For every crop in the United States, the Environmental Protection Agency carries out a rigorous set of tests to determine which pesticides are safest. How and when a pesticide is used can depend on how that crop is consumed by the average person — is it ingested, inhaled or applied topically?
It’s a precise science that aims to keep consumers safe from potentially toxic residues. But, like most federal regulations, none of it applies to the marijuana industry.
In lieu of government research, a state with legal marijuana, like Colorado, is left to develop its own set of rules. That can leave cannabis growers largely on their own.
Whitney Cranshaw, an entomologist at Colorado State…