How would you like a job that involves grocery shopping at Trader Joes with the company credit card and cooking dishes like stir-fry? This describes Tosh Hotchi’s job, but he isn’t a chef. He is part of a research team that studies how to build healthy efficient homes, including how to improve the quality of air inside a home through better ventilation. Hotchi is helping to study a major source of indoor pollutants – cooking.
When people think of air pollution, they usually picture a factory spewing a plume of toxic chemicals. But indoor air pollution causes significant health effects such as respiratory illness, asthma attacks, cancer and premature death. Californians spend over 45 billion dollars each year on these health impacts, according to a study by the California Air Resources Board.
Scientists at the Lawrence Berkeley National Laboratory (Berkeley Lab) have investigated which indoor air pollutants cause the greatest health consequences. In a paper published in Environmental Health Perspectives, they reported that fine particles with a diameter of 2.5 mm or less, formaldehyde and acrolein are the worst indoor contaminants for nonsmoking households.
Fine particulates are found indoors mainly due to cooking, burning candles or incense, and outdoor sources that leak inside. Formaldehyde is mainly emitted by materials used in home construction and furniture, such as particle board, paneling and foam insulation. Acrolein in the home is primarily from cooking, especially oils. All three of these contaminates also come from tobacco smoke.
“Think about what your putting in your home,” says Melissa Lunden, a Berkeley Lab staff engineer. “Most of us have to cook, but do you need the candles, incense and air fresheners? Freshening your air requires taking stuff out, not putting more stuff in.”
Berkeley Lab scientists are now looking for ways to improve indoor air quality, by developing better standards for residential buildings and new tests to measure these hazardous pollutants. Since cooking is a major source of indoor air pollutants, they have also evaluated the effectiveness of cooking exhaust hoods. Their study results showed that indoor air quality can be significantly improved by simply cooking on the back burners of your stove, using higher fan settings, and turning the fan on before you start cooking. Further research on cooking-induced pollutants is underway using a new demonstration kitchen to study real-life cooking conditions. During these studies, Tosh Hotchi’s stir-fry and cookies are just a happy bonus for his coworkers like Melissa Lunden.
For more information about indoor air pollution, check out my KQED Quest blog.