Cannabis Cultivators Suffer from Fatal Fungal Diseases Linked to Bat Droppings Fertilizer
Avid enthusiasts of homegrown cannabis, beware: certain fertilizers ought to be avoided, particularly bat guano, or bat excrement. Medical professionals are urging caution around this substance following two cannabis cultivators contracting a lethal fungal infection linked to its usage.
Experts from the University of Rochester detailed these peculiar infections in a recent case study. Both incidents involved local men suffering from a severe case of histoplasmosis, likely resulting from inhaling spores of the Histoplasma fungus from bat guano they had used or planned to use as fertilizer for their marijuana plants. Although exposure to bat guano isn't a common risk for many individuals, the researchers highlight that it has gained popularity as an "organic superfood" for cannabis cultivation through online promotion.
Histoplasmosis begins as a lung infection caused by breathing in the spores of the Histoplasma fungus, such as the species Histoplasma capsulatum. Typically, exposure to bat guano does not cause illness; however, it can lead to relatively mild pneumonia, resulting in symptoms like fever, cough, chest pain, and body aches. Rarely, the infection can become chronic and affect other body parts, like the brain, leading to life-threatening complications. People with weakened immune systems are more susceptible to severe or chronic histoplasmosis.
These infections are not contagious and can only be contracted from environmental sources of the fungus. The fungus is primarily found in the central and eastern United States, living in soil. However, Histoplasma fungi grow well in soil saturated with bird or bat droppings, and these fungi are naturally found in bats. As such, bats play an essential role in the transmission of histoplasmosis. Outbreaks of histoplasmosis are often triggered by disturbing contaminated soil, which releases spores into the air. However, the recent cases suggest that bat guano itself may act as a deadly carrier of histoplasmosis.
The first victim, a 59-year-old man, had purchased bat guano online and used it to fertilize his marijuana crops. The second victim, a 64-year-old man, had discovered a "heavy bat infestation" in his attic and intended to use the bat guano as fertilizer for his plants. By the time the men visited doctors, their conditions had significantly worsened, leading to secondary infections, sepsis, and eventual death from infection complications. Both men had pre-existing health issues, such as emphysema or past heart surgery, that may have contributed to their susceptibility to severe illness.
"Exposure to bat guano among cannabis growers appears to be a recent trend that can result in histoplasmosis cases and outbreaks," the researchers noted in their paper, published in the journal Open Forum Infectious Diseases.
Histoplasmosis is a relatively rare diagnosis (approximately 3,000 to 7,000 cases are reported annually in the United States, according to the Centers for Disease Control and Prevention). However, the researchers believe that cannabis growers are largely unaware of the potential risks associated with bat guano. They point out that guano is often promoted online as a "natural superfood" for growing marijuana because of its high nitrogen and other compound content. Nevertheless, neither federal nor local agencies seem to be testing commercially purchased guano for the fungus. As marijuana cultivation becomes increasingly popular with legalization efforts, the researchers propose increasing educational efforts to address this exposure risk and keeping fungus-tainted guano fertilizer away from consumers.
"It is essential to raise awareness among physicians and patients to reinforce personal preventive measures and establish timely diagnoses. Commercial biofertilizers containing bat guano should be tested for Histoplasma capsulatum before reaching the market," the researchers wrote. "If testing is not feasible, risk mitigation strategies should be implemented."
In the future, it would be beneficial for regulatory bodies to conduct tests on commercially sold bat guano to ensure it's free of the Histoplasma fungus, protecting the health of cannabis growers. As technology advances, innovative and safer alternatives to bat guano as organic cannabis fertilizers should be explored in the field of agricultural science.
