A leading expert in the field of occupational health and a pioneer in the field of toxicology, Hamilton was dedicated to uncovering and identifying industrial toxins. She was known for her courage in studying occupational illnesses and the dangerous effects of industrial metals and chemical compounds on the human body. Often, she could be found exploring the more dangerous parts of the urban workplaces of America, delving into mines, and working her way into factories reluctant to admit her.

She published numerous benchmark studies that helped raise awareness of dangers in the workplace. In 1919 she became the first woman appointed to the faculty at Harvard Medical School, serving in their new Department of Industrial Medicine.

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I chose medicine not because I was scientifically-minded, for I was deeply ignorant of science. I chose it because as a doctor I could go anywhere I pleased — to far-off lands or to city slums — and be quite sure I could be of use anywhere.

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Alice Hamilton
Exploring the Dangerous Trades: The Autobiography of Alice Hamilton (1943)