Universidade de Aveiro;
MOTIVATION: Dietary exposure has been considered part of the exposome, therefore food safety is essential for individual and public health. Unquestionably, it is necessary to assure that preventive mechanisms are available to the scientific community and regulators, that rapidly respond to emergent needs of safety assurance of, for example, the use of nanotechnology in the food industry.
BACKGROUND: Nanotechnology has many applications in the food industry, including improvement of organoleptic properties, extended shelf-life, or nutritional value. Yet, there is growing concern about the potential adverse health effects resulting from the use of engineered nanomaterials (ENM) as food additives. Evidence of toxicity associated with ingested ENM continues to grow, but several critical knowledge gaps exist, preventing regulators and industry from assessing the potential healthrisks. These knowledge assessing the potential health risks. These knowledge gaps include: 1) uncertain human exposure data; 2)lack of understanding of physicochemical ENM transformations within complex food matrices andwithin the gastrointestinal tract and their effect on bioavailability and toxicity; and 3) lack of validated, standardized methodologies dedicated to riskassessment aft er exposure by oral pathway to these xenobiotics.
Another concern is overlooking of mixture phenomena, as other chemicals, namely metals, can be found in food resulting from natural or anthropogenic sources, or as impurities of the ENM themselves. Metals, such as arsenic, cadmium, lead,and mercury accumulate in the body, lead to harmful effects over time and constitute an important issue of concern. Thorough understanding of the risk of ingesting mixtures of chemicals is challenging but needed, as highlighted by EU, WHO, EFSA, OECD and JRC. Previous works have shown that co-exposure to ENM and metals can result in potentiation and synergistic effects, but also in attenuation of toxicity. Due to this particularity, general dose-addition models do not estimate the reals risks of ENM-metal co-exposure.
