A molecule composed of four atoms accounts for the almost 188 years of conservation of the heart of d. Pedro 1º, died on September 24, 1834 as a result of tuberculosis. The organ, received in Brazil on Monday (22) in a ceremony like those organized for heads of state, is immersed in a solution of methane (H2CO) and water, the famous formaldehyde.
“It’s not magic, it’s formaldehyde in a closed container, which prevents contact with the external environment”, says Luís Otávio Carvalho de Moraes, professor of anatomy at Unifesp (Federal University of São Paulo).
In the case of the emperor’s heart, the container is a glass support that, traditionally, is locked with five keys in the Church of Lapa, in the city of Porto, in Portugal. The organ was brought to Brazil for the celebrations of 200 years of Independence and will return to Portuguese soil on September 8.
Formaldehyde is used for its ability to prevent the destruction of cells and tissues. As soon as the individual dies or a tissue fragment is removed from a living individual, the process of cellular respiration ceases, starting a process that leads to the destruction of the cell and the tissue it composes, as explained by Professor Silvia Lacchini, coordinator of the Museum of Human Anatomy Prof. Alfonso Bovero, from USP (University of São Paulo).
“To stop or prevent this process, it is necessary to use some type of fixative, and the best known and most used is formaldehyde. As it is able to enter the cell and bind to proteins, changing its structure, it performs a process called coagulation or denaturation, preventing autolysis [destruição celular]”, adds the teacher.
In addition, formaldehyde has an effect on microorganisms, preventing its action on tissue decomposition. It, however, cannot guarantee the maintenance of certain characteristics of the material. “Organs will never have their original color before death because there is no blood circulation, oxygenation, food”, comments Unifesp professor Sergio Ricardo Marques.
In order to maintain the preservation capacity, the professors explain that the solution needs to be changed periodically. In the case of the Museum of Human Anatomy Prof. Dr. Renato Locchi, from Unifesp, Moraes says that the replacement takes place every six months or annually, taking advantage of the opportunity to clean the glass and acrylic containers in which the pieces are exposed. On these occasions, the team uses water, soap and sometimes alcohol.
Before deposition of the organ in the recipient, however, a technique consisting of the injection of formaldehyde is performed. “When the corpse arrives, we first fix it with formaldehyde. All the blood is removed and formalin is injected through the femoral route. He spends hours in this fixation process and, if an organ is to be removed, we also inject formaldehyde directly in that organ. After that, we put this material in a closed container”, details Moraes.
He points out, however, that it is not possible to guarantee that this was the process in d. Peter 1st. As the exclusive use of formaldehyde in the preservation of bodies was described in 1859 —25 years after the emperor’s death —, it is possible that the fixation was carried out with a mixture with another substance. “The culture of preserving bodies is something very old in human history, the method is changing”, he explains.
