Whatever threat online pornography might pose to society's morals, online music might pose a bigger threat to society's computers.
A study scheduled to be released today found that about 9% of adult sites that turned up high in search-engine rankings had such PC-damaging problems or annoyances as spyware, adware and spam associated with them.
Yet searching for digital music was twice as risky -- more than 19% of the sites produced by such queries were risky for computer users, according to the study by McAfee Inc., a Santa Clara, Calif.-based company that makes computer-security software.
Other risky searches included those for electronic gadgets and for background "wallpaper" to decorate computer screens.
Researchers have one idea why looking for porn appears to be safer: The business side of that industry works even without the extra hustling.
Since it's harder to make a living selling digital music, those hawking such items are far more likely to attach programs that spew unwanted ads or worse.
"The tier-one adult sites are doing phenomenally well as businesses, and because of that they very much have their house in order," said McAfee Senior Product Manager Mark Maxwell.
The digital music searches studied include those for such file-sharing programs as BearShare, which often include intrusive advertising programs. BearShare took the honors as the single riskiest search term, returning unsafe sites at a 46% rate.
Other findings from McAfee's database were not included in the study, including the news that Britney Spears is slightly more dangerous to search for than Lindsay Lohan.
The former couple of Brad Pitt and Jennifer Aniston, meanwhile, are a 36% more hazardous combination than the current pair of Pitt and Angelina Jolie.
The study is the third of its kind from McAfee, which owns a popular free service called SiteAdvisor.
It rates millions of websites as red for risky, yellow for somewhat risky and green for safe, warning Web surfers before they click through.
The latest paper also found that sponsored search results, which are paid for by advertisers, are twice as likely to be risky as regular search results.
It also compared the five most popular search engines, finding that Yahoo Inc. had the safest unpaid results and the riskiest paid results.
For thousands of popular searches, the top 500 unpaid listings were about as safe at one search engine as they were at another.
Yahoo came out best with 2.7% that were red or yellow, and IAC/InterActiveCorp's Ask.com was the worst at 3.3%.
The range was larger when it came to advertised results: from a low of 4.1% problematic results at Ask to 9% at Yahoo.
Google Inc. has toughened its checks on advertisers and made its paid results safer in the last year, McAfee said, while Yahoo has gotten worse.
Yahoo declined an interview request. In a statement Saturday, Vice President of Marketplace Quality Reggie Davis wrote that the unpaid search results "represent the vast majority of clicked links."
"We will continue to improve our performance in this area by investing in technology," Davis said.
An Ask.com spokeswoman pointed to the company's sharp improvement in paid results, which boosted its overall safety performance from worst to the middle of the pack.
Many of the advertised sites that McAfee flagged are obvious scams pointed out by SiteAdvisor users, including those that make impossible claims about obtaining green cards for immigrants and repairing damaged credit.
"We are struck by search engines' failure to block even the most notorious and widespread of scam ads -- a decision we suspect arises out of search engines' business objectives," the study's authors wrote.
In better news, the number of the very worst sites -- those that use known vulnerabilities in software to automatically install keystroke loggers and other malicious programs -- remained quite small. McAfee turned up less than one in a thousand among the top search engine results.
Google has begun to warn users before they go to one of those sites, and a spokeswoman said that the effort would remain the priority over fighting such lesser threats as adware and spam.
"Google concentrates on Web pages that pose real danger to our users, and we are confident that we are protecting searchers from these threats," company spokeswoman Katie Watson said.