The Cancer Chronicles: Erin Brockovich and Mother Jones

Erin Brockovich in 2012. Wikimedia Commons. When toxicologists prepare to test a chemical on lab animals to see if it is carcinogenic, they are faced with a dilemma. Suppose you have reason to suspect that a chemical, at the low concentrations found in air, food, or water, might cause one case of cancer for every 10,000 people who are exposed. You’re not going to get funding to test every substance on tens of thousands of mice -- at a potential cost of tens of millions of dollars. To force the issue, scientists administer far larger dosages to a far smaller number of creatures and see if they can induce a tumor. That is the approach -- prevalent throughout the profession -- taken by researchers for the National Toxicology Program in 2009 to study whether chromium 6, the pollutant involved in the Erin Brockovich case, is capable of causing cancer when ...