A new study discovered that marijuana users had statistically greater amounts of lead and cadmium in their blood and urine than non-users.

Author Tiffany Sanchez, an assistant professor of environmental health sciences at Columbia University Mailman School of Public Health in New York City, said that Marijuana users had 27% higher levels of iron in their blood and 21% higher levels in their urine compared to non-users.

PHOTO | COURTESY a person smoking weed

According to the US Environmental Protection Agency, there is no safe level of lead in the body.

 According to Sanchez, Marijuana users also had 22% higher cadmium levels in their blood and 18% higher amounts in their urine than non-users.

Did you read this?

  1. Number Of Kenyans Consuming Bhang Increases By 90%
  2. 'Mathe Wa Ngara' 54-Year-Old Drug Queen Arrested In Ngara
  3. Moyale Residents Warned To Stop Feeding Weed To Donkeys

She added that cadmium and lead stay in the user's body for quite a long time.

"Cadmium is absorbed in the kidney and filtered out through the kidney." So, when you look at urinary cadmium, it represents total body load, or how much you've consumed over a lengthy period of chronic exposure."

PHOTO | COURTESY weed plant

According to the EPA, cadmium has been related to renal illness and lung cancer in humans, as well as fetal abnormalities in animals, and sets specified limits for cadmium in air, water, and food.

Heavy metals are naturally present in the soil in which crops are grown and cannot be avoided, which is why they can be found in the air, water, and food supply.

However, some crop fields and localities have higher harmful levels than others due to the overuse of metal-containing herbicides and persistent industrial contamination.


Not all plants can tolerate high levels of confinement without being harmed. Cannabis, on the other hand, has a unique property: it is a "known hyperaccumulator," which means it absorbs heavy metals, pesticides, petroleum solvents, crude oil, and other potentially dangerous compounds without harming itself.

A 2022 study looked at heavy metal rules in the 31 states and the District of Columbia where recreational cannabis is legal and discovered that 28 had arsenic, cadmium, lead, and mercury regulations.