Marijuana Users Have Higher Metal Levels in Blood, Urine

FRIDAY, Sept. 1, 2023 (HealthDay News) -- Marijuana may be a source of cadmium and lead exposure, according to a study published online Aug. 30 in Environmental Health Perspectives.

Katlyn E. McGraw, from Columbia University in New York, and colleagues examined whether individuals who use marijuana have higher metal biomarker levels versus those who do not use marijuana. The analysis included data from 7,254 participants in the National Health and Nutrition Examination Survey (2005 to 2018). Researchers looked at five metals in blood and 16 metals in urine.

The researchers found that those reporting exclusive marijuana use had significantly higher mean cadmium levels in both blood (1.22 μg/L; P < 0.001) and urine (1.18 μg/g; P = 0.004). Additionally, exclusive marijuana use was associated with significantly higher mean lead levels in both blood (1.27 μg/dL; P = 0.006) and urine (1.21 μg/g; P = 0.058).

"Taken together, these observations suggest that marijuana use is an important and underrecognized source of Cd (cadmium) and Pb (lead) exposure independent of tobacco use and that chronic marijuana use may contribute to adverse health effects associated with chronic, low-level metal exposure," the authors write.

Abstract/Full Text