How one scientist took on the chemical industry - Mark Lytle

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In 1958, after receiving a letter describing the deaths of songbirds due to the pesticide known as DDT, Rachel Carson began an investigation into the misuse of chemicals and their toll on nature. In 1962, she published her findings in “Silent Spring,” which immediately drew both applause and impassioned dissent. How did this biologist and writer ignite such controversy? Mark Lytle investigates.

Lesson by Mark Lytle, directed by Héloïse Dorsan Rachet.

In 1958, Rachel Carson received a letter

describing songbirds suddenly dropping
from tree branches.

The writer blamed their deaths
on a pesticide called DDT

that exterminators had sprayed
on a nearby marsh.

The letter was the push
Carson needed to investigate DDT.

She had already heard from scientists
and conservationists who were worried

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

and possibly humans.

She began to make inquiries
through government contacts

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

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

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

Her book documented
the misuse of chemicals

and their toll on nature
and human health.

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

along with vicious personal attacks
on the author.

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

Carson began her career
as a hardworking graduate student,

balancing her studies in biology
at John Hopkins University

with part time jobs.

Still, she had to leave school
before completing her doctorate

to provide for her ailing father
and sister.

Carson found part time work
with the Bureau of Fisheries

writing for a radio program
on marine biology.

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

impressed her superiors,
and in 1936,

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

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

combining science with lyrical meditations
on underwater worlds.

These explorations resonated
with a wide audience.

In "Silent Spring,"
Carson turned her attention

to the ways human actions
threaten the balance of nature.

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

and protect soldiers
from insect-borne diseases.

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

often with unforeseen results.

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

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

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

and chemical companies
extolled the benefits of DDT.

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

But Carson showed how
the overuse of chemicals

led to the evolution
of resistant species—

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

Since DDT does not dissolve in water,

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

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

and eventually humans.

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

with unknown consequences
for future generations.

The response to "Silent Spring"
was explosive.

For many people the book
was a call to regulate substances

capable of catastrophic harm.

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

controlling the threat insects
posed to human health.

Former Secretary of Agriculture
Ezra Taft Benson demanded to know

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

and dismissed Carson
as “probably a Communist.”

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

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

In reality, Carson had focused
on the dangers of chemicals

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

She rejected the prevailing belief
that humans

should and could control nature.

Instead, she challenged people
to cultivate

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

Carson died of cancer in 1964,

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

Her work galvanized a generation
of environmental activists.

In 1969, under pressure
from environmentalists,

Congress passed
the National Environmental Policy Act

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

To enforce the act,

President Richard Nixon created
the Environmental Protection Agency.

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

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

through the lingering impact
of her writing.