The systematic lead poisoning of American citizens, and particularly of children, is a national shame and tragedy. Lead is a naturally occurring element, a heavy, soft metal with the atomic number 82, that has been used for millennia for such purposes as bullets, cosmetics, and plumbing, the Latin etymology of which provides the elemental symbol Pb. Lead is inherently toxic to humans, legendarily so. It has been blamed for the fall of the Roman Empire. This seems a dreadful irony, considering how it has undermined the intelligence of the population of the United States, which many people consider an inheritor of the Roman empiric legacy. Lead poisoning causes a multitude of symptoms, not all of which are immediately apparent. Lead primarily causes neurological problems like learning disabilities, IQ deficits, and hyperactivity. But it can also cause anemia, hearing problems, and slowed growth. In extreme cases, lead poisoning can cause seizures, coma, and death (EPA, 2014). My dog from childhood died this way – horribly – after ingesting paint chips when we repainted the porch on our 1914 house in 1982. Apparently, lead paint has a sweet taste that made this appetizing to our dog – Razzmatazz. I will never forget going off to school on a beautiful day during my Freshman year in High School in Canton, Illinois as my dog lay dying, in convulsions from the lead. She was dead by the time I arrived home.
But lead exposure in the United States is also a success story, a story told by the CDC – Centers for Disease Control and Prevention in Atlanta – that offers the most important and most encouraging counterpoint to the issue of toxic contamination. A picture is indeed worth a thousand words in this case, as seen below. From 1976 to 1980, during our own childhoods, 88.2% of children 1-5 years old had above the level of lead in the blood then thought to cause harm to the brain (≥10 micrograms of lead per deciliter of blood). When lead was banned from gasoline and paint, blood lead levels dropped precipitously. The most recent data show only 1.4% of children at that level. Think about that! Even in Roman times, there were anecdotes about the dangers of lead; safety concerns were raised about lead almost as soon as it was put in gasoline and paint. Though the League of Nations took lead out of paint in 1922, it was not until 1976 that lead was banned in U.S. paint; phase-out of lead in gasoline began in 1972, though it was not completed until 1991. Immediately as these changes were made, blood lead levels changed as well. The moral of this story is that we can make different policies and save children’s lives. Better decisions do indeed lead to dramatically better outcomes. The economic benefits of decreased lead levels have been estimated at $110-319 billion per birth cohort in the 2000s, compared to the 1970s (Grosse et al. 2002). There were huge gains in IQ as well. The graph does not show the personal impact of this decision, however, and it would be impossible for it to do so in a positive way: there is no way to tell the story of children not disabled for life by lead poisoning now. Aside from the occasional poisoning via lead jewelry, like the child who died recently in Minnesota from swallowing a small metal charm, the accounts of the children who were killed or disabled by lead in the past are mostly relegated to the dust of historical obscurity. Of course, children in Nigeria still die from lead poisoning by the hundreds, a result of gold mining in the area (Plumlee 2013). But the important point is that public policy and the actions of corporations and individuals have real effects on others, particularly on vulnerable children. In ten years, I hope to see a similar graph for pesticides and other environmental chemicals, with the concomitant decline in childhood leukemia and other maladies. At the moment, while the harms of lead are widely recognized, people systematically poison their children by treating their lawns and homes with a multitude of toxic chemicals.
Figure 1. Percentage of children 1-5 years old in the U.S. population
with elevated blood lead levels (≥ 10 μg/dL) (Jones et al. 2009).
The same lesson is repeated with nicotine. Blood levels of cotinine, a metabolite of nicotine, have been reduced 70% in non-smokers over the last 15 years, a result, no doubt, of the public health campaign against smoking and laws that restrict smoking in public places (CDC 2009). Again, public policy and individual action do make a difference. Non-smokers decided that they had a right to breathe clean air, and though we will never be able to put names to those who evaded death by lung cancer or emphysema or low birth weight, we know, statistically, that many lives were indeed saved. At one time, those who asked not to be contaminated by second-hand smoke were seen as presumptuous and rude; now, such expectations are usual and accepted. Now it is the smokers who are seen as rude if they blow their carcinogens in others’ direction. People are felt to have a right to clean air, at least when it comes to smoking; it is hard to overstate the importance of this cultural change, which went hand-in-hand with increased regulation. Restaurants and bars no longer allow smoking inside. People who use pesticides outside that leave their private yards and go into other people’s yards and affect other people’s health – or workplaces or schools or cities that impose this burden without permission or notification – are exactly analogous.
Another important plot point in this story is that the harms caused by lead and tobacco were known long, long before companies putting lead in children’s toys or manipulating nicotine levels would admit to what they were doing. Tobacco and paint companies complained about regulations, obfuscated the truth, pressured regulators, and even paid researchers to construct misleading or false science. Naomi Oreskes and Erik Conway, in Merchants of Doubt: How a Handful of Scientists Obscured the Truth on Issues from Tobacco Smoke to Global Warming, show how intentionally this was done, in some cases by the same individuals over a period of years, on issues ranging from acid rain to pesticides to climate change (2011). In an effort to absolve themselves from blame, manufacturers argued that it was the choice of the consumer whether to use the paint or to smoke cigarettes. For some people, there was a free choice to smoke, or to be exposed to lead paint, but that was not true for everyone; it was not true for the children. And look at the consequences.
While the graph above does seem to show a success, there has been another plot twist. Lead is xenobiotic – foreign to and hostile to life – and ideally, no person should have any lead in their bodies. Whereas damage was once thought to occur above 10µg Pb/dL blood, recent studies show that harm occurs at only 5µg Pb/dL blood, or even less (EPA, 2014; Schnur, 2014). The legacy of lead continues to haunt us. Research shows that chronic but low (1.02-5.00 µg Pb/dL blood) levels of lead are associated with obesity (Kim et al. 1995) and neural deficits. By contrast to the 10µg Pb/dL blood level, 2.6% of children were measured at 5µg Pb/dL blood in the 2007-2010 NHANES (CDC, 2013).
Everyone should take these stories to heart. Recently, I began to think about our family’s lead exposure. We have always carefully considered routes of exposure. We live in a much older home – 1843 – and so we knew it could be a problem, but we never have painted the house while we were in it and thought we had everything under control. We had our children tested several times while they were young, and everything seemed fine, though we were not told their exact levels. One thing I did not think about was our chickens.
We raise our own chickens – for the fun of it and to have healthier, more delicious eggs. I built our own coop, and it’s been a marvelous adventure. I recycled old doors from our garage, carefully scraping them on tarps in case there was any lead, and I thought that was enough. It turns out that they were still chipping, and when I looked it up online, there were accounts of other families who got lead exposure because their chickens pecked up lead specks from soil (UrbanMommas, 2009). I took my children for testing right away, and in the meantime, I scraped the doors again – repeatedly -- and repainted them. Particularly during the difficult three weeks waiting for results, I found myself with a terrible mix of guilt for not thinking about this – when I try so hard to consider all health risks to my children – and anger that the industry was allowed to carry on poisoning not only most children before 1978, but so many children still, and on into the future. It turns out that my children were below 5 µg/dL, but they weren't zero. And some children are not so lucky. When the planet is poisoned, children are also poisoned as a necessary consequence. We are still haunted by a burden imposed on us by generations in the recent past – our parents and grandparents. Let us be sure not to impose such burdens or worse ones onto the future – our own children and grandchildren.
Centers for Disease Control and Prevention (CDC). (2009). Fourth national report on human exposure to environmental chemicals: Executive summary. CDC. http://www.cdc.gov/exposurereport/pdf/FourthReport_ExecutiveSummary.pdf Accessed 18 July 2013.
Environmental Protection Agency (EPA). (2014). Learn about lead. EPA. Retrieved from http://www2.epa.gov/lead/learn-about-lead#lead
Grosse, S.D., Matte, T.D., Schwartz, J., Jackson, R.J. (2002). Economic gains resulting from the reduction in children’s exposure to lead in the United States. Environ Health Perspect 110 (6): 563-9.
Jones, R.L., Homa, D.M., Meyer, P.A., Brody, J.F., Caldwell, K.L., Pirkle, J.L., Brown, M.J. (2009). Trends in blood lead levels and blood lead testing among U.S. children aged 1 to 5 years, 1988-2004. Pediatrics 123 (3): e376-e385.
Kim, R., Hu, H., Rotnitzky, A., Bellinger, D., Needleman, H. (1995). A longitudinal study of chronic lead exposure and physical growth in Boston children. Environmental Health Perspectives 103 (10): 952-7.
Centers for Disease Control and Prevention (CDC). (2013). Blood lead levels in children aged 1-5 years – United State, 1999-2010. Morbidity and mortality weekly report (MMWR) 62 (13): 245-248.
Oreskes, N., Conway, E. (2011). Merchants of doubt: How a handful of scientists obscured the truth on issues from tobacco smoke to global warming. New York: Bloomsbury.
Plumlee, G.S., Durant, J.T., Morman, S.A., Neri, A., Wolf, R.E., Dooyema, C.A., Hageman, P.L. et al. (2013). Linking geological and health sciences to assess childhood lead poisoning from artisanal gold mining in Nigeria. Environmental Health Perspectives 121 (3): 744-750.
Schnur, J., John, R. M. (2014). Childhood lead poisoning and the new Centers for Disease Control and Prevention guidelines for lead exposure. J American Association Nurse Pract 25 (5): 238-247.
UrbanMommas. (2009). Backyard chickens, eggs, and lead. Urban Mommas: Word on the Street. Retrieved from http://www.urbanmamas.com/urbanmamas/2009/04/backyard-chickens-eggs-and-lead.html