By late 1957, Carson was focused on the issue of pesticide spraying. She gathered evidence of the harmful effects of such chemicals on the environment to write a book and wrote letters speaking out against the plan. From 1958 to 1962, Carson wrote the Silent Spring to speak out against widespread use of pesticide spraying and its toxic chemical ingredients. Its publication was delayed due to Carson’s ailing health and her battle with cancer, and was strongly opposed by the chemical industry. The book was finally published in 1962.