It is notable that pesticides came about as a result of he development of using toxic gas as weapons against people during World War I. Almost all pesticides will affect some people in a negative way. Short term risks are mostly negligible. However over the long term affects can be cumulative.

@snytiger6
Gerhard Schrader (25 February 1903 – 10 April 1990) was a German chemist specializing in the discovery of new insecticides, hoping to make progress in the fight against hunger in the world. Schrader is best known for his accidental discovery of nerve agents such as sarin and tabun, and for this he is sometimes called the "father of the nerve agents".[1]
Schrader discovered several very effective insecticides, including bladan (the first fully synthetic contact insecticide), and parathion (E 605). In 1936, while employed by the large German conglomerate IG Farben, he was experimenting with a class of compounds called organophosphates, which killed insects by interrupting their nervous systems. Instead of a new insecticide, he accidentally discovered tabun, an enormously toxic organophosphate compound and nerve agent. During World War II, under the Nazi regime, teams led by Schrader discovered two more organophosphate nerve agents, and a fourth after the war: