The primary benefit of using cotton candle wicks is that they are non-toxic, considered the safest for burning and have no dangerous health effects. Cotton wicks and other non-cored wicks, such as hemp wicks, contain braided or twisted plant fiber, while cored wicks contain a metal core. Some of the metals found in cored wicks include tin, zinc and lead.
Even wicks with metal cores generally have a cotton component on the outside. Metal-based wicks with lead are a leading cause of lead poisoning, and zinc-cored wicks may also pose a threat. The National Candle Association stopped the production of lead-core wicks in 1974 due to health concerns around airborne lead and lead on home surfaces. Many countries still allow production of lead-cored wicks. Many retailers in the United States also continue to sell zinc-cored wicks.
Cotton wicks benefit the safety of the home and avoid the release of dangerous metals into the environment. Tests show that candles containing small amounts of lead produce enough air lead concentration in just 45 minutes to exceed the recommended daily limit for a normal, active 6-year-old. The only reliable method to distinguish lead-containing wicks from non-cored cotton wicks is product information and thorough research.