Most people spend more than 75 percent of their time inside, so their exposure to many common air pollutants is determined by the level of these substances found inside rather than outside. Air quality in a building will vary widely from one building to another depending on a variety of factors, including the production of chemicals and gases emitted from heating devices, internal fittings, and structural components. Another important factor in determining the level pf air pollution inside is the rate of removal of these substances, which depends on how well your home is ventilated.
The predominant pollutants, in general, act as irritants but they can also exaggerate allergic reactions to indoor allergens and make symptoms worse. The sources of these pollutants include gas cookers (ranges), portable gas heaters, and wood-burning fireplaces, which all give off nitrogen dioxide. Sulphur dioxide, another problem indoor gas, comes from burning coal in open fires or from oil and paraffin heaters. Additionally, within the typical home environment are volatile organic compounds (VOCs), such as formaldehyde, which may be associated with respiratory problems (runny or blocked nose, coughs, and wheezing) and itchy skin.
Volatile organic compounds (VOCs)
These compounds are a group of chemicals based on the carbon atom (organic) that evaporate rapidly (volatile). There are many chemicals that fall into the VOC category, and in general they act as irritants – although a small percentage of allergy sufferers develop a specific immune response to VOCs, especially formaldehyde. Some VOCs occur naturally, such as when an orange is cut, while others are synthetic and are contained in manufactured products, some common examples of which are listed here:
• Glues and solvents
• Board-based furniture
• Cleaning products
• Insulation material
• New carpets and some flooring
• Aerosol products
• Air fresheners
• Dry-cleaned garments
• Some synthetic fabrics
• Wood preservatives
• Paints – especially some gloss types
Inhalation of second hand smoke fumes (passive smoking) is harmful to young children because it increases both their risk of developing a respiratory infection and their risk of developing an allergic tendency. It also potentially predisposes them to the development of asthma.
In addition, the presence of tobacco smoke pollutants within the air act as irritants to worsen preexisting allergic diseases. Thus, going into a smoky environment will make the eyes sore and water in individuals with conjunctivitis, worsen nasal blockage in those with rhinitis, and may induce chest tightness, wheeze, and cough in people with asthma.
Thus, for children living with parents who smoke, the constant exposure to airborne tobacco pollution will worsen the children’s allergic conditions, whether this is asthma, rhinitis, or conjunctivitis, and thus stronger maintenance treatment will be necessary than in a nonsmoking home.