of adding tetraethyl lead to gasoline. Hamilton also remained an activist in social reform efforts. Her specific interests in civil liberties, peace, birth control, and protective labor legislation for women caused some of her critics to consider her a "radical" and a "subversive." From 1924 to 1930, she served as the only woman member of the League of Nations Health Committee. She also visited the Soviet Union in 1924 and Nazi Germany in April 1933. Hamilton wrote "The Youth Who Are Hitler's Strength," which was published in The New York Times. The article described Nazi exploitation of youth in the years between the two world wars. She also criticized the Nazi education, especially its domestic training for girls. Later years After her retirement from Harvard in 1935, Hamilton became a medical consultant to the U.S. Division of Labor Standards. Her last field survey, which was made in 1937–38, investigated the viscose rayon industry. In addition, Hamilton served as president of the National Consumers League from 1944 to 1949. Hamilton spent her retirement years in Hadlyme, Connecticut, at the home she had purchased in 1916 with her sister, Margaret. Hamilton remained an active writer in retirement. Her autobiography, Exploring the Dangerous Trades, was published in 1943. Hamilton and coauthor Harriet Louise Hardy also revised Industrial Toxicology (1949), the textbook that Hamilton had initially written in 1934. Hamilton also enjoyed leisure activities such as reading, sketching, and writing, as well as spending time among her family and friends. Death and legacy Hamilton died of a stroke at her home in Hadlyme, Connecticut, on September 22, 1970, at the age of 101. She is buried at Cove Cemetery in Hadlyme. Hamilton was a tireless researcher and crusader against the use of toxic substances in the workplace. Within three months of her death in 1970, the U.S. Congress passed the Occupational Safety and Health Act to improve workplace safety in the United States. Recognition and awards Hamilton was awarded honorary degrees from the University of Michigan, Mount Holyoke College, and Smith College. She was included in the American Men in Science: A Biographical Dictionary (1906). In 1935 Eleanor Roosevelt presented Hamilton with the Chi Omega women's fraternity's National Achievement Award. In 1947 Hamilton became the first woman to receive the Albert Lasker Public Service Award for her public service contributions. In 1948 Hamilton received the Donald E. Cummings Memorial Awards from the American Industrial