Study objective: the aim of the study was to analyse the victims and circumstances in carbon monoxide suicides from car exhausts in order to find strategies for mitigation of the suicide risk.
Design: necropsy, police and hospital records were scrutinized for 194 victims who committed suicide by carbon monoxide poisoning from car exhausts during a four-year period in Sweden.
Setting and participants: the State Institutes of Forensic Medicine in Umeå and Stockholm.
Results: a higher incidence (24.2/million population) was seen in the rural region than in the urban region (14.9). Males dominated (88%), most of them middle aged. Most victims committed suicide in a car outdoors. A vacuum cleaner tube connected to the compartment was most commonly used. Severe disease, mostly psychiatric, was seen in 61% of the victims. Drugs were detected in 8% of the victims under psychiatric treatment. In 37%, earlier suicide behaviour was documented. Suicide notes were found in 40%. Blood alcohol was detected in 51% of the victims and other drugs in 7%.
Conclusions: environmental changes may reduce the number of carbon monoxide suicide from car exhausts, e.g. introduction of a law requiring catalyst exhaust, of automatic idling stop, and of exhaust pipes incompatible with vacuum cleaner tubes. The importance of accurate treatment of psychiatric patients is stressed.