In chapter 27, the narrator states that the six Kanka-bono orphan girls' parents were killed by insecticides sprayed from the air in the Ecuadorian rainforest. My initial connection to this information was the excessive use of pesticides in the modern world, especially in fertile, under-regulated regions in South America. Synthetic pesticides are toxic to humans, resulting in birth defects and even death. It is notable that 99% of pesticide related deaths occur in developing countries, such as Ecuador where our story takes place.
Also, I recalled that Vonnegut was vehemently against the Vietnam War. The United States used copious amounts of Agent Orange, a highly concentrated herbicide meant to defoliate the Vietnam rainforest. Agent Orange is a lethal chemical substance not only for the environment, but for humans as well. The Vietnam Red Cross has recorded roughly 4.8 million deaths and over 400,000 children born with birth defects due to Agent Orange exposure. When Galapagos was published in 1985, the citizens of Vietnam were still coping with the effects of the war, especially the damage done by Agent Orange.
Vonnegut seems to have added this instance of insecticide-related death as homage to the similar cases in Vietnam.
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