About four in every 10 U.S. youngsters age 10 to 17 report they've seen pornography while on the Internet, two-thirds of them saying it was uninvited, according to a study published on Monday.
Many of the encounters with online pornography, both sought-out and accidental, were related to use of file-sharing programs to download images, the report from the University of New Hampshire in Durham said.
"Although there is evidence that most youth are not particularly upset when they encounter unwanted pornography on the Internet (it) could have a greater impact on some youth than voluntary encounters with pornography," the study said.
"Some youth may be psychologically and developmentally unprepared for unwanted exposure, and online images may be more graphic and extreme than pornography available from other sources," it added.
The report, published in the February issue of Pediatrics, the journal of the American Academy of Pediatrics, was based on a telephone survey made of a representative sample of 1,500 U.S. youngsters from March to June, 2005
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