The National Institutes of Health writes that cannabis is known to have detrimental effects on human performance and may also affect driving adversely. Research supports the need for interventions aimed at decreasing the prevalence of driving under the influence of cannabis, and has indicated that further studies should be conducted in order to investigate the dose-response relationship between cannabis and safe driving. On March 1, 2013 Science Daily has reported, New Study Shows Cannabis Effects On Driving Skills.
New research, which has been published online in the journal Clinical Chemistry, the journal of AACC, shows that cannabis can be detected in the blood of daily smokers for a month after the last intake. Cannabis has been found to be second only to alcohol for causing impaired driving and motor vehicle accidents. In 2009, 12.8% of young adults surveyed reported driving under the influence of illicit drugs and in the 2007 National
Roadside Survey, overall more drivers tested positive for drugs than for alcohol. It has been found that the cannabis smokers had a 10-fold increase in car crash injury in comparison with infrequent or nonusers after adjustment for blood alcohol concentration.
These results have demonstrated, for the first time, that cannabinoids can be detected in the blood of chronic daily cannabis smokers for a month of sustained abstinence. This has been consistent with the time course of persisting neurocognitive impairment which has been reported in recent studies. Dr. Marylin Huestis, of the National Institutes of Health and author on the paper, has said, "These data have never been obtained previously due to the cost and difficulty of studying chronic daily cannabis smoking over an extended period. These data add critical information to the debate about the toxicity of chronic daily cannabis smoking."