WASHINGTON — Shell Oil Co. and Dow Chemical hid a cancer-causing chemical in two commonly-used pesticides that contaminated the drinking water of millions of people in the state of California, according to lawsuits detailed in a report from the Environmental Working Group earlier this month.
TCP, a poisonous insecticide gas, was used for decades in the pesticide Telone, made by Dow, and D-D, made by Shell.
Shell stopped using D-D in 1984, while Dow ceased usage of Telone during the late 1990s. But “garbage” chemical TCP was found in tap water supplies of about four million people in 13 states between 2013 to 2015, according to the nonprofit group.