Lead Wars. Gerald Markowitz
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Children suffered enormously as a result of this inaction. Until the 1950s, when BAL (British anti-Lewisite, or Dimercaprol) and CaEDTA (ethylenediaminetetraacetic acid) were introduced as chelating agents,41 two-thirds of children who suffered convulsions and swelling of the brain due to lead ingestion died. With the use of chelating agents, the death rate was cut in half, but it was still almost one in three,42 and those who did survive were often deeply damaged.
IT’S IN THE AIR: LEADED GASOLINE AND OTHER SOURCES OF LEAD DANGER
Increased attention to paint as a source of lead in the environment was complemented in the early and mid-1960s by a growing body of evidence suggesting that significant amounts of lead were also entering the human environment through other means: contamination of the soil and air from insecticides; and fallout from lead-bearing compounds during smelting, mining, and fabricating processes and automobile exhausts. Pots and pans, water pipes made of lead or joined by lead solders, and cans sealed with lead solder—once hailed by the industry as symbols of lead’s role in creating the modern environment—were now suspected as contaminants of the human food chain, as was beef, from the lead cattle absorbed in grazing. To explore these issues, the U.S. Public Health Service sponsored a conference in 1965 on environmental lead contamination, where it soon became clear that lead from gasoline was the most pressing concern because of its magnitude and dispersal throughout the country.
As early as the 1920s, public health leaders had worried that the introduction of lead into gasoline would, as the auto industry expanded, ultimately prove to be a serious source of environmental pollution.43 A 1966 study of lead in the soot of New York City streets, for example, revealed the startling fact that its lead concentration was 2,650 parts per million (ppm).44 Of particular worry at the time was the rapid expansion of the interstate highway system through the heart of most American cities: studies had found that much more lead was deposited from exhaust pipes when cars were moving at high speeds, thereby increasing the threat to urban populations.45
Yet since the 1920s the lead industry had sponsored research by Robert Kehoe that claimed that introducing more lead, even much more lead, into the environment presented no danger to people because, he argued, lead was a natural part of the human environment and people had developed mechanisms over the millennia to excrete lead as rapidly as they inhaled or ingested it. This rationale, that lead was a “natural” constituent of the human environment, became a mainstay of the industry argument from the 1920s forward. At the 1965 conference, Kehoe laid out the industry view of lead’s dangers: the intake of lead “is balanced for all practical purposes by an equivalent output,” so there was “an equilibrium with the environment.” Did the lead that people absorbed in the course of their daily lives constitute a risk? “The answer,” said Kehoe, “is in the negative.”46
This fanciful model of lead’s ecology was dismantled piece by piece as speaker after speaker at the conference, for the most part in a businesslike and respectful manner, questioned Kehoe’s underlying assumptions. While the world of lead toxicology was still relatively small and dominated by a few recognized experts, new voices, influenced by the emerging environmental movement following publication of Rachel Carson’s Silent Spring in 1962, were beginning to be heard. Criticisms of virtually every element of Kehoe’s model were made throughout the conference, but only on the last day did they coalesce as a full-blown rejection of the industry’s paradigm. Harry Heimann of Harvard’s School of Public Health, who had had experience working in the PHS Division of Air Pollution, told the conference that he wanted to make some “comments based on my listening for the last two days, having some discussions with some people in and outside the room, and my experience as a physician who has spent most of my life in public health work.” While he did not “mean to get into any acrimonious debate” and was “not intending to impugn anybody’s work,” Heimann confronted Kehoe directly. He announced that he felt compelled to “point out that there has been no evidence that has ever come to my attention . . . that a little lead is good for you.” It was, he went on, “extremely unusual in medical research that there is only one small group and one place in a country in which research in a specific area of knowledge is exclusively done.” Kehoe’s experiments that were said to provide evidence that lead from gasoline and other airborne sources presented little danger to people would need “to be repeated in many other places, and be extended,” before the scientific community lent them legitimacy. He also questioned Kehoe’s assertion that no danger existed below a blood lead level of 80 micrograms per deciliter, a reading that often corresponded with convulsions in adults working in lead-paint and other factories.47
In addition to presenting a clear challenge to the paradigm that Kehoe and the lead industry had carefully propagated for more than thirty years, participants at the 1965 conference challenged the very basis of industrial toxicology as it then existed. In the words of one attendee, lead toxicology put “the whole field of environmental health . . . on trial.”48 Scientists had for too long accepted the industry argument that if workers who were exposed to various toxins, including lead, did not show symptoms of disease, the public had little to worry about, since consumers were exposed to much lower levels of these materials. A broad public debate was needed on what was, and was not, an acceptable risk; industry assurances of safety were not sufficient. The “public at large [needed to] be given a rational basis on which to decide . . . that lead should or shouldn’t be taken out of gasoline, that pesticides should or shouldn’t be used in various situations, that asbestos should be curbed.”49 Indeed, in the coming years, the field of lead toxicology would be transformed to address just such concerns.
In the mid-1960s, Kehoe was just one of several industry supporters repeating the mantra that the critical measure of lead’s toxicity was the worker in the plant. Studies had shown that lead workers on average were absorbing less lead than earlier in the century, and industry touted this as proof that the public was protected as well. When Senator Edmund Muskie (D-ME) held hearings on air pollution in mid-1966, the LIA campaigned to undercut any criticism of the lead industry that might emerge. In addition to preparing articles and press releases to encourage “positive stories regarding lead and its uses,” the LIA developed testimony for the hearings.50 Felix Wormser, retired but still on retainer for St. Joseph Lead Company, testified on behalf of the LIA, asserting that “vast clinical evidence” showed that “the general public is not now, nor in the immediate future, facing a lead hazard.” Leaded gas posed no harm at all and a vast literature and much research confirmed this view, he claimed.51 Kehoe went on to testify that “the evidence at the present time is better than it has been at any time and that [lead] is not a present hazard.”52 His commitment to an 80 µg/dl blood-lead-level threshold blinded him to the possibility that, whatever this standard’s adequacy for protecting adults, children, because of lead’s effect on their developing neurological systems, might be at much greater risk at lower levels.
Though Kehoe’s position aroused skepticism among some in scientific and political arenas, it still found considerable acceptance among the general public. Kehoe himself had told Muskie’s committee that his laboratory was “the only source of new information” about lead in the factory and the environment and had “a wide influence in this country and abroad in shaping the point of view and activities . . . of those who are responsible for industrial and public hygiene.”53
Storm clouds were appearing on the horizon,