On March 31, 2021, former New York state Gov. Andrew Cuomo passed the Marijuana Regulation and Tax Act legalizing adult use and possession of cannabis. To New Yorkers, this means that smoking and vaping cannabis now falls under the Clean Indoor Air Act, which effectively makes it legal to use anywhere it’s legal to smoke and vape tobacco.

The good news, thanks to the act, is that residents won’t be lighting up (or vaping up) cannabis in almost all public and private indoor workplaces, including restaurants and bars, to protect employees and fellow citizens from being exposed to harmful secondhand tobacco smoke, vaping aerosols and now — secondhand marijuana smoke (and its stinky smell).

To understand the potential public health outcomes of the new secondhand smoke, let’s begin with what we know. Tobacco smoke contains more than 7,000 chemicals, including about 70 that can cause cancer. Exposure to secondhand smoke (even briefly) can cause illness and death in infants, children and adults. It can cause bronchitis, pneumonia and ear infections in children and more frequent attacks in children who have asthma. The Centers for Disease and Prevention Control (CDC) states that since 1964, 2.5 million non-smokers have died from health problems caused by secondhand smoke exposure.

The emissions created by e-cigarettes can also contain ingredients that are potentially harmful to public health, including nicotine, ultrafine particles, flavorings (such as diacetyl, a chemical linked to serious lung disease), volatile organic compounds (such as benzene, which is found in car exhaust) and heavy metals (such as nickel, tin and lead).

The dangers of smoking cigarettes have long been known, but what do we know about smoking cannabis? Not a lot, unfortunately, since cannabis use is still illegal on the federal level.

What we do know is that secondhand marijuana smoke contains many of the same cancer-causing substances and toxic chemicals as secondhand tobacco smoke. Some of the known carcinogens or toxins present in marijuana smoke include: acetaldehyde, ammonia arsenic, benzene, cadmium, chromium, formaldehyde, hydrogen cyanide, isoprene, lead, mercury, nickel, and quinoline. People who are exposed to secondhand marijuana smoke can have detectable levels of THC (tetrahydrocannabinol) in their blood and urine.

Conclusion: Secondhand marijuana smoke and secondhand tobacco smoke are similar in many ways. While additional research and scientific evidence are needed to provide facts, the current body of science shows that both tobacco and marijuana smoke have similar chemical composition and may have harmful cardiovascular health effects, such as atherosclerosis (partially blocked arteries), heart attack, and stroke.

In addition to public health, we have to consider Mother Nature’s health. Although cannabis is restricted somewhat under the Clean Indoor Air Act, think about our community’s natural treasures not covered. Places like parks, walking trails, and other outdoor spaces. They need protection too.

For more information on ways you can help protect your community from exposure to secondhand smoke from both tobacco and cannabis, email Ken Dahlgren of Tobacco Free Chautauqua, Cattaraugus, Allegany (TF-CCA) at kenneth.dahlgren@roswellpark.org.

Jonathan Chaffee is Reality Check coordinator for Tobacco-Free Chautauqua, Cattaraugus and Allegany.