The copper complex has stability characteristics that depend on the formulation environment, and a formulation outside the appropriate pH range can affect the integrity of the copper complex over the formulations shelf life
de Jong M, van der Worp HB, van der Graaf Y, Visseren FLJ, Westerink J
And ruminococcus torques in feces of children with autism spectrum disorder
To understand why skincare has limits here, you have to look at what happens beneath the surface
Hg exposure levels even at low concentrations (1.0 and 1.5 mg/L) can be toxic for plants that lead to disruption of cellular function, plant growth, and development [30]
So why consider copper peptides