I was on a BA flight about 10 years ago from Boston to LHR where we were told there would be no nuts served with our pre dinner drinks due to a child, back in the rear of the plane having a nut allergy. I was a little surprised that the child had survived to that age if he or she suffered such a reaction from presumably airborne particles causing distress, as nuts as we all know are used in all manor of products so exposure must be comonplace. I can understand the airline being made aware of the issue, and wanting to ensure a situation was not caused which may have led to divert or worse, but can not help but feel this must have been overly pushed. My normal regular carrier EK present you with a bowel of warmed mixed nuts on every flight with pre dinner drinks as I believe AA do as well, and I have never heard of a nut allergy situation when these have not been handed out.
Kind regards
Mr Mac