Ohio's first testing lab for medical marijuana got the green light Thursday from the state to open, which means sales can move forward as cultivators harvest their product and dispensaries decide to open.

North Coast Testing Laboratories LLC of the northeastern Ohio town of Streetsboro passed inspection earlier this week and was awarded a certificate of operation Thursday.

A state-approved lab was the last piece needed to get Ohio's medical-marijuana program started. In October, the first marijuana plants were harvested, and last week, the state approved the first dispensary to open. But before sales can begin, all marijuana must be lab-tested for potency and purity.

State regulators had hoped the first medical marijuana sales would happen by the end of the year. But it's likelier that sales begin in early 2019.

North Coast spokesman Joe Moorhead said the facility needs a few weeks to validate machines before testing product intended for sale.

Labs will test marijuana for pesticides and other contaminants, as well as the levels of THC, CBD and other effective compounds it contains.

North Coast says it can deliver test results within three days to cultivators or product manufacturers, who then can package and label product for sale. A lab at Hocking Technical College in Nelsonville also had an inspection this week but has not yet received a certificate of operation, according to the Ohio Department of Commerce.

Initially, only dried flower for vaping will be available and it will be in limited quantities. Ohio's law allows marijuana-infused oils, tincture, lotions, patches and edibles, which state-licensed processors hope to get to market in spring 2019.

The state also issued provisional licenses Thursday to two more, large-scale medical marijuana growers: Greenleaf Gardens in Middlefield and Certified Cultivators in Dayton. That brings the total number of cultivators to 29: 16 large-scale growers and 13 smaller growers. Greenleaf Gardens prevailed in a lawsuit challenging Ohio's law requiring a certain percentage of marijuana business licenses go to businesses owned or operated by minorities. Certified Cultivators successfully appealed the state's rejection of its application in November 2017.

But the Department of Commerce has taken action to revoke licenses from three growers for failing to meet all the requirements of the provisional license: Terradiol Ohio LLC and Mother Grows Best LLC in Canton and OhiGrow LLC in Toledo.

Nearly 2,200 Ohioans have obtained cards through the Ohio Board of Pharmacy since the agency opened its patient registry Dec. 3. To purchase medical marijuana, a patient must have a physician's recommendation for a state-issued card. Only one of the state's 56 licensed dispensaries is ready to open. Cresco Labs' CY+ dispensary in Wintersville will be ready to sell product when it's available, said spokesman Jason Erkes.

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