Investigation of the Presence of Inorganic Micro- and Nanosized Contaminants in Bread and Biscuits by Environmental Scanning Electron Microscopy

Abstract

A European project called "Nanopathology" allowed to develop a new diagnostic tool through which the presence of inorganic particulate matter in pathological human tissues of the digestive tract could be shown. This unexpected evidence induced the authors to put forward the hypothesis that that sort of contamination was present in ingested food. In order to demonstrate this hypothesis, 86 samples of wheat bread and 49 of wheat biscuits from 14 different countries were analyzed by means of an Environmental Scanning Electron Microscopy to detect inorganic, micro-, and nano-scaled contaminants. The X-ray microprobe of an Energy Dispersion Spectroscope was employed to identify their chemical composition. The results indicate that 40% of the samples analyzed contained foreign bodies as ceramic and metallic debris of probable environmental or industrial origin. Because of the great variety of chemical composition of the particulate matter, those contaminants were listed according to the most expressed element. The majority of these debris are not biodegradable, some are chemically toxic, and none of them have any nutritive value. The work discusses the possible origin of such a pollution and the role that it can play on human life.

Nanoparticles in Foods, Determination of

“…However, there are other useful techniques such as hydrodynamic chromatography (HDC), liquid chromatography (LC), capillary electrophoresis (CE), field-flow fractionation (FFF), and ion mobility techniques that could be used to separate nanoparticles. (84,86) Other potentially suitable spectroscopic techniques for nanoparticle characterization include X-ray photoelectron, Fourier transform infrared spectroscopy (FT-IR), optical-UV spectroscopy, and fluorescence spectroscopy. (83) …”

“…Microscopic techniques (imaging techniques) are the most frequently used to identify the presence of nanoforms in food. (82 -84,86,90 -92) The low level at which nanomaterials should be identified and/or quantified in complex food matrices such as fish, (20,90,93) shellfish, (94,95) water, (82,87) coffee, (84,87) soup, (84) milk, (87) milk and chocolate powder, (96) fresh vegetables, (82) caramel, (83) jaggery, (83) cornflakes (83) bread and biscuits, (83,86) and pancakes (84) represent a major analytical challenge.…”

Detection, characterization and quantification of inorganic engineered nanomaterials: A review of techniques and methodological approaches for the analysis of complex samples

“…On the other hand, the spatial resolution drops to several tens of nm. A pioneer investigation of nanoparticles by ESEM in food samples was conducted by Gatti et al [80]. Luo et al [81] explored the application of ESEM to directly characterize the size distribution of a range of The use of electron microscopy for ENMs characterization in different types of samples has been considered in different reviews involving environmental [7,8,83], food [8,20], and biomaterials [71] analysis.…”

Scientific basis of nanotechnology, implications for the food sector and future trends

“…Indeed, a more comprehensive understanding of food structures from micro down to nano (i.e., macromolecular) scale has been attained by the complementary use of different types of microscopies. In addition to more conventional ones, i.e., LMs e bright field and polarized LM, fluorescence microscopy, CLSM (Dufour, 2011;El-Bakry & Sheehan, 2014;Sheen, Bao, & Cooke, 2008;van de Velde, van Riel, & Tromp, 2002), EFLM (Peighambardoust, Dadpour, & Dokouhaki, 2010) e and EMs e SEM and TEM (El-Bakry & Sheehan, 2014), cryo-SEM and cryo-TEM, STEM, ESEM and ASEM, EDX spectroscopy and microanalysis (Gatti, Tossini, Gambarelli, Montanari, & Capitani, 2009;B. James, 2009), also SPM techniques -AFM, SNOM, STM (Liu & Cheng, 2011;H.…”