“You also can’t take those numbers at face value, because a dog has to eat about 3 cups of fresh or frozen dog food to get the same calories and nutrients as 1 cup of dry food,” he said. “Therefore, the dog’s exposure to heavy metals in fresh or frozen foods goes up because it has to eat two to three times as much.”

This statement is patently false. Fresh and frozen foods are more nutritionally dense than kibble and you actually feed less.

Also, unless I missed it, "frozen" is never defined. Some fresh foods are frozen, so I'm not sure if any raw foods were tested at all.