The mass murdress Rachel Carson’s book prompted hysteria amongst so-called environmentalists who assigned the cause of blame of a higher incidence of leukemia and liver tumors in mice fed DDT than in unexposed mice the decline in populations of such wild bird species as the ospreys and peregrine falcons on the contamination by DDT of their environment.
Actual epidemiological studies, however, found no increases in liver cancer in populations where DDT was in constant use – the WHO investigated the 1969 mice study, and found that /i>both</i> cases and controls had developed a surprising number of tumors. It turned out that foods fed to both groups were mouldy and contained aflatoxin, a carcinogen. (When the tests were repeated using non-contaminated foods, neither group developed tumours.)
As far as the ‘death of birds’ BS goes, declines in bird populations were documented as occurring either before DDT was present or years after DDT’s use. The Audubon Society’s Christmas Bird Counts between 1941 (pre-DDT) and 1960 show that at least 26 different kinds of birds became <i>more</i> numerous during
the period of greatest DDT usage, including an overall increase in the numbers of birds seen per observer from 1941 to 1960, (Bald eagles, the talisman species – 197 bald eagles documented in 1941,
891 in 1960.
Similar studies in Canada and the UK provided similar results. In Canadian peregrines “reproducing normally” in the 1960s even though their tissues contained 30 times more DDT than did
the tissues of the peregrines in the alarmist studies in the US Mid West. In the UK, the results of a three-year study published in 1969, noted that the decline of peregrine falcons in Britain
had ended in 1966 even though DDT levels were as
abundant as ever. The study concluded that “There is no close correlation between the decline in population of predatory birds, particularly the peregrine falcon and the sparrow hawk, and the use of DDT.”
The Ban.
In 1971, in the US, authority over pesticides was transferred from the DoA to th newly EPA. In April 1972, after seven months of testimony, Federal Judge Edmund Sweeney stated that in his judgement that “DDT is not a carcinogenic hazard to man . . . The uses of DDT under the regulations involved here do not have a deleterious effect on freshwater fish, estuarine organisms, wildbirds, or other wildlife . . . The evidence in this proceeding supports the conclusion that there is a present need for the essential uses of DDT.” Two months later EPA head William Ruckelshaus—<i>who had never attended a single day’s session in theseven months of EPA hearings, and <b>who admitted hehad not even read the transcript of the hearings</b>—</i> declared that DDT was a “potential human carcinogen” and banned it for virtually all uses.The effects.
Amongst others: In Sri Lanka DDT spraying had reduced malaria cases from 2.8 million in 1948 to <b>17</b> in 1963. After spraying was stopped in 1964, malaria cases began to rise again and reached
2.5 million in 1969.
In Zanzibar, the prevalence of malaria among the populace dropped from 70 percent in 1958, when DDT spraying became widespread, to 5 percent in 1964, when DDT spraying stopped. By 1984 it was back up to between 50 and 60 percent.
There’s lots more…
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