Robert Grandt works in the grow room at 3D Cannabis Center in Denver on March 11, 2015. (RJ Sangosti, Denver Post file)

Tighter regs proposed for pesticides used on Colorado pot

State regulators have proposed rules that would further restrict which pesticides can be used to grow marijuana to those that are least harmful and already are allowed on crops intended for human consumption and tobacco.

The draft rules mark the state’s latest effort in a process that began about two years ago but has dragged on amid industry pressure and lack of guidance from the U.S. Environmental Protection Agency.

Currently, the state allows more than 200 pesticides on marijuana, but the new rules would pare it to about 75, officials say, although more can be added.

The proposal would limit allowable pesticides to those so nontoxic they do not need to be registered with the federal government or those so safe to use that no residue level needs to be determined.

The rules were proposed last week, and marijuana industry representatives said Monday they are reviewing them.

“The licensed marijuana industry and the state of Colorado are all stuck in the same dilemma in that pesticide regulations are controlled by federal law, and the federal government refuses to provide guidance,” said Michael Elliott, executive director of the Marijuana Industry Group.

But one business owner said the new rule would cause problems. The proposal would “take away half of the products I use now,” said Rob Jany, chief cultivation officer at Tru Cannabis in Denver, “and I face losing my crop no matter what I use.

“This will be a problem for the next 10 years until the EPA wakes up and properly tests everything,” Jany said. “We’re all trying to wiggle our way around this so as not to get into trouble.”

No date has been set for public hearings, but the state Department of Agriculture has said it could be as early as December or January.

If passed, the suggested rules would be a marked change in how the state has treated pesticides on cannabis for the past two years, which has been to allow those whose warning labels are so broadly written it would not be a violation to use them. That included a number of pesticides with tolerance limits established for certain food crops but whose safety on marijuana was unknown.

Under the new rules, which also would apply to hemp growers, only those pesticides exempt from any tolerance limits could be used, and they must be allowed on crops intended for human consumption by the EPA.

The federal agency sets tolerance levels, the maximum amount of a pesticide that can remain in or on foods. In some cases, a pesticide is deemed safe enough for a specific application that it is exempt from the tolerance rule.

The pesticide also would have to be allowed for use in specific locations such as commercial greenhouses or crop fields, according to the proposed rule.

Federal law prevents any pesticide from being used outside of label restrictions. Marijuana is illegal under federal law, and no pesticide is specifically allowed on the plant.

Part of the rule would allow for pesticide manufacturers to obtain special exemptions from the EPA to allow their products specifically on marijuana, a long and expensive process known as 24c for the federal code that regulates it. An exemption is typically given when a state can show a crop is endangered by a specific pest that cannot be treated by any other means.

The exemptions would require a company to test its product on marijuana and offer the data as proof it is safe for use and at what level residues can be found.

The process is further complicated because federal law distinguishes pot as a drug, not a food product, and pesticide levels are different for each. Also, because marijuana is sometimes ingested by children with medical needs, the allowable levels of pesticide residues are restricted even further.

An EPA spokeswoman said no company has yet requested the exemption, and it is unclear whether the agency will give a company one because the crop is illegal under federal law.

The issue of pesticides on pot has been contentious since at least 2012, when state inspectors first noticed marijuana grow operations were using them.

With no federal guidance on how to regulate them and an industry reluctant to accept limitations on what could be used, state officials waffled over what to do and made pesticide enforcement a low priority, The Denver Post found in a review of state documents and records.

David Migoya: 303-954-1506, or @davidmigoya

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