Splenic Toxicity and Gene Expression Alterations Induced by Perfluorobutanesulfonic Acid (PFBS) Ingestion in Sprague Dawley Rats.

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are synthetic chemicals widely used in industrial and consumer products. Chronic exposure to PFAS has been associated with adverse health outcomes, including kidney cancer, thyroid dysfunction, pregnancy complications, and liver damage. This study investigates the splenic toxicity of Perfluorobutanesulfonic acid (PFBS), a short-chain PFAS compound composed of a four-carbon backbone bonded to fluorine atoms and a sulfonic acid functional group. PFBS is commonly found in wastewater, household dust, and cleaning agents. To assess its biological impact, Sprague Dawley rats were fed diets containing varying concentrations of PFBS. Histological analysis of the spleen revealed no overt structural damage and molecular profiling indicated significant alterations in gene expression. SYK, a spleen tyrosine kinase protein increased in PFBS exposed groups. A significant increase in the rat weight of exposed groups and marginally inflamed spleens may suggest some effects of PFBS ingestion on the treated animals. Transcripts associated with T-cell regulation and protein phosphorylation were upregulated, while inflammatory and immune-related genes were downregulated. Serum LDH levels showed slight elevation in PFBS-exposed groups, and animals receiving higher doses exhibited increased body weight compared to controls. These findings suggest that dietary ingestion of PFBS induces subtle but measurable toxicological effects on splenic function and immune regulation, probably indicating further research into its long-term health implications.