Wood burning stoves are a health hazard. Period. Not debatable. To understand, we first have to examine what combustion is all about. When cellulose and lignin, the major components of wood, burn completely, they produce carbon dioxide, water, heat and light. The heat of combustion also allows oxygen and nitrogen in the air to form various oxides of nitrogen. But combustion is rarely complete. Smoke is a sign of incomplete combustion…and of a health risk. It is actually composed of tiny particles of unburned hydrocarbons which are packed with carcinogens such as the notorious polycyclic aromatic hydrocarbons (PAHs). Incomplete combustion also signals the formation of carbon monoxide.
Inhalation of carbon monoxide reduces the blood’s ability to supply oxygen to the body. Nitrogen oxides directly impair the respiratory system and also contribute to ozone formation, which causes breathing problems. Ozone is formed when nitrogen oxides are mixed with some of the volatile organic compounds such as formaldehyde that are also produced when wood burns.
According to the California Environmental Protection Agency, the particulate matter emitted from wood burning is usually 10 or 2.5 microns in diameter. In order to put this into perspective, a human hair diameter is roughly 60 microns! Due to their miniscule size, these tiny particles can easily lodge in the lungs causing asthmatic attacks, severe bronchitis, cardiovascular diseases and respiratory illnesses.
Cooking indoors on a wood burning smoke is particularly dangerous. However, some studies have suggested that HEPA (high efficiency particulate arresting) filters may be a viable option for reducing particle concentrations in homes. But HEPA filters cannot filter out volatile organic compounds. Furthermore, it should be realized that fireplaces and old woodstoves are inefficient, expensive heaters. This is because of the way wood burns. In fact, 90% of the heat created by burning wood in a fireplace escapes through the chimney. Switching to more energy efficient methods such as electric or gas fireplaces and/or pellet stoves is the way to go. Not only will you be warmer, but also you need not worry about triggering asthmatic attacks or inhaling microscopic air particulates that can have long term consequences.