Environmentalists and healthcare experts warn that burning wood for fuel triples the levels of harmful air particles in the home. Scientists say that when the doors to the burners open for refueling, these tiny particles of air pollution flood into the home and can trigger a wide range of health problems for residents as they pass through the lungs. The elderly and the very young are particularly vulnerable.

According to The Guardian, experts at Asthma UK and the British Lung Foundation ask people not to use wood burning stoves or heaters unless that have no alternative.

“We know that burning wood and coal releases particle matter called PM2.5, the most worrisome form of air pollution for human health,” said Sarah MacFadyen, head of policy and public affairs at the Foundation.

The American Lung Association warns that while curling up with a cup of cocoa and a good book in front of a roaring fire may seem like a cozy and quaint thing to do this winter, it’s extremely dangerous. The tiny particles of pollution emitted can go straight into the organs through the lungs.

Research shows that air pollution damages every organ of the body, especially the lungs, and can increase the risk for depression and dementia, according to experts. Dr. Nick Hopkinson, medical director for the Foundation, added, “To protect yourself and others around you, especially children who are particularly vulnerable as their lungs are smaller and still developing, avoid buying a wood-burning stove or using an open fire if you have another source of fuel to cook and heat your home with.”

The American Lung Association said that wood smoke can cause coughing, wheezing, and asthma attacks as well as more serious issues such as heart attacks, lung cancer, and premature death. More and more communities across North America are moving to ban wood and coal-burning fireplaces, and in some areas it is prohibited as activists and governments consider them a threat to public health.