All the arguments presented by the Environmental Defense Fund responsible for getting DDT banned during the hearings in the summer of 1972 were ultimately debunked by the independent studies done by the Fish and Wildlife service.
Then EPA director, William Ruckelshaus, who never attended one of the hearings, just arbitrarily banned it. Apparently he had personal ties to the EDF.
The claim that DDT caused the thinning of birds' eggs was a lie and subsequent studies by the Fish Wild. dept. proved just the opposite. It the test studies done on pheasant and quail eggs, the birds that were fed a steady diet of DDT had a hatch rate of approx. 80% while the other test group that wasn't fed DDT only had a hatch rate of around 53%
Another lie was that DDT was responsible for the decline in the bald eagle. The reality was the loss of habitat and hunter predation on not only the eagles but all other raptors as well. In fact, Alaska offered a bounty on bald eagles between 1917 and 1953 in order to protect the salmon industry.
Junkscience has a great article at their site detailing all that happened during those hearings.
It WAS overused, they were using it for EVERYTHING, which...I don’t blame them a bit. If I had been a farmer, rancher, or someone combatting insect populations, I darn well would have overused it. Heck, they used to dust people with it!
Once I investigated it this whole scam (not just accepting what I had been taught over the years, heard via the media or government, etc.) I never bought into the eggshell thinning part of it, or the toxicity part, etc.
But I did feel that the overuse of it had real potential for creating a resistance to it in some of the insect populations we were using it on. Over time, that can be a real problem with many insecticides that are overused.
But that wasn’t the main reason it was banned in favor or more expensive and more toxic insecticides, as you point out.
Funny, my buddy and I occasionally drive up in Maine, and when we pass the sign for the “Rachel Carson Wildlife Area” he says “Hand Salute!” and we both extend our middle finger to it1