The effect of repeated exposure to formaldehyde on learning, spatial memory and anxiety-like and obsessive behaviors in the rat animal model

Formaldehyde is a volatile organic substance that is widely used in industry and medicine. According to some studies, formaldehyde has the ability to enter the brain and can lead to neurological complications and disorders related to memory and learning. Some studies have also shown that formaldehyde plays a role in the process of Alzheimer's disease. The aim of this study was to investigate the effect of formaldehyde on spatial memory, anxiety and obsession in rats. For this purpose, 24 adult Wistar rats were divided into four groups including: 1- control group, 2- group receiving formaldehyde in the amount of 1 ppm, 3-group receiving formaldehyde in the amount of 2 ppm, and 4- group receiving formaldehyde in the amount of 3 ppm. The treated groups were exposed to formaldehyde for seven consecutive days and six hours a day. After the completion of the exposure period and the training and training courses, Open Field and Morris water maze behavioral tests were performed and the data were recorded and analyzed. In the Morris water maze test, with increasing formaldehyde dosage, the time to reach the hidden platform and the amount of presence in the opposite quadrant of the platform increased, and the duration of presence in the SE section and the number of times to enter it decreased. In the Open Field test, exposure to formaldehyde caused a significant increase in the number of crossing lines and grooming behavior and a decrease in the lifting movement on the hind legs (P<0.05). According to the findings of the present study, exposure to inhaled formaldehyde can have a destructive effect on memory and learning and can increase anxiety and obsession.