Marijuana use has risen slightly among Hawaii workers, a quarterly report shows.

Workforce drug tests by Diagnostic Laboratory Services Inc. showed that pot use climbed to 2.6 percent in the fourth quarter of 2016 from 2.3 percent in the year-earlier period.

“The level of workplace substance abuse seems to be fairly consistent,” said Carl Linden, DLS’ scientific director of toxicology. “It’s still a problem, basically. It’s not going away.”

Meanwhile, fewer workers tested positive for cocaine, which dropped to 0.3 percent from 0.4 percent. Opiate use also fell to 0.2 percent from 0.3 percent. Opiates prescribed by a doctor are not included in test results.

Amphetamine use was unchanged at 0.7 percent.

The percentage of workers testing positive for synthetic urine — used to mask drug use — rose to 0.9 percent from 0.8 percent in the fourth quarter of 2015.

DLS’ sample size typically includes between 7,000 and 10,000 drug tests.