Vaping-associated lung illness

The symptoms of vaping-associated lung illness (VALI) are:

• cough
• shortness of breath
• chest pain

People who have these symptoms and who use vaping products should consult a doctor immediately.

A warning against cannabis vaping was published on November 18, 2025. In it, the national director of public health makes recommendations and warns the public against vaping cannabis.

A warning against vaping products with or without nicotine had been published previously on November 25, 2019.

The Ministère de la Santé et des Services sociaux (MSSS), the Institut national de santé publique du Québec (INSPQ), the regional public health directorates, Health Canada and various public health partners are working together to investigate the emergence of VALI in Canada.

As of January 13, 2020, 4 confirmed cases and 2 probable cases have been reported in Québec. A probable case refers to a case where the clinical team believes the patient has developed vaping-associated lung illness but more precise testing could not be done within the time required to rule out beyond a doubt an infection with certain viruses.

Regarding these cases in Québec:

• the patients were between 33 and 85 years old
• the patients used nicotine vaping products from legal sources
• some patients were in the process of quitting smoking
• no patients reported using products containing cannabinoids such as THC or CBD (chemicals found in cannabis)

Although most cases of VALI in the United States seem to be related to vaping products that contained cannabinoids such as THC, the situation could be different in Québec, since the cases reported are not associated with these substances. The situation of cannabis vaping is, however, being monitored closely as it is a source of significant concern.

Information on the number and distribution of VALI cases in Canada can be found on the Government of Canada’s Vaping-associated lung illness page.

The first cases of vaping-associated lung illness (VALI) were reported to the United States Centers for Disease Control and Prevention (CDC) in August 2019 (see Outbreak of Lung Injury Associated with the Use of E-Cigarette, or Vaping Products).

The number of probable or confirmed cases of VALI continues to grow in the United States and is now more than 2000. Several dozen deaths have been confirmed. Eighteen cases have also been reported in Canada. At the moment, the cause(s) of lung injury have not been identified and no compound or ingredient is associated with these illnesses yet. Although vitamin E acetate seems to be linked to some cases of VALI in the United States, evidence is still not sufficient to rule out the contribution of other chemicals to VALI. Many substances and product sources are still being studied.