The U.S. Food and Drug Administration (FDA) announced in a June 15, 2016, Federal Register notice that it had filed a petition on May 16 that the Styrene Information and Research Center (SIRC) submitted to the Agency requesting that 21 C.F.R. § 172.515 be amended to no longer permit the use of styrene as a synthetic flavoring substance and adjuvant in food because these uses have been permanently abandoned. In support of the petition, SIRC provided the results of a survey of its membership, which capture over 95% of the North American styrene industry.  Through this survey, SIRC verified that none of its members:

• Currently manufacture styrene for use as a synthetic flavoring substance and adjuvant in food in the United States;
• Currently import styrene for use as a synthetic flavoring substance and adjuvant in food into the United States;
• Intend to manufacture or import styrene for use as a synthetic flavoring substance and adjuvant in food in the United States in the future; and
• Currently maintain any inventory of styrene for sale or distribution into commerce that is intended to be marketed for use as a synthetic flavoring substance and adjuvant in food in the United States.

FDA requested comments by August 15 on whether these uses of styrene have been completely abandoned, adding that the Agency will not consider any comments on the safety of styrene for these uses since that information is not relevant to abandonment. In January 2016, several nongovernment organizations (NGOs) proposed that the regulations be amended to remove the clearances for styrene and six other synthetic flavoring substances and adjuvants based on data demonstrating the carcinogenicity of the substances.