Following a request from the European Commission to the European Food Safety Authority (EFSA), the Panel on Food Additives and Nutrient Sources added to Food (ANS) was asked to provide a scientific opinion on the assessment of orthosilicic acid-vanillin complex (OSA-VC) as a novel food ingredient in the context of Regulation (EC) No 258/97. Following the outcome of the novel food ingredient assessment, the Panel was also asked to evaluate the safety of OSA-VC when added for nutritional purposes to food supplements as a source of silicon, and on the bioavailability of silicon from this source in the context of Directive 2002/46/EC. The safety of silicon, in terms of the amounts that may be consumed, is outside the remit of the ANS Panel.
Data from literature have established that silicon is typically present in food in the form of OSA and as such is readily absorbed from the gastrointestinal tract in humans and then readily excreted in urine. Therefore, in order to address the Terms of Reference of the current mandate, and consistently with previous scientific opinions issued on other sources of silicon, the Panel considered that bioavailability of OSA from orthosilicic acid-vanillin complex as the basis for the evaluation of the bioavailability of silicon from that source.
The present assessment is based on the initial dossier submitted by the applicant and on additional data generated upon request from the Panel. The ANS Panel assessed the safety of orthosilicic acid-vanillin complex as a novel food ingredient in line with the principles laid down in Commission Recommendation 97/618/EC. Limited biological and toxicological data obtained with orthosilicic acid-vanillin complex were submitted by the applicant as part of the dossier. The applicant provided a justification for not complying with the Tier 1 requirements of the 2012 ANS Panel ‘Guidance for submission for food additive evaluations’ by demonstrating that under the conditions of simulated intestinal digestion (pH 6.8) and in the absence of digestive enzymes, the complex between OSA and vanillin is dissociated. The Panel was therefore of the opinion that no additional toxicological data were required and based its conclusions on the information available for its two components, OSA and vanillin.
The applicant has provided evidence that the two components of the complex are linked by electrostatic bonds and that the complex is stable only in an acidic environment. The Panel considered that the analytical data provided by the applicant do not fully support the identity of the material as a complex between OSA and vanillin.
With respect to the results from the stability tests of orthosilicic acid-vanillin complex the Panel noted that single measurements of pH, Si and vanillin made at the different time points did not show significant variations from the proposed specifications. The Panel considered that there would be no safety implications if the complex disassociated over time but that this could decrease the bioavailability of silicon from the proposed source orthosilicic acid-vanillin complex.
With respect to the bioavailability of silicon from orthosilicic acid-vanillin complex, the Panel acknowledged that this has been demonstrated only in a single randomised, placebo-controlled, crossover study conducted in 14 healthy subjects administered either 15 mL of orthosilicic acid-vanillin complex solution or placebo. Plasma silicon levels were used as a surrogate for absorption and measured at baseline and at different intervals within a period of 6 hours. Urinary silicon excretion was also measured as a secondary endpoint, at baseline and after 3 and 6 hours from ingestion of either the supplement or placebo.
The study demonstrated a significant increase in the plasma silicon concentration, with maximum concentrations achieved within 3 hours from intake of supplemental silicon. Urinary excretion in the 6-hour period accounted for 21.1% of the ingested silicon dose and also in this case, it was significantly different from the placebo group.
The Panel considered the study demonstrated that OSA, measured as silicon (form of silicon not determined), is bioavailable following ingestion of orthosilicic acid-vanillin complex and appears similar to values reported for other OSA sources measured as silicon in the literature.
The applicant proposed the use of OSA-orthosilicic acid-vanillin complex supplement solution in a standard dose of 15 mL/day of dietary supplement (containing 98.9% orthosilicic acid-vanillin complex complex), equivalent to 14.8 mL OSA-VC. The proposed use is limited to the adult population and not intended for children.
The daily consumption of orthosilicic acid-vanillin complex at the daily dose recommended by the applicant would provide a supplemental intake of silicon of approximately 10–18 mg/day which would result in an estimated total intake from supplement use and from the diet of roughly 30–70 mg silicon/day, thus not exceeding the safe upper level of supplemental silicon intake of 700 mg/day of Si for adults as set by the UK Expert group on Vitamins and Minerals (EVM) in 2003.
The maximum vanillin intake resulting from the consumption of orthosilicic acid-vanillin complex would be less than 0.3 mg/kg body weight (bw) per day, corresponding to less than 5% of the acceptable daily intake (ADI) value for vanillin of 10 mg/kg bw per day established by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) in 2002.
The Panel concluded that there would be no safety concern with the proposed use and use level of orthosilicic acid-vanillin complex as a novel food ingredient intended to be used as a source of silicon in food supplements for the adult population as proposed by the applicant.
The Panel concluded that OSA, measured as silicon, is bioavailable following ingestion of orthosilicic acid-vanillin complex and appears similar to values reported in the literature for other established sources of OSA (measured as silicon).
The Panel recommended that the specifications for the novel food ingredient to contain parameters for ethanol, phosphorus and phosphate ion which are residuals from the manufacturing process.
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