For several decades, food-grade synthetic amorphous silica (SAS) have been used as a technological additive to reduce caking of food powders. Human exposure is thus inevitable and safety concerns are taken seriously. The toxicity of silica in general and SAS in particular has been studied extensively. Overall, there is little evidence that food-grade SAS pose any health risks to humans. However, from the available data it was often not clear which type of silica was used. Accordingly, the latest report of the European food safety authority requested additional toxicity data for well-characterised “real food-grade SAS”.

To close this gap, we screened a panel of ten well-defined, food-grade SAS for potential adverse effects on differentiated Caco-2 cells. Precipitated and fumed SAS with low, intermediate and high specific surface area were included to determine structure-activity relationships.

In a physiological dose-range up to 50 μg/ml and 48 h of incubation, none of the materials induced adverse effects on differentiated Caco-2 cells. This held true for endpoints of acute cytotoxicity as well as epithelial specific measures of barrier integrity. These results showed that despite considerable differences in production routes and material characteristics, food-relevant SAS did not elicit acute toxicity responses in intestinal epithelial cells.

几十年来，食品级合成无定形二氧化硅（SAS）被用作减少食品粉末结块的技术添加剂。因此，人体暴露是不可避免的，因此必须认真考虑安全问题。二氧化硅的毒性，特别是SAS的毒性已被广泛研究。总体而言，几乎没有证据表明食品级SAS对人类构成任何健康风险。但是，从现有数据来看，通常不清楚使用哪种类型的二氧化硅。因此，欧洲食品安全局的最新报告要求针对特征明确的“真实食品级SAS”提供其他毒性数据。

为了缩小这一差距，我们筛选了一组十种定义明确的食品级SAS，以了解对分化的Caco-2细胞的潜在不良影响。具有低，中和高比表面积的沉淀和气相SAS用于确定结构活性关系。

在高达50μg/ ml的生理剂量范围和48 h的孵育时间中，没有一种物质对分化的Caco-2细胞产生不利影响。对于急性细胞毒性的终点以及屏障完整性的上皮特异性测量，这都是正确的。这些结果表明，尽管生产途径和材料特性存在显着差异，但与食品相关的SAS并未在肠道上皮细胞中引起急性毒性反应。