New research finds people who use marijuana may show increased levels of lead and cadmium. Lead and cadmium are two heavy metals known for their potential to cause health issues over time.
The study used more than 7,200 adults, with 358 of them reporting marijuana use in the past month. Among this group, their blood lead levels were found to be 27% higher compared to those who didn’t use marijuana or tobacco.
Similarly, their blood cadmium levels were 22% higher. The study, published in the journal Environmental Health Perspectives, also revealed similar trends in urine samples.
Blood & Urinary Metal Levels Among Exclusive #Marijuana Usershttps://t.co/xuHyJFGC9q@_atanas_ @_INPST @ScienceCommuni2 @DHPSP @ScienceCommuni2 @DHPSP @BenBikmanPhD @Mangan150 @ralzahrani2020 @nootropicguy @BowTiedUM @ResilientDad @DrPalmquist @drsanjaygupta @hubermanlab pic.twitter.com/mpWPPMtcep— J P Fanton (@HealthyFellow) August 31, 2023
The researchers, a team from Columbia University, were aware beforehand that cannabis plants can absorb heavy metals from the soil. The metals then travel from the plant’s stalk into its leaves and flowers. This study adds to the understanding that these heavy metals can also find their way into the human body.
Lead exposure, even at low levels, can hinder brain development in children and result in learning and behavioral problems. In adults, chronic lead exposure link with hypertension, heart issues, and kidney damage.
Cadmium is classified as a human carcinogen by the World Health Organization and can lead to kidney disease and fragile bones. Cadmium can harm even at low exposure levels like from tobacco smoke.
Tiffany Sanchez, an author of the study and an assistant professor of environmental health sciences at Columbia’s Mailman School of Public Health, shows that both cadmium and lead can persist in the body for years after exposure ends.
The research team analyzed data collected between 2005 and 2018 as part of the National Health and Nutrition Examination Survey. This data didn’t differentiate between various methods of marijuana consumption, like edibles or joints. However, inhaling lead consider more concerning than consuming it through food.
Sanchez noted that while tobacco is a primary source of cadmium exposure in the general population.
The marijuana industry lacks standardized regulations for contaminants like heavy metals due to varying marijuana laws across states. Marijuana is illegal at the federal level. But legal for recreational use in some states and for medicinal use in others. Sanchez’s study underscores the inconsistency of regulations regarding contaminants even in legal marijuana products.
To ensure a marijuana product is free from heavy metals, Seaberg suggested purchasing from legal dispensaries. State health department websites typically have lists of authorized dispensaries.