Heavy metal contamination in cosmetic hair dyes, dermal health risk assessment, and in vivo toxicological implications among exposed women in Khartoum, Sudan

Cosmetic hair dyes can expose users to heavy metals, but integrated evidence combining product contamination, biomonitoring, and dermal risk assessment remains limited in Sudan. We quantified Cu, Cd, Hg, Pb, Mn, and Ni in eleven commercial black hair dyes using validated flame atomic absorption spec