The researchers indicate that the ancient Egyptians synthesized various forms of black eye makeup using two non-natural lead chlorides—laurionite and phosgenite. According to Egyptian manuscripts, these compounds provided some sort of a “magical/spiritual” effect that helped protect against ocular disease and skin infection.
Drawing from existing data, the researchers suggest that the lead-based substances found in ancient Egyptian eye makeup boosted the normal production of nitric oxide in human skin by 240%.
Nitric oxide is a key signaling agent in the human body, and can boost an individual’s immune system to help fight disease.
Because eye infections caused by bacteria were likely prevalent in the Nile River Valley following floods, the researchers believe that ancient Egyptian “chemists” may have deliberately formulated these lead-based cosmetics to prevent and combat potential disease.
“One cannot evidently go as far as to propose that laurionite was purposely introduced into the composition of the makeup because of any recognized antibacterial properties,” say the researchers. “Yet, one can presume that ancient Egyptian ‘chemists’ recognized empirically that whenever this ‘white precipitate’ was present in the makeup paste, their bearers were enjoying better health, and thus decided to amplify this empirical protective function by specially manufacturing laurionite.”
“Whether or not the manufacture of these lead chlorides was deliberately connected to preventative health care by Egyptians, it is clear that such intentional production remains the first known example of a large-scale chemical process,” add the researchers.
Tapsoba I, Arbault S, Walter P, Amatore C. Finding out Egyptian gods’ secret using analytical chemistry: biomedical properties of Egyptian black makeup revealed by amperometry at single cells. Anal Chem. 2010 Jan 15;82(2):457-60.