Rachel Carson was full of it. That has been well documented. Because of her nonsense being touted as truth, millions of people died from malaria who might have been spared had DDT not been banned. We used to ride our bikes through clouds of the stuff while we followed the billowing mosquito spray truck down the street. No issues so far.
They were still issuing a can of the powdered stuff when I was in the Army. Can't imagine why the issued it tho......