Whilst some waxes, such as paraffin and gel wax do release paraffin and other toxic chemicals, it is also important to highlight that the European Candle Manufacturers Association (ECMA) has previously stated that no reputable scientific study has shown that candle wax of any kind, including paraffin, is harmful to humans. The ECMA conducted a further study in 2007 that checked all major types of candle wax for 300 toxic chemicals and found that the level of chemicals released would not be harmful to human health.