Marijuana exposure incidents, or 'pot poisonings,' have spiked in Washington state, especially among teenagers, in a trend experts said on Tuesday appears to be linked to the state's largely unregulated medical marijuana industry.

Marijuana exposures are defined as any situation where an adult or child suffers an adverse reaction to the consumption of marijuana, such as increased heart rate, paranoia or stomach illness, according to the Washington Poison Center.

Some 210 marijuana exposures were reported in the first nine months of the year, more than in all of 2013, according to Washington Poison Center Clinical Managing Director Alexander Garrard.

"Our thought is that the spike is potentially related to the number of unlicensed medical marijuana dispensaries that are opening up around the state," he said.

Washington legalized recreational marijuana use in 2012, with the first retail stores opening in 2014 under a highly regulated and taxed system in contrast to the relatively lax pre-existing regime for medical pot.

The state's medical marijuana industry, legalized in 1998, sells products of unconfirmed potency as well as marijuana edibles attractive to children, like gummy bears and lollipops.

While retail stores have been slow to open, Garrard said medical dispensaries have been expanding steadily over the past year.

He said most exposures among young children are accidental, with parents reporting their children found and ate marijuana-laced items such as cookies and candy bars.

Exposure incidents among teens ages 13 to 19 have seen the biggest spike, a trendline possibly linked to accessibility, Garrard said. There were 39 teen exposures in all of 2013, with almost as many reported this year through August, data shows.

"A kid may have access to it (medical marijuana) and who knows what they are doing with those products when they go to school, and they are hanging out with their friends," Garrard said. "It's really hard to track that information."

Marijuana detractors argue the push to legalize pot, which remains illegal under federal law, comes amid a lack of clear data about how cannabis affects young brains and bodies.

Garrard urged anyone suffering from illness linked to marijuana to report the incident to the poison center, which keeps patient information confidential.

"A lot of what we know about these adverse effects comes from these case reports or people having shown up in the hospital," he said.