Yet monitoring of air quality within the home is scant compared with the outdoor environment.
The Environmental Protection Agency's (EPA) Strive research programme, led by NUI Galway, has carried out an indoor air pollution (IAP) study of homes in Ireland and Scotland where open combustion takes place. This includes all with open fires and homes where smoking takes place indoors. The study measured concentrations of carbon monoxide (CO), carbon dioxide (CO2), endotoxin and nitrogen dioxide (NO2). The measure that was used was PM2.5 (particulate matter up to 2.5 micrometres in size) or the standard measure for potential pollutants.
The good news coming from the study is that there have been advances in the design and construction of homes in recent decades, which have had a good impact on indoor air quality.
As a result, the amount of air entering and leaving a typical building is estimated to be 10 times lower now than it was 30 years ago.
However, evidence as far as the impact of tobacco smoking is concerned is startling in comparison with homes that use coal, wood and peat for heating and gas for cooking.
Concentrations of air pollution in homes using coal, wood, peat and gas for cooking were low, and mostly well within health-based standards.
Similarly, PM2.5 concentrations in homes using coal, wood and gas for heating were comparable to outdoor ambient concentrations. However, peat-burning homes had PM2.5 concentrations approximately twice that of ambient concentrations. Yet, burning peat is by some distance a much safer option than indoor smoking. Homes where smoking takes places had PM2.5 levels 10 times the safe level.
The average 24-hour PM2.5 concentration was almost six times the recommended World Health Organisation (WHO) 24-hour limit and more than four times the US Environmental Protection Agency (EPA) outdoor air quality index "unhealthy" level.
The researchers concluded that “exposure to environmental tobacco smoke represents the greatest impact on health from combustion derived air pollution in the home”.
They then went on to state that the exposure of non-smokers to ETS in the home accounts for a health burden that is “broadly comparable to that currently experienced in both countries from road traffic accidents and there is a real need for public health policy and research professionals to develop interventions to address this”.
The workplace smoking ban was introduced in 2004 and is widely regarded as an outstanding success which has been replicated all over the world.
Minister for Health Dr James Reilly’s assertion that smoking in cars where children are present will be banned is another frontier in the withdrawal of smoking from public places.
However, the private home remains a last bastion of privilege for smokers.
Instead, the EPA report recommends that there should be a co-ordinated national campaign to educate smokers and non-smokers about the health effects of environmental tobacco smoke in the home.
The research was completed by NUI Galway and researchers at the University of Aberdeen, the Institute of Occupational Medicine, Edinburgh, and the University of Birmingham.
NUI Galway research leader Dr Marie Coggins said exposure to tobacco smoke, especially of children, was something that "needs urgent action".
The report’s authors have called for improved national survey campaigns to determine what proportion of the population is exposed to environmental tobacco smoke at home.
Their recommendations include a co-ordinated national campaign to educate smokers and non-smokers about the health effects from smoking at home and the promotion of smoke-free homes.
The Tobacco Free Research Institute Ireland director general Prof Luke Clancy said the results in relation to tobacco smoking were "disappointing". (The institute was formed on the basis of a partnership between the Office of Tobacco Control and Ash Ireland and its parent organisations: The Irish Cancer Society and The Irish Heart Foundation.)
He pointed out that about 40 per cent of Irish children are exposed to second-hand smoke inside households. “Action is needed to encourage people not to smoke or at least not to subject others to the health risks associated with inhaling other people’s smoke,” he said.