Rachel Carson's story is uniquely American: One person, at great personal risk, confronts powerful interests, and prevails. And in her case -- as in other enduring examples of this story -- the benefit extends beyond the individual and over time creates a better society for all of us.

Despite persistent and ad hominem attacks on Carson by the agriculture industry and the government for exposing the deadly effects of pesticides in her book "Silent Spring," Carson's meticulous attention to facts and levelheaded defense of those facts eventually led to the ban of DDT.

In 1962, the year "Silent Spring" was published, Carson, already a bestselling author, was 55 and beset by the breast cancer that would lead to her death two years later. As Minnesota author William Souder writes in his captivating biography, "On a Farther Shore," the woman at the center of this controversy over the United States' naive relationship with deadly chemicals was hardly strident or threatening.

"Rachel Carson had spent most of her adult life in the company of her mother -- writing, bird-watching, and visiting the seashore," Souder writes. "Petite, soft-spoken, and nearly apolitical, she lived quietly in a leafy suburb of Silver Spring, Maryland, with a cat and her orphaned ten-year-old grandnephew, Roger Christie, whom she had adopted."

So how did this private person, an information specialist in the Bureau of Fisheries, come to embody the environmental movement?

Souder writes about Carson's private life, including her modest upbringing, her educational influences, her writerly tussles with editors and her intense, (and probably) platonic relationship with Dorothy Freeman. He also places Carson firmly in the Cold War context of a rising industrialized and militarized nation that had achieved the unthinkable: the ability to alter the ecology of the earth through chemistry.

At the center of this change were two developments: our indiscriminate use of DDT and other pesticides, and the open-air testing of nuclear bombs in the South Pacific and American Southwest. "In the 1950s, their residues -- unseen and unbidden -- turned up everywhere, a feast of radionuclides and chlorinated hydrocarbons."

Carson was perhaps the first person to publicly connect the dots and alert the nation that both developments threatened not only the flora and fauna of the planet, but also our very existence. We were no longer separate from our environment. In fact, we never were and never would be.

Toward the end of her life, Souder recounts, Carson was featured on "CBS Reports," in which she answered her critics. "Now to these people apparently the balance of nature was something that was repealed as soon as man came on the scene. Well, you might just as well assume that you could repeal the laws of gravity. ... You can't just step in with some brute force and change one thing without changing many others. ... We must know the consequences."

Fifty years later, we are confronting those consequences.

Stephen J. Lyons is the author of three books, most recently "The 1,000-Year Flood." His writing appears in "Companions in Wonder: Children and Adults Exploring Nature Together."