Polychlorinated biphenyls, or PCBs, have been linked to cancer, specifically non-Hodgkin's Lymphoma. Check out this video where The Non-Hodgkin's Project explains this magical relationship between this poisonous group of chemicals and NHL:
The Non-Hodgkin's Project is all about exposing this link, as well as forcing Monsanto to acknowledge responsibility for this issue. According to The Non-Hodgkin's site, Monsanto "the controversial biotechnology company, manufactured 99 percent of all the PCBs produced in the United States." If you would like to sign a petition telling Monsanto just this, click here.