A Quest Diagnostics analysis published on May 18, 2023 found that positive post-accident marijuana tests were at the highest level in 25 years in 2022. Positive post-accident tests increased to 7.3%, an increase of 9% compared to 6.7% in 2021. Positive post-accident tests have been steadily increasing since 2012, with a 204.2% increase over a ten-year period.

According to Quest Diagnostics, the increase in positive tests corresponds to the legalization of marijuana (whether for medical or recreational purposes) in most states across the country.

Despite the increase in positive marijuana tests, the overall drug positive rate based on nine million urine tests remained at 4.6%, the same as in 2021 and the highest rate since 2001. Positivity for marijuana increased 10.3%, an increase to 4.3% compared to 3.9% in 2021. Positivity for amphetamines (both prescribed and illicit) also increased 15.4%, up to 1.5% from 1.3% in 2021.

Positive rates increased in most industries, with the highest increases in the Accommodation and Food Services, Retail Trade, and Finance and Insurance industries. Positive rates increased in states with legalized recreational marijuana (5.7%) and medical marijuana (3.9%), and in those that have not legalized marijuana (3.1%), but positive rates were higher in states with legalized marijuana.

More workers in federally mandated safety-sensitive jobs tested positive for marijuana and amphetamines with positivity rates for safety-sensitive workers increasing to 0.98% for marijuana and 0.75% for amphetamines, a 14% and 8.7% increase respectively.

Post-accident positivity when compared to pre-employment tests for marijuana and cocaine was higher by 58.7% and 230%, respectively, over five years (2018 to 2022). Positivity for heroin (6-AM) in urine tests decreased in the last five years.