He believed that constant low-level exposure to TCE had damaged the immune systems of all the members of the Woburn families. “These chemicals always do something,” he told Schlichtmann. “Most of the time they don’t do enough damage for us to notice. You might lose a few cells, but you won’t notice it because we’ve got a lot of extra cells.” A healthy, vigilant immune system will attack and kill aberrant cells. But if the immune system has been damaged, as Levin speculated, a malignant cell stands a far greater chance of surviving and proliferating.

Jonathan Harr, A Civil Action, loc. 655