Both federal agencies declined to comment.
The FTC has already shown that privacy and security issues tied to the Internet of Things are on its radar. In January, the agency recommended a set of best practices for companies, in a 71-page report calling on companies to take steps to prevent unauthorized use of consumers' data.
At the Consumer Electronics Show in Las Vegas in January, FTC Chairwoman Edith Ramirez expressed her concerns over the risks of hacking tied to Internet connected devices.
On Friday, a spokeswoman for Nest declined to comment on EPIC's letter.
A spokeswoman for Samsung said the group's claims do not reflect the actual features of the company's Smart TV. Voice recognition, which allows users to control the TV using voice commands, is a feature that can be deactivated by the user, she said.
Google, Microsoft, Amazon and Mattel did not immediately respond to requests for comment.
A spokeswoman for home camera maker Canary Connect said the group's concerns are worth serious discussion. The company's security system has controls to let users know when recording is taking place, she said, including a privacy mode that turns off video and audio recording when users are home.
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