Australia’s Testing Protocols for Medical Cannabis

Alternaleaf Team
Written by
Alternaleaf Team
Mar 4, 2023
Last updated:
Nov 16, 2023

Medical cannabis testing is rigorous, as it is for all medicines in Australia. In fact, medical cannabis is typically tested more rigorously than other supplements, like vitamins.

As only one example, medical cannabis producers must prove that their medical cannabis products are free from harmful bacteria, toxins, and other substances. It also has to be free from heavy metals and synthetic additives.

But many still have concerns about cannabis because it’s only recently transitioned into the legal, medical arena. Even if it’s controlled by the Therapeutic Goods Agency (TGA) and prescribed by a doctor, is marijuana safe? What cannabis testing occurs to ensure your patient safety?

How Is Medical Marijuana Regulated in Australia?

Prescription medical cannabis in Australia is tightly controlled by the TGA, which regulates all medicines in Australia. Their job is to ensure medicines are safe for human consumption and have strict rules and testing protocols.

All medical cannabis producers in Australia must follow the TGA rules and any foreign producers must also meet equivalent standards. Not only do manufactured medical cannabis products (like oils, vape cartridges and topicals) meet these high standards but so must any cannabis plant or other ingredient used to create the product.

What Cannabis Testing Is Required Under Australian Law?  

Cannabis producers in Australia are expected to test every batch of medical cannabis they produce. There are a few careful exceptions to this rule, but typically manufacturers test all their batches and provide a detailed certificate of the test results.

So what is cannabis testing looking for?

two petri dishes, leaves, green background

Every batch of cannabis produced for patients is tested for heavy metals, pesticides, and more

Cannabinoid Content

Firstly, the THC and CBD content of each batch must be confirmed. In Australia, medical cannabis products are divided into five categories based on their CBD and THC content on a sliding scale. Category 1 products contain at least 98 percent CBD, while Category 5 products contain at least 98 percent THC.

The TGA ensures that every medical cannabis product contains the right amount of cannabinoids and that no other active ingredients are present. For products like flower, oils, and extracts, producers must also label them with the plant species and which part of the plant was used.

Bacteria and Microbes

Because medical cannabis products are made from plants, it’s crucial to ensure they aren’t contaminated with bacteria or fungi. This is a natural risk for all crops and can happen during cultivation, harvesting, or processing. For example, mould could form on cannabis plants stored in damp environments.

The TGA lays out strict limitations to the presence of bacteria, fungi, and other microbes in a sample. Cannabis is tested for the total amount of bacteria, fungi, yeast and specific bacteria such as E. coli and Salmonella. Any batch that contains too many of these contaminants will be rejected.

Heavy Metals

Another concern is heavy metal pollution. Heavy metals like lead, arsenic, and mercury can be toxic and carcinogenic for humans, especially in high quantities. Suppose the soil used to grow cannabis is contaminated with heavy metals. In that case, there is evidence that cannabis plants can easily absorb those heavy metals during their development.

The TGA requires all producers to carry out specific tests for heavy metals, with safe limits for each potential pollutant, e.g. 5.0mg/kg of lead and 0.5 mg/kg of mercury. Growers may also avoid heavy metal pollution by adapting how they farm and ensuring soil on cannabis farms does not contain heavy metals.


Pesticides can be helpful for medical cannabis growers to protect their plants and grow high-quality cannabis. Like with all agriculture in Australia, only certain pesticides can be used and only at certain times, and many growers choose not to use pesticides at all.

But, if pesticides are used, samples of medical cannabis are tested to make sure there are not any lingering pesticides left in the final product. Producers test for dozens of pesticides against international safety standards.

Safe Processing & Additives

Finally, medical cannabis is processed after harvesting, which must be done safely. Decontamination is a standard process to remove bacteria and fungi from the plant. Specific sterilisation methods, like using a gas called ethylene oxide, are banned, while sterilisation using safe levels of radiation, on the other hand, is allowed if producers ensure it doesn’t damage the product.

Producers must also prove they haven’t added any banned additives to their medical cannabis sample. They are not allowed to add tobacco or synthetic cannabinoids, and any active ingredient must come directly from the cannabis plant.

Medical Cannabis Adheres to Strict Quality and Safety Controls

Australia has a robust system for medical cannabis testing, and every medical cannabis product available to patients is free from contamination, heavy metals, and dangerous additives. Because they are prescription products, patients can be confident they’re receiving a safe, high-quality product that contains precisely what it says on the label.

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