Studies supporting the low dose theory have repeatedly been judged by independent regulators as unreliable for use in human risk assessment. None of the studies claiming such effects could be reproduced by other scientist teams. Several comprehensive studies that also investigated the question of potential effects of very small levels of BPA on the metabolism and looked at several generations, did not find any such effect. However, numerous studies show that the level of migration, if any, is far below any safety-based standards set by government bodies such as the European Food Safety Authority (EFSA) or the U.S. Food and Drug Administration (FDA), and such exposure poses no known health risk. The low dose theory has repeatedly been judged by independent regulators as both unreliable and unconvincing.