When Did Lead Become Dangerous? How Our Understanding of Risks Changed Over Time

Aug 23, 2017

Bill Haggard is the mayor of Herculaneum, Missouri, a town of 4,000 about a 30 minute drive south of St. Louis. He’s also the fire chief, president of the historical society and a retired teacher, among other distinctions, although he identifies first as a “lifelong resident.”

For more than a century this town was built up around the lead smelter that sat along the Mississippi River. Today, though, most of the houses remaining in the hollowed out center of town are marked in spray paint with a bright orange ‘X.’

“If they have an ‘X’ on them they’re coming down,” Haggard says while driving by houses slated for demolition.

Lead has long been known to be harmful. In the 17th century, for example, putting lead sugar into wine was punishable by death in some germanic states. Still, even as lead poisoning became pervasive during the industrial revolution there were towns like Herculaneum dedicated solely to the production of the metal. Exposure was just a part of doing business.

“There was this whole notion that when you took a job you assume the risks of the job,” says David Rosner, co-director of the Center for the History & Ethics of Public Health at Columbia University. 

“So when workers were moving into factories and into mines, a lot of people took this to mean that the responsibility for danger resided with the worker.”

Perceptions began to shift in the early 20th century, however, as researchers around the world noticed that children were starting to show the same symptoms of lead poisoning that were previously only seen in industrial workers—a trend caused by the use of lead-based paint in homes.

“A consciousness emerged that these children certainly hadn’t been responsible for getting poisoned,” Rosner says.

Children also figured prominently in Herculaneum as the town became a case study in America’s shifting attitudes and regulations on lead contamination.

A Case Study in Lead

Mayor Bill Haggard says the the lead smelter was always integrated into the town. In the winter the smelter would give out slag—the waste created in the smelting process—to use to melt the ice on the town’s roads and driveways.

Herculaneum Mayor Bill Haggard stands in front of Herculaneum's City Hall.
Credit Bram Sable-Smith / KBIA/Side Effects Public Media

“It works great. Better than anything out there,” Haggard says.

Children used to play on the slag pile, and they’d also walk down into the plant to eat lunch with their fathers or to pump up their bike tires or even to take showers.

“There was all this good I guess that just covered up the bad,” Haggard says.

But as time went on, the effects of lead contamination in the town became hard to ignore. In 1988 the Doe Run company, who ran the town’s smelter, was fined for 177 violations of workplace lead standards. In the late 1990’s some concerned parents got the Missouri Department of Natural Resources to test the dust covering the town’s streets and found it was 30 percent lead.

By that time researchers like Bruce Lanphear of Simon Fraser University had started to link even low levels of lead exposure with drops in children’s IQ scores and behavior problems like ADHD.

“This is not just acting out,” Lanphear says, “this is when kids are impaired, when they can’t learn. Half the kids with ADHD also meet the definition of having a learning disorder.”

Contrary to conventional wisdom, Lanphear says the health problems associated with lead are not proportional to the amount of exposure to the metal. The ill health effects are still present in children today—even though they’re exposed to significantly lower lead levels than children just 30 years ago.

“We assume that toxic chemicals or pollutants are safe below certain levels. What we are finding for lead is that there aren’t any safe levels,” Lanphear says.

That understanding was the nail in the coffin for the Herculaneum smelter.

For years, regulating bodies like the EPA would put new restrictions on the lead smelter, which would try to match them. In 2002 the company agreed to buy out more than 150 lead-contaminated houses, hence the homes Mayor Bill Haggard pointed out that were marked with an ‘X.’ By 2010 the company decided the only feasible option was to close down the smelter for good.

“I never thought I’d live to see that day,” Haggard says.

Without the smelter or a new industry in town, Haggard worries Herculaneum could be destined to become a bedroom community for nearby St. Louis.

“There will never be another industry” like lead, Haggard says, “it’s just not possible.”