One moment a miracle drug or chemical is saving lives and eradicating longstanding killer diseases. Then come the side effects. Some are a litany of bodily risks a medical consumer must take to use the miracle… and others manifest themselves much, much later. Today’s blog is about one of most beneficial chemicals, one that countered yellow fever, malaria and many other mosquito-borne diseases… until its environmental bodily side effects were discovered. Its proper chemical name is dichlorodiphenyltrichloroethane; we know it simply as DDT, an insect killer that, when those side effects were clearly found, was banned in 1972.
According to the Encyclopedia Britannica, DDT’s “insecticidal properties were discovered in 1939 by a Swiss chemist, Paul Hermann Müller. During and after World War II, DDT was found to be effective against lice, fleas, and mosquitoes (the carriers of typhus, of plague, and of malaria and yellow fever, respectively) as well as the Colorado potato beetle, the spongy moth, and other insects that attack valuable crops. The chemical was widely used, though many species of insects rapidly developed resistant populations.
“As a result of repeated sprayings, DDT accumulated in soils in surprisingly large amounts … 10–100 pounds per acre. Its effects on wildlife greatly increased as it became associated with food chains. The stability of DDT led to its bioaccumulation in the bodily tissues of insects that constitute the diet of other animals higher up the food chain, with toxic effects on the latter. Songbirds and birds of prey, such as eagles, hawks, and falcons, were usually most severely affected, and serious declines in their populations have been traced to the effects of DDT. Use of DDT began to be restricted in the 1960s, thanks in part to the public awareness raised by Rachel Carson’s Silent Spring (1962). DDT was banned outright in the 1970s in many countries. The chemical is still used in some places, particularly as an indoor pesticide for mosquitoes in areas where malaria remains a major public health concern.”
One of the biggest issues of dealing with tons of stored DDT was what to do with it. So, in the 1970s, the United States determined that it should be disposed of… er… stored in large barrels and dumped into the ocean. For Southern California, that meant tossing those nasty barrels somewhere near Santa Catalina, right off the coast. The problem was that the barrels decomposed first, leaving high concentrations of intact DDT on the ocean floor… often in shallow layers on the floor’s surface. It seems that “the nation’s largest manufacturer of DDT had once used the ocean as a huge dumping ground — and that as many as half a million barrels of its acid waste had been poured straight into the water.
“Now, scientists have discovered that much of the DDT — which had been dumped largely in the 1940s and ’50s — never broke down. The chemical remains in its most potent form in startlingly high concentrations, spread across a wide swath of seafloor larger than the city of San Francisco… ‘We still see original DDT on the seafloor from 50, 60, 70 years ago, which tells us that it’s not breaking down the way that [we] once thought it should,’ said UC Santa Barbara scientist David Valentine, who shared these preliminary findings Thursday during a research update with more than 90 people working on the issue. ‘And what we’re seeing now is that there is DDT that has ended up all over the place, not just within this tight little circle on a map that we referred to as Dumpsite Two.’
“These revelations confirm some of the science community’s deepest concerns — and further complicate efforts to understand DDT’s toxic and insidious legacy in California. Public calls for action have intensified since The [LA] Times reported in 2020 that [DDT] is still haunting the marine environment today. Significant amounts of DDT-related compounds continue to accumulate in California condors and local dolphin populations, and a recent study linked the presence of this once-popular pesticide to an aggressive cancer in sea lions.
“With a $5.6-million research boost from Congress, at the urging of Sen. Dianne Feinstein (D-Calif.), numerous federal, state and local agencies have since joined with scientists and environmental nonprofits to figure out the extent of the contamination lurking 3,000 feet underwater. (An additional $5.2 million, overseen by California and USC Sea Grant, will be distributed this summer to kick off 18 more months of research.) The findings so far have been one stunning development after another. A preliminary sonar-mapping effort led by the Scripps Institution of Oceanography identified at least 70,000 debris-like objects on the seafloor.
“The U.S. Environmental Protection Agency, after combing through thousands of pages of old records, discovered that other toxic chemicals — as well as millions of tons of oil drilling waste — had also been dumped decades ago by other companies in more than a dozen areas off the Southern California coast.
“‘When the DDT was disposed, it is highly likely that other materials — either from the tanks on the barges, or barrels being pushed over the side of the barges — would have been disposed at the same time,’ said John Lyons, acting deputy director of the EPA’s Region 9 Superfund Division. He noted that the new science being shared this week is critical to answering one of the agency’s most burning questions: ‘Is the contamination moving? And is it moving in a way that threatens the marine environment or human health?’” Rosanna Xia writing for the March 24th Los Angeles Times. As we watch the continuous callous disregard of fully dealing with greenhouse gas emissions, climate change and its proven massive destructive power continue to get worse. We never seem to learn how bad our actions are until years later… Except with climate change, we know now. And still we let it continue with very limited efforts to stop what is becoming inevitable.
I’m Peter Dekom, and it does not make it “all right” to denigrate solid scientific fact, citing inconvenience or cost and substituting hope, mythology and religious guarantees instead, simply to deny what is happening right in front of us… every day.
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