Privacy advocates are concerned that there's one big flaw with Google Inc.'s free e-mail service: The company plans to read the messages.
The Internet search company says it needs to know what's in the e-mail that passes through its system so they can be sprinkled with advertisements that Google thinks are relevant.
Revenue from those targeted ads will pay for the Gmail service, which began a test last week, offering up to 500 times as much e-mail storage as competing Web e-mail programs from Yahoo Inc. and Microsoft Corp.
The electronic letters will be read by computers, not by Google employees, but the specter of seeing an ad for an antacid beside a message from a friend complaining about stomach pain is enough to make some people nervous about the e-mail service.
"There will undoubtedly be some folks that will see this and freak out," said Ray Everett-Church, chief privacy officer for TurnTide Inc., an anti-spam company in Conshohocken, Pa.
"The privacy implications of going through and perusing a customer's e-mail to display targeted advertising could be the Achilles' heel for Google's services," said Jordana Beebe, communications director for the Privacy Rights Clearinghouse, a consumer group in San Diego.
The consternation caught Larry Page, Google's co-founder and president of products, off guard.
"I'm very surprised that there are these kinds of questions," he said.
Spam-filtering programs routinely scour e-mail for telltale words such as "Viagra," and companies monitor the messages of employees on their corporate networks.
In addition, Internet companies scrutinize Web search terms to serve up ads that are related to the topic a user apparently cares about.
Google's AdSense program goes a step further, placing such ads alongside content on Web sites that come up in search results.
But e-mail is a more personal form of communication, making targeted advertisements feel intrusive, said Chris Hoofnagle, associate director of the Electronic Privacy Information Center in Washington. He likened the Gmail ads to a computerized voice interrupting a phone conversation about a vacation with a pitch for a travel agency.
"This is an expansion in a way that should bother people," Hoofnagle said. "Communications are sacred."
Consumer advocates are also worried about the potential for Google to link Gmail users to their Internet searches.
Google records the numerical Internet addresses of the computers that request each of the Web searches the company performs. But it hasn't had names or other identifying information to link those addresses to specific people and learn who, for example, is searching for "Janet Jackson halftime show."
Once users register for Gmail, Google could make that connection, said Pam Dixon, executive director of the World Privacy Forum in San Diego. And if Google ever compared the two sets of data, she said, "there are some people who would be chilled and embarrassed."
Page wouldn't say whether Google plans to link Gmail users to their Web search queries.
The Los Angeles Times is a Tribune Publishing newspaper.