It is surprising just how much exposure to indoor air pollution most of us have. It has been estimated that people in developed countries spend around 90% of their time indoors, yet how many people do you know who spend 2.5 hours outdoors everyday?
You may head for the wardrobe to get some clothes, perhaps still able to detect the pine smell of the wood and the hint of fabric conditioner on freshly laundered clothes (yet more monoterpenes). Maybe you can smell the carpet. There are compounds in the carpet that react with ozone (from outdoors when you open the window), to give you another dose of chemicals before you even leave the bedroom.
The situation is even more critical in less developed countries, where more than 3 billion people worldwide use solid fuels for energy needs. These fuels are burnt on open fires and traditional fires leading to high levels of indoor air pollution. Indeed the Word Health Report (2002) estimated that indoor air pollution was responsible for 2.7% of the global burden of disease.
The major concern is that such a cocktail of pollutants might have effects on health. In particular, the elderly and the sick who are largely confined to the indoor environment, may be at higher risk of suffering ill-health effects as a result of the accumulation of indoor pollutants. Children may also be especially vulnerable for several reasons: they are more susceptible to chemicals that affect development and lung function; their immune systems are immature and growing organs can more easily be damaged; they inhale more air relative to their size than adults for the same activity level; they are more active than adults. Children can therefore be subject to much higher exposure levels and consequently risk than adults.
One condition that has received much attention in the past is sick building syndrome (SBS), a condition where sufferers have symptoms including eye and nose irritation, headaches, drowsiness, dizziness and reduced powers of concentration. The condition is noted most frequently in new buildings and the symptoms tend to be relived when the affected person leaves the workplace. Childhood asthma cases are also on the increase in the western world, and it has been suggested that indoor air pollution may play a part.
At York, we are investigating the complex chemical pathways that can occur indoors. In particular, it is believed that monoterpenes species emitted from various products such as cleaning solutions, toiletries, furnishings etc. can react with ozone to produce species that cause some of the allergic reactions noted in the indoor environment.
If we can identify the species responsible for causing ill-health effects, it will be possible to make recommendations regarding species removal from certain manufactured products.