Robert A. Kehoe

Robert A. Kehoe (November 18, 1893 – November 24, 1992) was an American toxicologist and leader in occupational health. Kehoe was the foremost medical apologist for the use of tetraethyllead as an additive in gasoline.

Family and education

Kehoe was born in Georgetown, Ohio, on November 18, 1893 to Jeremiah and Jessie Kehoe.

Robert studied at Ohio State University. After his graduation at the University of Cincinnati (UC) medical school in 1920 he was a resident in pathology at the Cincinnati General Hospital.

Shortly after obtaining his M.D. he married Lucille Marshall.

Occupational health

When he was an instructor in the UC Department of Physiology in 1924, he was hired by Charles Kettering for General Motors (GM) to examine health issues related to the production of tetraethyllead (TEL). In 1925 Kehoe became the chief medical advisor of the Ethyl Corporation, a position he held until his retirement.

In 1930, he became the director of the newly created UC Kettering Laboratory of Applied Physiology, the first university-based laboratory devoted to toxicological problems peculiar to industry. The laboratory was funded by the stakeholder industry, GM, DuPont, and Ethyl Corporation.

At the Kettering Laboratory, Kehoe was commissioned by DuPont to produce a study to show that the carcinogen 2-Naphthylamine, then widely used by DuPont and shown to produce cancer in nine out of ten employees exposed to it, was safe. Kehoe was named Professor of Industrial Medicine at UC and put together an interdisciplinary team to investigate occupational health issues.

Advocacy of lead in gasoline

Working at the GM Research Laboratory at Dayton, Ohio, Thomas Midgley and Charles Kettering studied anti-knocking agents. In 1921, they discovered TEL's anti-knocking property and proceeded to patent its use in gasoline, allowing engines to work with higher compression. Two years later, GM and Standard Oil established the Ethyl Corporation to produce TEL as a gasoline additive with the help of DuPont. Soon, workers at Ethyl plants fell ill and a number of them died from lead poisoning. Kettering hired Kehoe to develop protocols for the workers handling TEL. Kehoe soon became the main medical advocate for the position that the use of TEL in gasoline is safe and gained prominence as the industry's expert at government and public health hearings. As almost all research support concerning leaded gasoline support came from industry and most was channeled to him, he held "an almost complete monopoly" on data for half a century. Kehoe believed that presence of lead in humans and other organisms was normal and that exposure to low lead levels was not harmful.

In a 1966 government hearing chaired by Senator Edmund Muskie, Kehoe stated that his laboratory "was the only source of new information (about lead exposure)" and "had wide influence (in the US and abroad) in shaping the point of view and activities... of those who are responsible for industrial and public hygiene".

Although lead had been known to be highly toxic since antiquity, Kehoe’s beliefs were not rejected by most people until after Clair Cameron Patterson’s publication in 1965. It became clear that global lead contamination was taking place and that it had started gradually with the Industrial Revolution but had been markedly accelerated once leaded gasoline had entered the market. While leaded gasoline had been quickly accepted as "safe" in the 1920s, it took decades since Patterson's discovery to act upon the findings of its toxicity. By 2014, a majority of countries had discontinued the use of leaded gasoline, yet leaded gasoline continues to be produced and used in some markets.

Kehoe Paradigm

Kehoe was the medical spokesman for Ethyl Corporation and other industries who profited from the production of leaded gasoline. When early on Alice Hamilton, Yandell Henderson and other scientists raised doubts about its safety and workers at TEL plants fell ill, the Surgeon General, Hugh Smith Cumming called for a conference in 1925. TEL production was voluntarily suspended, but the use of leaded gasoline raised public health issues that were novel. At the conference Kehoe challenged his opponents for proof that use of TEL was unsafe. His Show me the data paradigm shifted the burden of proof to the doubters. The alternative approach, the precautionary principle, would have required proof that TEL was safe before it could be used. While the Kehoe Paradigm (or Kehoe Rule) assumes that in the absence of clear evidence of risk, there is no risk of significance, the precautionary principle assumes that there is a possible risk until it is proved otherwise. Nriagu indicated that with the large investments by industry, the social and economic climate of the time, and the belief in progress, the outcome of the 1925 conference was preordained. TEL production resumed, and soon, leaded gasoline was commonly used. That there were alternatives to the use of TEL was falsely denied by the industry.

The Show me the data approach made it critical for the industry to fund and control the research in lead toxicity. That was done through the Kettering Laboratory, under Kehoe’s direction. The Kehoe Paradigm worked for the lead industry, as all that was necessary now was to characterize any criticism as fraught with uncertainty. In the case of lead toxicity, Kehoe's laboratory dominated the scene for decades, attesting to the safety of leaded gasoline and deconstructing any criticism. The credibility of his research was bolstered for decades by the support of the US Public Health Service and American Medical Association.

Using Kehoe's paradigm, Ethyl Corporation was a winner in either situation: if its product would prove to be safe, it would be seen as a responsible party. If, however, its product was unsafe, it would take decades to prove this with certainty in a process that could be prolonged by challenging the methods and results and calling for more data. Meanwhile, production was profitable, and ultimately, the owners would be insulated from responsibility. Kitman indicates that the strategy taken by the lead industry, namely the use of Kehoe's Paradigm, "provided a model for the asbestos, tobacco, pesticide and nuclear power industries, and other(s)... for evading clear evidence that their products are harmful by hiding behind the mantle of scientific uncertainty." Kettering Laboratories under Kehoe's leadership also certified the safety of the fluorinated refrigerant, Freon, "another environmentally insensitive GM patent that would earn hundreds of millions before it was outlawed."

Death

Kehoe retired in 1965. He died in Cincinnati in 1992 at the age of 99.