Is it possible to tell or rule out (potentially a priori) whether any given substance or compound is likely and how likely to cause allergies with high confidence, without the need to conduct experiments, e.g. by looking at its properties, e.g. solubility, molecular structure or reactivity?
From what I've heard is that generally speaking, things that we come in contact with in early years tend to be less likely to cause problems later on, but still, there seem to be differences even with food and substances that do not quite appear to be exotic, e.g. peanuts.
This question is related to these, though I'd consider it more generic.