More employers are quietly taking what once would have been a radical step: Dropping marijuana from the drug tests they require of prospective employees. (John Locher/AP)

One of the largest U.S. drug-testing laboratories has analyzed its millions of urine drug test results by industry for the first time, and found the two industries with the highest rate of positive test results for marijuana were also two that have to deal with consumers.

Some 5.3 percent of tests given to retail trade workers, and 4.7 percent of those given to health care and social assistance workers came back positive, according to an analysis by Quest Diagnostics.

The analysis, which comes from examining more than 10 million test results that are part of the lab company’s Drug Testing Index, found that five of 16 industries saw double-digit increases in the rate of positive test results between 2015 and 2017.

They included not only retail but transportation and warehousing, finance and insurance and wholesale trade, showing an increase in positive test results at a time when more states are loosening restrictions on pot use and more companies are said to be loosening drug testing restrictions amid low unemployment.

Barry Sample, the senior director of science and technology for Quest Diagnostics Employer Solutions, said the results of the new analysis did not surprise him.

“We’ve been reporting year-over-year increases of the positivity rates for almost all three of these illicit drug classes,” he said, referring to marijuana, cocaine and methamphetamines. “As we break it out by industry we’re seeing a number of industries with those same results.”

Still, the rate of growth stood out. The retail industry, for instance, saw a 43 percent increase in positive test results for cocaine between 2015 and 2017, Quest’s analysis showed. And eight sectors saw at least 20 percent increases in positive marijuana test results over the same period, as more states loosened laws restricting the drug.

“Clearly I think that there are likely some attitudinal changes with respect to marijuana, which may be driving some of the increases we’re seeing,” he said.

Sample said, however, that it would be a mistake to attribute the rise entirely to statute changes. Even in states with relaxed laws, he said, the rate of of change in positive test results was often on par with the national average.

Before movie-driven images of a stoned store clerk come to mind, it’s important to note such data doesn’t necessarily measure current impairment. The test results measure use of the drug, not necessarily use of the drug at work, and with pot, in particular, the drug’s byproducts can stay in a person’s system and be detected even weeks after use.

But some labor lawyers say the legalization of marijuana use -- 10 states and Washington D.C. allow for recreational use of pot, while 33 states and D.C. have legalized it for medical use -- is having a big effect on how employers view employee use of the drug.

"What I see employers doing is evaluating the positions, asking ‘is this really a safety-sensitive position?’ " said Erin McLaughlin, a labor and employment lawyer with Buchanan, Ingersoll & Rooney based in Pittsburgh. "If it’s not, then there are more employers who are taking the position ‘let’s not test for marijuana.’ "

She believes the tight labor market is also clearly playing a role. “Absolutely, I think in positions where there is a labor shortage right now and employers are looking for candidates for jobs that don’t have safety-sensitive issues or aren’t federally regulated [to require testing], I definitely think employers are eliminating drug testing as a whole when it comes to hiring applicants,” she said.

She pointed to the construction industry, where there are big labor shortages, and said she’d seen it with some retail clients. “Quite frankly, for jobs like a cashier, a sales associate -- many of them don’t do drug testing at all, especially considering the labor shortage.”

James Reidy, a labor and employment lawyer with Sheehan Phinney in New Hampshire, said he’s seeing similar responses.

“A lot of companies are recognizing if I drug test at the post-offer, pre-employment position, I’m going to lose out on people,” he said.

As perceptions shift and legal use of marijuana becomes more common, he said, "it’s really become the new ‘don’t ask, don’t tell,’ " with many employers preferring not to know about an employee’s use. “If he’s got a positive drug test, and you knew,” Reidy said of an employee later who might later have a safety accident, “it’s in your system.”

Quest’s Sample said the lab company’s attrition rate of employers ending drug tests with the company has actually been showing decreases, that volume is not down, and that in states where recreational use is allowed, they were only seeing minor drops in the percentage of employers who included marijuana in their panel of drug tests.

But he said his data was not able to detail whether some employers may be shifting which groups of new candidates or employees they test, and that what employers do with the test results after they have them may be shifting. “The economy is robust and people are still hiring,” he said. “It’s harder to find qualified candidates and those employers may be opting to change how they view a positive test for marijuana.”

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