[Edit] The below comment is inaccurate. The pesticide sprayed for gypsy moths was DDT. I am leaving this comment because it should be known that this was a thing even though it is now off topic.

P̵a̵r̵a̵q̵u̵a̵t̵ DDT is also linked to the polio pandemic. It was sprayed everywhere gypsy moths were found. Great success at killing moths. Also weakened human children to to where a common disease could get into spines and cause paralysis.

Researching this kind of stuff is not for the faint of heart. Its horrible all the way down. Not recommended for the faint of heart.