John Haigh believed he had concocted the "perfect murder," until forensic science caught up to him in 1949 Sean Neumann is a reporter at PEOPLE. He has been working at PEOPLE since 2019.

Glycolic acid is a substance that chemically exfoliates a person’s skin by dissolving dead skin cells and oils. Glycolic acid may also help boost collagen production, and support skin moisture.

Creative Commons (CC): This is a Creative Commons license. Attribution (BY): Credit must be given to the creator. The ability to distinguish scents, volatile organic compounds (VOCs), and their ...

Department of Chemistry, University of York, York YO10 5DD, U.K.