Pesticides.

Do you use RoundUp? Maybe you don't but it's likely your neighbors do... Its sold in stores all over the US, so its safe, right? Eh, not so much! Did you know that RoundUp, or glyphosate, is a probable human carcinogen, has been linked to hormone disruption, antibiotics resistance, and other adverse health effects, and it has been found in water sources across the U.S. There are many pesticides used on our yards and on farms in the that aren't safe - many are banned in other countries, but are approved for usage in the US.

Read the article below for a list of pesticides that are currently being reviews by the EPA.

http://civileats.com/2017/02/02/as-trumps-epa-takes-shape-heres-your-pesticide-cheat-sheet/