This news from the National Highway Traffic Safety Administration is probably not that surprising but the extent of the problem is cause for concern. The NTSB says more than half of drivers involved in fatal motor vehicle accidents had drugs or alcohol in their systems. Government researchers examined accidents in 14 states – Florida was not one of them – and found that men and people of both sexes who drive at night were most likely to have alcohol, marijuana, prescription medication or illegal drugs in their systems. While the effects of the alcohol detected in an autopsy can be predicted, officials cannot be certain exactly how impaired a driver on legal prescription medications or illegal drugs might have been.
The government investigators looked at 20,150 deadly crashes that occurred between 2005 and 2009. Fifty seven percent of drivers tested positive for alcohol, and at least one in five had more than one legal or illegal drug in their systems. Alcohol was the number-one drug found, followed by marijuana and stimulants including Adderall and amphetamines. Blacks and whites were equally likely to test positive for drugs, Asians less so and Native Americans more. More than 60 percent of men tested were impaired, while less than 50 percent of women tested positive.
The “great unknown” for safety and accident prevention experts is precise information about the effects of each drug on the individual. States do not have uniform rules for testing. The timing for taking blood or urine samples or what drugs police look for, vary from state to state. The federal investigators say the amount of alcohol consumed can be directly correlated to impairment, but impairment caused by prescription or illicit drugs is not as predictable. For example, traces of marijuana may still be present weeks after it was smoked or consumed.
Prescription medications are an even greater puzzle for those trying to determine when a driver should not be behind the wheel. Some anti-anxiety medications may increase the risk of having an accident, for example, but that has not been conclusively proven. The study’s co-author says more testing, and more consistent testing, is needed to figure out when a driver’s medication intake, other than just alcohol alone, is enough to make that driver a potentially fatal risk to the other unsuspecting drivers who are sharing the road.
Source: Reuters Health, “Alcohol, drugs common in fatal crashes,” 9/6/12