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Curbing fallout and acid rain

Gorham led the way in curbing fallout, acid rain

Oct. 10, 2006

Two of the 20th century's most decisive and influential environmental discoveries came from one University professor: Eville Gorham, Regents Professor of Ecology. By finding how radioactive fallout entered the human food chain and uncovering the link between smokestack emissions and acid rain, he laid the basis for the first nuclear test ban treaty and curbs on industrial pollution. His story begins in the mid-1950s, when a common love of bloodhounds led Gorham, then a young researcher in England's Lake District, to become friends with a British medical officer named Frank Madge. Madge worried that an accident at a plutonium plant on the edge of the district could contaminate the water supply for several villages. In 1957 an accident did occur, releasing large amounts of radioactivity. Madge asked Gorham to test the local water for radioactivity. At first, Gorham found none. But when he tested local mosses and lichens, the radioactivity was nearly off the scale. "That's because mosses and lichens--lacking roots in the soil--derive their mineral supplies [for example, calcium and magnesium] mostly from rain and snow," Gorham explains. Thus, they pick up radioactivity in rain. Later, Gorham read that reindeer bones in Norway were rich in radioactivity compared to the bones of sheep. He reasoned that it was because reindeer, but not sheep, ate a lot of lichens, along with any radioactivity they had absorbed. He predicted that the Sami (Laplanders), who ate reindeer, would be contaminated and so would the Inuit, who consumed lichen-eating caribou. This turned out to be the case, and Gorham's work eventually figured in the test ban treaty of 1963. Similarly, when Gorham studied water chemistry of English bogs in 1955, he discovered that they picked up sulfuric acid whenever the winds blew in from industrial areas. So began a long series of papers on acid rain, including ones in which Gorham drew connections between acid rain and deaths from bronchitis and pneumonia. He also showed that gaseous sulfur dioxide from the smelters of Sudbury, Ont., was contaminating forests in that area. Later, Gorham served on a team that developed a plan for monitoring acid rain around the United States and provided the basis for the Carter administration's proposal to "scrub" industrial smokestacks. Today Gorham, who has been at the University since 1962 and is a member of the National Academy of Sciences, is chiefly concerned with the possible effects of global warming on the vast peatlands in northern areas. They store about 400 billion tons of carbon; if droughts and fires combine to ignite them, much of that carbon could be released as carbon dioxide and contribute significantly to global warming, he says. Of all the ecological problems he has encountered, Gorham finds global warming the toughest. "Everything in the planetary ecosystem depends on temperature, so it's far more pervasive than other problems," he says.

Further reading An extraordinary ecologist: Eville Gorham honored for lifetime achievement