CHAPEL HILL - Recreational boat passengers are just as likely as operators to die as a result of drinking alcohol, according to a new study of boating deaths in North Carolina and Maryland. One reason the study revealed was that passengers who have been drinking often topple overboard and drown.
Researchers at the University of North Carolina at Chapel Hill and Johns Hopkins University say their results indicate that efforts to reduce boating deaths that target only operators fail to protect many boaters at risk. Different approaches that will address all boat occupants are needed.
"It's not just crashing into other boats or piers that is causing the deaths," said Dr. Robert D. Foss, research scientist at the UNC Highway Safety Research Center. "Frequently, people who have been drinking fall in the water even if a boat is not moving, become disoriented and drown."
Actress Natalie Wood apparently died that way 20 years ago in November after falling off her stationary yacht in California.
A report on the study appears in the Dec. 19 issue of the Journal of the American Medical Association. Besides Foss, authors include Drs. Gordon S. Smith, Penelope M. Keyl and Jeffrey A. Hadley of the Johns Hopkins University Center for Injury Research and Policy, Dr. James McKnight of the Pacific Institute for Research and Evaluation, William Tolbert of Rho Inc. of Chapel Hill and Christopher Bartley of the UNC Highway Safety Research Center.
The population-based, case-control study involved reviewing 221 boating deaths recorded in North Carolina and Maryland medical examiner files between 1990 and 1998 and comparing them with a probability sample of 3,943 boaters from both states. Victims studied were all over age 18. Commercial boat accidents were excluded.
Even with a blood alcohol content (BAC) of only .01 percent, the risk to operators and passengers increased 30 percent over people with no alcohol in their blood, Foss said. The risk of death was more than 52 times greater when victims showed a blood alcohol content of .25 milligrams per deciliter.
"The estimated risk associated with alcohol use was similar for passengers and operators and did not vary by boat type or whether the boat was moving or stationary," Foss said. "People often assume that alcohol-related boating accidents involve a collision," he said. "That happens, of course, but most deaths result from drowning, often when boats aren't moving at all."
About 80 percent of boating fatalities result from drowning, the team found. "Just falling out of the boat and drowning is surprisingly common," he said. "That means prevention activities oriented toward boat operators alone won't work as well as they do with drivers on the roads. If you've got a stone-cold sober boat operator and an impaired passenger, that passenger is still at high risk."
The "crazed drunken boater" ramming his boat into a dock or another boat is "a pretty rare phenomenon," Foss said. As a result, simply using a designated driver for a boat or setting a blood alcohol content limit for boat operators leaves much of the problem unaddressed.
Besides analyzing medical examiner data, investigators spent three summers interviewing and obtaining breath measurements from boaters across North Carolina and Maryland as part of their research.
"Before we did the study, we had a fairly good idea about the risk curve for drinking drivers on the road, but we had no idea about the risk for boaters who had been drinking," Foss said. "This study gives us the first look at the shape of the risk curve for boaters."
The National Institute on Alcohol Abuse and Alcoholism supported the research. About 800 people died in the United States in 1998 from recreational boating accidents, and early studies have linked more than half such deaths to alcohol use.
Countries such as Canada and Finland have even higher proportions of alcohol-related boating fatalities than the United States does, the researchers said.
For more information email Foss at email@example.com.