Household Chemicals
Some studies have indicated that formaldehyde; a chemical gas can trigger asthma. Formaldehyde irritates the eyes, nose and the lungs. It is used as a preservative in processed foods, cosmetics, shampoo, etc. It is also used to manufacture plastics, some types of fabric and building materials such as plywood, pressed board, carpet backing, glue, foam, etc.Perfume: If you develop cough, wheezing or tightness in the chest while in the company of people who use perfumes, it means that you are allergic to perfumes. The symptoms can develop even if you are exposed to some strong smell for a short time, such as in an elevator, shopping areas, bus stop, etc.

Smoke: Exposure to gases that are released during burning of coal, wood, kerosene, natural gas, etc, can lead to an asthmatic attack. This is because burning produces a wide range of irritant gases such as carbon dioxide, carbon monoxide, nitrogen oxide, nitrogen dioxide and sulphur dioxide.

Some other household gases or smells can trigger symptoms of asthma. For example, isocyanate released from paints and fluorocarbon propellants can cause allergic reactions in sensitive people. Fluorocarbon propellants are present in hair sprays, deodorants, insecticides, room fresheners, cleaning sprays, etc. The risk of developing allergic reactions to these household chemicals is greater if there is inadequate circulation of fresh air in the house