Here is another example that demonstrates the tightly linked interests that both cause and treat cancer. In 1978, Imperial Chemical Industries (ICI), one of the largest companies in the world, specializing in agrochemicals and pharmaceuticals, developed the cancer drug tamoxifen. In 1985, along with the American Cancer Society, ICI founded the National Breast Cancer Awareness Month with the aim of promoting mammography as the most effective tool against breast cancer. In 1990 Imperial Chemical Industries was accused of dumping DDT and PCBs, known carcinogens, into the Long Beach and Los Angeles harbors. Zeneca, producer of tamoxifen, demerged from ICI in 1993, and later merged with Astra AB in 1999 to form AstraZeneca. Astra AB had developed the herbicide acetochlor, classified by the EPA as a probable carcinogen. In 1997 Zeneca purchased Salick Health Care, a chain of for-profit outpatient cancer clinics. Subsequently AstraZeneca launched a major publicity campaign encouraging women to assess their risk factors for breast cancer, downplaying the dangers of tamoxifen in order to create a market for its prophylactic, or chemopreventative, use and, more recently, for the breast cancer drug Arimidex (anastrozole), approved in 2002 and used as an alternative to tamoxifen (Arimidex went off patent in 2010).
S. Lochlann Jain (Malignant: How Cancer Becomes Us)