I always wanted to write about the parabens compounds. Not only they have sparked my chemical interest but also caused an alert when buying cosmetics, food and even pharmaceutical preparations.
Chemically speaking, they are esters of para-hydroxybenzoic acid, commonly known as parabens. Among them, it stands out the methylparabens (e2189), propylparabeno (E216) or the butylparabeno. Thus, the difference between them depends on the alkyl group (R in the figure). These are used as broad spectrum preservatives because they have antibacterial and antifungal properties and therefore destroy germs that can grow in the environment, such as those containing oil and water.