Benzenamine, N-phenyl-, reaction products with styrene and 2,4,4-trimethylpentene (BNST) is an antioxidant used as an additive in many industrial lubricants. Its use has been restricted in Canada under the Prohibition of Certain Toxic Substances Regulations, 2012, which went into effect on March 14, 2013. The Regulations include a two-year exemption for BNST used in small-application lubricants in the electrical and electronics engineering industry.