Nickel intolerance disease: surface modification of a zeolite for direct human assumption and cultivation eco-sustainable strategy

The presence of nickel in environments dedicated to the cultivation of nickel-fixing fruit and vegetables determines non-negligible concentrations of this element in food. Furthermore, its widespread use in the metal and electronics industry makes human exposure to nickel practically inevitable. The toxicity of this metal is widely demonstrated, and in thousands of clinical cases and targeted tests, it has been possible to find a sensitivity to nickel by more than 5% of the population. This project proposes two solutions to the problem in which the use of zeolites is foreseen. The first consists of the intake of alimentary zeolite as a detoxifier from heavy metals, and the second is based on a nickel-free diet, possible thanks to the products of aeroponic agriculture. The properties of molecular sieve, together with those of a size and a chemical-physical composition compatible with the gastrointestinal tract, are present in a particular form of zeolite called clinoptilolite. The use of this substance, suitably modified to increase its ion-selectivity, as a food supplement prevents, through adsorption and ion exchange, the accumulation of toxins, free radicals, and heavy metals, including nickel. A definitive solution to the problem of nickel sensitivity lies in the upstream elimination of this metal from the fruit and vegetable production process thanks to the use of aeroponic cultivation systems. This system consists of the growth of plants in ideally isolated environments in which the water used can be treated with zeolite to remove nickel. These conditions allow for more controlled, efficient, and nutritionally safe growth of foods with a saving of water (90-95% less), nutrients and soil (80-90% less) compared to classic agriculture. In both cases, the adsorption efficiency of the zeolites strictly depends on the degree of crystallinity. According to the most recent studies, high purity clinoptilolite is synthesized through the sol-gel method, with structure directing agent (SDA), combined with the hydrothermal method where silica dioxide is the source of silicon and aluminium hydroxide is that of aluminium. The possibility of synthesizing clinoptilolite with a high degree of crystallinity and with specific adsorption functions within the gastrointestinal environment and in aeroponic cultivation plants would make an effective contribution to the goals of 2030 Agenda in terms of nutrition improvement, water saving, sustainable models of production and mitigation of climate change.