More workers test positive for cannabis as states legalize it

The percentage of American workers testing positive for marijuana increased to 2.7 percent, up from 2.5 percent in 2019, according to Quest, the drug-testing laboratory. “We haven’t really seen a sea change in the overall testing rate [for drugs], but we’ve been seeing changes in the degree to which marijuana is included in the testing panels,” said Dr. Barry Sample, Quest’s senior director for science and technology.