Start by asking yourself how humans have established that a given food, genetically engineered or not, is long-term safe?
As far as I'm aware this angle is FUD.
If we want to apply the same standard to pesticides I'm not sure any high ground exists. That said, whatever effect they have on mortality appears to be miniscule given the trends over the last century.
If we consider this in the context of GMO it sure seems like FUD to me.