water with hydrogen peroxide and water, 1/4. It will kill the larvae in the soil. Any house plants that you buy, treat before you bring them in. It will take a few cycles to get rid of the gnats.
It the days of DDT farm workers worn no protective clothing either, and died young in droves. Big business is allowed to flourish claiming safety, and it is up to you to prove harm against their team of lawyers.. It took 50 or more years to prove cigarettes cause cancer, low birth weight in...