I’m no climate scientist but I would think it’s similar to toxicity/poisoning. You can die from water intoxication but certainly you need it to live as well. So

I’m no climate scientist but I would think it’s similar to toxicity/poisoning. You can die from water intoxication but certainly you need it to live as well. So no, I don’t think it’s subjective. It seems to me that if something is capable of causing harm in a certain amount, it’s poisonous/pollution/toxic.