A former British Air Force sergeant has joined a lawsuit in West Virginia that claims that British and American troops were knowingly exposed to a toxic chemical by a government contractor in Iraq in 2003. According to the lawsuit, KBR Inc. knew of the high levels of sodium dichromate, a potent carcinogen, at the Qarmat Ali water-treatment plant months before they informed American and British troops guarding the facility. The lawsuit also claims that KBR officials discussed the exposure in an August 2003 meeting, but kept the site running for another month. The victims suffered from severe rashes and nose bleeds, and some developed tumors.