You're just grasping at straws. The French would not let the Eiffel Tower get damaged like that, they would repair it immediately, if the damage was localised only to Paris.
And if it was a Chernobyl event, then why did the Betty land there? Surely they would have known. May as well land in Fukushima or Chernobyl if they're going to do that.
Another reason why Paris is post-apocalypse is because of
Delicatessen, another film by Jeunet, because Paris was not in the script by Joss Whedon.
Post-apocalyptic France in Delicatessen: