[earth.com] Marijuana smokers have significantly higher levels of toxic metals in their blood and urine compared to non-marijuana tobacco users, according to a recent study from Columbia University’s Mailman School of Public Health.The research, led by Professor Tiffany Sanchez, indicates that marijuana may be an under-recognized source of metal exposure, as it remains illegal at the federal level and therefore unregulated by government agencies.
The study authors say the issue has never been more important as marijuana use in the skyrockets in the United States, with an estimated 42 million regular users.
LEAD AND CADMIUM LEVELS
The researchers compared participants who exclusively used marijuana with non-marijuana tobacco users and found that those who used marijuana had significantly higher lead levels.
Specifically, marijuana smokers users had 27 percent higher levels of lead in their blood and 21 percent higher levels in their urine.
In addition, cannabis users had 22 percent higher cadmium levels in their blood and 18 percent higher levels in their urine compared to non-users.
TOTAL BODY BURDEN
Professor Sanchez and her team predicted that because cannabis is known to accumulate metals, marijuana smokers would have higher metal biomarker levels than those who did not use it.
The study confirmed this prediction, establishing marijuana as a source of cadmium and lead exposure.
"Both cadmium and lead stay in your body for quite a long time," said Professor Sanchez. "Cadmium is absorbed in the renal system and is filtered out to through the kidney. So, when you’re looking at urinary cadmium, that’s a reflection of total body burden, how much you have taken in over a long period of chronic exposure."