As said above, all these sorts of gadgets are small radio transmitters and receivers that emit harmless rf energy that have to pass strict government standards. Do you really think Amazon. Google, Apple and countless other companies would market harmful rf gadgets? If so, you need to get better educated.
But if a local radio or TV station wanted to erect a powerful transmitting antenna in the vacant lot next to your house, THAT would be a concern Fortunately, the law would not allow it.