I've talked about organic agriculture before, so I'll cut to the chase:
We found that in addition to reduced efficacy against aphids compared to novel synthetic insecticides, organic approved insecticides had a similar or even greater negative impact on several natural enemy species in lab studies, were more detrimental to biological control organisms in field experiments, and had higher Environmental Impact Quotients at field use rates.
If you want the CliffsNotes version, you can read about it in the CBC article that originally caught my eye. The full text is available online for free.
It's just one study, sure. One more study. There have been many. There will be many in the future. I think this lovely and eloquent quotation from one of my favourite science enthusiasts about sums it up:
Science. It works, bitches.