Detoxification of Motor Vehicle Exhaust and Suicide

Abstract

Lester and Murrell ( 1980) have argued that restricting the availability of the means for completing suicide may be an excellent way of preventing suicide. They reported that stricter handgun controls in the 48 continental states were associated with a lowered suicide rate. Recent data on the effects of emission controls on automobiles in the USA are consistent with this idea. Landers ( 1981) noted that the carbon monoxide content of car exhaust was 8.5% before 1968, 3.0% during 1975-1979, and 0.5% by 1980. While thc numter of people killing themselves using motor vehicle exhaust gases in the USA has remained roughly constant from 1965 to 1979 (2120 in 1965 and 1929 in 1979), the total number of suicides has risen in the same period from 21,501 in 1965 to 27,206 in 1979. Thus, che percentage of suicides using motor vehicle exhaust has dropped from 9.9% in 1965 to 7.1% in 1979. As motor vehicle exhaust in the USA has become less toxic, a smaller percentage of suicides seem to be using it as a means of killing themselves. This makes an interesting contrast with the situation in Britain where car exhaust suicides have more than tripled during the same period (Bulusu & Alderson, 1984). This may to some extent reflect increased ownership of cars, more homes with garages and possibly the increased popularity of hatchback and estate cars which permit rhe easier introduction of the exhaust gases into the passenger compartment. Another possible reason is that knowledge about this method of suicide has spread.