It has long been a source of amusement for me to see some cosmetic brands market that they are "chirally correct".

Every cosmetic brand  uses chirally correct forms of cosmetic ingredients. I would challenge any "chirally correct" marketer to show me a cosmetic product that does not contain the "chirally correct" form of an ingredient. I'll be waiting a long time.

Some chemicals have two different forms, or enantiomers, which are a mirror image of each other. These forms are named according to the direction light passed through them is turned: Levo (left) or Dextro (right). Thus, there is L-lactic acid, L-ascorbic acid and L-retinol.

The point that these "chirally correct" cosmetic marketers don't point out is that cosmetic ingredient suppliers only supply chirally correct forms of ingredients for use in cosmetics. In the case of L-ascorbic acid there is no "D-ascorbic acid"; the D form of ascorbic acid is termed erythorbic acid.

Claiming cosmetics are "chirally correct" is analogous to claiming a car has four wheels. So what? Either marketers of "chirally correct" cosmetics are incredibly ignorant or incredibly manipulative.