PEG-40 Sorbitan Stearate
Cosmetic Ingredients Series
PEG-40 Sorbitan Stearate is a synthetic compound, a fatty acid ester with many variations. Esters help to reduce surface tension between liquids and so are frequently used as emulsifiers and surfactants . You'll find them in Nivea moisturising creams for example.
The LD50 is the Lethal Dose in 50% of the population. It is used as the basis for calculating how safe a chemical is for subsequent use in products such as food, cosmetics, colourants and medicines. It is normally calibrated using animal testing.