you can if you have the long and lat, eg ne12596 se 23885 these are the sat positions of the warnings...
i get them on the road just out of mine and there not speed cams but places where they set up mobile cams and also where they sit with lasers hanging out of the cars,
not all woarnings are speeds cameras, some are just speed warnings as sometimes the above may be there.
but you can delete them, im sure you can do it in the poi section of garmin i3 if not the files you downloaded open them in notepad or whatever find the ones you dont want and delete with notepad then resend to your garmin.
i just leave all mine on as sometimes i forget about the sly dogs hiding with the lasers near me.