If you hear the sound of running water the next time you call a co-worker on his or her mobile phone, don’t be surprised. Three-fourths of Americans with mobile phones say they use them in the bathroom, a new study shows.

Approximately the same number of men and women have used the phone in the bathroom, according to a survey of 1,000 Americans by 11mark, an integrated marketing agency, although men seem more tethered to IT in the toilet: 30 percent of men versus 20 percent of women agreed with the statement, "I don't go to the bathroom without my mobile phone."

More than half the surveyed users (63 percent) said they have answered a phone call in the bathroom, and almost half (41 percent) reported initiating a phone call. That's not all, however: What goes on behind the walls of the stalls is anything a mobile phone is capable of. Sixty-seven percent said they have read a text, and 39 percent have surfed the Web.  Men work more from the bathroom—20 percent said they have participated in work-related calls, versus 13 percent of their female colleagues.

As expected, Gen Y respondents are the pacesetters in the "mobile everywhere" movement, with 91  percent using their phone in the bathroom. Still, older generations are not far behind. Eighty percent of Gen X reported using the phone in the bathroom, as did 65 percent of Baby Boomers and 47 percent of the Silent Generation.

While online, they are doing more than just surfing; 16 percent of Gen Y report they have made an online purchase while in the bathroom. Users of iPhones are particularly likely to browse and buy in the bathroom – 22 percent have made a purchase, versus 10 percent of Americans with mobile phones overall.

"The writing is on the stall," said 11mark principal Nicole Burdette. "This study confirms what we all know: that the last private place is no longer private."

In the process, high-tech hygiene is taking a hit, the survey found. While 92 percent of mobile phone users said they wash their hands after using the bathroom, only 14 percent said they wash their phones.

Reach BusinessNewsDaily senior writer Ned Smith at nsmith@techmedianetwork.com. Follow him on Twitter @nedbsmith.

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