Nitrite, an inorganic compound. Mainly refers to sodium nitrite, which is white to yellowish powder or granular, slightly salty and easily soluble in water. Similar in appearance and taste to salt, it is widely used in industry and architecture, and it is also allowed to be used as a color developer in meat products in limited quantities. The probability of nitrite causing food poisoning is very high. Eating 0.3 ~ 0.5g of nitrite can cause poisoning, and 3g can cause death.