Changing rates of suicide by car exhaust in men and women in the United States after car exhaust was detoxified.

The rates of men and women committing suicide by using car exhaust responded differently to the imposition of emission controls on cars. The male rate dropped immediately after emission controls were imposed, whereas that of females continued to rise. Eventually both rates dropped until the early 1980s, whereupon they began to rise again slightly. The implications of these findings are discussed.