There are many products that we use in our homes every day that will cause us to develop allergies and asthma. It all has to do with our systems and how long we are exposed to these products. Most of the time it is long term exposture to low quanties of pollutants that is the cause.
Pet dander. VOC's from cleaning products, and air fresheners will set my allergies off. Not everyone will react the same in a home. It is hard for others that are not effected by these pollutants to understand what you are going through.
Here is an example and the information came from the E.P.A. Air Fresheners! What is in it? There are four basic ingredients in air freseners. FORMALDEHYDE, PETROLEUM DISTILLATES, P-DICHLOROBENZENE, and PROPELLANTS.
Why are these so bad? The first ngredient is a suspected carginogen and a strong irriant to the eyes, throat, skin and lungs. The second ingredient can irratate the eyes, skin, respiatory tract; may cause fatal pulmonary edema; and is flammable. Third ingrediant has vapor that is irritating to the skin, eyes, and throat, causes liver damage in animal studies. The final ingrediant is either associated with brain damage or highly flammable.
All of this just to have your home smell fresh? Post your comment and if you like my research, I will be glad to expand my findings to this post.