By Del Jones, USA TODAY

Newer workplace drug tests using hair samples reveal 10 times as many job applicants and employees taking cocaine and methamphetamine than had been found in urine tests.

Quest Diagnostics on Friday will release hair data for the first time that show that in the first half of 2009 cocaine was found in three of every 1,000 urine tests performed on job applicants and employees, whereas hair testing found cocaine in 32 of 1,000. For every 1,000 tests, methamphetamine showed up once in urine and nine times in hair.

Hair tests reveal far more drug users because they show a pattern going back three months, whereas urine tests are better at finding recent one-time use, but only drugs taken within the previous one to three days. Urine tests are best at finding out if drugs were involved in a workplace accident or if a worker behaves suspiciously, but they also allow applicants to abstain from use in preparation for screening.

Urine tests show a decrease in workplace drug users from 13.6% in 1988 to 3.5% now, and Quest says drug use the last few years found in hair tests is also falling.

Urine tests show cocaine use is down 57% since 2005, while hair tests show a 36% decline. Urine tests show methamphetamine use has fallen 64% for that same period, but hair tests show a 55% decline, Quest says. That helps allay employer fears that drug use only appeared to be declining because urine tests were being "beaten," says Barry Sample Quest's director of science and technology.

Hair tests are newer and cost about twice as much as urine tests, which range from less than $15 to $30, depending on the number of tests, says Quest, which tested 9 million employees and job applicants last year. It has performed 840,000 hair tests from 2005 through the first half of 2009, enough to establish confidence in today's first-time release of the data, Sample says.

Quest's findings are not surprising and show differences in the detection window, says drug expert Stephen Higgins, a psychiatry and psychology professor at the University of Vermont.

Calls for the legalization of marijuana have yet to influence the workplace; pot was found in 2% of Quest's tests in the first half of 2009, down gradually from 2.5% in 2005. Substance Abuse and Mental Health Services Administration data show a 0.3% uptick in overall marijuana and hashish use from 2007 to 2008.

No drug is demonstrating an upward trend in the workplace, Sample says.