Anatomo-comparative study of formaldehyde, alcohol, and saturated salt solution as fixatives in Wistar rat brains.

Although formaldehyde is the most widely used and largely available fixative for preserving cadavers through decomposition prevention, it promotes darkening and weight gain, in addition to being considered carcinogenic. Ethyl alcohol has been proven a potential substitute to formaldehyde due to its effectiveness in tissue penetration, thus preventing proliferation of microorganisms; however, it can only be used alone for fixation of small parts. In view of such fixatives limitations, saturated salt solution has been widely employed based on its antimicrobial effect and ability to maintain tissue similar to the original one, in addition to exerting no hazardous effects as there is no evaporation of harmful substances.