10 Sep 2015: Opinion

Rachel Carson’s Critics Keep On,
But She Told Truth About DDT

More than half a century after scientist Rachel Carson warned of the dangers of overusing the pesticide DDT, conservative groups continue to vilify her and blame her for a resurgence of malaria. But DDT is still used in many countries where malaria now rages.

by richard conniff

Any time a writer mentions Rachel Carson’s 1962 book Silent Spring or the subsequent U.S. ban on DDT, the loonies come out of the woodwork. They blame Carson’s book for ending the use of DDT as a mosquito-killing pesticide. And because mosquitoes transmit malaria, that supposedly makes her culpable for just about every malaria death of the past half century.

The Competitive Enterprise Institute, a libertarian think tank, devotes an entire website to the notion that “Rachel was wrong,” asserting that
Rachel Carson
Biologist and author Rachel Carson in 1963.
“millions of people around the world suffer the painful and often deadly effects of malaria because one person sounded a false alarm.” Likewise former U.S. Senator Tom Coburn has declared that “millions of people, particularly children under five, died because governments bought into Carson’s junk science claims about DDT.” The novelist Michael Crichton even had one of his fictional characters assert that “Banning DDT killed more people than Hitler.” He put the death toll at 50 million.

It’s worth considering the many errors in this argument both because malaria remains an epidemic problem in much of the developing world and also because groups like the Competitive Enterprise Institute, backed by corporate interests, have latched onto DDT as a case study for undermining all environmental regulation.

The first thing worth remembering is that it wasn’t Rachel Carson who banned DDT. It was the very Republican Nixon Administration, in 1972. Moreover, the ban applied only in the United States, and even there it made an exception for public health uses. The ban was intended to prevent
Government agencies and pesticide manufacturers destroyed the effectiveness of DDT by promoting its overuse.
the imminent extinction of ospreys, peregrine falcons, and bald eagles, our national bird, among other species; they were vulnerable because DDT caused a fatal thinning of eggshells, which collapsed under the weight of the parent incubating them. But the ban did nothing to stop the manufacture or export of DDT. William Ruckelshaus, administrator of the Environmental Protection Agency, explicitly declared that his agency would not (indeed could not) “presume to regulate the felt necessities of other countries.”

So what actually happened with DDT? And why is malaria, which seemed to be en route to eradication in the 1950s, still killing 584,000 people a year? A team of public health researchers made a systematic review in 2012, in the Malaria Journal, of where and why resurgence of malaria has occurred in countries around the world. That study made no mention of Rachel Carson, focusing instead on the fickle nature of human commitment to public health.

In the 75 cases they examined, the researchers found that mosquito and malaria control programs failed 49 percent of the time for lack of funding. And the funding mostly stopped because of complacency and poor execution, or because of wars or disasters, or because of deliberate decisions to stop the program. In India, for instance, DDT helped reduce
spraying DDT in a home
Getty Images
DDT is still used in many countries. Here, a worker sprays DDT at a home in Bihar, India.
malaria incidence from 100 million cases to 100,000 cases by 1965. Then USAID handed off funding to the government of India, which failed to follow through adequately, causing malaria incidence to surge to six million cases in 1976.

“In several cases,” the researchers found, “donors appear to have reallocated funding specifically because successful reductions in malaria burden had occurred.” It was the same kind of complacency that’s common today among misinformed American parents who refuse to vaccinate their kids — and then watch children die from underrated diseases like measles or whooping cough. Even the World Health Organization (WHO) got it wrong, deciding in the late 1950s to cut funding and reduce staff for its anti-malaria program in Swaziland because malaria no longer seemed like much of a problem. Epidemics soon followed.

People also lost trust in DDT for a much more fundamental reason, though, as journalist Aaron Swartz put it, it’s “not one conservatives are particularly fond of: evolution.” Mosquitoes can produce multiple generations over the course of a year. Any pesticide will wipe out the vulnerable ones — and the ones that happen to be resistant because of some quirk in their biology or behavior rapidly take their place and proliferate. Thus DDT was already becoming ineffective in the early 1950s,
Babies in developing countries ingest accumulated DDT when they nurse at their mothers’ breasts.
so much so that in 1960, two years before Carson’s book, The New York Times headlined an article “Malaria Battle in Doubt; Warning Voiced That Carrier of Disease Could Outwit World's Scientific Skills.

If conservatives genuinely wanted to get at the reasons malaria eradication failed, they should be targeting the government agencies and pesticide manufacturers (among them Monsanto and Ciba, now part of BASF) who destroyed the effectiveness of DDT by promoting its massive overuse. Incredibly, the United States used 80 million pounds of DDT in 1959, much of it sprayed in a dense fog across forests and farm fields. All Rachel Carson did was to raise legitimate questions about the environmental and health dangers of this completely untested DDT abuse.

The war against malaria still goes on today, employing a rotation among a battery of different pesticides to hold off resistance. But all the current pesticides have problems of cost, effectiveness, or safety. Despite the assertion that Rachel Carson killed it off, DDT continues to be used in many countries, generally to spray on the interior walls of houses. (Even then, the protocol is to use DDT only after the mosquitoes have developed resistance to mosquito netting infused with pyrethroid pesticides, a more effective treatment.)

Despite the argument that Carson killed U.S. funding, our tax dollars still support this use of DDT through blanket grants that allow foreign nations to use any pesticide approved by the World Health Organization. But DDT is finally on the way out (a Chinese company is the only remaining manufacturer), and anti-malaria programs now live in the hope that an effective vaccine, a miracle drug, or new pesticides will consign the whole debate to history.

One final point: Carson’s critics like to assert that she exaggerated or even lied about the human health hazards of DDT. They argue, as a Crichton
Carson foresaw the hazards at a time when no one gave much thought to the consequences of our miracle products.
character declared, that it was “so safe you could eat it.” You will not, however, find Carson’s critics actually eating DDT to make their case. That’s apparently for people in the developing world, who ingest it when it flakes off their walls or ceilings. Babies ingest the accumulated load of DDT when they nurse at their mothers’ breasts. And yet studies increasingly link exposure to DDT to high blood pressure, Alzheimer’s disease, reproductive disorders, and a variety of other conditions, even two or three generations after exposure.

This increasingly leaves anti-malaria workers in the awkward position of “putting DDT in the mouths of babies through the mother’s milk,” said Graham White, a British specialist in tropical diseases and pesticides. They continue to rely on DDT because it may be the only way to prevent children from dying now. But they do so in the knowledge that it may seriously compromise their lives forever after.

Rachel Carson foresaw these hazards more than 50 years ago, at a time when no one else gave much thought to the environmental consequences of our miracle products, said Clive Shiff, a lifelong specialist in malaria and other tropical diseases at the Johns Hopkins Bloomberg School of Public Health. No one then thought much about bioaccumulation of chemicals, and no one imagined the idea of multigenerational epigenetic effects. Moreover, Shiff noted, she spoke out though all the powers of government, business, and science were lined up against her. “Rachel Carson was legitimately heroic,” he added. “You can say that loudly.”

The bottom line, sadly, is that Rachel was right.

POSTED ON 10 Sep 2015 IN Biodiversity Climate Policy & Politics Pollution & Health Science & Technology North America 


1300 lb mako shark caught in So Cal in 2013:

After running tests on its liver, scientists found DDT levels 100 times the legal limit for human consumption and PCB levels 250 times the legal limit, according to EPA standards.

Mercury levels in the shark’s muscles were higher than Department of Agriculture standards and would have prompted legal action to get the shark off store shelves. The levels were 45 times greater than the no-consumption limit for women of childbearing age and children. They were 15 times greater than limits for women over 45 and for men.

PCBs entered coastal Southern California through a number of means, as manufacturers dumped contaminated water in sewer systems.

DDT has a more limited origin. The chemical entered the waters off the Palos Verdes Peninsula from the late 1940s into the 1980s, when the Montrose Chemical Corp. was dumping DDT-laced water into the sewer system in Torrance. Los Angeles County sanitation districts discharged that water into the ocean off White Point on the Palos Verdes Peninsula.

From the late 1950s to the early 1970s, more than 1,700 tons of DDT entered the ocean from sanitation district pipes at a site designated as the Palos Verdes Shelf Superfund site in 1997. Estimates pegged the amount of DDT on the ocean floor there at 110 tons, but in 2013 officials revised that estimate to 14 tons. Officials didn’t know what had happened to the rest of the DDT.

Today, sharks and other marine creatures across coastal Southern California have DDT with a unique, trackable signature in their flesh.

“The high DDT tells us these animals are spending a lot of time feeding in Southern California,” Lowe said.

Posted by mauisurfer on 10 Sep 2015

The effectiveness of DDT is not a matter that insects become resistant. The real power of DDT is that it fights malaria through 3 mechanisms: repellency, irritability and lastly toxicity. So that even if the malaria mosquito develops resistance to toxicity it does not become immune to the repellency and irritability that DDT engenders which drive the mosquito away from the area sprayed with DDT. This spatial repellency factor of DDT has never stopped being effective as it protects people from the vector insect-borne diseases by reducing contact between disease-spreading insects and humans.

When looking at all the studies done on DDT there is still no real evidence that anyone has ever died or gotten cancer from DDT exposure. It is one of the safest pesticides ever discovered. What is obvious is that after DDT was banned all the other pesticides that came in to use after were toxic and caused numerous deaths and health problems. When parathion began to be used as a substitute there were reports of deaths among the farm workers spraying it. Also Dieldrin was originally developed in the 1940s as an alternative to DDT. It was very widely used during the 1950s to early 1970s. A study by the Journal of Clinical Epidemiology in the year 2000 indicates that Dieldrin is a estrogenic mimic shown to interact with the estrogen receptor. The study tracked 7712 women participants for 17 years and concluded that Dieldrin was associated with a significant increase in the risk of breast cancer. There’s also some other data available that shows that polychlorinated biphenyls, or PCBs are linked to higher risk of breast cancer. PCB’s were dumped into the environment from the 1930’s right up to 1979 and DDT became the scapegoat from numerous health problems in animals and humans caused by PCB’s.

A published report indicated that " Dr. Robert Golden of Environmental Risk Studies in Washington, DC, reviewed the research of numerous scientists and concluded that DDT and DDE (a breakdown product of DDT) have no significant estrogenic activity." On the other hand PCBs have been indicated to be estrogenic through binding to estrogen receptors. A lot of the claims against DDT were actually caused by these PCB's in the environment. It's only recently that this is coming to light with the discovery of Monsanto memos from 1969 showing that the agrochemical corporation Monsanto had been selling and using chemicals the company knew were harmful for the environment. The City of San Diego and the San Diego Unified Port District is suing Monsanto for " selling chemicals the multinational knew were harmful to the ecology, including that of the now heavily polluted San Diego Bay. "
Posted by DontDennyTruth on 11 Sep 2015

The belated attack on Rachel Carson is only one
of many similar attacks on science designed to
prevent government regulation of a wide range
of public health hazards in the United States.
That story is told in gruesome detail in The
Merchants of Doubt by Naomi Oreske and Erik
Conway, reviewed here:

Other examples of the same
strategy are tobacco (the first successful effort to
prevent government regulation for decades),
second-hand smoke, ozone depletion, acid rain,
and now climate change.

The companies which manufacturer products that
are harmful to the environment and public health
set up non-profit foundations such as the
Competitive Enterprise Institute to carry their
cover-stories for their products. Adding insult to
injury, their “donations” to these foundations are

The most important message in this article is that
evolution renders all pesticides useless very
quickly. There are now nearly 100 million acres
of glyphosate-resistant weeds in 36 states
because of the over use of glyphosate
(RoundUp). The medical establishment has
finally taken a position on the GMO seeds that
have enabled the poisoning of our food supply.
That story is told here:

Posted by Million Trees on 11 Sep 2015

What kind of an article is this? The author spends
time detailing that Carson was not to blame for
stopping the use of DDT and then concluding that
Carson was right in advocating the banning of DDT?
Posted by Rajendra LAKHOTIA on 12 Sep 2015

It turned out that women born before 1931, who were almost all past puberty when the spraying started, were no more likely to develop breast cancer than the control cases. That was generally consistent with the dozens of earlier studies. But women who had the highest exposure to DDT before the age of 14 were five times as likely to develop breast cancer later in life. All the other studies had missed this critical period.[7]

This was only the beginning. Cohn’s team has now completed a 54-year follow-up on daughters born to women in the Oakland study: daughters whose mothers had high levels of DDT while pregnant were more likely to develop breast cancer.[8] Another study found that boys whose pregnant mothers had high levels of DDT were also more likely to develop testicular cancer.[9] Ongoing research is investigating a range of other health impacts.

Posted by mauisurfer on 12 Sep 2015

NORAH G responds against false allegations regarding DDT and birds:

The public needs to be reminded that pest
control products do not routinely harm birds
during the course of their use. And
neither did DDT, which is no longer in use in
North America anyhow. Allegedly, DDT harmed
bird reproduction by thinning their egg-shells.
This seemingly led to the decline of the bald
eagle and the peregrine falcon. The effect of
DDT on bald eagles is a myth ! During the
sixteen-year period ( 1961 - 1977 ) representing
much of the end of the « DDT years », a mere
two hundred and sixty-six bald eagles were
found dead by the United States Fish And Wildlife
Service. As a matter of fact, early in the
twentieth century, hundreds of thousands of
these birds were destroyed, but not because of
DDT. A whopping one hundred and fifteen
thousand were calculatedly slaughtered by the
state of Alaska between 1917 and 1942.
Government-sponsored exterminations seem to
have killed more bald eagles than DDT allegedly
did. Everyone should maintain some perspective
on this matter. The allegations concerning DDT
are not true! It is a myth that the populations
of predatory birds have recovered remarkably
since the U.S. removal of DDT in 1972. It is also
a myth that birds like swallows have somehow
declined because of pest control products.
Overall urban encroachment is the far more likely
cause of bird decline. For more information about
DDT, go to The Pesticide Truths Web-Site ...

We are the National Organization Responding
Against HUJE that conspire to destroy the Green
space and other industries (NORAH G). As a
non-profit and independent organization, we are
environmentalists who are dedicated to reporting
about non-expert pesticide-hating fanatics, as well
as the work of respected and highly rated experts
who promote environmental realism and pesticide truths.
Get the latest details at: http://pesticidetruths.com/
— William H Gathercole and NORAH G


Yeah... Pesticides are harmless. DDT has been proven to be very harmful to humans and wildlife, especially to birds. DDT made their eggs thinner. There is plenty of scientific literature on this. People who have financial interest in selling pesticides and saying they are not harmful are totally unreliable. They simply lie.

Posted by DDT lover on 15 Sep 2015

During the 1950s and 1960s millions of acres of
New Brunswick and Maine forests were sprayed
with DDT to kill spruce budworms. One impact of
this spraying was massive mortality in young
salmon. This was well documented and I knew
(and still know) some of the researchers who
observed this. DDT was finally banned in Maine
in 1967, even though Rachel Carson described
the "rivers of death" in her book in 1962.
The logic that some uses of DDT might not be as
bad as some people suggested years ago,
therefore other uses must be acceptable or
other, documented impacts can be ignored, is
fallacious. Wide-scale spray programs, using
broad-spectrum pesticides, over complex
ecosystems are a very brutal, non-sustainable
approach, regardless of the pesticide used.
Posted by Mitch Lansky on 08 Jun 2016


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richard conniffABOUT THE AUTHOR
Richard Conniff is a National Magazine Award-winning writer whose articles have appeared in Time, Smithsonian, The Atlantic, National Geographic, and other publications. He is the author of several books, including The Species Seekers: Heroes, Fools, and the Mad Pursuit of Life on Earth. In previous articles for Yale Environment 360, he has reported on the role of electric power line corridors in conservation and a new crackdown on illegal fishing.



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