Histological Changes in the Cerebellum of Albino Rats after Inhalational Exposure to Pyrethroid Based Mosquito Repellent
Background: There has been an ever increasing use of liquid vaporizers as residential insecticides to get rid of the problem of mosquito and as a concern shown towards prevention of increasing cases of vector borne diseases. Adverse impact of these chemicals are many including giddiness, nausea, headache, body ache, lethargy and dizziness but the current research on the safety of these chemical compounds is market driven and proper histological studies that can establish their toxic effects on cerebellar cortex which acts as higher centre of coordination, balance and learning are rare. Accordingly the present study was planned to look into the claim of safety of these inhalational compounds and to establish the correlation, if any between pyrethroid based mosquito repellent inhalational use and the histological insult to the cerebellum of Albino rats. Methods: Total of twenty albino rats were marked into groups marked as control and experimental. The exposure of experimental group was carried out to 3.2% w/v prallethrin vapours for total of 12 hours in a day and continued for 180 days. The Albino rats in control group were put in similar surroundings but without exposure to any mosquito repellent. The albino rats were killed after completing exposure of 180 days. The rats brain was dissected and Cerebellum was taken out. Tissue processing and sectioning done and finally stained wusing haematoxylin, eosin and thionin stains. Results: Outer molecular and inner granular layer of cerebellum showed areas of degeneration with disruption and decreased density of cells in Purkinje cell layer. Conclusions: The findings of the study do confirms that mosquito repellents given by inhalational route leads to toxic insult as evident in this study on Albino rats on long term exposure of 180 days as shown by histological alterations in the sections of cerebellar cortex of rat CNS.
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