When states began legalizing marijuana, people warned that we would soon face an epidemic of people showing up to work high. But it turns out, those fears have not been warranted.

A study conducted by Quest Diagnostics, a major drug test laboratory in the United States, found that the number of workers testing positive for marijuana has barely increased since legalization began. For instance, in Colorado the number of workers testing positive for marijuana went from a little under two percent before legalization to just a little under 2.5 percent two years after legalization. The biggest jump in positive marijuana tests were in Oregon, where it increased from around 2.25 percent to nearly 3.5 percent. So still not a very high percentage.

Quest noted that the increase in positive test results may not even be an effect of marijuana legalization. Nationwide, positive drug test results among employees has also increased from 2012 even in non-legal states. So it's possible that these increases are the result of the same factors as in non-legal states.

To be fair, Quest noted that these results are only valid among companies that do drug test employees. A number of companies, particularly in legal marijuana states, have stopped drug testing employees, or have simply removed marijuana from the drugs that they look for. So it's possible the number of workers using marijuana has increased substantially, they just work in places where they don't take drug tests.

But if they don't take drug tests, then they likely don't work a job that could involve injuring other humans, so it's probably not such a big deal.

In short, legal marijuana hasn't turned employees in these states into lazy slobs who can't get any work done. 

(h/t CBS News)