Do dogs change the air around us?
Daily life as a mammal causes emissions to be released into the atmosphere. Humans, for example, breath out carbon dioxide and volatile organic compounds, while shedding skin cells and releasing ammonia.
Although we invited dogs into our homes over ten thousand years ago, no study has ever explored how living with man’s best friend changes indoor atmospheres. A new paper in Environmental Science and Technology addresses this gap by looking at the particles, bacteria and fungi emitted by pet dogs.
The authors studied two groups of dogs: 4 small dogs (all Chihuahuas) and 3 big dogs (Tibetan Mastiff, Newfoundland, and Mastiff). Each group entered a specially designed climate chamber with their owner for 2 hours, including scheduled petting time and playing to mimic regular activity.
Environmental pollutants were measured for both groups and compared to human-only emissions, showing that:
- Dogs emit carbon dioxide, ammonia, volatile organic compounds and particulate matter at a similar or higher rate than adult humans
- Big dogs emit at a much higher rate than small dogs
- Emissions come from both bodily processes and external sources
- Dogs significantly changed the microbes in the air
Why does this matter?
Around a third of households globally have a dog. As a result, it is important to understand how canines change indoor air quality and cause exposure to pollutants that impact human and pet health. By characterising atmospheric variations from dogs and other pets, measures can be taken to improve air quality for everyone in a household.
Read the full paper here: https://doi.org/10.1021/acs.est.5c13324 from the American Chemical Society (dog pictures available in the SI!)
Shen Yang, Nijing Wang, Tatjana Arnoldi-Meadows, Gabriel Bekö, Meixia Zhang, Marouane Merizak, Pawel Wargocki, Jonathan Williams, Martin Täubel, and Dusan Licina, Our Best Friends: How Dogs Alter Indoor Air Quality, Environ. Sci. Technol., 2026