"Lead helps to guard your health."
That was the marketing line that the former National Lead Co. used decades ago to sell lead-based household paints. Yet we now know that lead was poisoning millions of children and permanently damaging their brains. Tens of thousands of children died, and countless millions were left mentally impaired.
One boy, Sam, born in Milwaukee in 1990, "thrived as a baby," according to his medical record. But then, as a toddler, he began to chew on lead paint or suck on fingers with lead dust, and his blood showed soaring lead levels.
Sam's family moved homes, but it was no use. At age 3, he was hospitalized for five days because of lead poisoning, and in kindergarten his teachers noticed that he had speech problems. He struggled through school, and doctors concluded that he had "permanent and irreversible" deficiencies in brain function.
Sam's story appears in "Lead Wars," a book by Gerald Markowitz and David Rosner published this year that chronicles the monstrous irresponsibility of companies in the lead industry over the course of the 20th century. Eventually, over industry protests, came regulation and the removal of lead from gasoline. As a result, lead levels of U.S. children have declined 90 percent in the past few decades, and scholars have estimated that, as a result, children's IQs on average have risen at least two points and perhaps more than four.
So what are the lessons from the human catastrophe of lead poisoning over so many decades? To me, today's version of the lead industry is the chemical industry - companies like Exxon Mobil, DuPont, BASF and Dow Chemical - over the years churning out endocrine-disruptor chemicals that mimic the body's hormones. Endocrine disruptors are found in everything from plastics to pesticides, toys to cosmetics, and there are growing concerns about their safety.
The Endocrine Society, the Pediatric Endocrine Society, the European Society of Pediatric Endocrinology and the President's Cancer Panel have all warned about endocrine disruptors - also referred to as EDC's, for endocrine disrupting chemicals. The World Health Organization and United Nations this year concluded: "Exposure to EDC's during fetal development and puberty plays a role in the increased incidences of reproductive diseases, endocrine-related cancers, behavioral and learning problems, including ADHD, infections, asthma, and perhaps obesity and diabetes in humans."
Alarm about endocrine disruptors once was a fringe scientific concern but increasingly has moved mainstream. There is still uncertainty and debate about the risk posed by individual chemicals, but there is growing concern about the risk of endocrine disruptors in general - particularly to fetuses and children. There is less concern about adults.
Scientists are also debating whether the old toxicological models are appropriate for chemicals that mimic hormones and thus may trigger bodily changes, especially in fetuses and children.
These are the kinds of threats that we in journalism are not very good at covering. We did a wretched job covering risks from lead and tobacco in the early years; instead of watchdogs, we were lap dogs.
One common thread is industry's greed, duplicity and powerful lobbying in Washington and around the country. The chemical industry spent $55 million lobbying last year, twice the figure a decade earlier, according to the Center for Responsive Politics.
The Chicago Tribune last year documented how the chemical industry created a fake movement for flame retardants in furniture, supposedly to prevent fires; in fact, flame retardants don't reduce fires but do contain endocrine disruptors that may be harmful to our children.
This summer 18 scientists wrote a scathing letter railing against European Union regulations of endocrine disruptors. That underscored the genuine scientific uncertainty about risks - until Environmental Health News showed that 17 of the 18 have conflicts of interest, such as receiving money from the chemical industry. Meanwhile, more than 140 other scientists followed up with their own open letters denouncing the original 18 and warning that endocrine disruptors do indeed constitute a risk.
Andrea C. Gore, the editor of Endocrinology, published an editorial asserting that corporate interests are abusing science today with endocrine disruptors the way they once did with lead: for the "production of uncertainty."
She added that the evidence is "undeniable: that endocrine-disrupting chemicals pose a threat to human health."
When scientists feud, it's hard for the rest of us to know what to do. But I'm struck that many experts in endocrinology, toxicology or pediatrics aren't waiting for regulatory changes. They don't heat food in plastic containers, they reduce their use of plastic water bottles, and they try to give their kids organic food to reduce exposure to pesticides.
So a question for big chemical companies: Are you really going to follow the model of tobacco and lead and fight regulation every step of the way, once more risking our children's futures?
Nicholas Kristof is a columnist for The New York Times.