The Multnomah County Commission recently issued a paper regarding indoor air quality and natural gas stoves that was used to justify recommending residents replace their natural gas stoves with electric appliances.

NW Natural is unaware of any consultation taken up by the County with experts in the fields of toxicology or epidemiology or relevant medical fields in the development of this report. The result seems to be a paper with hastily prepared messages and recommendations that are being made without the support of robust process and a transparent scientific assessment.

The County also issued its report without any engagement with NW Natural. And unlike members of the media and electrification advocacy groups, NW Natural was not provided with the report in advance.

The County’s report includes assertions often promoted by gas ban advocates that claim natural gas cooking could lead to respiratory illnesses like asthma, especially in children.

However, Dr. Julie E. Goodman, Ph.D., DABT, FACE. ATS, a principal at Gradient, reviewed the County’s presentation summary and provided testimony at the Multnomah County Board meeting, refuting the County’s conclusions (see testimony at 0:02:20). Dr. Goodman is board-certified in toxicology, and a fellow of both the American College of Epidemiology and the Academy of Toxicological Sciences. She has also been on the Board of Health in Canton, Massachusetts, for the last 15 years.

In her testimony, Dr. Goodman referenced the most robust  global study conducted on this topic, The International Study of Asthma and Allergies in Childhood, that evaluated over half a million children from 47 countries, including the U.S., over 5 years – finding no association between gas cooking and asthma in children.[1]/*Wong, GW; Brunekreef, B; Ellwood, P; Anderson, HR; Asher, MI; Crane, J; Lai, CK. 2013. "Cooking fuels and prevalence of asthma: A global analysis of phase three of the International Study of Asthma and Allergies in Childhood (ISAAC)." ISAAC Phase Three Study Group, available at https://pubmed.ncbi.nlm.nih.gov/24429203/*/

This study was not referenced or evaluated in the County’s report.

Due to claims circulated in the media, there are a few items about which we would like to provide additional information and context: 

  • No federal agency, including the EPA, has determined it necessary to set indoor air quality standards for gas appliances.
  • Multiple studies[2]Logue et al. (2014) and Singer et al. (2017) demonstrate that ventilation plays an important role in mitigating cooking-related air emissions that come from both gas and electric stoves. This is why kitchen exhausts are required for all new homes in Oregon, whether they have gas or electric cooking. Government agencies and peer-reviewed scientific studies agree that proper ventilation when cooking is key to mitigating cooking related emissions, whether you are cooking with a gas or electric stove, because cooking activities themselves (e.g., grilling, frying, broiling, baking) are a source of indoor air emissions.
  • While acknowledging cooking--no matter the fuel type--has some form of emissions, the County focused solely on gas appliances in its recommendations, ignoring that ventilation is important to any form of cooking.  
  • The study the County references to support the quote, “Children living in homes that cook with gas are 42% more likely to experience symptoms associated with asthma…” is problematic and inconsistent from a scientific perspective. According to a review by Gradient, “The Lin et al. (2013) study reported weak, statistically significant associations[3]https://www.aga.org/globalassets/research--insights/gradient-ama-resolution-439-letter.pdf between gas cooking and asthma and between indoor NO2 and wheeze; however, there was no statistically significant increased risk of wheeze in relation to gas cooking or risk of asthma in relation to indoor NO2. This study also had a number of important limitations, including heavy reliance on older cross-sectional study data and the use of data from a heterogeneous set of studies in terms of locations, home characteristics, and ventilation, without any assessment of study quality.”  

Epidemiology is a complex field and ensuring accurate information requires sound research methodology and an objective interpretation of the data to arrive at helpful recommendations. NW Natural turns to technically trained scientific experts in the field of epidemiology for learnings and guidance on indoor air quality. 
Although to date NW Natural has been excluded from the County’s efforts on this important subject, we welcome the opportunity to have a seat at the table as the discussion continues.  

Correcting the record on emissions

The County’s paper implies using electricity is fossil fuel free. That is not the case for cooking or anything else. Oregon electric utilities rely on about as much natural gas for power generation as all the natural gas utilities in the state combined.[4]In 2021, Oregon’s natural gas deliveries for electric power was 140.1 Bcf. Natural gas deliveries for residential, commercial and industrial sectors were 134.5 Bcf. Source: EIA annual natural gas deliveries to consumers, Oregon, 2021, available at: https://www.eia.gov/beta/states/states/or/data/dashboard/consumption About 27% of Oregon’s power generation still relies on coal as well.
In Oregon, 29% of GHG emissions are from electricity; 6% is associated with all the gas use by our residential and commercial customers.[5]Oregon DEQ In-Boundary GHG Inventory 2019 data

The emissions from electric generation and its impact on air quality were not mentioned in the County’s report.

Discover More

Destination Zero.

Our vision is to champion new technologies and innovative policies that enable a carbon-neutral energy system.

Learn More
No-cost, low-cost efficiency tips.

Read tips that can help you improve energy efficiency and lower your monthly bill.

See tips
Learn about Less We Can.

Let's work together to make a low-carbon, renewable energy future a reality.

Start now