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In 1958, Rachel Carson received a letter

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describing songbirds suddenly dropping 
from tree branches.

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The writer blamed their deaths 
on a pesticide called DDT

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that exterminators had sprayed 
on a nearby marsh.

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The letter was the push 
Carson needed to investigate DDT.

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She had already heard from scientists 
and conservationists who were worried

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that rampant use of the pesticide 
posed a threat to fish, birds,

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and possibly humans.

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She began to make inquiries 
through government contacts

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from her years working 
in the United States Bureau of Fisheries.

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She asked: “what has already silenced 
the voices of spring?”

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In 1962, Carson published her findings 
in "Silent Spring."

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Her book documented 
the misuse of chemicals

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and their toll on nature 
and human health.

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"Silent Spring" immediately drew both 
applause and impassioned dissent—

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along with vicious personal attacks 
on the author.

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How did this mild-mannered biologist 
and writer ignite such controversy?

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Carson began her career 
as a hardworking graduate student,

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balancing her studies in biology 
at John Hopkins University

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with part time jobs.

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Still, she had to leave school 
before completing her doctorate

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to provide for her ailing father 
and sister.

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Carson found part time work 
with the Bureau of Fisheries

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writing for a radio program 
on marine biology.

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Her ability to write materials that could 
hold the general public’s attention

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impressed her superiors, 
and in 1936,

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she became the second woman 
to be hired at the Bureau full time.

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In 1941, she published 
the first of three books on the ocean,

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combining science with lyrical meditations
on underwater worlds.

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These explorations resonated 
with a wide audience.

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In "Silent Spring," 
Carson turned her attention

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to the ways human actions 
threaten the balance of nature.

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DDT was originally used during 
World War II to shield crops from insects

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and protect soldiers 
from insect-borne diseases.

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After the war, it was routinely sprayed 
in wide swaths to fight pests,

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often with unforeseen results.

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One attempt to eradicate fire ants 
in the southern U.S.

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killed wildlife indiscriminately,
but did little to eliminate the ants.

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In spite of this and other mishaps, 
the US Department of Agriculture

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and chemical companies 
extolled the benefits of DDT.

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There was little regulation or public 
awareness about its potential harm.

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But Carson showed how 
the overuse of chemicals

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led to the evolution 
of resistant species—

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which, in turn, encouraged the development
of deadlier chemicals.

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Since DDT does not dissolve in water,

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she asserted that over time 
it would accumulate in the environment,

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the bodies of insects, the tissues 
of animals who consume those insects,

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and eventually humans.

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She suggested that exposure to DDT 
might alter the structure of genes,

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with unknown consequences 
for future generations.

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The response to "Silent Spring" 
was explosive.

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For many people the book 
was a call to regulate substances

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capable of catastrophic harm.

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Others objected that Carson 
hadn’t mentioned DDT’s role

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controlling the threat insects 
posed to human health.

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Former Secretary of Agriculture 
Ezra Taft Benson demanded to know

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“why a spinster with no children 
was so concerned about genetics?”

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and dismissed Carson 
as “probably a Communist.”

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A lawyer for a pesticide manufacturer 
alluded to Carson and her supporters

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as “sinister influences” 
aiming to paint businesses as “immoral.”

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In reality, Carson had focused 
on the dangers of chemicals

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because they weren’t widely understood, 
while the merits were well publicized.

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She rejected the prevailing belief 
that humans

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should and could control nature.

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Instead, she challenged people 
to cultivate

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“maturity and mastery, not of nature, 
but of ourselves.”

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Carson died of cancer in 1964,

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only two years after 
the publication of "Silent Spring."

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Her work galvanized a generation 
of environmental activists.

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In 1969, under pressure 
from environmentalists,

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Congress passed 
the National Environmental Policy Act

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that required federal agencies to evaluate
environmental impacts of their actions.

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To enforce the act,

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President Richard Nixon created 
the Environmental Protection Agency.

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And in 1972, the EPA issued 
a partial ban on the use of DDT.

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Long after her death, Rachel Carson 
continued to advocate for nature

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through the lingering impact 
of her writing.