AUTHOR=Kim Sung-Hyun , Lee Jin Hee , Jung Kikyung , Yang Jun-Young , Shin Hyo-Sook , Lee Jeong Pyo , Jeong Jayoung , Oh Jae-Ho , Lee Jong Kwon TITLE=Corrigendum: Copper and Cobalt Ions Released From Metal Oxide Nanoparticles Trigger Skin Sensitization JOURNAL=Frontiers in Pharmacology VOLUME=12 YEAR=2021 URL=https://www.frontiersin.org/journals/pharmacology/articles/10.3389/fphar.2021.670581 DOI=10.3389/fphar.2021.670581 ISSN=1663-9812