Some individuals have concerns regarding the adjuvants and preservatives used in vaccines. Adjuvants are added to enhance the immune response, while preservatives extend shelf life. The acellular pertussis vaccine commonly uses aluminum salts as adjuvants, which are regulated substances deemed safe at the concentrations used in vaccines. Thimerosal, a mercury-based preservative, is not used in most pediatric vaccines, including DTaP. Regulatory bodies, such as the FDA and WHO, conduct rigorous evaluations to ensure these components are safe for human use.
