Dr. Philip Landrigan linked the use of lead in gas and paint to lowered IQ in children in the 1970s. Now he's sounding the alarm about the dangers of pesticides and plastics. Photo: Courtesy Philip Landrigan
In the 1970s, Philip J. Landrigan conducted groundbreaking work linking lead in gasoline and paint to a lowered IQ in children exposed to it.
His transformative work as an epidemiologist and pediatrician eventually resulted in the elimination of lead from paints and gasoline, resulting in a 90% reduction in childhood lead poisoning and a 5% increase in the average child’s IQ.
Since that time, Dr. Landrigan has turned his focus on other dangerous substances in our environment. In the 1980s, his research revealed that significant concentrations of pesticides in baby food were putting infants at risk. That discovery led to the 1996 Food Quality Protection Act. Most recently, he has co-chaired The Lancet Commission on Pollution in Health, which found that pollution is responsible for an estimated 9 million deaths annually. He’s also co-chaired the Minderoo-Monaco Commission on Plastic and Human Health, finding that plastics cause human health impacts and harm at every phase of the plastics production cycle.
Recently, Dr. Landrigan visited CLF to discuss how the chemicals in our daily lives compromise our health. An article he co-authored in the New England Journal of Medicine this year calls for improved laws to protect our children against these toxic chemicals. Here, we have adapted his talk into a Q and A format edited for length and clarity.
CLF: There have been remarkable improvements in the health of Americans over the last 100 years. Life expectancy has doubled thanks to vaccines, antibiotics, and improved nutrition. So, why are the rates of some diseases still rising in children?
Dr. Landrigan: A factor that threatens to degrade [improving life expectancy] is the rising rate of chronic noncommunicable diseases in American kids, even as rates of smallpox have gone to zero, scarlet fever has gone to almost zero, polio has almost disappeared. Since the 1950s, a whole suite of chronic noncommunicable diseases have been on the rise.
Childhood asthma has approximately tripled in this time. The death rate from childhood cancer has gone down, thanks to advances in treatment, but the incidence rate, the number of new cases of cancer per thousand children, has gone up by approximately 35% since the early 1970s. Childhood leukemia and childhood brain cancer, the two most common forms of childhood cancer, and testicular cancer, the most common form of cancer in adolescence, have all gone up quite remarkably in incidence since that time.
Childhood obesity has approximately quadrupled in this country from 5% in the 1970s to just shy of 20% today. And then, of course, the whole suite of neurodevelopmental disorders – everything from mild [intellectual disabilities] to attention deficit disorder, ADHD, autism spectrum disorder – have all gone up. Approximately one child in six born in this country has some form of neurodevelopmental disorder and autism, which is the one that gets the most attention. About one child in 36 is on the spectrum. So, all of those chronic diseases are on the increase.
CLF: You say that multiple factors play a role in these increases, including better diagnosis of neurodevelopmental disabilities.
Dr. Landrigan: Better diagnosis accounts for a part of the reported increase, especially for neurodevelopmental disorders, but that does not account for the increase in asthma. It doesn’t account for the increase in childhood cancer or obesity. Those are all objectively diagnosed, objectively measured outcomes. And they’re absolutely on the increase. Those are the grim patterns of disease.
CLF: Why is this happening?
Dr. Landrigan: Some of it is changes in diet, some of it is changes in lifestyle. Children today are certainly more sedentary than they were a generation ago. That certainly plays into the increasing rates of obesity. But a big change that is insufficiently recognized is the extraordinary growth in synthetic manufactured chemicals over the past 75 years.
CLF: You point to the massive growth of the fossil-fuel-based chemical manufacturing industry in this country since World War II as a factor. How would that play a role?
Dr. Landrigan: There’s been an aggregate growth of about 250-fold in the manufacture of chemicals and plastics since [the 1950s]. These chemicals are now everywhere in the environment.
They’re in the air, they’re in the water, they’re in food. People have gone to the farthest corners of the planet, to the Mariana Trench six miles below the Pacific, to the glaciers and the Himalayas, to the Arctic and the Antarctic – and they find toxic chemicals and microplastic particles that act as the vectors for these chemicals. They find them pretty much everywhere they look, without exception. They’ve become ubiquitous on the planet, and they’re in us. Every single one of us has at least 200 toxic chemicals in our bodies, admittedly in small quantities, but they’re there. The evidence has been building now since the 1970s that these manufactured chemicals cause disease.
CLF: What’s the evidence?
Dr. Landrigan: In the 70s, we took children who had elevated levels of lead in their blood, put them through IQ testing, testing of their reflexes, testing of their motor function. We were able to show that these children had damage to their brains, damage to their nervous systems, even at lead levels in the blood that caused no obvious symptoms.
Over the years, that work has continued to progress, and a newer generation has taken up the baton and applied even more sophisticated neuropsychological testing tools to evaluate children. We’ve come to realize that even the very lowest levels of lead in the blood cause neuropsychological damage, brain injury, reduced IQ, and short attention spans.
Once we’d opened up that line of research and opened people’s eyes to the possibility that low levels of exposure to chemicals could cause disease, people started looking at lots of other chemicals to see if they could impact brain development, reproductive function, hormonal function, the risk of cancer, and the risk of heart disease.
The passage of the Food Quality Protection Act in 1996 triggered decisions by the EPA and the National Institutes of Health to invest heavily in research in environmental pediatrics. In other words, research specifically designed to study the impacts of chemicals on children’s health.
CLF: You mention that the most important class of studies being done are long-term epidemiologic studies tracking women’s exposure to toxic chemicals during pregnancy and evaluating their babies periodically, right up through adulthood. What insights have come out of this work?
Dr. Landrigan: The first is that infants and children are far more sensitive to toxic chemicals than adults. The second is that exposure to toxic chemicals in early life can cause not only disease in infancy and childhood but can also lay the seeds for disease that shows up decades later.
So, for example, it’s now known that exposure to the plastic chemical BPA, (Bisphenol A) early in life can damage the liver, interfering with the metabolism of cholesterol in the body. That results in elevated levels of cholesterol and other bad lipids in the bloodstream, increasing the risk for hypertension, obesity, and ultimately, heart disease and stroke.
CLF: In your New England Journal Article, you mention a long list of chemicals that can damage infants and children, including, notably, pesticides.
Dr. Landrigan: We now know full well from high-quality studies that these chemicals cause long-term brain damage in children.
CLF: And yet, harmful pesticides like neonicotinoids, which we know are neurotoxic, are still in wide use today, along with plastic chemicals like phthalates. Why?
Dr. Landrigan: The answer is that chemical safety law in this country, and most countries around the world, is terribly weak. And right now, the Trump administration is working to weaken these laws still further by dismantling the EPA unit that evaluates chemicals for toxicity.
They want to further shred the already weak protections that exist. And the result is that chemicals come on the market with essentially no pre-market testing for safety or toxicity.
So, of the 200 to 300 chemicals in all of us, most – 80% plus or minus – have never been tested for safety or toxicity. Nobody has a clue what they might be doing to us.
And we have even less knowledge about what they might be doing to infants in the womb and young children who are more sensitive to toxic chemicals than we adults.
The fundamental flaw in the Toxic Substances Control Act, as it’s actually executed, is that it presumes that chemicals are safe until they’re proven guilty. Chemicals actually get better protection under the law than most criminal defendants. And they have better lawyers.
CLF: What needs to change?
Dr. Landrigan: There needs to be absolutely fundamental revamping of the Toxic Substances Control Act. We also talk about the need for a global chemicals treaty.
Maybe it could be modeled on the global plastics treaty, which is currently being negotiated under UN auspices. That would require testing of chemicals in global commerce.
