Mosquito Dunks can be harmful

if you live in europe they add toxins to your BTI, because i dunno why an europe law forbid to use pure BTI in agricolture without a special permission of your local national agency for agricolture.

All BTI sold on the shelf in europe is "NOT FOR AGRICOLTURAL USE".

You are worring too much. Actually they may be harmful but not so serious as you image. You can find some tips here if you are really worried about the mosquito and other insects. http://topmosquitokiller.com/choosing-the-best-indoor-mosquito-killer-for-your-home/