Carbon monoxide: The invisible killer

Carbon monoxide (CO) is a colourless, odourless and tasteless gas. It is em itted when carbon containing compounds are incompletely combusted. This pap er reports on concentrations of CO in the environment in relation to anthro pogenic emission sources and assesses the extent of the health hazard from this common air pollutant. It includes the results of CO monitoring in a va riety of locations in south west London. The conclusion is that indoor emis sion sources present a greater and more insidious health risk than do outdo or emission sources. Methods for reducing the dangers it poses are briefly summarised.