Amorphous fumed silica, nano - 112945-52-5

Key Functions: Food Contact & Additives

Due to the overlap in CAS numbers (for example SAS, Amorphous silica, and Crystalline silica all share a CASRN of 7631-86-9), studies were only included if the use of fumed SAS is explicitly stated. Another exception lays in E551, an authorized food additive for use as an anticaking agent and carrier. It may include fumed silica, but only studies explicitly stating the presence of fumed SAS are included in the assessment. Primary particles of fumed nanosilica typically fall in the range of 2-50 nm in diameter, but nanosilica has a tendency to form aggregations which then can agglomerate into particles around 694 μm in diameter (Cab-O-Sil)(De Temmerman et al., 2012). 1 In the case of synthetic amorphous silica, biological activity is related to the particle shape and surface characteristics more so than to particle size or mass, since the SAS adsorbs to cellular surfaces and can affect membrane structures and integrity (Akbar, Mohamed, Whitehead, & Azzawi, 2011; Fruijtier-Pölloth, 2012)

Chemical Synonyms fumed (or pyrogenic) nanosilica, a synthetic amorphous silica (SAS) prepared by thermal or pyrogenic methods

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