Pubdate: Thu, 01 Mar 1990
Source: Scientific American

TEST NEGATIVE

A look at the "evidence" justifying illicit-drug tests

More than eight million working Americans had their urine tested for
illegal drugs in 1989, and as many as 15 million will undergo such
testing this year, according to the National Institute on Drug Abuse
(NIDA).  The fraction of companies that subject employees or job
applicants to testing has jumped from 21 percent in 1986 to more than
50 percent last year, according to the American Association. The trend
seems likely to continue: a majority of the respondents to a recent
Gallup poll favored random drug testing of all workers.

What underlies the broad acceptance of a practice that conservative
Supreme Court Justice Antonin Scalia has called a "needless indignity"?
One factor may be the alarming statistics cited by testing advocates to
demonstrate the high costs of drug abuse. Examination of some of these
claims suggests they do not always accurately reflect the research on
which they are based. In fact, some of the data could be used to
"prove" that drug use has negligible or even beneficial effects.
Consider these examples.

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." Variants of this statistic abound
in discussions about drug abuse and are commonly repeated without
qualification by the media. Yet all such claims derive from a single
study, one that "was based upon assumptions which need additional
validation," according to an assessment last year by NIDA, the chief
federal agency sponsoring research on substance abuse.

The study grew out of a survey of some 3,700 households by the Research
Triangle Institute (RTI) in 1982. The RTI group found that the average
reported income of households with at least one person who admitted to
having ever used marijuana daily (20 days or more in a 30-day period)
was 28 percent lower than the average reported income of otherwise
similar households. The RTI researchers defined that difference in
income as "loss due to marijuana use"; the total loss, when
extrapolated to the general population, came to $26 billion. The
researchers then added on the estimated costs of drug-related crime,
health problems and accidents to arrive at a grand 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, according to Henrick J.  Harwood, who headed the RTI
study and is now in the White House drug-policy office.

The RTI survey included questions on current drug use (at least once
within the past month). Yet according to Harwood there was no
significant difference between the income of households with current
users of any illegal drug - including marijuana, cocaine and heroin -
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"? "You
would be on safe ground saying that," Harwood replies.

Officials of the U.S. Chamber of Commerce have testified before
Congress and at national conferences on drug abuse that employees who
use drugs are "3.6 times more likely to injure themselves or another
person in a workplace accident ... [and] five times more likely file a
workers' compensation claim." The pharmaceutical giant Hoffmann-La
Roche, which is leading an anti-drug campaign among businesses (and has
a big share of the drug-testing market), also promulgates this claim in
"educational" literature.

In fact, the study on which the claim is based has "nothing to do with
[illegal] drug users," according to a 1988 article in the University of
Kansas Law Review by John P. Morgan of the City University of New York
Medical School. Morgan, an authority on drug testing, has traced the
Chamber of Commerce claim to an informal study by the Firestone Tire
and Rubber Company of employees undergoing treatment for alcoholism.

In an interview with SCIENTIFIC AMERICAN, J. Michael Walsh, who heads
NIDA's applied research division and is a strong supporter of workplace
testing, singled out two studies that he said showed drug users are
more likely to cause accidents, miss work and use health benefits.  The
studies were done at two utilities: the Utah Power and Light Company
and the Georgia Power Company. The 12 workers in Utah and the 116 in
Georgia who served as the primary research subjects were tested "for
cause": they had either been involved in accidents, exhibited other
"problem" behavior (commonly, high absenteeism) or submitted to
treatment for alcoholism or drug abuse. Critics point out that it
should not be terribly surprising if these subjects exhibited the cited
traits at a higher-than-average rate.

What may be surprising is that, according to a report published by NIDA
last year, Utah Power and Light actually "spent $215 per employee per
year less on the drug abusers in health insurance benefits than on the
control group." Those who tested positive at Georgia Power had a higher
promotion rate than the company average. Moreover, Georgia workers
testing positive only for marijuana (about 35 percent of all positives)
exhibited absenteeism some 30 percent lower than average. Nationwide,
Morgan says, marijuana accounts for up to 90 percent of all positive
findings, both because it is by far the most widely used illegal drug
and because it persists in urine for up to a month (compared with two
days for most other drugs).

Perhaps the study most publicized of late by testing proponents
involves employees of the U.S. Postal Service. The service tested 4,396
new hirees in 1987 and 1988 and - keeping the test results confidential
- tracked the performance of positives (9 percent of the total) and
negatives. By last September, the service reported, 15.4 percent of the
positives and 10.5 percent of the negatives had been fired; the
positives had also taken an average of six more sick days a year.

This study may be distorted by more subtle biases - related to race,
age or gender - than those displayed by the utility studies, according
to Theodore H. Rosen, a psychologist and a consultant on drug testing.
Indeed, Jacques L. Normand, who headed the study, acknowledges that
minority postal workers tested positive at a much higher rate than
nonminority workers and that previous studies have shown minorities to
have higher absenteeism.