I don't think you can link everything which goes up with something which goes down.
What is the background radiation and what was the background radiation? What has happened to the UV radiation? What food additives are on the increase in France?
I would suspect there may be more deformed sperm rather than fewer sperm as the result of radiation, but I don't know. And I'd suspect something in the diet more than in the air.
But that's just me.