Business is booming for sex workers in Silicon Valley, but it's becoming increasingly risky.

Startups are transforming into multi-billion companies. And the staffs are overwhelmingly male. Sex workers tell CNNMoney they have a growing clientele who have plenty of excess cash.

Two recent events have raised concerns.

The arrest this week of an alleged prostitute, Alix Tichelman, in connection with the death of Google executive Forrest Timothy Hayes has prostitutes worried about the impact on business.

"I do worry that people are going to think that this is something that's normal and happens, but it really doesn't," said "Maxine Holloway" a high-end prostitute working in Silicon Valley. (To protect their privacy, CNNMoney agreed to use pseudonyms or the professional names of the sex workers we spoke with for this story.)

Other sex workers CNNMoney spoke to expressed worry as well -- though none said they had experienced cancellations.

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A second issue affecting business was the shut down of a prominent website for both solicitation and screening of prostitutes and their clients.

Late last month, the FBI raided and shut down MyRedbook, a website that allowed escorts to advertise their services and negotiate with clients.

Women in the industry relied heavily on MyRedbook to do background checks on their clients. Sex workers would post about instances of violence or circumstances in which they felt unsafe.

Without MyRedbook, prostitutes are having a difficult time vetting their clients.

"It's like sex workers lost their Yelp," said Bay Area sex worker and activist "Siouxsie Q."

Male clients also used the site to review and discuss their experiences.

That's why call girls say that the further underground sex work goes, the more dangerous it is for everyone involved.

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Hayes did not solicit Tichelman on MyRedbook; according to detectives, they met on SeekingArrangement.com, where users sign up to be "Sugar Babies" or "Sugar Daddies" in search of "mutually beneficial" relationships.

The FBI indicted the founders of MyRedbook on charges of using the Internet to facilitate prostitution and on multiple charges of money laundering.

Bay Area sex workers say high-powered tech executives likely joked about MyRedbook, which had kind a 1990's-era website look to it.

"I'm sure that they had all kinds of technological critiques of the actual website -- but they were definitely using it," Holloway said.

Another prostitute, who asked that her name not be used, says she has a roster of regular clients from major tech companies. She is a high-end prostitute and estimates that she's made nearly $1 million over the 10 years that she's been working in the area.

She says that her clients are increasingly worried about their own security, which is one of the reasons they have been coming back to her so consistently -- they know what they're getting.