Cooking as an Indoor Air Pollution Hazard

Oh, Dear Kitchen!
Could this be true? Instead of associating you with the smell of freshly brewed coffee or a baked sweet pie…here I am with the burnt smell of the word, pollution.

Well, let’s clear the air!

What is air pollution? The picture first to mind? Something outside–smog, busy roads with bumper to bumper traffic, or factories releasing black sooty smoke?
A new study has found that kitchen appliances, especially the oven and stove emit noxious fumes at a rate up to 3x higher than a busy city street.
Scientists at Lawrence Berkeley Lab have identified which indoor air pollutants cause the greatest health consequences.  Poor indoor air quality is as significant as those from all traffic accidents or infectious diseases in the US. The study  reveals that, major source of indoor pollutants in the home is…. cooking.

Yes, cooking. There is no typo here.

The research discovered two pollutants that previously had not been recognized as a cause for concern.
Two new indoor air pollutants have been identified in addition to the three previously known indoor air pollutants—secondhand smoke, radon and formaldehyde.  These are acrolein and PM2.5, or particulate matter less than 2.5 micrometers in diameter.

•  Acrolein is produced  when cooking meats and oils, and we should also mention that it is a genotoxic tissue irritant, that was used as a nerve agent in
  World War I!
• PM2.5 has a variety of sources, including cooking, reactions caused by some cleaning products, any kind of combustion, for example such as burning candles or incense.
  The study addressed only chemical pollutants and did not integrate biological pollutants, such as allergens and molds. Another limitation was that it looked only at exposure through inhalation and not other means of contamination, such as ingestion or skin contact.

However, this research is especially important in light of recent efforts to make buildings airtight to save on energy costs. Airtight homes trap contaminants and worsen the risk of exposure to dangerous chemicals, so new homes should always include a system that introduces fresh air into the home, for instance, by installing a heat or energy recovery ventilator. Scientists at the Energy Department’s Lawrence Berkeley National Laboratory are studying how indoor air quality affects human health and how to remove harmful pollutants from the simple task of everyday cooking.

• Current kitchen ventilation standards and metrics of performance focus on measuring energy use of appliances but not their impact on human health.

Given the information from this new study, it is clear that improved kitchen ventilation is needed.
The Berkeley Lab’s goal is to establish a “science based ventilation standards”. This probably will bring a range of changes such as altering building codes to guarantee effective tools and appliances to improve ventilation in kitchens.

The kitchen is no longer a room where we only cook and eat food. The kitchen is the place where we get together in the morning and after work, the kids often do their homework, and where we proudly entertain. Today’s kitchens more often have no dividing walls and doors to adjacent spaces, open concept is a preferred family home layout.

The unintended side effect of cooking with natural gas: Cooking with gas releases particulate matter, including carbon monoxide, nitrogen dioxide, carbon dioxide and volatile organic compounds. Studies also suggest that natural gas may increase the chances of asthma and respiratory illnesses (David Wimbley, 2000).
In a recent study, Chair of the Dallas based Environmental Health Center, Dr. William Rea concluded that after studying  47,000 patients, the most important sources of indoor pollution responsible for generating (environmental) illness were gas stoves, hot water heaters, and furnaces. Furthermore, gas combustion also provides a transportation mechanism for dust, molds, mites, viruses and bacteria, since water vapour is generated (David Wimbley, 2000).

Natural gas is in its original state contains radon and benzene, chemicals that can contribute to cancer. To add more spice to the already hot dish, a new study in the journal Environmental Health Perspectives has found that natural gas stoves expose us daily – just by cooking supper every night- to unhealthy levels of noxious combustion by-products. Gas stoves and ovens pollute our kitchen’s air with nasties like aldehydes, carbon monoxide and other gases linked to nerve damage and respiratory irritation. While combustion by-products can generally be removed through appliance vents, -again- Energy Star program certifies these appliances for their energy efficiency, but there is not a single standard that dictates how well they have to work or how effective they are at removing pollutants from indoor air.

Are Induction cooktops better for Indoor Air Quality than Gas?

Induction cooktops are safe and reliable alternative to natural gas.
When considering the environmental impacts of gas and induction cooking in our home, the key aspect we need to understand is the fuel source.
With gas stovetops, this is typically natural gas (CH4,methane) for both, commercial and residential kitchens. Induction stovetops use electricity to create an electromagnetic field, and as such have no primary fuel source and do not use combustion as a source of heat. The heat is transferred from the element to the pot or pan on the cooktop, there is no open flame to worry about, therefore makes cooking safer and more energy efficient. Another benefit of induction cooking is that due to the efficiency of how induction cooktops transfer heat, they also heat food faster. This directly reduces cooking time, and therefore energy consumption. The precise temperature control and  instaneous heat of induction stoves are similar to that of gas stoves. However, induction stoves heat more evenly as the cookware transfer the heat directly to the food. .

Providing ample ventilation when we are cooking and correctly using appliances are important control tools we must use. Exhaust fans should always vent to the outdoors over cooking stoves and ranges, and we should pay attention to keep the burners properly adjusted. If our homes are poorly ventilated the odors from cooking will linger and increase the chance of infection.
Basic steps for prevention of air pollution in the kitchen are:

• turning on the fan and opening windows while cooking (weather permitting),
• Removing garbage as often as possible to avoid odors that also attract rodents and insects and prevent food-borne bacteria,
•  Controlling moisture to prevent mold growth,
• Using natural cleaners.

Feature photo by Melanie Fuerer, Pixabay