cost to society of lead poisoning – in learning, behavioral problems, violence and incarceration."
New civil society groups such as the Lead Safe America Foundation are pursuing an awareness and reparation campaign, supported by lead-poisoning victims. Mielke argues that oil companies should fund this on the 'polluter pays' principle, and accuses them of "covering up" the danger of lead.
The hidden menace
Lead can be found in many forms around the home, including...
- Walls: Homes built before 1980 commonly used lead paint
- Soil: Contains trace lead and concentration higher in urban areas
- Containers: Pottery and crystal, especially from Latin America, can be lead-glazed
- Cosmetics: All lipstick contains lead
- Toys: In 2010, Fisher-Price recalled near 11 million toys after Chinese vendor used lead-based paint to coat them