People who smoked only marijuana had higher levels of blood and urine than more smoke-related toxins such as naphthalene, acrylamide and acrylonitrile than non-smokers, according to the study published Monday in the journal EClinicalMedicine.
“Marijuana use is on the rise in the United States, with an increasing number of states legalizing it for medical and non-medical purposes – including five additional states in the 2020 elections,” said lead author Dr. Dana Gabuzda, lead investigator in Cancer Immunology and Virology at the Dana-Farber Cancer Institute in Boston, in a statement.
“The increase has raised concerns about the potential health effects of marijuana smoke, which are known to contain some of the same toxic combustion products found in tobacco smoke,” Gabuzda said.
Tobacco smokers
The new research presented data from three studies on 245 HIV-positive and HIV-negative participants. The researchers said they chose to study people with HIV infection because of the high prevalence of tobacco and marijuana smoking, which is usually found in this population.
Medical records were compared with blood and urine samples of various chemicals produced by the breakdown of nicotine or by the burning of tobacco or marijuana.
However, marijuana smokers did not have higher levels of acrolein in their bodies.
“This is the first study that compares exposure to acrolein and other harmful chemicals related to smoking over time to exclusive marijuana smokers and tobacco smokers and to see if those exposures are related to cardiovascular disease,” Gabuzda said.
Acrolein is a chemical with a burning, sweet, pungent odor created by burning fuels such as gasoline or oil and organic matter such as tobacco. The chemical is not added to cigarettes; acrolein is produced by burning the sugars present in tobacco when smoked.
Weed smokers
While weed smokers had higher amounts of naphthalene, acrylamide and acrylonitrile in their blood and urine than non-smokers, even higher levels were found in people who smoked tobacco or a combination of marijuana and tobacco.
Acrylamide is a chemical used in the manufacture of paper, plastics and dyes, but it is also produced when vegetables such as potatoes are heated to high temperatures. It is also a component of tobacco smoke.
The EPA classifies acrylonitrile as a “probable human carcinogen.”