It came from a growth promotion drug in feed that has since been suspended by the FDA. In another study, Nachman's team found that some chicken feather meal contain small amounts of the active drugs in Tylenol, Benadryl and Prozac.

它来自于饲料中的一种生长促进药物，后来被FDA暂停使用。在另一项研究中, Nachman的研究小组发现，一些鸡毛粉含有少量的泰诺、苯那君和百忧解的活性药物。