Roughly a quarter of all road accidents in European countries occur due to alcohol use, says a new report from the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA).

"Around 30 000 people die in traffic accidents in the EU every year, with alcohol still the number one substance endangering lives on Europe's roads," EMCDDA said in a news release.

The data comes from Driving Under the Influence of Drugs, Alcohol and Medicine, a largest ever study of its kind conducted in the EU. The research was conducted between 2006 and 2011.

The research included 13 European countries. More than 50,000 car and van drivers were tested in for traces of 25 substances, including illicit drugs, alcohol and medicines during random surveys.

3.5 percent of the drivers tested positive for alcohol, 1.9 percent used illicit drugs and 1.4 percent medicine. About 28 to 53 percent of people involved in roadway crashes that occurred in nine countries had tested positive for psychoactive substances.

The study showed that higher prevalence of cannabis, alcohol and cocaine occurred in southern and western region of Europe. Alcohol use was more prevalent in men while medicine was identified, more often than not, in women drivers.

The report highlighted the fact that drinking driving poses a serious health risk.

"As the risk and share of injuries is higher for alcohol, targeting driving under the influence of alcohol should always be the first priority of law enforcers," the report said.

Drinking and driving is the leading cause of road accidents across the world. The prevalence of fatally injured drivers having excess alcohol in their blood while driving ranges from 20 percent in developed countries to as high as 69 percent in developing countries.

In the U.S., alcohol is involved in 37% of all traffic deaths among people aged 16 to 20, according to National Institutes of Health.