Raw onions are perfectly safe to eat and are not toxic.
I like to snack on raw onions everyday and It's never made me sick.
But some people may have an intolerance to onions which could cause stomach pains or bloating and gas pains or gas.
If you're experiencing stomach problems or any of the above symptoms then you likely have an intolerance to onions and should speak to a doctor about it.
Otherwise onions are very healthy for you and are an antioxidant which is good for removing toxins from your body.