"Drug testing, particularly on a per student basis, can be relatively costly for schools. The cost of drug tests ranges depending on the quality of the test. A standard drug test used in some high schools can range from $14 to $30 per test (Volpert & Tremaine, 1997). A standard drug test detects marijuana, tobacco, cocaine, heroin, opiates, amphetamines, barbiturates, and tranquilizers. These tests are able to detect the presence of drugs from within a few days of use to as long as a week or more, depending on the drug in question (Bailey, 1998). A drug test for steroid use costs $100 per test, and a drug test that meets the National Collegiate Athletic Association (NCAA) standards for accuracy costs over $200 per test (Volpert & Tremaine, 1997). Alcohol is usually not detected by standard urine drug tests, because it leaves the body quickly; hence, it must be detected with a Breathalyzer test shortly after consumption."

Source

Yamaguchi, Ryoko; Johnston, Lloyd D.; and O’Malley, Patrick M., "Drug Testing in Schools: Policies, Practices, and Association With Student Drug Use," Institute for Social Research (Ann Arbor, MI: The University of Michigan, 2003), p. 1.
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