‘Things have to be clean’: Local weed business reacts to marijuana contamination warning

MEDWAY, Mass. — It is one of the state’s most tightly regulated industries — and doesn’t Marc Rosenfeld know it.

“We have to account for every bit of plant, every bit of flower, every bit of waste,” said the Co-Founder of CommCan, a family-owned cannabis cultivation facility in Medway. “Every leaf that comes off the plant has to be weighed, even if it has no active cannabinoids. It has to be ground up with dirt before it’s thrown away.”

And every batch of cannabis destined for retail sale has to undergo pre-market testing for contaminants. Early last year, twelve different products containing four different strains of cannabis did undergo testing — and passed. But this week, the Cannabis Control Commission reported that these products, sold over a period of nine months and in more than 30 dispensaries, failed subsequent testing.

Just like all humans, all plants are subject to disease. And that would include Cannabis Sativa, foundation of the state’s $1.6 billion marijuana industry, and, as it turns out, a rather challenging species to cultivate successfully.

“We have to grow cannabis in a clean environment, and we have to control things like humidity and things that get introduced into the cultivation system,” said Kimberly Gwinn, PhD, a professor of plant pathology at the University of Tennessee.

Cannabis needs the right conditions because it’s subject to infection by mold. And that is what the CCC’s follow-up testing found in those twelve previously passed products. The agency issued a health advisory urging consumers to destroy or return to site of purchase any of the involved products listed on its website.

None of CommCan’s products are part of the advisory. James Sipe, director of cultivation for the company, said that’s no accident.

“Things have to be clean,” he said. “And airflow is completely important to prevent fungal growth.” Sipe said one way to enhance the latter is to limit the number of cannabis plants per grow room.

And Gwinn said the precautions against mold don’t stop once cannabis is harvested.

“In the cannabis head, this is a very moist environment,” she said. “Drying properly is very important in  producing high quality cannabis.”

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