title: TEM and SP-ICP-MS analysis of the release of silver nanoparticles from decoration of pastry.
abstract: Metallic silver is an EU approved food additive referred to as E174. It is generally assumed that silver is only present in bulk form in the food chain. This work demonstrates that a simple treatment with water of "silver pearls", meant for decoration of pastry, results in the release of a subfraction of silver nanoparticles. The number-based size and shape distributions of the single, aggregated, and/or agglomerated particles released from the silver pearls were determined by combining conventional bright-field TEM imaging with semiautomatic particle detection and analysis. In addition, the crystal structure of the particles was studied by electron diffraction and chemical information was obtained by combining HAADF-STEM imaging with EDX spectroscopy and mapping. The TEM results were confirmed by SP-ICP-MS. The representative Ag test nanomaterial NM-300 K was used as a positive control to determine the uncertainty on the measurement of the size and shape of the particles.
authors.affiliation: †EM-Service, Interactions and Surveillance, CODA-CERVA, Groeselenberg 99, 1180 Uccle, Belgium.
authors.forename: E
authors.initials: E
authors.lastname: Verleysen
authors.affiliation: †EM-Service, Interactions and Surveillance, CODA-CERVA, Groeselenberg 99, 1180 Uccle, Belgium.
authors.forename: E
authors.initials: E
authors.lastname: Van Doren
authors.affiliation: ‡Trace Elements Service, Chemical Safety of the Food Chain, CODA-CERVA, Leuvensesteenweg 17, 3080 Tervuren, Belgium.
authors.forename: N
authors.initials: N
authors.lastname: Waegeneers
authors.affiliation: †EM-Service, Interactions and Surveillance, CODA-CERVA, Groeselenberg 99, 1180 Uccle, Belgium.
authors.forename: P-J
authors.initials: PJ
authors.lastname: De Temmerman
authors.affiliation: †EM-Service, Interactions and Surveillance, CODA-CERVA, Groeselenberg 99, 1180 Uccle, Belgium.
authors.forename: M
authors.initials: M
authors.lastname: Abi Daoud Francisco
authors.affiliation: †EM-Service, Interactions and Surveillance, CODA-CERVA, Groeselenberg 99, 1180 Uccle, Belgium.
authors.forename: J
authors.initials: J
authors.lastname: Mast
mesh_terms: D005503:Food Additives / Q000737:chemistry*; D013058:Mass Spectrometry / Q000379:methods*; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D046529:Microscopy, Electron, Transmission; D010316:Particle Size; D012834:Silver / Q000032:analysis* / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D005503:Food Additives; D012834:Silver
keywords: energy dispersive X-ray spectroscopy; food matrix; image analysis; inductively coupled plasma mass spectrometry; silver nanoparticles; transmission electron microscopy