A medical-marijuana group says it’s planning a rally outside a Hallowell dispensary, protesting pesticide use on plants and its operator’s treatment of workers.

Chris Kenoyer of the Maine Patients Coalition said in a news release that a rally will take place outside the downtown dispensary at 4 p.m. on Friday.

The rally was scheduled in response to a recent state inspection of an Auburn growing operation owned by Wellness Connection of Maine, which owns dispensaries in Hallowell, Portland, Thomaston and Brewer. The Maine Department of Health and Human Services cited the Auburn facility for 20 violations of program rules and state law, including illegal pesticide use on plants.

Last week, an employee reported that a majority of Wellness Connection workers at its five locations have joined the United Food and Commercial Workers Union, a national group of 1.3 million members, mostly working in meat- and food-packing industries. However, a union official said Wellness Connection was resistant to granting the union recognition.

Becky DeKeuster, Wellness Connection’s executive director, wouldn’t comment on the company’s plans for the union but said the workforce was free to negotiate.

DHHS has said that while virtually all the marijuana on Wellness Connection shelves was treated with pesticides, it won’t remove the product from the market, but will instead allow patients to decide whether they want to buy it or not.

DeKeuster said about 20 percent of marijuana being sold was treated. But Kenneth Albert,  a DHHS official who oversees medical marijuana licensing and regulation, disputed that figure and said the number is “closer to 100 percent.”

Five of the nine pesticides the state found in Wellness Connection products are approved for use on tobacco, according to a Maine Board of Pesticides Control analysis for the Portland Press Herald. A state toxicologist said all the active ingredients in the pesticides found are either natural substances or synthetic versions of natural substances. 

But any pesticide use on marijuana is illegal under state and federal law, as well as medical marijuana program rules, and little is known about the effects of smoking marijuana treated with any sort of pesticide.