Pesticides, solvents and harmful bacteria have all been found lurking in marijuana products in California.
Testing companies licensed by the state have found a small number of E. coli and salmonella cases.
Researchers say nearly 20 percent of marijuana products have failed potency and purity tests.
Everything from cannabis-infused cookies to candies and extracts are tested.
Critics blame the failed tests on unrealistic safety standards.
Failed safety tests raise red flags about marijuana grown in California