Let us begin with a case example of an environmental intervention strategy demonstrating cancer risk reductions.

Case 2:  Childhood Leukemias in Woburn, Massachusetts

Some may be familiar with the movie A Civil Action, which documented the cluster of childhood leukemias in Woburn, Massachusetts. Several wells supplied drinking water for the town. Wells G and H were located near industrial activity, including tanneries using heavy metals, chemical and pesticide manufacturers, and dry cleaners using chlorinated solvents. These industries dumped their chemical wastes near Wells G and H decades before the wells began to be used for drinking water before the U.S. Environmental Protection Agency was established in 1970. In the early 1970s, a 3 ½-year-old boy in Woburn was diagnosed with leukemia. After visits with neighbors, the family learned of 2 other cases of childhood leukemia a few blocks away.  

By 1979, 12 cases of childhood leukemia had been identified in a 15-year period, which was higher than expected. Wells G and H were shut down that year, and several health studies were conducted. A follow-up case-control study conducted decades after the closure of the wells revealed that when mothers drank water supplied by Wells G and H, their children had an 8-fold increased risk of developing leukemia (Costas et al. 2002). By turning off the contaminated wells, childhood leukemia cases fell back to below-expected rates when considering the latency period for the disease.

When we intervene and stop toxic exposures, we can prevent cancer.