Many people burn candles for decoration. Soft candlelight is very romantic, and the wafting scent of a candle can be relaxing while in the bath. If the power goes out, candles are a must. If there is a birthday, candles are burning on the cake. With candles a positive part of their lives, not many people stop to consider that burning them may be bad for their health.
The vast majority of candles are made from paraffin wax. When paraffin melts, it releases traces of various organic chemicals, including formaldehyde. In addition, the smoke from candles can coat every item in a room with a fine layer of residue called black soot. Candle smoke burns clearly, but that doesn’t mean that it isn’t there; the yellow color of a candle’s flame is the byproduct of the fuels the candle needs to burn not completely being eaten up in the process. The excess bits of material turn into black soot and settle around your house!
While airborne, black soot can filter through your air conditioner; it can be inhaled like any other airborne particle, coming to rest inside the deepest parts of your lungs. Bearing in mind that black soot can gather so thickly that gravity will make it fall from wherever it has built up in your house, imagine how much there is in your lungs if you frequently burn candles?
In addition to the effects of burning paraffin, there is a very real danger in the materials used to make candle wicks. Lead used to be the standard material used to make a wick stiff, until around 1970 when people realized that burning a wick full of lead meant that the candle user was breathing it in. Common materials for candle wicks as of 2010 are zinc and tin, neither of which are supposed to be dangerous to inhale. Inhaling too much zinc can cause metal fume fever, a flu-like disease that can take four days to recover from. More severe symptoms include convulsions, collapse, vomiting, bloody diarrhea and more, and require a visit to the emergency room for medical treatment.