Relationship Between Vehicle Emissions Laws and Incidence of Suicide by Motor Vehicle Exhaust gas in Australia, 2001-06: an Ecological Analysis

This ecological study tested the relationship between Australian legislation passed in 1986 & 1999 to reduce motor vehicle carbon monoxide emissions & suicide rates. Data on motor vehicle exhaust suicides from 2001-2006 were merged with data on the number & age of vehicles in the national fleet as well as sociodemographic data from the national census. Poisson regression was used to analyse the relationship within 2 levels of geographical area – postcodes & statistical subdivisions – & the population density of pre-1986 & pre-1999 passenger vehicles in those areas. The annual incidence of motor vehicle exhaust suicides nationwide decreased 57% over the study period. Suicide rates were significantly & positively correlated with the presence of older vehicles. (41 refs.)