The use of crystal methamphetamine, commonly known as ice, in the workplace climbed slightly to 0.7 percent in the third quarter from the previous quarter’s 0.4 percent — its lowest level since 2004, according to Honolulu-based drug testing firm Diagnostic Laboratory Services Inc. 

However, the statistics are an improvement from the 1.1 percent workplace usage found in the first quarter of 2011, said Carl Linden, DLS scientific director of toxicology.

Hawaii’s meth use was 410 percent greater than the national average in a five-year study released last month by Quest Diagnostics, a major mainland drug tester.

 “Though the Hawaii comparison to the mainland sounds dramatic, one must be aware, that when comparing small numbers, percentages seem very large,” Linden said. “In this case meth positives of 0.1 percent on the mainland compared to 0.7 percent in Hawaii.”

 Synthetic urine use fell slightly to 1.4 percent from 1.6 percent, similar to the use of marijuana, which dropped to 3.0 percent from 3.2 percent and cocaine to 0.3 percent from 0.4 percent. Opiate use was unchanged at 0.2 percent 

The quarterly sample size includes between 7,000 to 10,000 drug tests.