By Shawn Kassner, senior scientist, Neptune and Company, Inc.

Over the past few years, we have seen many states legalize medical and recreational cannabis. Legalization of medical cannabis, in particular, has generated increased awareness of the many health issues that cannabis and cannabis-based products are used to treat. Pediatric seizure disorders, post-traumatic stress syndrome, abatement of chemotherapy side effects and pain management for cancer patients are just a few of the many conditions which patients may choose to treat with medical cannabis.

As awareness and use of cannabis-based products has increased, legalization has allowed public health agencies and members of the public to question the quality, purity and potency of these products. In response, states have instituted requirements for testing cannabis-based products to varying degrees. But people are asking, “Why should we have to test cannabis products?”

Cannabis has long been considered a natural product with few health hazards. In reality, the production of cannabis and associated products may include the use of pesticides, solvents and the risk of microbial contamination. For individuals whose health is compromised in some way (patients undergoing chemotherapy, for example), these hazards may pose significant health risks.

The most immediate potential health risks of cannabis products are bacteria, mold and fungus present at levels that can cause microbial infections. Although bacteria live everywhere including within us, pathogens like Salmonella and E.coli, can quickly infect a healthy person. These bacteria have a much higher potential for affecting a person whose immune system is compromised. Microbial testing ensures that the product they are purchasing cannot cause an infection that would worsen their health.

Many cannabis growers, like other types of farmers, use pesticides to control microbial, insect and fungus infestations at their facilities. Because the US Drug Enforcement Agency (DEA) classifies cannabis as a schedule 1 controlled substance, the Environmental Protection Agency (EPA) and the Food and Drug Administration (FDA) cannot issue guidance on the use of pesticides on cannabis plants. However, state public health and agricultural agencies in jurisdictions where cannabis is legal have begun to regulate the type and amount of pesticides that can be applied to cannabis.

For medical cannabis patients, the fewer chemicals used, the better. Pesticide risk potential has yet to be fully understood because little scientific research has been performed. Thus, keeping the use of pesticides to a minimum and ensuring that approved pesticides are used – which requires analytical testing – is an essential part of any regulated program.

Another issue is potency. All cannabis plants and products aren’t the same, which means that potency varies widely. Without knowing the potency of the products, a person may unwittingly take too much or too little. Prescription and over-the-counter medications have dosage information on the label so patients know how much to take. This is a mandatory practice for medicinal products. Testing for potency and adding this information to the cannabis product label gives patients vital information on what they are purchasing and how much of a product they should consume or use. Without this, they are flying blind in the treatment of their illness or condition. Further, many states require that cannabis products contain a maximum amount of cannabinoids and this must be verified with testing. Whatever the state requirements, it is imperative that patients know the level of active ingredients in cannabis products and can count on their homogeneity.

These concerns aren’t limited to consumption of the plant. Patients using cannabis extracts and oils need to be aware that the active ingredients (cannabinoids and terpenes) are extracted utilizing a variety of techniques including the use of solvents such as propane, butane, acetone and alcohol. Exposure to solvents can cause a variety of illnesses that can negatively impact a patient. Though many states have set rigorous requirements for acceptable levels of residual solvents, cannabis products need to be tested to ensure that they are at a safe concentration. As more products are tested for solvents, many grow facilities and manufacturers have begun to develop alternative extraction techniques that do not use solvents, thus avoiding this issue entirely.

More patient and industry advocacy groups are demanding testing as awareness of potential hazards grows. To ensure their products have been tested, patients should ask dispensaries and manufacturers for detailed testing information that may not be included on product labels. This will help to intensify the push for safer and more effective cannabis-based products for the treatment of their illness or condition.

Both public health agencies and the cannabis industry want competent accredited laboratories to perform the testing with standardized methodologies.

The cannabis industry is responding with new and improved growing and extraction techniques and greater involvement in the regulatory process, and public health agencies are responding with new testing requirements, product recalls and by taking a consensus approach to regulation involving all cannabis industry stakeholder groups including consumer advocates.

Learn more:
“A Clearheaded Case for Cannabis Testing.” Lab Matters, Winter 2016
“Guidance for State Medical Cannabis Testing Programs.” APHL, May 2016

This post wasn’t written by an APHL staff member and the views expressed in the post are those of the guest author and do not necessarily reflect the views or opinions of APHL. If the post contains an evaluation or opinion about a product or service, this represents the guest blogger’s personal belief and does not represent APHL’s endorsement or critique.