Evaluation of potential short-term exposures to NO₂ from cooking

Abstract

Potential health concerns from cooking with natural gas appliances include short-term exposure to nitrogen dioxide (NO₂). Published, one-hour concentrations measured in a few kitchens during simulated cooking events have been cited as justification for moving to electric alternatives by certain advocates. These estimates, however, are not believed to adequately represent typical potential exposure concentrations. In this paper, the various challenges in evaluating potential exposures based on measured indoor air concentrations of NO₂ associated with cooking are identified and discussed. These include the lack of standards for indoor air in the U.S., the relatively short duration of cooking activities, and the likelihood of bias in indoor NO₂ measurements due to the instrument response to other nitrogen-containing compounds. Correction factors for making more meaningful comparisons are suggested, including correction for duration of cooking time and correction for presence of nitrous acid (HONO).

Keywords:

• Indoor air
• NO₂
• exposure assessment
• cooking
• natural gas

SUSTAINABLE DEVELOPMENT GOALS:

• SDG 7: Affordable and clean energy
• SDG 9: Industry, innovation and infrastructure

Author contributions

Both authors contributed to the manuscript writing, content review, data analysis, and result interpretation. Mr. Eklund performed the calculations depicted in Figures 1 and 2.

The authors prepared this paper during the normal course of their employment at Haley & Aldrich, Inc., a consulting firm that—among other services—provides advice on risk evaluation to private and public clients.

Supplemental online material

Supplemental material related to the exponential rate of decay in an indoor space after cooking is provided.

Notes

1 For example, compliance with the one-hour National Ambient Air Quality Standard (NAAQS) is based on the 98^th percentile of one-hour daily maximum concentrations, averaged over three years. Hence, the standard can be met even with multiple one-hour concentrations over 100 ppb.

Additional information

Funding

Funding for this work was provided by the American Gas Association, an industry trade group.