[1] (*) SCIENTIFIC AMERICAN, March 1990, p 18. `Science and the Citizen: Test Negative' by John Horgan

What underlies the broad acceptance of ... [drug testing] ...? One factor may be the alarming statistics cited by testing advocates to demonstrate high costs of drug abuse. Examination of some of these claims suggests that they do not always accurately reflect the research on which they are based. ...

Last Year President George Bush declared that “drug abuse among American workers costs businesses anywhere from $60 billion to $100 billion a year in lost productivity, absenteeism, drug-related accidents, medical claims, and theft.” ... All such claims are derived from a single study, one that “was based upon assumptions that need additional validation,” according to an assessment last year from NIDA ...

The study grew out of a survey ... by the Research Triangle Institute (RTI) in 1982. The RTI group found that the average income of households with at least one person who admitted to having *ever* used marijuana daily was 28 percent lower ... The RTI researchers defined the difference in income as “loss due to marijuana use”; the total loss, when extrapolated to the entire population, came to $26 billion. The researchers then added on the estimated costs of drug-related crime to arrive at a total of $47 billion for “costs to society of drug abuse”. This figure – “adjusted” to account for inflation and population increase -- represents the basis of Bush's statement.

The RTI survey included questions on current drug use ... there was no significant difference between the income of households with current users of any illegal drug ... and the income of otherwise similar households. Does this mean that current use of even hard drugs -- as opposed to perhaps a single marijuana binge in the distant past -- does not lead to any “loss”?

Perhaps the study most publicized of late by testing proponents involves employees of the U.S. Postal Service.

This study may be distorted by more subtle biases -- ... minority postal workers tested positive at a much higher rate than non-minority workers and that previous studies have shown minorities to have higher absenteeism.