The histopathological effects of formaldehyde on the lung and brain in the rat animal model

Formaldehyde (FA), scientifically known as methanol and known by the chemical formula CH2O, is a colorless, water-soluble gas whose pure form is a stimulant. Due to the high use of formaldehyde in various industries as well as its high ability to fix and maintain body tissues. Formaldehyde directly reacts with tissue components and its cytotoxicity is probably due to its high reactivity. In this study investigate the toxic effects of formaldehyde on people who deal with this substance regularly, such as anatomists, medical students, and workers in various industries. For this study, 24 adult male Wistar rats were divided into four groups of six. Animals had free access to adequate water and food. After the adaptation period, the animals were divided into the following groups: control group: normal saline recipient by inhalation, group one: 1ppm formaldehyde recipient, group 2: 2ppm formaldehyde recipient, group 3: 3ppm formaldehyde recipient. Exposure time was from 8:30 am to 2:30 pm for six hours a day for seven days. At the end of the exposure, lung, and brain tissue sections were taken, stained, and then studied. Blood samples were also taken from the heart to evaluate liver enzymes. The DG region of the cerebral hippocampus sections showed an increasing trend of neuronal necrosis and degenerative changes of neurons in groups 2 and 3 and pathological changes such as leukocyte infiltration, alveolar wall thickness, and vascular congestion in the lung tissue sections were also significant in groups 2 and 3.
The results of this study indicate a direct relationship between increasing the dose of formalin intake and brain, lung, and liver damage