Health Canada will begin randomly testing pot from licensed medical marijuana producers to ensure that unauthorized pesticides are not used in the growing process, after two growers were found to be using banned pesticides, the agency announced Wednesday.

The random inspections will check to ensure that licensed producers are sticking to the list of 13 approved pesticides for use on medical marijuana. The agency says producers caught using unauthorized pesticides will be required to recall their products, and corrective action will be taken.

The new measures come after products from two licensed growers were found to contain low levels of myclobutanil, bifenazate and pyrethrins, which are prohibited under the Pest Control Products Act and the Access to Cannabis for Medical Purposes Regulations. Corrective action was taken in both cases and Health Canada says it’s “satisfied” with the voluntary recalls carried out by the producers

The affected producers were based in Moncton, N.B., and Toronto.

Myclobutanil is prohibited from use on combustible plants like marijuana and tobacco, because it emits hydrogen cyanide when burned. Colorado, Oregon and Washington have issued similar bans. However, the fungicide is still allowed on certain crops that are not burned when consumed.

Bifenazate is approved in Canada for use on apples, grapes and greenhouse vegetables only.

Pyrethins are only permitted for use in pesticide mixes on organic food.

“The Department will be providing additional compliance education and information to licensed producers,” Health Canada said in a statement on Wednesday.

Health Canada already conducts random unannounced inspections at facilities belonging to the 38 licensed producers across the country.

The agency says it is committed to “continuously improving on safety practices even though existing programs demonstrate effectiveness in identifying issues of non-compliance.”