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.

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.

Department of Pharmaceutical Analysis, School of Pharmacy, China Pharmaceutical University, Nanjing, Jiangsu 210009, China ...