From the biography of "Boss Kettering", first president of Ethyl Corporation, makers of tetra ethyl lead (TEL), comes this cautionary tale*

After working with TEL for twelve months, Ethyl's vice-president, Thomas Midgley, the man responsible for the discovery of the anti-knock properties of tetra ethyl lead, asked his boss, Kettering, for leave in order to throw off his organic lead poisoning. Eighteen months later, in mid-I924, two men had died and sixty others had been seriously affected by lead poisoning in the Ohio blending plant.

Kettering needed medical research which would prove TEL was safe to manufacture and to use, in order to effectively market the new leaded gasoline nationally. Only weeks after the required research was published, an accident in the New Jersey TEL blending plant killed ten men and sent fifty more to hospital, many in straightjackets to control their delirium. New York City quickly banned the manufacture, sale and use of leaded gasoline and soon after, Ethyl suspended production and marketing of leaded fuel in most areas.

Kettering was angered by the government interference and public hysteria. Despite a dozen men dead, he managed to convince the Surgeon General that the economic and military benefits of TEL far outweighed the unsubstantiated health risks.

Accordingly, and in contradiction of the Precautionary Principle, the burden of proof was placed on those who were concerned about the effects of scattering large amounts of fine lead powder over a long period of time from exhaust emissions.

Production started up again in 1926 and the proof for the risks to public health came nearly forty years later.

* James McCredie kindly supplied the reference for this extract, 'Boss Kettering' - Wizard of General Motors by Stuart W. Leslie, Columbia University Press, New York,1983.