However, because the Cry9C protein lingers in animal digestive systems before breaking down, the EPA had concerns about its allergenicity, and PGS did not provide sufficient data to prove that Cry9C was not allergenic.[6]: 3 As a result, PGS split its application into separate permits for use in foods intended for human consumption and for use in animal feed only.[2][7] StarLink was approved by the EPA for use in animal feed in May 1998. Following the recalls, PGS at first tried to get the application for human consumption approved, and then withdrew the product entirely from the market.[4]: 15