A VERY IMPERFECT SYSTEM

ACCORDING to a report by the European Monitoring Centre for Drugs and
Drug Addiction (EMCDDA), studies are equally divided on whether
cannabis or prescription drugs containing benzodiazepines are the
main culprits in drug-related road accidents.

"As the number of such studies grew, it became clear that illicit
drugs were not the only psychoactive substances used by drivers: a
significant number were found to have psychoactive medicines in their
bloodstream, including opioid painkillers such as codeine,
antidepressants and sedatives," said the report.

In 1999, a study of drug use among drivers in different European
countries concluded that overall the prevalence of drug use was
probably in the range of 1-5 per cent for illegal drugs and of 5-15
per cent for legal drugs.

The results varied from country to country.

The main benzodiapezines identified were diazepam, alprazolam,
temazepam, oxazepam and clonazepam.

Of the eight European studies of drivers killed, four found
benzodiazepines to be the most common class of drug present, compared
with two in which cannabis was found to be more prevalent. Two
studies found other substances, such as amphetamines in Norway and
cocaine in Spain, to be the most prevalent.

The report also covered testing on narcotest devices.

"At the end of the period, none of those devices met the criteria,"
it said. Six devices registered a failure rate of greater than 25 per cent.

Another problem found was that smokers and amphetamine users produce
less saliva, and so there were difficulties in obtaining the
necessary sample quantities in a reasonable time interval.

"Thus, at the end of the study no device was considered to be
reliable enough in order to be recommended for roadside screening of
drivers," it concluded.

"Without such objective devices, specialised training of traffic
police to recognise the signs of drug impairment in drivers is
increasing, but remains somewhat sporadic in most countries;
mandatory training, which is recommended, remains rare."

At the present time, it said, without the benefit of reliable
technology, police at the roadside are not expected to distinguish
which particular drug or combination of drugs may be affecting the driver.

In Cyprus, it added, qualitative information collected by the traffic
control department of the police revealed lack of awareness of the
impairment and other consequences of driving under the influence of
cannabis and benzodiazepines,

"Public perceptions of the dangers of each substance do not
necessarily reflect scientific evidence, and the correction of these
perceptions is crucial to the success of future prevention
initiatives," the report said.