Found this piece of proposed legislation a couple days ago. The product has to be regulated by by the Food and Drug Administration, the Environmental Protection Agency, the Department of Agriculture, or the Consumer Product Safety Commission for it to apply.
Full Text of H.R. 6601: Carcinogen-Free Label Act of 2012 - GovTrack.us
Full Text of H.R. 6601: Carcinogen-Free Label Act of 2012 - GovTrack.us