"We tried to get a sense of everything the companies are doing on Facebook, YouTube, Twitter, Flickr and iPhone apps and it's amazing how much they're doing," said David Jernigan, director of the Center on Alcohol Marketing and Youth at the Johns Hopkins Bloomberg School of Public Health.
"It's far more than I think most parents or adults are aware of. It's the Wild West without a sheriff," he said.
Internet advertising is policed by the alcoholic beverage industry itself, although the Federal Trade Commission does monitor advertising activity online, The Baltimore Sun reported Monday.
An FTC study in 2008 showed only 1 percent of advertising dollars spent by distillers was spent on Internet ads. But the study is not a definitive assessment of how much impact the spending has.
A dollar spent on Internet advertising goes much farther than a dollar spent on a television ad, the newspaper said.
In a statement, the Distilled Spirits Council -- the industry's chief lobbying arm -- said: "The spirits industry is committed to responsible advertising regardless of the medium. Social networking sites are used primarily by adults, which makes these platforms responsible and appropriate channels for spirit marketers."
That sets up a debate on how many youths participate in various Web sites.
The industry has voluntarily agreed to limit advertising to Web sites in which 71.6 percent of visitors are age 21 or older, as that ratio mirrors the general population, the Sun reported.
However, regardless of the percentage of youths on Facebook, for example -- and Nielsen rates that as 18 percent -- there are still a vast number of unsupervised visitors under the drinking age who use the Web site.
Distillers point out that the National Institute on Drug Abuse said alcohol use among eighth-, 10th- and 12th-graders has dropped to its lowest rate since 1975. They say that suggests their ads are not subverting social goals of responsible drinking.