TORONTO -- Researchers at the University of Miami are dispelling claims that wearing a face mask can increase a person’s carbon dioxide levels.

In a new study published in the journal Annals of the American Thoracic Society (ATS), researchers examined the breathing of 15 healthy physicians without lung conditions and 15 veterans living with chronic obstructive pulmonary disease (COPD).

In order to assess the changes in oxygen and carbon dioxide levels, researchers compared the breathing of each individual before and after wearing a surgical mask through a six-minute walking test.

During the walk, subjects with severe COPD experienced decreased oxygenation as expected by the researchers. However, at the five-minute mark and 30 minutes after the walk, researchers found no major changes in oxygen saturation or carbon dioxide levels with either group.

"We show that the effects are minimal at most even in people with very severe lung impairment," Dr. Michael Campos of the Miami Veterans Administration Medical Center and the Division of Pulmonary, Allergy, Critical Care and Sleep Medicine at the University of Miami said in a statement.

When asked about the discomfort felt by some people when wearing a mask, Dr. Campos explained: "The feeling of shortness of breath, felt with masks by some is not synonymous [with] alterations in gas exchange. It likely occurs from restriction of air flow with the mask in particular when higher ventilation is needed (on exertion)."

The use of face masks has become a highly politicized issue throughout the pandemic, with some individuals falsely claiming that wearing a mask can negatively impact a person’s breathing and put their health at-risk.

Scientists and disease experts have attempted to eradicate COVID-19 conspiracy theories by reassuring the public that face coverings can safely and effectively prevent the spread of COVID-19 respiratory droplets. Despite these efforts some people are still not persuaded.

Anti-mask groups have been holding rallies in cities across Canada in objection to pandemic-related restrictions. Demonstrators have continuously questioned the effectiveness of mask wearing and social distancing practices with regard to curbing the spread of the virus.

According to data from a survey conducted by Statistics Canada, about 84 per cent of Canadians said they wore a mask or other kind of personal protective equipment in July. In a previous study conducted in June, only 65 per cent of Canadians reported wearing a mask in public spaces where physical distancing was difficult.

"We acknowledge that our observations may be limited by sample size, however our population offers a clear signal on the nil effect of surgical masks on relevant physiological changes in gas exchange under routine circumstances (prolonged rest, brief walking)," the ATS study says.

"It is important to inform the public that the discomfort associated with mask use should not lead to unsubstantiated safety concerns as this may attenuate the application of a practice proven to improve public health."