Will burning incense or candles in our house harm our 21-month-old?
There is increasing information about the health effects of indoor air pollution. As we hermetically seal our houses to contain both heat and air conditioning, chemical pollutants build up inside. While simple candles probably are not harmful if you burn them for special occasions, frequently burning candles, especially scented ones, or incense is not the best idea, particularly if you have any history in the family of asthma or allergies. There is no regulation to what is used in the manufacture of incense, for example. Not only will your child be inhaling pollutants, but she also may become sensitized or allergic to some components.
On the other hand, using incense or candles outside or in a well-ventilated area such as a screened porch is probably fine.