"After four straight years of increases, in 2016, urine testing positivity for heroin, indicated by the presence of the 6-acetylmorphine (6-AM) metabolite, held steady in the general U.S. workforce and declined slightly among federally-mandated, safety-sensitive workers.

"Amphetamines (which includes amphetamine and methamphetamine) positivity continued its year-over-year upward trend, increasing more than eight percent in urine testing in both the general U.S. and federally-mandated, safety-sensitive workforces compared to 2015. Throughout the last decade, this rise has been driven primarily by amphetamine use which includes certain prescription drugs such as Adderall®.

"The positivity rate in urine testing for cocaine increased for the fourth consecutive year in the general U.S. workforce and for the second consecutive year in the federally-mandated, safety-sensitive workforce. Cocaine positivity increased 12 percent in 2016, reaching a seven-year high of 0.28 percent, compared to 0.25 percent in 2015 in the general U.S. workforce, and seven percent among federally-mandated, safety-sensitive workers to 0.28 percent, compared to 0.26 percent in 2015."

"A drug’s metabolite is the compound produced when the body processes a particular drug. Identifying these compounds is the focus of workplace drug testing analysis. Marijuana possesses the greatest total number of detectable metabolites at 31 but fewer major components. For amphetamines, no metabolites are identified because these substances normally pass through the body essentially unchanged in chemical structure."

"Marijuana positivity continued its upward climb in both the federally-mandated, safety-sensitive and general U.S. workforces. In oral fluid testing, which detects recent drug use, marijuana positivity increased nearly 75 percent, from 5.1 percent in 2013 to 8.9 percent in 2016 in the general U.S. workforce. Marijuana positivity also increased in both urine testing (2.4% in 2015 versus 2.5% in 2016) and hair testing (7.0% in 2015 versus 7.3% in 2016) in the same population.

According to Quest Analytics, the drug positivity rates in 2018 of people in the US who were subjected to urine drug tests as a condition of employment are:
Federally Mandated Safety-Sensitive Workforce: 2.7%
General US Workforce: 5.1%
Combined US Workforce: 4.4%

Click here for the complete datatable of Drug Positivity Rates Of US Employees Subjected to Urine Drug Tests, by Worker Category