The aerobic plate count indicates how much bacteria is on a given sample. This cannabis microbial test is a valuable tool in estimating product quality. While the test is fairly generic and does not differentiate types of bacteria, large numbers of microorganisms can indicate unsanitary conditions.

Yeasts and molds are common microbial adulterants that can cause deterioration and spoilage in cannabis. These contaminants thrive in moist environments and often produce toxic compounds called mycotoxins. When present in copious amounts, mycotoxins can be hazardous to human health (especially those who are immunocompromised) and cannot be destroyed through heating. The discovery of high levels of yeast and mold colonies can mean fungal spoilage, indicating such products should not be smoked/consumed.

When determining the bacterial safety of a product, testing for coliforms is a standard practice due to the difficulties of screening for each individual pathogen. Prevalent in the feces of warm-blooded animals, coliforms are not pathogenic themselves and rarely cause illness; however, they are strong indicators that other pathogenic organisms of fecal origin are present. The most common of these potential pathogens include Enterobacter, Fecal Coliform, and Escherichia Coli (commonly known as “E. Coli”).