A news release from Quest Diagnostics said the incidence of amphetamine use rose by about 6% last year among the more than 7.2 million workplace drug tests the company performed between January and December 2004. According to Quest, that compares with year-over-year amphetamine increases of 16%, 17% and 44%, between 2000 and 2003, respectively.
The much smaller increases in workers failing tests for amphetamines last year came as the number of workers testing positive for all drugs was unchanged at 4.5%.
Of workers who tested positive in 2004, 55% failed the screening for marijuana (down from 60.2% in 2000) and 13.8% for cocaine (down slightly from 13.9% in 2000). Positive results for barbiturates dropped from 3.5% in 2000 to 2.7% in 2004, according to the Quest data.
A ccording to the company, its data examines positive drug test results for three worker groups: Federally-mandated, safety-sensitive workers; the general workforce; and the combined US workforce. Federally-mandated, safety-sensitive workers include pilots, bus and truck drivers and workers in nuclear power plants, for whom routine drug testing is mandated by the US Department of Transportation and the Nuclear Regulatory Commission.
During 2004, the positive drug result rate for federally-mandated, safety-sensitive workers decreased to 2.3% from 2.5% in 2003, while the rate for the general US workforce declined to 4.9% from 5.0% in 2003, Quest said.