The Secret History of Lead
As more impartial studies were funded, however, the common-sense objections to leaded gas raised by public health campaigners in the twenties only seemed more prescient. Yandell Henderson, Alice Hamilton, David Edsall and numerous other eminent public health scholars had precisely predicted the problem sixty years earlier, before it became a global condition. Sadly, they were ignored. Dispersed into the air in automobile exhaust, lead dust would be no more healthy than it was when lead smelting was identified as a poisonous pastime 3,000 years ago. Moreover, as with many industrial toxins, the perceived acceptable level of exposure fell as further studies were finally carried out.
In the fifties and sixties, blood-lead levels of less than 60 micrograms (a microgram is a millionth of a gram) per deciliter (one-tenth of a liter) of blood (mcg/dl) were considered acceptable by America's medical establishment, not requiring intervention, because overt symptoms of lead poisoning, such as convulsions, do not typically occur below this level. Prior to that, dating back to the twenties, lead poisoning usually had to be severe enough to cause death or severe brain damage to be considered a diagnosed poisoning event. A corresponding blood-lead level of 80-100 mcg/dl or possibly higher might be imputed. In the intervening years, the acceptable level has dropped steadily from 40 mcg/dl to 30 to 25 and now to 10 or below.
Though the lead industry advocacy groups cling to the old numbers, the CDC, the American Academy of Pediatrics, the EPA and the National Academy of Sciences have agreed that the ill-health effects beginning at 10 mcg/dl are established fact, "an unprecedented coherence of opinion in the field of neurotoxicology." In 1994 a letter to the editors of the medical journal Pediatrics, several prominent lead research doctors addressing industry naysayers wrote, "If this massive database is not persuasive for lead, then no other chemical can be considered to have been demonstrated to be toxic."
Completing a sequence familiar to pollution watchers, a recent review of scientific research by the National Research Council has led it to conclude, "There is growing evidence that there is no effective threshold for some of the adverse effects of lead." Children are especially at risk. Summarizing its study of the relevant science, the Department of Housing and Urban Development wrote, "There does not yet appear to be a discernible threshold for the adverse effects of lead on the young."
In a 90,000-word 1997 review of all scientific evidence on the subject, Erik Millstone of the Science and Technology Policy Research Unit at Sussex University concluded that children suffer ill effects from lead at especially low exposures--much lower than was thought even recently--including reduced IQ, behavioral and learning difficulties and hyperactivity. Children are 4-5 times more susceptible to the effects of lead than adults. According to the CDC this is because children's digestive systems absorb more lead than adults--40-50 percent of that ingested versus 10-15 percent. In addition to breathing it in, children will ingest large quantities of airborne lead when it settles on soil, dust, food and playthings, which eventually contact their mouths. Based on research linking the two, in 1998 the Justice Department began studying the impact of childhood lead exposure on juvenile delinquent behavior.
Perhaps the only encouraging news in any discussion of leaded gasoline is how readily blood-lead levels fall when its use is trimmed or eliminated. The US phaseout of lead began in 1975 and was largely complete by 1986. Based on data collected in more than sixty US cities by the CDC, the Department of Health and Human Services reported that blood-lead levels in Americans aged 1-74 had declined 78 percent between 1978 and 1991.
For children aged 1-5, blood-lead levels decreased 76 percent, from 15.0 to 3.6 mcg/dl. The percent of children with blood-lead levels greater than or equal to 10 micrograms declined from 88 percent to 9 percent. The British Medical Journal reported three years ago that since Britain's lead phaseout began, blood-lead levels there had fallen by two-thirds. In New York City, where the war against tetraethyl lead can be said to have first begun with its ban in 1925, Dr. Sergio Piomelli, a hematologist at Columbia University's Children's Hospital, has reported that before the US lead phaseout began, 30,000 out of 100,000 New York City children tested had elevated lead levels; after the phaseout was complete, 1,500 of 100,000 had similarly high levels. In 2000, he told The Nation, the affected population is even smaller.
Still, one of the most telling measures of the extent of human lead contamination--careful measurement of lead levels in the bones of our preindustrial ancestors--argues against too much backslapping. A 1992 article in The New England Journal of Medicine revealed that pre-Columbian inhabitants of North America had average blood-lead levels 625 times lower than the current "safe" level of 10 mcg/dl.
Foreign custom kept Ethyl in business, and it put Octel on the map. In the seventies, with the auto industry embracing catalytic converters and talk of a lead phaseout circulating, the US market seemed certain to shrink, making foreign profits increasingly important to the lead giants. Casting back over 1972 in its annual report for that year, Ethyl reminded shareholders, "Continued penetration of expanding world markets would lessen any...impact on Ethyl's total antiknock sales." The following year, noting growing reservations about the American market, it went on to recall: "Sales of antiknock compounds continued to increase in all overseas markets in 1973. To promote this growth, Ethyl International added antiknock bulk terminals in the Far East, Middle East and South America. Construction of other terminals in various areas of the world is planned in 1974 and 1975."
Ethyl further elaborated its foreign strategy in 1974: "Most foreign countries have recognized the importance of the role lead antiknocks play in conserving crude oil in this period of shortages.... we believe antiknocks will continue to constitute a major product of the Company for years to come whether or not there is a domestic reduction in use of lead in gasoline."
By 1979 the company would observe, "It is worth noting that during the second half of 1979, for the first time, Ethyl's foreign sales of lead antiknock compounds exceeded domestic sales." Ethyl and Octel both were additionally fortunate in being able to manipulate their prices to keep profit levels high. As Octel reported in a 1998 SEC filing, "From 1989 to 1995, the Company was able to substantially offset the financial effects of the declining demand for TEL through higher TEL pricing. The magnitude of these price increases reflected the cost effectiveness of TEL as an octane enhancer as well as the high cost of converting refineries to produce higher octane grades of fuel." In other words, they had their customers over a barrel.