Wood-burning restaurants

Restaurants with wood-burning ovens are a growing public health concern.

Situated in or near business districts, shopping centers and residential neighborhoods, they emit wood smoke pollution in areas where people walk, shop, work and live.

Commercial wood-burning ovens are often left smoldering all day, even when not in use, and sometimes even overnight so that the stone will remain hot. The insurance industry warns this also increases fire risk.

Expensive damage next door

In Pittsburgh, Pennsylvania a restaurant with a wood-burning oven caused an estimated $10,000 in damage to a neighboring church’s organ, and filled their premises with smoke so often that the church’s smoke detector kept going off.

Emissions filters added, but the problem remains

Some restaurants add expensive equipment to filter their emissions, such as a New York wood-burning eatery whose proprietors spent hundreds of thousands of dollars in an attempt to mitigate their wood smoke emissions problem. In that case, the neighbors continued to complain about the smoke and, in spite of the expensive mitigation efforts, the restaurant eventually closed.

Smoke from a wood and charcoal-burning restaurant in Cambridge, Massachusetts, negatively impacted the quality of life and health of neighboring residents. The owners spent over $100,000 on equipment to reduce smoke emissions, but the filtration system didn’t work as expected, and the problem continued. The city’s Commissioner of Public Health eventually ordered the restaurant to stop burning wood and charcoal, finding that the restaurant’s emissions “caused a condition of nuisance… and/or a condition causing sickness which is injurious to the public health.” The restaurant appealed, but was overruled.

Cigarette smoking was banned in restaurants to protect public and employee health. Now an increasing number of restaurants are burning wood, which can fill an entire shopping area or neighborhood with smoke.

The new secondhand smoke in restaurants

Cigarette smoking has been banned inside restaurants in order to protect employees and customers from secondhand smoke. Yet few seem to question smoke inside wood-burning restaurants, which poses similar health hazards.

An earlier review of the Cambridge restaurant noted its “focal point is the hearth at back, food charring on grates, logs ablaze. (The chef poking at them, eyes red and tearing, suffers so your food may be infused with smoke. Someone get him some eye protection… )”

An Italian study of pizzerias with wood-burning ovens found that PM1 concentrations inside the restaurants “can be very high, especially when compared to other critical microenvironments” including urban freeways.

Indoor ventilation and filtration systems have been found to be ineffective in eliminating the health risks posed by secondhand cigarette smoke. The only effective method of eliminating this health hazard is to prohibit smoking. There is no reason to believe that the situation is substantially different with smoke produced by burning wood or other solid fuels.

Fine particle concentrations inside pizzerias with wood-burning ovens can be “very high.”

Wood-burning restaurants cause harmful air pollution

Another Italian study found that airborne levels of the carcinogen benzo(a)pyrene were highest in outlying areas where wood is burned, rather than in more urban areas. The exception was in urban Milan, where elevated benzo(a)pyrene levels were associated with the presence of wood-fired pizzerias.

A study in São Paulo, Brazil, found that an average wood-burning pizzeria burns 48 metric tons of wood each year. In total, 7.5 hectares of eucalyptus forest are burned there annually by pizzerias and other wood-burning restaurants. Not only is this harmful for forests, but burning that much wood also adds significantly to air pollution levels. The study’s authors point out that the health effects from pizzeria and barbecue emissions are higher than those from industrial sources, in part because pizzerias and barbecues have chimneys much closer to ground level and release pollutants all year long in populated areas.

Montreal’s wood-burning pizzerias, bagel bakeries and grilled chicken restaurants that burn wood and charcoal are estimated to emit 60 metric tons of fine particle pollution each year, creating serious impacts for the neighbors of these establishments.

A study of emissions from wood-burning pizza ovens in Italy concluded it’s “of the upmost importance” to introduce regulations on the wood-burning restaurant sector in order to protect and improve air quality.

Some of the highest PAH levels found in foods have been in those that were cooked with open flames, including pizzas from wood-burning ovens and barbecued meats.

Seasoned with carcinogens

For those eating the food, there is evidence that they are harmed as well. Wood-grilled and smoked foods contain elevated levels of heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs). These  compounds are mutagenic—they can damage DNA as they are metabolized in the body.

There is evidence that regularly eating food prepared this way increases the risk of cancer. As the United States National Cancer Institute tells us, “PAHs are formed when fat and juices from meat grilled directly over a heated surface or open fire drip onto the surface or fire, causing flames and smoke. The smoke contains PAHs that then adhere to the surface of the meat. PAHs can also be formed during other food preparation processes, such as smoking of meats.” (For more on PAHs, please see our Wood Smoke Is Toxic Pollution page.)

It has been noted that some of the highest PAH levels found in foods have been in those that were cooked with open flames, including pizzas from wood-burning ovens and barbecued meats.

Smoked meat is “contaminated meat”

An article on the website for the Cleveland Clinic notes, “In short, smoked meat is contaminated meat.” They point out that smoked cheeses contain harmful PAHs too.

Smoke, whether consumed as residue on food or inhaled as air pollution, is not healthy.