Food emulsifiers increase toxicity of food contaminants in three human GI tract cell lines

Food products simultaneously containing both food contaminants and emulsifiers are common in baked products, coffee and chocolate. Little is known regarding how food contaminants and emulsifiers interact and alter toxicity. Recent studies have shown that while emulsifiers themselves have little toxicity, they could cause changes in the gut microenvironment and lead to issues such as increased uptake of allergens. This study examined toxic effect of two common process contaminants acrylamide (AA) and benzo [a]pyrene (BAP) combined with food emulsifiers polyoxyethylene sorbitan monooleate (TW) or glycerol monostearate (G). In liver cell line HepG2 and gastrointestinal cell lines HIEC6 and Caco-2, toxicities of AA and BAP were increased by TW but not by G as indicated by decrease in IC50 values. Addition of TW also exacerbated gene expression changes caused by AA or BAP. Cellular uptake and cell membrane permeability were enhanced by TW but not by G, but tight junction proteins of Caco-2 monolayer was impacted by both emulsifiers. These results suggested that TW could increase toxicity of AA and BAP through increasing cell permeability thus chemical uptake and potentially through other interactions. The study is to draw the attention of regulators on the potential synergistic interaction of co-occurring chemicals in food.