“American workers are increasingly testing positive for workforce drug use across almost all workforce categories and drug test specimen types. In the past, we have noted increases in prescription drug positivity rates, but now it seems illicit drug use may be on the rise, according to our data,” said Dr. Barry Sample, Director, Science and Technology, Quest Diagnostics Employer Solutions. “These findings are especially concerning because they suggest that the recent focus on illicit marijuana use may be too narrow, and that other dangerous drugs are potentially making a comeback.”