Possible carcinogen is a category of the dangers of chemical exposure as recognized by the United States Environmental Protection Agency‎ (EPA).

This is as opposed to "probable" or "known" carcinogen under EPA classifications of carcinogenicity.

As of 2011 approximately 900 agents have been studied to determine if they are carcinogenic, with 267 being classified as possibly carcinogenic to humans as opposed to only 1 being classified as probably not carcinogenic to humans. Agents currently listed as possible carcinogens include: coffee, coconut oil, cobalt, and nickel.

In 2002 the EPA found that diesel is a "probable" carcinogen. [1].

http://library.findlaw.com/1999/Jul/27/126283.html http://www.cbsnews.com/stories/2002/08/29/health/main520195.shtml

The Residents are an American art collective best known for avant-garde music and multimedia works. The first official release under the name of The Residents was in 1972, and the group has since released over sixty albums, numerous music videos and short films, three CD-ROM projects and ten DVDs. They have undertaken seven major world tours and scored multiple films. Pioneers in exploring the potential of CD-ROM and similar technologies, The Residents have won several awards for their multimedia projects. Ralph Records, a record label focusing on avant-garde music, was started by The Residents.

Throughout the group's existence, the individual members have ostensibly attempted to operate under anonymity, preferring instead to have attention focused on their art output. Much outside speculation and rumor has focused on this aspect of the group. In public, the group appears silent and costumed, often wearing eyeball helmets, top hats and tuxedos - a long-lasting costume now recognized as their signature iconography. Their albums generally fall into two categories: deconstructions of Western popular music, or complex conceptual pieces, composed around a theme, theory or plot. They are noted for surrealistic lyrics and sound, disregard for conventional music composition, and the over the top, theatrical spectacle of their live performances.