Uptake of calcium and magnesium by human scalp hair from waters of different geographic locations.

The uptake of Ca2+ and Mg2+ by human scalp hair from waters of 24 different locations throughout the world was determined. The uptake was found to vary markedly depending on the initial total hardness and pH of the water. Water of high initial total hardness and/or high initial pH were found, in general, to result in more hair adsorption of these alkaline earth cations. When hair is washed with these differing waters, varying effects are then found in the eventual coiffure.