Can a tannic acid-based solution substitute formalin as a fixative for macroscopic specimens?

  • Rafael Cisne de Paula Department of Morphology, Biomedical Center, Fluminense Federal University, Niteroi, Rio de Janeiro, Brazil
  • Alessandra Mendonça Teles Souza Laboratory of Molecular Modeling and QSAR (ModMolQSAR), Center for Health Sciences, Faculty of Pharmacy, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
  • Marco Aurélio Pereira-Sampaio Morphology Department, Fluminense Federal University, Niterói, Rio de Janeiro, Brazil.
  • Silvana Lima Gorniak Research Center for Veterinary Toxicology (CEPTOX), Department of Pathology, School of Veterinary Medicine, University of São Paulo, São Paulo, Brazil
  • Paula Carvalho Papa Department of Surgery, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo, Brazil.
  • Marcio Antonio Babinski Morphology Department, Fluminense Federal University, Niterói, Rio de Janeiro, Brazil.
Keywords: alternative solution, dissection, formaldehyde, tannic acid, toxicity

Abstract

Introduction: The most famous pedagogic tool to teach anatomy is the dissection. Despite recent models with fresh cadavers, dissection mainly occurs in formalin fixed specimens. However, this substance is known to be toxic. Several alternative solutions appeared in the last decades, although most of them are used in microscopic studies, as such, the macroscopic environment remains in need of a new alternative capable to replace the formaldehyde. The study conducted herein proposes the use of this solution as an option for formaldehyde replacement. Material and Methods: 8 Wistar rats were fixated in a 10% formalin solution and 8 rats were fixated in a tannic acid alcohol-based solution (0.25%). These animals were dissected by 14 medical students. Afterwards, the students received a questionnaire to evaluate aspects such as odor, texture and color of the specimen and flexibility of the joints.  The toxicity of each compound was analyzed by “in silico” tests for cutaneous and respiratory systems. Results: The results showed superiority of the tannic acid alcoholic solution over the regular formalin solution in several parameters analyzed, except in relation to the color of the specimen. The toxicity of skin and respiratory tract was absent in tannic acid alcoholic solution.  Conclusion: The tannic acid may be a substitute to formaldehyde-based solutions, as it has been show to decrease risk factors to individuals that manipulates fixed corpses and tissues.

Published
2020-03-31
How to Cite
de Paula, R., Souza, A., Pereira-Sampaio, M. A., Gorniak, S., Papa, P., & Babinski, M. (2020). Can a tannic acid-based solution substitute formalin as a fixative for macroscopic specimens?. Acta Scientiae Anatomica, 1(4), 213-220. Retrieved from http://actasanatomica.com/journal/index.php/asa/article/view/80
Section
Artigos