Warm-weather Wood Burning: Pollution in Our Own Backyards

The weather is heating up, and homeowners are not burning as much wood to stay warm. Now we can all take a deep breath without fear of inhaling wood smoke, right?

Not quite. Unfortunately, the increasing popularity of backyard fire pits and “chimineas” is creating a new reason to worry if you like to breathe clean air. Burning wood in outdoor fire pits and chimineas is just as bad for air quality as burning wood in a fireplace or wood stove. The same pollutants, including particulate matter and dioxin, are produced. Worse, burning wood in the backyard eliminates the “smokestack” that normally releases these pollutants away from ground level; this results in more direct inhalation of the toxins.

Sitting around a camp fire, backyard fire pit, or chiminea thus results in much more immediate, concentrated exposure to harmful particles and since there is not as much opportunity for dispersion. The Canadian Lung Association notes, “Wood smoke from chimineas may stay closer to the ground since they have low chimney stacks and can pose a problem for neighbors.” The upshot is that those in the immediate vicinity of the fire inhale large quantities of wood smoke pollution, and their neighbors get a big dose as well. Children are especially vulnerable, as their respiratory systems are still developing and they breathe more air (and air pollution) per pound of body weight than adults.

While the romance of an outdoor fire is just as alluring as that of a blazing log in the hearth of your living room, please consider the damaging effects of these fires on your health and that of your children and neighbors. We all deserve to have healthy air and to enjoy our backyards without breathing in the pollution from an outdoor fire.

Greenhouse Gases from Wood are a Burning Issue

The International Panel on Climate Change (IPCC) has proven that particles created by burning wood and other biomass—so called “black carbon”—are a major contributor to global warming.

Just like coal, oil, and natural gas, the greenhouse gases (GHGs) sequestered in wood are released to the atmosphere when we burn it for fuel and heat. But while there is agreement that burning wood releases GHGs and creates black carbon, some argue that wood burning is “carbon neutral” because it releases about the same amount of GHGs that is released when a tree decays naturally.

Technically this is true; however, it’s important to consider the factor of time as it relates to burning vs. decaying. It takes over 15 years for a typical tree used for wood burning to mature before it is harvested.  During that time, the tree is storing CO2 that it collects from the atmosphere. Given the opportunity, that tree could live for another hundred years or more, continuing to collect and store GHGs. After it dies naturally, it will take many more years for it to decay and gradually release the GHGs it collected over its lifespan. However, if the tree is burned in a fireplace or woodstove, all those GHGs are released in just a few hours and in higher concentrations.

This difference in timescale is critical. The IPCC has developed a set of projections for the dire effects of climate change. Their report presents a range of scenarios based on how quickly we can reduce our GHG production and how fast we can lower the concentrations of GHGs already in our atmosphere. Many scientists believe that reducing or eliminating wood and other biomass burning to be one of the easiest and most effective ways for us to curb global warming.

The need to reduce deforestation in places like the Amazon and Africa, and in fact the need to plant MORE trees to sequester CO2 and other GHGs, has long been known. But we also need to make the connection to wood burning in our homes here in North America. If we immediately reduce our reliance on wood for heat and break our habit of burning wood for ambiance, we can make a significant contribution to reducing GHGs and black carbon and help avoid some of the most extreme effects of climate change that are predicted by the IPCC.

Wood Smoke Nazis?

Cleaning our air hasn’t been easy. We’ve had to provide proof that air pollution is bad for our health, pass laws, and create new technologies. But our own perceptions and bad habits have proven to be the biggest challenges we’ve had to overcome.

Whenever a new regulation is passed to eliminate or control a source of air pollution, there is an outcry from industry and the public. Some people claim that it is wrong for the government to interfere with private rights, while others protest that such measures are too expensive. Air pollution laws have been called “communist”, “fascist”, and even “Orwellian”.

For example, when trash burning was banned, people were enraged that they couldn’t burn their own garbage in their own backyards. There were complaints about the cost of proper waste disposal. Similarly, when measures were taken to lessen automobile pollution, people were up in arms about catalytic converters and the smog check program, with many claiming that these measures were going to make it too expensive to drive their cars. More recently, people have protested that they have a “constitutional right” to smoke in public places, like restaurants and airports.

Looking back, it seems kind of crazy to think that we as a society fought these laws and regulations. We have seen such drastic improvements in our air quality and our public health that in hindsight, few would argue that these steps were unnecessary or unreasonable.

Wood smoke is a lot like these other types of air pollution. Most people haven’t yet recognized the harm that wood smoke has on public health or the need to reduce its dangerous impact on our air quality. In California, as well as around the country and the world, air quality officials are starting to wake up to the fact that wood smoke is a major source of particulate matter and other pollutants, as well as a major contributor to global warming. As such, it needs to be curbed in order to continue improving our air quality and reduce human contributions to global warming.

Just as people once argued that open garbage burning and cigarette smoking were personal rights and that the resulting smoke was innocuous to the community, they are now decrying regulations against burning wood in fireplaces and wood stoves as invasions of their privacy. Some even compare our public health agencies to Nazis (as seen in this recent local news story).

We at Families for Clean Air believe that ten years from now, when we look back at these early efforts to curb wood burning pollution, we’ll all agree that it was worth our trouble and effort–and that the relatively small impact it had on our habits and wallets was more than worthwhile.

Comparing Wood Smoke Pollution to Diesel Exhaust and Tobacco Smoke

After many exhaustive studies and discussions, The Office of Environmental Health Hazard Assessment (OEHHA) and the California Resources Board (CARB) identified Environmental Tobacco Smoke and Diesel Exhaust as Toxic Air Contaminants (TACs). OEHHA has determined that there are no safe exposure levels for environmental tobacco smoke and particulates from diesel exhaust. So how does wood smoke compare to these other complex pollutants?

FCA recently conducted a direct comparison of the harmful constituents of wood smoke from fireplaces and wood stoves with diesel exhaust and tobacco smoke, and the results are striking. When put side by side, it’s obvious that wood smoke poses many of the same hazards to the public’s health as these two other complex mixtures of pollutants. However, wood smoke has not received the same kind of attention from regulatory agencies like OEHHA, CARB, and the USEPA.

Considering the fact that over one-third of the Bay Area’s winter time particulate pollution comes from wood smoke, it seems obvious that immediate action must be taken to address wood burning in order to protect public health. If it’s going to take more studies and discussions to ensure that wood smoke pollution is reduced in our communities, we say let’s get on with it already!