SODIUM BENZOATE-MEDIATED CYTOTOXICITY IN MAMMALIAN CELLS

Sodium benzoate (SB) is widely used in food chemistry, cosmetics and the pharmaceutical industry. Previous studies suggest possible toxic effects of SB when used as a food preservative. However, these studies were confined to microbiological systems. Therefore, we investigated the cytotoxic effects of SB in rat-cultured cortical neurons and in human clonal epithelial cells (HeLa cells) using cell death assays and the fluorescent measurements of intracellular Ca2+ concentration ([Ca2+](i)) and mitochondrial transmembrane potential (Delta psi(m)). We found that SB induced cell death in a dose-dependent manner. Even 0.1% (w/v) SB, a concentration typically added to soft drinks, produced a significant decrease in cell viability in rat cortical and HeLa cells. We also found that SB caused [Ca2+](i) and Delta psi(m) increases in a dose-dependent manner. Based on our results, more caution and further cellular studies are required with respect to the use of SB as a food preservative.