Clio's Current has wandered widely in its foray into online history, but there are some topics which we have avoided. Some because we know nothing about them, and others because we know just enough that we know we have nothing worth saying. Environmental and medical history fall into the second category. In a two part series, we touch on these unfamiliar fields while exploring the history of lead use in North America.
Lead is a well-known danger to North American families. Lead in toys causes recalls, while lead paint in old houses causes both literal and figurative headaches. Humans have been using lead for centuries since it's easily melted down or moulded into other forms. We can trace its use as far back as the Bronze Age. Its production first peaked at the height of Roman Empire, where it was used for piping and architecture. Lead production expanded again as industrial societies expanded in the 19th century. By the early 20th century, doctors were familiar with the negative impact of lead on humans, but it still continued to be used.
In the 1920s, General Motors discovered that the gasoline they were using to run automobile engines could be made more powerful. By adding tetraethyl lead they could increase the ignition point of gasoline and improved the thermal efficiency of engines. Without going into the details of how a combustion engine works, better thermal efficiency meant that engines could produce more power for a given size. So a smaller engine running on leaded gasoline could run faster and more efficiently using less fuel than a larger one using unleaded gasoline. Besides allowing cars to go faster and farther, the newly invented airplane especially required more power for less fuel, since any extra weight drastically impacted the distance which they could travel. General Motors began producing leaded gasoline and soon noticed their workers were getting sick. They simultaneously ignored the issue and through their subsidiary Ethyl Corporation, reassured consumers that “our continued development of motor fuels is essential in our civilization” and called lead “a gift of God.”
As more workers became ill and evidence against the use of leaded gasoline grew, the US Treasury Department moved to review its use in 1925. Unfortunately, corporations successfully argued that lead would not cause too much harm on the American population and that its utility superseded the potential risk. Incredibly, one health advocate warned that with the decision to continue using leaded gasoline, “conditions would grow worse so gradually and the development of lead poisoning will come so insidiously . . . that leaded gasoline will have been old . . . before the public and the government awaken to the situation." These ominous words were regrettably prescient.
For the next four decades, lead poisoning increased throughout the United States as a “silent epidemic.” The Second World War saw a 70% rise in the use of lead, as the war caused a drastic increase in the production of leaded gasoline, lead bullets, and using lead in ships and motors to prevent corrosion. Wartime shortages of other metals also meant lead was used as a substitute. Christian Warren has written about the “social history of lead poisoning” and she introduces her book with the telling phrase, “the United States is lead poisoned.” She goes on to explain that even as lead use increased, the medical definition of unsafe amounts of lead in blood decreased. Thus, “lead poisoning” became more prevalent as doctors lowered the amount of lead blood levels necessary to be considered “poisoned.”
Warren also examines how attention to the lead problem only gained national attention in the United Stated in 1969 when Jack Newfield first published an article in New York City's Village Voice. His article was appropriately titled, “Silent Epidemic in the Slums,” highlighting an important reason why lead poisoning had been so unnoticed for so long. Children suffering from lead poisoning were most often from the poor or at least “non-white,” which in mid-20th century America meant that few politicians cared about their concerns. They were the ones buying cheaper houses and toys where lead had been used. Like Warren, David and Andrew Bellinger trace the political movement against lead poisoning and argue that its roots lay with “the civil rights and the environmental movements [that] combined to create concern about environmental justice, based on the observation that poor people were disproportionately affected by environmental hazards.” The eventual banning of lead in gasoline and other products was a triumph for environmentalists as well as civil rights and poverty activists.
Today lead in products is regulated and controlled. Blood lead levels have declined by more than 70% in Canada since the late 1970s. Today Canadian gasoline is 99.8% lead-free, with a few exemptions remaining for high octane fuel. Having been born in the 80s, the authors of this blog have had (hopefully) little contact with lead. As a public health issue, it is effectively eliminated in the Western world, though in 2010 Nigeria suffered one of the worst cases of lead poisoning in recent memory. There, gold mining led to villages becoming contaminated, and despite the prosperous industry, efforts to clean up have been impeded by lack of funds since none are available to local sources.
As the Bellingers' article notes, the history of lead poisoning is a revealing example of how scientific knowledge interacts with public health policy. Notably in the case of lead poisoning, science failed to sway the government to intervene and instead economic benefits guided policy. The consequences were as embarrassing as they were tragic, since it was so obvious that lead caused serious medical harm. Some have even claimed that the lead poisoning epidemic explains the rise in violent crime in the 1970s and its decline in the 1990s. While a poster in our favourite subreddit, /r/AskHistorians, thoroughly debunked such a wide-ranging explanation for a complex issue like violent crime, it's clear that the pervasiveness of lead use had a terrible impact on industrial society for decades, if not centuries.
The history of lead usage easily crosses both environmental and medical histories and offers vital lessons for us today. The history of contaminants that are knowingly (or worse, unknowingly) injected into our “ecosystem” is a dire one, but one which has many important lessons about the consequences of inaction. How many children and adult lives were changed from the insistence that lead was “safe enough”? The history of lead poisoning is a revealing example of why the state's public health policy must be guided by scientific evidence, not solely economic concerns. At the same time, doctors' changing definition of what was considered “lead poisoning” reminds us that the medical profession is far from infallible. There must be room for new medical knowledge and practices to shape public health policy.
Next post, we are going to try to take some of the lessons we've garnered from this subject and try to understand how we can apply them to the present in a meaningful way.