My LO is intolerant to salicylates and gets mucus poos from them. Apples contain "high" amounts, peas contain "moderate" amounts. Carrots and sweet potatoes contain moderate amounts. My LO can't tolerate moderates yet, only "lows"
Basically, low salicylate fruits and veges are ripe peeled pears , peeled white potatoes, mung beans, bean sprouts, brussel sprouts, cabbage, celery.
Stone fruits, citrus, berries are "high" to "very high", which contain 10 and 100 times the amount of salicylates found in "low" foods.
I can point you to information about following a low salicylate diet if interested, just let me know.