Cocaine and amphetamines are on the rise among Hawaii workers, while marijuana use has dropped over the previous year even as pot dispensaries ramp up in the islands.

The number of positive test results for cocaine rose to 0.5 percent in the fourth quarter from 0.3 percent in the year-earlier period, according to the latest workplace drug testing report by Diagnostic Laboratory Services Inc. Positive test results for amphetamines, or “ice,” climbed to 1.1 percent from 0.7 percent, while opiate use remained unchanged at 0.2 percent. The use of fake, synthetic urine used to mask drugs in testing was up slightly to 1.2 percent from 0.9 percent.

“It’s something that we have to be aware of. It’s valuable for employers to do pre-employment drug testing … because there are obviously individuals that are abusing substances that are applying for jobs and you don’t want to hire those individuals,” said Carl Linden, scientific director of toxicology at Diagnostic Laboratory.

There are likely many more drugs being used in the workplace, particularly opioids, but the state does not currently allow workplace testing of hydrocodone and oxycodone, even though the painkillers are blamed for a nationwide opioid epidemic.

“We see it when we confirm the opiates, but we can’t report it until the law is changed,” Linden said. “There would definitely be an increase in opiate positive rates. We have the same problem as the rest of the country of over-prescriptions of synthetic opioids.”

Meanwhile, marijuana use dipped slightly to 2.5 percent from 2.6 percent a year earlier.

“I anticipated an increase in marijuana use when the medical marijuana dispensaries opened, but it hasn’t appeared. There was an uptick in the third quarter — from 2.8 percent in the second quarter to 3.8 percent — but it dropped to 2.5 percent in the fourth quarter for an overall decrease of 4 percent year over year,” Linden said. “The dispensaries opened in August and there was a sharp rise, so I thought that was going to be a trend. The jury is still out, so to speak. We still may see the effects of the medical marijuana industry here in Hawaii as it gets ramped up.”

The quarterly testing sample typically includes 7,000 to 10,000 drug tests.