Measurement of Nanomaterials in Foods: Integrative Consideration of Challenges and Future Prospects

Abstract

The risks and benefits of nanomaterials in foods and food contact materials receive conflicting international attention across expert stakeholder groups as well as in news media coverage and published research. Current nanomaterial characterization is complicated by the lack of accepted approaches to measure exposure-relevant occurrences of suspected nanomaterials in food and by broad definitions related to food processing and additive materials. Therefore, to improve understanding of risk and benefit, analytical methods are needed to identify what materials, new or traditional, are "nanorelevant" with respect to biological interaction and/or uptake during alimentary tract transit. Challenges to method development in this arena include heterogeneity in nanomaterial composition and morphology, food matrix complexity, alimentary tract diversity, and analytical method limitations. Clear problem formulation is required to overcome these and other challenges and to improve understanding of biological fate in facilitating the assessment of nanomaterial safety or benefit, including sampling strategies relevant to food production/consumption and alimentary tract transit. In this Perspective, we discuss critical knowledge gaps that must be addressed so that measurement methods can better inform risk management and public policy.

Is nano safe in foods? Establishing the factors impacting the gastrointestinal fate and toxicity of organic and inorganic food-grade nanoparticles

“…Consequently, suitable analytical tools are required to characterize nanoparticle properties, which have been reviewed elsewhere. 7,[101][102][103] In this section, we focus on the ways that nanoparticles may vary.…”

“…[3][4][5] Engineered nanoscale materials (ENMs) may be intentionally added to foods (such as nanoparticle-based delivery systems), or they may inadvertently find their way into foods (such as nanoparticles in packaging materials that leach into the food matrix). [6][7][8] ENMs are typically nanoparticles whose composition, size, shape, and interfacial properties are specifically designed to achieve one or more functional attributes. In particular, ENMs may be used to create delivery systems for nutrients, nutraceuticals, colors, flavors, and preservatives, or they may be used to modify the texture, appearance, or stability of foods.…”

Utility of models of the gastrointestinal tract for assessment of the digestion and absorption of engineered nanomaterials released from food matrices

“…These future research areas are being studied by the ILSI NanoRelease Food Additive project (Szakal et al, 2014a). Such studies will require more work to ensure the reliability of a variety of techniques including analytical digestion and detection.…”

“…A specific size range was not defined to allow the identification of methods relevant to a broad range of sizes. Elsewhere, the NanoRelease Food Additive project reviewed the influence of the physico-chemical properties of these materials on their stability in human gastrointestinal fluids and their permeability through mucus and epithelial cells (Szakal et al, 2014a). That work sets the stage for this review from the NanoRelease Food Additive project to identify models of the mammalian GI tract that can be used for the assessment of the fate of food-relevant NMs.…”

Interactions between engineered nanomaterials and agricultural crops: implications for food safety

“…Other promising advances include single particle inductively coupled plasma-mass spectrometry (spICP-MS), solid sampling highresolution-continuum source atomic absorption spectrometry (HR-CS AAS) and two-photon excitation microscopy (TPEM) (Wild and Jones, 2009;Feichtmeier and Leopold, 2013;Gray et al, 2013). However, the most advanced instrumentation platforms used for these types of studies are costly and of limited accessibility (Szakal et al, 2014). As such, a multidisciplinary and orthogonal approach is needed, including the development of new or hybridized measurement techniques, in order to promote the understanding of ENMs-crop interactions (GardeaTorresdey et al, 2014;Petersen et al, 2014).…”