Pseudomonas aeruginosa

Pseudomonas aeruginosa

Pseudomonas aeruginosa is a gram-negative, rod-shaped bacterium that has been identified in humans and plants. P. aeruginosa is commonly found in moist locations, such as soil and water, which happen to be the two most common growth media for cannabis. As a result, P. aeruginosa has been identified on cannabis samples.

Why is Pseudomonas aeruginosa dangerous to cannabis users?


P. aeruginosa it is an opportunistic pathogen that can infect the respiratory system of patients with weakened immune defenses. The bacterium has a tendency to persist in bronchiectatic airways, due to its ability to produce virulence factors and modulate immune defenses by quorum signaling and biofilm production.


P. aeruginosa is one of the most common bacterial pathogens found in patients with bronchiectasis, a respiratory condition that causes damage to the bronchi and bronchioles and leaves patients susceptible to bacteria infections.


P. aeruginosa is also a frequent cause of ventilator-associated pneumonia. Pseudomonas bronchitis is common late in the course of cystic fibrosis. Isolates from patients with cystic fibrosis have a characteristic mucoid colonial morphology and result in a worse prognosis than nonmucoid Pseudomonas.


A study published in 2017 describes a case where a patient developed a “cataclysmic pulmonary infection” from smoking cannabis with a bong contaminated with P. aeruginosa. It’s unclear whether the cannabis contaminated the device, but the case still shows cannabis users can acquire a life-threatening P. aeruginosa infection from use of contaminated instruments or devices.