Cannabis has been shown to contain molds, fungi, and bacteria. Studies focused on grow houses seized by drug enforcement agencies have found elevated mold counts during the removal of marijuana plants. Molds have been detected in police drug vaults containing confiscated marijuana. Various bacteria have been linked to marijuana samples, which are likely infected post-harvest during drying and storage. One study found that 13 out of 14 cannabis samples were infected with fungus.
Are contaminants harmful? For individuals with compromised immune systems, contaminated cannabis may be dangerous. A study of cannabis users showed that one individual with a genetic immune system malfunction was less able to fight off fungi associated with cannabis than individuals with typical immune function. Cancer patients may also be more susceptible to the fungus in cannabis because of their weakened immune systems. In fact, cancer patients using cannabis may develop fungal sinus infections. However, a 20 year study of healthy individuals found that occasional marijuana use, less than 3 times per month, does not negatively affect the pulmonary system.
Contaminants are likely present in cannabis. The conditions necessary to grow marijuana plants promote the growth of molds and bacteria. Of course you can always cultivate marijuana yourself. However, the danger associated with cannabis use varies among individuals based on their health status. Individuals with compromised immune systems may be more susceptible to contaminants. Healthy individuals with limited cannabis use may possess a natural immunity against the molds, fungi, and bacteria in cannabis. Therefore, the potential threat of cannabis contaminants depends on an individual’s health.