The city’s medical officer of health is concerned about the growing number of places in Toronto where indoor waterpipe smoking is taking place.

Dr. David McKeown is the author of a new report that outlines the health risks that come with the use of waterpipes indoors.

These waterpipes, called hookahs, can be found in dozens of bars, cafes and other establishments across the city. They can be used to smoke moist tobacco or shisha — a herbal product that is not tobacco and which is sometimes sweetened or mixed with fruit.

While smoking tobacco has been banned in Ontario’s workplaces and enclosed public spaces for years, there is no such provincial ban on the indoor use of waterpipes for herbal, non-tobacco products.

McKeown’s report warns that even if people are smoking non-tobacco products in these waterpipes, the process may be harmful to one’s health, as well as those in the vicinity when they are being used.

Jeffe Penny runs a College Street shop that sells the kind of waterpipes that McKeown is concerned about.

He acknowledges that many people assume it is safe.

"People have this sense that it’s not dangerous because it’s not tobacco, like, you have to really think about the fact that you are burning something and inhaling the smoke from it," Penny said.

But McKeown said that it’s something that members of the public "should be looking at it carefully from a health point of view."

His report indicates that there is emerging research indicating that indoor waterpipe use involving non-tobacco or herbal substances “has an adverse impact on indoor air quality that can lead to unhealthy exposures.”

The report also says that similar concerns are shared by other public health agencies in Ontario that indoors waterpipe use "poses a health risk to the user of people exposed to the smoke."

McKeown also points out in his report that in other cities, including in Barrie, Ont., waterpipe bars and cafés have been banned.

He wants public consultations to take place, in order to determine whether they should also be banned in Toronto. McKeown is asking that a report come back on the matter by the end of the year.