An unusual case of carbon monoxide poisoning

Carbon monoxide, a gas originating from incomplete combustion of carbon-bas ed fuels, is an important cause of human deaths. In this paper, we describe an unusual carbon monoxide poisoning in a dwelling without obvious sources of combustion gases, for which two adults had to be treated in a hyperbari c chamber. Carbon monoxide readings were taken in the house and in the neig hboring homes. Methane gas and nitrogen oxide levels were also monitored in the house air. Soil samples were collected around the house and tested for hydrocarbon residues. The investigation revealed the presence of a pocket of carbon monoxide under the foundation of the house. The first readings re vealed carbon monoxide levels of 500 ppm in the basement. The contamination lasted for a week. The investigation indicated that the probable source of contamination was the use of explosives at a nearby rain sewer constructio n site. The use of explosives in a residential area can constitute a major source of carbon monoxide for the neighboring populations. This must be inv estigated, and public health authorities, primary-care physicians, governme ntal authorities, and users and manufacturers of explosives must be made aw are of this problem.