An online version of a UK newspaper reports that several parents have become concerned about the appearance of mold in a machine designed to mix formula quickly. Some mothers have complained that despite their cleaning, the machine has developed black matter that has made their children sick. They showed videos and photos of the contamination. The machine costs up to 120 pounds and is supposed to prepare formula in two minutes. The company claims the black matter is harmless carbon and not mold. It also said the parents are using the wrong filters.