According to a new study released by McAffee, about 4 per cent of search terms return results for websites that attempt to install spyware and other malicious code on users' computers.

One year after releasing its inaugural study of the safety of search engines, McAfee published an update to "The State of Search Engine Safety."

According to the document, the overall safety risk to search engine users declined by about 1 percentage point, sponsored results those paid for by advertisers remain significantly more risky than non-sponsored results.

Overall McAfee estimated that US consumers still make approximately 276 million monthly searches that lead to Web sites that could compromise online safety.

McAfee conducted the study by analyzing the first 50 search results returned by major search engines like Google, Yahoo and MSN for 2,300 popular keywords.

"We're encouraged to see some improvement in search engine safety this year. But with four out of five Web site visits starting with a search engine query, consumers are still exposed to hundreds of millions of risky searches per month," said Tim Dowling, vice president, Consumer Growth Initiatives, McAfee SiteAdvisor. "In fact, an active search engine user, one that performs more than 10 searches per day, is likely to visit a dangerous site at least once a day."

The study found the highest ratio of risky sites in categories related to music and technology. "Digital music" returned the highest percentage of risky sites at 19.1 percent, followed by "tech toys" and popular keywords like "chat" and "wallpaper."

The names of popular file sharing programmes like "Bearshare" (45.9 percent risky results), "limewire" (37.1 percent) and "kazaa" (34.9 percent) were also high on the list.

Among adult keyword search results, risky sites increased by 17.5 per cent since December 2006, and risky sites now number 9.4 percent of overall adult search results.