Rachel Louise Carson was born in May 27, 1907. She is an American Marine biologist and conservationist. She wrote Silent Spring to advocate global environmental movement. Carson began her career as an aquatic biologist in the U.S. Bureau of Fisheries. Then she became a full-time nature writer in the 1950s. Carson wrote sea trilogy which explores the whole of ocean life from the shores to the depths. The trilogy includes The Sea around us, The Edge of the Sea and Under the Sea Wind.
Carson was interested in environmental problem caused by synthetic pesticides. Synthetic pesticides such as DDT (dicholordiphenyltricholorethane) was used in 1957 for fire ant eradication program and to treat Malaria and Typhus after World War I. Carson conducted research through National Institute of Health and U.S. Environment Protection Agency to write her book Silent Spring (1962).
Throughout her research, Carson found out that DDT is toxic to marine animals such as crayfish and sea shrimp. It is less toxic to mammals and moderately toxic to amphibians. DDE, DDT's metabolite has eggshell thinning effect, which lowers the reproductive rate. DDT is detrimental to human health as well. DDT is genotoxic, which has a deleterious action on a cell's genetic material. The metabolite (DDE) acts as an antiandrogen which has developmental and reproductive toxicity effect. According to WHO, it is moderately toxic to human. DDT is linked to diabetes and occupational exposure can cause neurological problems such as Parkinson's Disease and asthma. DDT also causes cancer of liver, pancreas, breast, leukemia lymphoma and testicular cancer.
After Silent Spring was published, Carson faced harsh criticism by chemical companies such as DuPont (a main manufacturer of DDT) and Velsicol Chemical company. Her book led to a nationwide ban on DDT and reversal in national pesticide policy. In 1972, there was an official restriction of the use of DDT, and DDT was replaced by less persistent alternative insecticides.
Carson was fighting against breast cancer at the time of controversy on DDT. On April 14, 1964 Carson died of respiratory virus, anemia, cancer spread to liver and of heart attack in her home Silver Spring, Maryland.
Carson's legacy still continues and the restriction on DDT is still controversial, because it is used to fight Malaria and developing countries need DDT (economic convenience).
