As others have pointed out, DDT is still in use for vector control, however its effectiveness is reduced because of resistance caused by excessive use for agricultural and general pesticide purposes.
Mosquito resistance to DDT was something that was noted in the years before the effects on birds were raised, and this had as much to do with the ban on agricultural use as the ecological issues.
DDT use really was out of control in the post-war period[1] and I think it is hard to say how severe the effects of a biopersistent chemical would be when its use was just increasing, increasing and increasing with no end in sight.
Mosquito resistance to DDT was something that was noted in the years before the effects on birds were raised, and this had as much to do with the ban on agricultural use as the ecological issues.
DDT use really was out of control in the post-war period[1] and I think it is hard to say how severe the effects of a biopersistent chemical would be when its use was just increasing, increasing and increasing with no end in sight.
[1]http://www.youtube.com/watch?v=-UiCSvQvVys