Dimethyloldimethyl hydantoin is a popular preservative with moderate sensitizing potential, it is used to control against mold, mildew, and bacterial spoilage. This preservative is similar to imidazolidinyl urea, as both act by releasing formaldehyde into the formulation. Cosmetic expert panels have determined that Dimethyloldimethyl hydantoin has an excellent safety record for use in both leave-on and washoff cosmetic preparations. Maximum-use concentrations are set at 0.2 percent in the u.S. and 0.6 percent in the european union. Dimethyloldimethyl hydantoin stands for dimethylimidazolidine, though in a listing the acronym is rarely spelled out.
