Assuming the apples are fresh and clean, there is no real risk of toxicity associated with feeding them. (petconsider.com)
Also certain vitamins and minerals can be dangerous at high levels, so it's possible that consuming large amounts of these products could put a person at risk of toxicity. (whatreallybuildsmuscle.com)
For healthy people with normal kidney function, there is not any known risk of toxicity from excessive dietary potassium under any circumstance. (whfoods.com)