Electromagnetic fields from home wiring, appliances, and power lines do not appear to cause breast cancer, according to a $2.5 million study of more than 1,100 women living in Long Island, N.Y. The study, published today in the online edition of the American Journal of Epidemiology, was part of the much larger Long Island Breast Cancer Study Project, a 10-year, $30 million effort to investigate the environmental causes of breast cancer. After looking at everything from proximity to transformers and high-tension power lines to how often home appliances were used, the researchers were unable to find a connection between electromagnetic fields and breast cancer; other tests conducted as part of the larger study failed to turn up links between breast cancer and exposure to pesticides and other toxic chemicals. The findings, while reassuring to some, were a disappointment to the determined group of local women whose activism convinced the U.S. Congress to fund the research project in 1993 and whose questions about the causes of breast cancer still remain unanswered.