Washing their hands in public restrooms is a habit slowly heading towards extinction among American men, according to some unusual new research.

The American Society for Microbiology and the Soap and Detergent Association sponsored an interesting study that saw researchers discreetly observe people going into public restrooms.

The locations were six bathrooms in four major cities: Atlanta's Turner Field, Chicago's Museum of Science and Industry and the Shedd Aquarium, New York's Penn and Grand Central train stations, and San Francisco's Ferry Terminal Farmers Market.

The monitoring occurred between Aug. 17 and Aug. 25 of this year. The sites were the same as in a previous survey that now shows Americans were washing their hands more frequently two years ago.

Reporting their findings at a meeting of the American Society for Microbiology this week, the researchers had some disturbing hygiene habits to reveal.

Only 77% of the men and women going to public restrooms washed their hands with soap and water, a 6% decline from 2005.

Significantly fewer men were seen soaping up: 66% in 2007, as opposed to a more encouraging 75% in 2005. Women appeared as preoccupied with the hygiene of their hands this year as they did two years ago: 88% washed up in 2007, compared to 90% in 2005.

“Guys need to step up to the sink,” Brian Sansoni, spokesman for the Soap and Detergent Association, commented.

Interestingly enough, in a separate telephone survey, 92% of the respondents claimed they always wash their hands in public restrooms and at home.

More than 6,000 American adults were observed in regard to their hand washing habits, while over 1,000 participated in the telephone survey.

Chicagoans were the most concerned about their hands’ hygiene, with 81% of men and women lathering up. New York followed, with 79% washing up, followed by Atlanta (75%) and San Francisco (73%).

The American Society of Microbiology emphasizes that hand washing is crucial in order to prevent spreading various infectious diseases.