At Keystone State Testing we do a very robust array of contaminant testing but for simplicity let's look at a very common contaminant, such as microbial contaminants, which are a very frequent contaminant amongst produce being grown in the United States.
We follow the same testing methods that the FDA uses for food like strawberries, as an example. Only the growers have to do extra steps to make sure that unlike strawberries, the cannabis flower won't develop mold after sitting around for two weeks! The growers have to make their flower have a dryness of approximately 10%. Mold likes to grow in humid areas (like a shower). So if you had a cannabis flower you bought in Colorado and left it in a shower for a couple weeks it would probably develop mold. That is why flower is sold in pill bottle type containers so they stay dry.
The growers are also required to test the flower to make sure it is safe before they sell or process it. The tests the flower go through include: determining what cannabinoids (THC, CBD and others) are present and their concentrations, what terpenes (pine, lemon, etc) are present and their concentrations, and any contaminant. Contaminant testing includes testing for pesticides, mycotoxins (this is a byproduct of a certain bacteria that is rarely seen in MMJ but is tested for in grain products so the state is being extra cautious), lead, mercury, cadmium, and arsenic, E-coli, salmonella, bile-tolerant gram negative bacteria (a specific type of bacteria that can cause digestive issues), total bacteria counts, and total yeast and mold counts. The flower must have less than specific amounts set by the Department of Health, the same way produce does.
After passing these tests, the flower may then be sold or processed. In processing the cannabinoids and terpenes are separated from the flower so they can either package them directly in a wax form, or add them to a pill or lotion or tincture (a liquid that can be added to food or drink) or a vape cartridge.
Before any processed material goes to market the state requires the lab to test again for all the same tests the flower went through and making sure no liquids used in extraction remain in the final product. These tests ensure that any packaging used is safe and won't make a patient sick.
The state has required we complete a very thorough application process demonstrating how we test to ensure the cannabis is safe for consumption at every step of the process. We were not allowed to begin testing until we received accreditation (this means approval from a very reputable third party company). Additionally, we were required to complete proficiency tests. This means we receive a sample that has one or several contaminants at known levels by others and we had to find and identify them as well. This reassures everyone that we are capable of doing the tests necessary for public safety.
We at Keystone State Testing are in the business of ensuring products are safe. We do not test for industrial hemp, which is used in the production of CBD only products acquired online or produced by non-MMJ producers. Industrial hemp and CBD products are NOT required to complete the same safety testing as MMJ, so they can use moldy plants, or they could have been sprayed with pesticides or contain high levels of heavy metal, or used poor extraction solvents that remain in the product. Therefore, those products can be sold while containing dangerous contaminants.
First, we can't verify all products on the market are safe and accurate.
We at Keystone State Testing do not test for all companies within Pennsylvania. However, we can verify that any company that tests with us, has safe and accurate products for patients.
It is necessary to follow the recommended instructions that any product comes with. Just as you wouldn't want to eat a strawberry that's been left in a hot car for several weeks, some products recommend cold storage, or shaking before use. Reading the label carefully will ensure optimal safety of the product.
If a label does not contain storage instructions, best practices include storage in a cool, dark place.