TYM Tests for Cannabis, Total Yeast and Mold Contamination

The results of a Total Yeast and Mold (TYM) test are an indication of yeast and mold contamination on a cannabis sample.

Yeasts and molds can cause deterioration and decomposition of foods, which is why food manufacturers will commonly test their products for TYM. Certain species of yeast and mold, such as Aspergillus fumigatus, produce toxins that can cause potentially fatal infections.

However, TYM tests are unable to differentiate between pathogenic, beneficial, and benign yeast and molds, making them poor indicators of safety. A low TYM result does not mean a cannabis sample is free of pathogens. A high TYM result doesn’t mean a sample is harmful to consumers. This is especially true in cannabis, which has a diverse microbiome of beneficial microbes that are not harmful to humans. For example, many organic cannabis growers use Trichodermaa fungus that can help plant nutrition and protect it from disease.

Still, many cannabis regulators require cannabis samples pass TYM testing before they can be sold in dispensaries. The most current version of the Cannabis Inflorescence and Leaf monograph published by the American Herbal Pharmacopoeia, which many states use to determine pass or fail criteria for microbial testing, recommends less than 10,000 CFU/g on cannabis plant material and 1,000 CFU/g on extracts.

Who requires TYM testing?

  • Canada
  • Colorado
  • Connecticut
  • Florida
  • Hawaii
  • Illinois
  • Iowa
  • Maine
  • Maryland
  • Massachusetts
  • Michigan
  • Minnesota
  • Montana
  • Nevada*
  • New Hampshire
  • New Mexico
  • North Dakota
  • Ohio
  • Oklahoma
  • Pennsylvania
  • Rhode Island
  • Utah
*Only required for select matrices, view our Cannabis Microbial Testing Regulations by State page for more information

Why Use qPCR for TYM testing on Cannabis?

Peer-reviewed studies have shown that qPCR testing methods, such as the PathoSEEK Microbial Safety Testing Platform, are able to more accurately detect and quantify yeast and mold species present on a cannabis sample than culture-based methods. The PathoSEEK Total Yeast and Mold test looks for a specific DNA sequence that exists in all yeasts and molds. Because of this, the PathoSEEK Total Yeast and Mold test can detect all yeast and mold species, regardless of whether they grow in culture. Culture-based tests can only detect the species that grow in a given medium and timeframe. Conversely, qPCR can more effectively exclude off-target microbial species, such as bacteria, which have been shown to grow in TYM culture medium.

The PathoSEEK® Total Yeast & Mold Detection Assay is used in combination with SenSATIVAx® DNA Purification Kits, Grim Reefer Free DNA Removal Kit, TLP Extraction Enzyme, and qPCR Master Kit v3 to detect yeast and mold organisms in cannabis samples.

This method received AOAC Performance Tested MethodsSM (PTM) certification for the detection and enumeration of total yeast and mold in dried cannabis flower.

Test for Total Yeast and Mold with PathoSEEK

Labs can use our PathoSEEK Microbial Safety Testing Platform to test for Total Yeast and Mold in a variety of cannabis matrices. The PathoSEEK® Platform is the only method designed for and validated on cannabis flower, extracts, and a variety of infused products.

Start Testing with PathoSEEK

Available Total Yeast & Mold Products

ITEM #NAMEREACTIONS 
420103PathoSEEK® Total Yeast & Mold Detection Assay200Buy Now
420303PathoSEEK® Total Yeast & Mold Positive Control50Buy Now

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