In one of her fish recipes Delia said to wrap the fish in baking foil. However, I have seen reports online that to cook anything using aluminium foil can lead to long term health risks, as heat can cause aluminium to leach into the food being cooked.
I don't know if this concern is a recent one, or if it has been raised previously. As someone who is trying to learn to cook late in life (I'm 62) such stories make me apprehensive about using foil to cook anything. It would be helpful to know what your team's ideas are on this subject.