Nick Coltrain

nickcoltrain@coloradoan.com

In the first year of legalized recreational marijuana in Colorado, the drug showed up on 20 percent more employment-related drug tests performed by Quest Diagnostics, according to the company.

The science behind the drug tests hadn't changed, and Barry Sample, director of science and technology for the employer solutions branch of the company, cautions against reading much into a single year-over-year increase.

"While it's interesting, and it could be a harbinger for things to come, I think it's a little too early to draw conclusions at this point," Sample said, adding that the increase of positive tests warrants further study.

Quest Diagnostics found the increase from 2012 to 2013, the first full year of legal marijuana in Colorado. While the company didn't release the percentage of overall drug screens that returned positive for marijuana — only the increase in such positives — Sample said the company has conducted about 100,000 tests in Colorado each year since 2005.

He didn't have any evidence that employers were changing their screening patterns to reflect Colorado's legalization of recreational marijuana.

Recreational marijuana remains illegal outside of Colorado and Washington state, as the federal government classifies marijuana as one of "the most dangerous drugs … with potentially severe psychological or physical dependence."

"If (employers have removed marijuana from drug screen results), and I'm not convinced it has, it's absolutely minimal," Sample said.

While more employees and potential hires may have tested positive for marijuana since it became legal for adults in December 2012, advocates for the law say it's a sign of an employer problem, not a marijuana problem.

"It would appear the only thing that's actually causing harm to people is these companies' drug testing policies, not employees using marijuana in their off hours," said Mason Tvert, Denver-based communications director for the Marijuana Policy Project.

He predicted a cultural shift before a legal one, especially if local and state businesses start fretting over losing good employees due to their use of a legal substance in their off hours. Tvert also predicted that more people will avoid working for companies that discriminate against marijuana use.

Sample noted that many marijuana users appear to self-select where they work already, based drug screens and survey data.

A lobbyist for pro-business groups, including the Fort Collins Area Chamber of Commerce, said she doesn't think a change to employers' right to dictate drug policy is on the way, at least not legally. Sandra Hagen Solin, of lobbying firm Capital Solutions, said businesses now cover a spectrum of leniency for drug use. Her group and the pro-business interests it represents would oppose any blanket change to drug laws.

She cited issues with employee safety and productivity in relation to marijuana use and pointed out that Amendment 64 specifically states that it doesn't change employer drug policy.

Hagen Solin said that marijuana showing up in someone's system up to 30 days after consumption means there's a question mark on if or how impaired that person may be at work.

Tvert called that argument nonsense and pointed out that a person is typically no longer impaired within hours after use, according to Colorado driving law. According to the National Highway Traffic Safety Administration, the amount of THC, marijuana's active ingredient, in a user's bloodstream typically falls below Colorado's legal threshold within about three hours of consumption, but residual effects have been noted as much as 24 hours after use.

"If an employee is using marijuana on the job, or their marijuana use is harming their performance, that's one thing," Tvert said. "But it's an entirely different thing to fire a good employee for using marijuana in their free time. Really, these are just businesses that are going to lose talent."

Sample, the drug testing official, said marijuana can appear on a drug screen up to 30 days after use, but only in the "proverbial pothead — a very heavy, chronic, habitual user." Someone sharing a joint on a Friday, one who doesn't regularly use marijuana, wouldn't necessarily test positive for it on the following Monday or Tuesday, he said.

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