(Nitrilotriacetic acid) This carcinogenic phosphate substitute is banned in the U.S. As with EDTA, it can free heavy metals in the environment and reintroduce them into the food chain. NTA is slow to biodegrade. Found in: No U.S. manufactured products. However, imported products, especially laundry detergents, should be scrutinized to ensure that no NTA has escaped regulatory attention.