Quaternium-15, a preservative, is one of the most used substances and is added to several cosmetics and other industrial products. Quaternium-15 is a mixture of isomers, where the cis-form is the dominant form and where the trans-form is the minor component present as an impurity. Quaternium-15 can be found under a variety of names, most commonly those of the Dow Chemical Company: Dowicil 200 (cis isomer only), Dowicil 75 and Dowicil 100 (both a mix of cis and trans isomers). The isolated cis-compound is used primarily in cosmetic applications, with a maximum permitted concentration in the EU of 0.2%. DOWICIL 200 preservative (cis form) is used primarily as a preservative in a wide variety of personal-care and cosmetic products. It is designed to provide highly effective broad-spectrum antimicrobial activity, especially in water-based formulations. It is used in both leave-on and rinse-off application such as baby-care products, hair-care products, lotions, powders, and creams. The mixed product (cis- and trans-) is used in a wider range of formulations such as: emulsifiable metal-cutting fluids; latex and emulsion paints; liquid floor polishes and floor waxes; glues and adhesives. Recently, the cis-form has been classified as a CMR substance with the classification toxic to reproduction, category 3. This classification only concerns the cis-isomer:

alpha-Amyl cinnamaldehyde is a pale yellow liquid fragrance material with a floral smell used in allergenic testing.

Diazolidinylurea is a broad-spectrum antimicrobial preservative used in cosmetics and pharmaceutical preparations. It is especially active against gram-negative bacteria and is often combined with parabens. Diazolidinylurea is the most active member of the imidazolidinyl urea group, that acts as a formaldehyde releasers. Diazolidinylurea is used in many cosmetics, skin care products, shampoos, and conditioners, as well as a wide range of products including bubble baths, baby wipes, and household detergents.