In what ways have pesticide technology has good and bad impacts?

It kills insects,

Pros: less annoying weeds.

all the rodents and insects eating your crops will die

estimations show that millions of human lives have been saved from it (because bugs that carry malaria or yellow fever, or the black plague are being killed

Cons: Rodents and insects are very beneficial to the environment, so killing them harms the environment

the weeds and insects will become immune