Aluminum bioaccessibility in infant formulas

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Aluminum bioaccessibility in infant formulas commercialized in Brazil

Esther Lima de PaivaUNICAMP/ ITAL

Raquel Fernanda MilaniITAL

Marcelo Antonio MorganoITAL

Juliana Azevedo Lima PalloneUNICAMP

Adriana Pavesi Arisseto-BragottoUNICAMP

10.37885/210203410

https://dx.doi.org/10.37885/210203410

591Avanços em Ciência e Tecnologia de Alimentos - Volume 3

Keywords: Infant Formula; Bioaccessibility; Aluminium; Food Analysis; in Vitro Digestion Method; Inorganic Contaminants.

ABSTRACT

The present study provides information about the bioaccessible fraction of aluminium (Al) in 16 samples of infant formulas using an optimized in vitro digestion method and inductively coupled plasma optical emission spectrometry (ICP OES). The bioaccessibility varied from 3.0% to 34% and the minimum and maximum values of Al in the bioaccessible fraction were 18.66–29.22 μg kg–1, 36.60-71.48 μg kg–1 and 19.60–160.2 μg kg–1 for starters, fol-low up and specialized infant formula samples, respectively. The bioaccessibility varied between the analyzed infant formulas depending on sample composition, ingredients, age consumption indications, food matrix (dietary fat and fiber), food processing, co-ingested food and nutrient availability status.


INTRODUCTION

Human milk is the optimal source of nutrition for infants (Boquien, 2018; Picciano, 2017) and, in general, poor breastfeeding practices have been associated with higher risks of infectious disease and morbidity in developing and developed countries (Heymann, Raub, & Earle, 2013; Stuebe, 2009). In the last decades, infants have been offered infant formula from the first month due to its convenience, ready availability and due to medical conditions that prevent the mother from nursing (Nabulsi et al., 2014). Infant formulas are liquids or re-constituted powders that infants consume as replacements for, or supplementary to, breast milk. They are typically produced from animal or plant sources and are mostly dairy-based or soy-based food products (Bermejo et al., 2000). Infant formula is the major source of nu-trients for many infants and a unique source of food during the first months of life (Bermejo et al., 2000; Rodriguez Rodriguez, Sanz Alaejos, & Diaz Romero, 2000).

However, the existence of pollutants and toxic metals, such as aluminium (Al), in infant formula may put children’s health at risk (aPaiva et al., 2019). Human exposure to toxic metals, especially infants, has increased significantly due to urbanization, industrialization and greater anthropogenic emissions. The combination of infants’ lower body weight, immature kidneys and liver, decreased capacity of detoxification and vulnerability of the myelin central nervous system make infants particularly susceptible to toxic substances (Dhamo & Shabani, 2014; Landrigan et al. 2003; Hulin et al., 2014). Moreover, human exposure to Al is identified as a possible contributor to neurodegenerative / neurodevelopmental diseases, such as multiple sclerosis and Alzheimer’s disease (Ahmed, et al., 2016; Mold, 2018).

Aluminum is the third most abundant element in the earth’s crust (8%) and the first amongst the metals. Due to its elevated reactivity, it is found combined with oxygen to form its main ore, bauxite (Al2O3), as well as in the form of silicates, oxides and hydroxides and it is also found as a component naturally present in potable water and in additives composed of Al salts combined with other elements such as sodium and fluorine, and complexed with organic material (Hardisson & Gonzalez, 2017; Cozzolino, 2005).

The European Food Safety Authority (EFSA) established a Tolerable Weekly Intake (TWI) for Al of 1 mg/kg body weight (bw) (EFSA, 2008), whilst in its 74th meeting, the Joint FAO/WHO Expert Committee on Food Additives (JECFA) confirmed the value of the PTWI (Provisional Tolerable Weekly Intake) for Al as being 2 mg/kg bw, which is applied to all the Al compounds in foods, including food additives (FAO/WHO, 2011; CAC, 2018). JECFA observed that the PTWI is likely to be exceeded in some population groups, particularly children, who regularly consume foods containing Al-based additives or ingredients. The Committee also inferred that exposure to this metal by infants fed infant formulae is high and recommended further investigations with these products. In a recent study, bPaiva et al.

593Avanços em Ciência e Tecnologia de Alimentos - Volume 3592Avanços em Ciência e Tecnologia de Alimentos - Volume 3

(2019) reported the total Al concentrations in infant formulas commercialized in Brazil, with important findings regarding Al exposure of newborns and infants.

Therefore, due to the relevant concern about Al toxicity, and considering the particular features of infants to Al exposure, better food control strategies are needed, especially tho-se destined for children. Additionally, the information about inorganic constituents usually indicates the total concentrations to be ingested and not the amount that will be effectively absorbed by the body. This type of information could be provided by studies of bioaccessibility (the amount of the element that is released into the gastrointestinal tract from its matrix) and bioavailability (the fraction of the element which is absorbed from the gastrointestinal tract by the human organism, reaches the bloodstream and is then used in biological functions) (Minekus et al., 2014; Machado et al., 2017; Peixoto et al., 2016).

The interest in bioaccessibility of chemical elements has been growing in recent years, and many of them have been assessed in different food matrices, such as baby food (Do Nascimento da Silva et al., 2013; Do Nascimento da Silva et al., 2018), cereal products (Fu and Cui, 2013; Khouzam et al., 2011; Laparra et al., 2007; do Nascimento da Silva et al., 2013; Peixoto et al., 2016; Bhatia et al., 2013; Dominguez- González et al., 2010; Vitali et al., 2008; Yang et al., 2014), biscuit (Vitali et al., 2008), lettuce (Do Nascimento da Silva et al., 2015), beef (Menezes et al., 2018), coffee (Alongi et al., 2019), berries (Pereira et al., 2018) and cheese (Ayala-Bribiesca et al., 2017; Khouzam et al., 2011), using different experimental models of in vitro digestion.

Some important issues have been addressed in the literature such as the influence of food structures and the synergism or antagonism between food components, as well as the standardization of methods to evaluate the soluble fractions of a food during the gastrointesti-nal digestion. However, bioaccessibility studies of Al are still limited with regard to food for in-fants and children (Souza et al., 2019; Pereira et al., 2018; Melø et al., 2008; Khalifa & Ahmad, 2010) and no information was found in the literature concerning data on Al bioaccessibility in infant formulas. Therefore, the aim of the present work was to evaluate the bioaccessible fraction of Al in this type of product using an optimized in vitro digestion method followed by optical emission spectrometry with an inductively coupled plasma source (ICP OES).

MATERIAL AND METHODS

Material, reagents and equipment

All of the reagents used in the research were of or above analytical grade. Water (18.2 MΩ.cm) was purified with reverse osmosis (Gehaka, São Paulo, Brazil) while nitric acid (HNO3) purification (Distillacid, Berghof, Eningen, Germany) was achieved with a sub-boiling


distiller. Hydrogen peroxide (H2O2) 30% (m/v) was provided by Merck (Darmstadt, Germany) in order to perform total Al mineralization. A certified 100 mg L–1 standard solution (Specsol, Quimlab, Jacareí, Brazil) in a 0.5% HCl solution (v/v) (Merck, Darmstadt, Germany) was used to prepare the analytical curves. Two certified reference materials were employed to evaluate the method accuracy: egg powder (EGGS-1, National Research Council, Canada) and a diet (Typical Diet, NIST SRM 1548a).

The following reagents were used for the bioaccessibility assay: sodium hydrogen carbo-nate (NaHCO3, >99.7 %), alpha-amylase (saliva solution) from Aspergillus oryzae (30 U mg–1), lactase (85,300 USP), pepsin porcine gastric mucosa (>250 U mg–1), bile from bovine and ovine (bile acid mixture) and pancreatin from porcine pancreas (8 x USP) (Sigma-Aldrich, Saint Louis USA). A dubnoff shaking water bath (NT 230, Nova Técnica, Piracicaba, Brazil) and a pHmeter (Starter 3100, Ohaus, Parsippany, EUA) were also used in the experiments.

Samples

A total of 16 samples of infant formulas was acquired in the city of Campinas, SP, Brazil from distinct batches and different brands (designated as A to D). The samples were stored in a dry place at room temperature (25 °C) and the main ingredients contained in the products are shown in Table 1. The digestion in vitro assay was performed in all referred samples, which were selected among the products considered in the present study to represent spe-cific matrix composition for infant formulas. All measurements of the bioaccessible fraction of Al were performed in triplicate and the results were expressed as percentages.


Table 1. Description of common ingredients of infant formulas according to the consumption indication and composition.

Sample composition Ingredients

Starter formulas

Lactose, Whey protein concentrate, Palm olein, Skimmed milk, Palm kernel oil, Canola oil, Corn oil, Calcium citrate, Potassium chloride, Potassium citrate, Magnesium chlo-ride, Sodium citrate, Ferrous sulfate, Zinc sulfate, Copper sulfate, Potassium iodide, Manganese sulfate, Sodium selenite, Vitamin C, Vitamin E, Niacin, Calcium pantothe-nate, Vitamin A, Vitamin B6, Vitamin B2, Vitamin D, Vitamin B1, Folic acid, Vitamin K, Biotin, Fish oil, Soy lecithin, Arachidonic acid, L-arginine, L-carnitine, Nucleotides, Taurine, Choline bitartrate, Inositol.

Follow up formulas

Skim powdered milk, Corn syrup solids, Lactose, Palm oil, Coconut oil, Soybean oil, Sunflower oil, Mixture of arachidonic acid from M. alpina oil and Docosahexaenoid acid from C. cohnii oil, Calcium carbonate, Sodium citrate, L-Ascorbic Acid, Maltodextrin, Choline chloride, Dibasic Magnesium Phosphate, Ferrous sulfate, Taurine, Potas-sium citrate, D-alpha-tocopheryl acetate, Cytidine 5-monophosphate, Zinc sulfate, Retinyl palmitate, L-Ascorbic Acid, Nicotinamide, Myo-inositol, Colecalciferol, Acid 5-monophosphate disodium salt, Fitomenadione, Adenosine 5-monophosphate, Guanosine disodium 5-monophosphate, D-calcium pantothenate, Cupric sulfate, Cyanocobalamin, Thiamine Chloride Hydrochloride, Pyridoxine hydrochloride, Ribo-flavin, Manganese sulfate, N-Pteroyl-L-glutamic acid, Sodium selenite, D-biotin, Soy lecithin, Ascorbyl palmitate

Specialized formulas

Without lactose

Maltodextrin, Palm olein, Whey protein concentrate, Canola oil, Coconut oil, Potas-sium caseinate, Calcium citrate, Potassium chloride, Sodium citrate, Dibasic Calcium Phosphate, Tribasic calcium phosphate, Magnesium chloride, Ferrous sulfate, Zinc sulfate, Copper sulfate, Potassium iodide, Manganese sulfate, Sunflower oil, Soy le-cithin, L-Ascorbic Acid, Nicotinamide, D-calcium pantothenate, DL-Alpha-tocopheryl acetate, Riboflavin, Thiamine mononitrate, Retinoyl acetate, Pyridoxine hydrochloride, N-Pteroyl-L-glutamic acid, Phylloquinone, B-biotin, Colecalciferol, Meso-inositol, Cya-nocobalamin, C. cohnii oil, M. alpina oil, Cytidine 5-monophthalate,Cytidine 5’-mo-nophosphate disodium salt , Adenosine 5-monophosphate, disodium salt of guanosine 5-monophosphate, Choline bitartrate, L-carnitine, Taurine, Potassium hydroxide.

Iron fortified

Skim powdered milk, Corn syrup solids, Lactose, Palm oil, Coconut oil, Soybean oil, Sunflower oil, M. alpina oil, Arachidonic acid, Docosahexaenoid acid from C. cohnii oil, Calcium carbonate, Sodium citrate, Sodium L-Ascorbic Acid, Maltodextrin, Choline chloride, Dibasic Magnesium Phosphate, Ferrous sulfate, Taurine, Potassium citrate, D-alpha-tocopheryl acetate, Cytidine 5-monophosphate, Zinc sulfate, Retinyl palmitate, L-Ascorbic Acid, Nicotinamide, Myo-inositol, Colecalciferol, Acid 5-monophosphate disodium salt, Phytonadione, Adenosine 5-monophosphate, Guanosine disodium 5-monophosphate, D-calcium pantothenate, Cupric sulfate, Cyanocobalamin, Thiami-ne chloride hydrochloride, Pyridoxine hydrochloride, Riboflavin, Manganese sulfate, N-Pteroyl-L-glutamic acid, Sodium selenite, D-biotin, Soy lecithin, Ascorbyl palmitate.

Soy-based

Maltodextrin, Palm oil, Canola oil, Coconut oil, Sunflower oil, Soybean protein, Tribasic Calcium Phosphate, Potassium chloride, Calcium carbonate, Tripotassium citrate, Trisodium citrate, Hydrogen magnesium phosphate, Choline chloride, Magnesium and citric acid salts, L-Ascorbic Acid, Taurine, L-ascorbate, Myo-inositol, Ferrous sul-fate, DL-alpha-tocopheryl acetate, Zinc sulfate, L-carnitine, Nicotinamide, D-calcium pantothenate, D-biotin, Cyanocobalamin, Riboflavin, Retinyl palmitate, N-Pteroyl-L--glutamic acid, DL-alpha-tocopherol, Thiamine chloride hydrochloride, Colecalciferol, Pyridoxine hydrochloride, Cupric sulfate, Potassium iodide, Phytonadione, Sodium selenite, Lecithin.

Determination of total Al

A sample of 1.0 g of reconstituted infant formula (3.0 g powder dissolved in 20 mL of water) was weighed into a digestion flask and 8 mL of purified HNO3 plus 2 mL H2O2 were added and maintained in contact overnight according to the described method optimized by bPaiva et al. (2019). The total Al concentration was determined in the reconstituted in-fant formula sample.


Determination of Al bioaccessibility

Dialysis method

The in vitro digestion model was performed according to Perales et al. (2006), consi-dering the gastrointestinal system of the infant with some adaptations. The quantities and concentrations of the enzymes solution were optimized taking into account the gastrointestinal capacity of the infant. Approximately 10 mL of reconstituted infant formula with water were transferred to clean erlenmeyer flasks and mixed with water to a final volume of 20 mL. The pH of the samples was adjusted to 7.0 and 4 mL of saliva solution were added for salivary digestion. The mixture was incubated at 37 °C in a shaking water bath for 5 min. Thereafter, the samples were acidified to pH 2.0 with 6 mol L−1 hydrochloric acid (HCl) with addition of 0.3 mL of a porcine pepsin preparation (1.6 g of porcine pepsin in 10 mL 0.1 mol L−1 HCl). The mixture was incubated at 37 °C in a shaking water bath for 2 h. To stop the gastric digestion phase, the samples were maintained for 10 min in an ice bath. The gastric digest solution added by pancreatin-bile was titrated with 0.5 mol L−1 NaHCO3 solution to determine the volume of base needed to increase the pH to about 7.5. Dialysis bags (Sigma-Aldrich, Saint Louis, EUA, with cut-off from 12.000 to 16.000 Da and porosity of 25 Å), containing 20 mL of freshly prepared 0.5 mol L−1 NaHCO3 solution and water, were immersed in the pepsin digests and incubated in a shaking water bath at 37 °C. After 30 min, 0.75 mL of pancreatin-bile salt mixture (0.4 g porcine pancreatin and 2.52 mg bile bovine per 100 mL of 0.1 mol L−1 NaHCO3) were added and incubated in a shaking water bath at 37 °C for more 2 h. The samples were maintained in the ice bath for 10 min to stop intestinal digestion. Dialysates were transferred for weight to graduate tubes and used to determine Al as previously described.

Determination of the optimum concentration of NaHCO3

The optimum dialysis concentration of NaHCO3 was calculated using titratable acidity (Shiowatana et al., 2006). Titratable acidity was defined as the number of equivalents of NaOH required to titrate the amount of digest to a pH of 7.5. It was determined using standard 1 mol L–1 NaHCO3 as titrant. This concentration of NaHCO3 changed the pH of the dialysate to 5.0–6.0 after 30 min of dialysis and gradually increased the pH to 7.0–7.5 on the addition of pancreatin-bile extract.


Method validation for Al quantification in infant formula

Accuracy, repeatability, linearity, detection limit (LOD) and quantification limit (LOQ) were evaluated according to the National Institute of Metrology, Standardization and Industrial Quality (INMETRO, 2017) and reported by bPaiva et al. (2019).

For the concentration range from 2 to 200 μg L–1 of Al, a satisfactory correlation coeffi-cient value was found (r²>0.999), showing the linearity of the analytical curve. The LOD and LOQ were determined using 10 replicates of an analytical blank, multiplied by the sample dilution factor (8.3 x). The values found for infant formulas were: LOD (3 s) = 16 μg kg–1 and LOQ (5 s) = 30 μg kg–1, with “s” being the standard deviation value of the 10 blank replicates.

In order to determine the repeatability of the method, the intra-day coefficients of varia-tion (CV) were evaluated in different samples of infant formula (n=8). The mean value found was 8% satisfying the conditions recommended by the Official Methods of Analysis (AOAC, 2013) with a maximum CV of 25% for the range concentration. The accuracy of the method was evaluated in two certified reference materials (CRM): Typical Diet (SRM 1548a - Typical Diet) and Egg Powder (NRC EGGS - Egg Power) with results varying from 87% to 97%, in accordance with the AOAC (2013) guidelines, which establish a range from 75 to 120%, for the studied concentration.

RESULTS

The results obtained for Al bioaccessibility (%) in infant formula samples from different commercial brands are displayed in Table 2, which also presents the Al total content and the concentration in the dialyzed fraction. Total Al concentrations in infant formula samples were previously discussed by bPaiva et al. (2019).

It was observed that the highest levels of Al in the bioaccessibe fraction were present in specialized formula brand B iron fortified (160.2 µg kg–1), followed by follow up brand B (95.96 µg kg–1) and brand A (83.56 µg kg–1), and soy-based brand A (55.49 µg kg–1). The lowest observed value was present in starter infant formula brand C (18.66 µg kg–1).

The findings show that the bioaccessibility for all analyzed samples varied from 3% to 34%, which may be related to the composition and characteristics of each sample. For starters formulas, the evaluated samples presented bioaccessibility ranging from 8.5% to 13%. For follow up samples, the range obtained varied from 4% to 20%, and among specialized infant formulas the found bioaccessibility values were 19% for the sample without lactose, 34% for the iron fortified, whilst for soy-based ones the observed range was between 3% and 11%.


Table 2. Total Al content, Al in the bioaccessible fraction and bioaccessibility (expressed as % of total concentration) in infant formulas.

Consumption indi-cation Brand Number of

samplesTotal Al(μg kg–1)

Bioaccessibility

Bioaccessible fraction (μg kg–1) %

Starter

A 1 296 ± 0.4 29.22 ± 3.1 10

B 1 231 ± 25 25.02 ± 1.7 8.5

C 1 206 ± 3.4 18.66 ± 3.1 9.0

D 1 195 ± 4.7 24.97 ± 0.3 13

Follow up

A 2353 ± 3.2 27.63 ± 1.6 8.0

410 ± 4.1 83.56 ± 2.0 20

B 2337 ± 76 47.01 ±3.9 14

492 ± 3.8 95.96 ± 1.2 20

C 1 179 ± 20 36.60 ± 2.8 20

D 2975 ± 102 43.52 ± 0.4 4.0

919 ± 73 54.81 ± 1.8 6.0

Specialized formulas

Iron fortifiedWithout lactose

B 1 468 ± 36 160.2 ± 9.4 34

C 1 253 ± 11 49.41 ± 8.8 19.0

Soy based

A 1 510 ± 28 55.49 ± 4.1 11

C 1 678 ± 155 19.60 ± 0.8 3.0

D 1 557 ± 21 41.27 ± 2.8 7.0

DISCUSSION

Table 2 shows the different samples analyzed, mean Al concentration in the bioacces-sible fraction, standard deviations, and bioaccessible percentage obtained for Al in standard infant formulae (cow milk-based), specialized and soy-based considering the indications for consumption.

The obtained mean values of Al in the bioaccessible fraction for starter, follow-up and specialized formulas were 24.46 μg kg–1, 53.38 μg kg–1 and 65.19 μg kg–1 respectively. Higher values were found for follow up and specialized formula compared to starter ones and this may be due to the greater variety of composition and additional ingredients. The higher mean contents found in some specialized formulae suggest that the need to greatly modify the raw material with aggressive treatments (such as protein hydrolysis) can result in a greater exposure of the product to a larger amount of Al during manufacture due to the


addition of chemicals and contact with machines and powder particles (Navarro-Blasco & Alvarez-Galindo, 2003).

In the current literature, few studies are related to the bioaccessibility of contaminants, especially Al in infant foods. In a recent study conducted by Souza et al. (2019), the Al bioac-cessible fraction of corn flour, rice and oat, and rice cereals was determined. Only a multi-cereal sample presented Al concentration of 1.04 mg kg–1 in the dialysable fraction, which corresponds to 6% of bioaccessibility and is similar to the obtained value for brand D follow up formula (6%) in the present study. aPaiva et al. (2020) also determined the Al bioaccessible fraction in infant cereals and found low values for multicereals varying from2.2% to 5%. Those values are comparable with the current percentages obtained for soy-based brand C (3%) and follow up brand D (4%) infant formulas.

Pereira et al. (2018) evaluated the bioaccessible fraction of some minerals inclu-ding Al present is some berries produced in São Paulo state, Brazil such as blackberry, raspberry, blueberry and strawberry, obtaining Al fractions in percentage of 3%, 2,4%, 33% and 4%, respectively (expressed as % of total concentration). bPaiva et al. (2020) found the bioaccessible fraction in infant foods varying from 0.5% to 48% according to the sample composition (salty purees, fruit purees, infant drinks and petit suisse).

Studies on the digestibility and absorption of phytonutrients such as vitamins, carote-noids, polyphenols, curcuminoids, polyunsaturated fatty acids, proteins, peptides, dietary fibers, oligosaccharides and minerals have shown, according to Thakur et al. (2020), that phytonutrient bioaccessibility has been further enhanced by the addition of oil, fat and cer-tain enzymes. Moreover, the group states that the bioaccessibility depends on food matrix (dietary fat and fiber), food processing, co-ingested food and nutrients status. Therefore, the distinct composition and required ingredients of infant formulas may explain the difference in Al bioaccessibility observed between the samples.

Theoretical calculations were used in a study by Do Nascimento da Silva et al. (2015) to determine the hydration energies of the polyphenols and the binding energies of the cel-lulose monomer and polyphenols to the metals in order to better understand the effects of certain matrix components on the bioaccessibility of chemical components. The obtained results were also consistent with the concept of hard and soft acids and bases (HSAB), whi-ch indicates that Al3+ and Fe3+ are hard acids. Therefore, Al3+ and Fe3+ are less polarizable compared to other metals, and polyphenols and cellulose contain OH– and RCOO– groups, which are hard bases. Thus, the interactions of fiber sources (cellulose) and polyphenols with Fe3+ and Al3+ tend to be more stable than the interactions of these compounds with Zn2+ and Cd2+, for example (Shriver, 1999). The strongest interaction of Al with cellulose may explain the fact that in spite of high total Al content, previously determined by bPaiva et al.


(2019), the samples presented low bioaccessibility, especially those containing soy, such as brand C (3.0%) and brand D (7.0%).

In addition to their binding energies, Do Nascimento da Silva et al. (2013) also calculated the hydration energies of the polyphenols to evaluate the solubility of these compounds. Thus, the correlation between the amount of polyphenols and the Al bioaccessibility from different baby foods could be determined. It was observed that lower polyphenol content means a greater interaction between the elements and less soluble structures, such as proteins, fibres and phytates, which leads to smaller bioaccessible fractions. The low bioaccessible fraction observed in Table 2 for starters infant formulas may be strongly related to the large amou-nt of proteins. In this regard, it is interesting to note that, in general, starter infant formulas present lower bioacessible fraction compared to the follow up ones due to the larger amount of proteins, once that the label declares the presence of whey protein concentrate in their composition. Nevertheless, the high bioaccessibility showed by iron fortified (specialized formula, 34%) might be explained due to presence of skimmed milk instead of whole milk or protein concentrate. Although the theoretical results show that the interaction between Al and polyphenols is the strongest, which would lead to greater bioaccessibility for this element, its interaction with cellulose is also the strongest. The interaction with cellulose may be the most important factor governing the bioaccessibility of elements in foods that contain larger amounts of cellulose than polyphenols. In addition, the cellulose structures are less soluble, which will more strongly affect the bioaccessibility of Al.

Further, some studies have associated low mineral absorption with the presence of antinutritional factors, such as phytates, which are present in plant seeds, grains and, at high amounts, in wheat bran, acting as the main stored form of phosphate in plant seeds (aPaiva et al., 2019; Do Nascimento et al., 2015). Regarding total Al content and its bioaccessible fraction, some parameters must be taken into account, such as the element forms (different chemical compounds), the behavior of organometallic species and complexes in the gastroin-testinal tract, and the interactions with the food matrix (Khouzam, Pohl, & Lobinski, 2011).

CONCLUSIONS

In the present study, it was possible to determine the Al bioaccessible fraction of infant formulas through an adapted in vitro approach considering the gastrointestinal system of children. The highest Al bioaccessible fraction content was observed in specialized infant formulas followed by follow up samples, with mean bioaccessibility values varying from 3% to 34% depending on the sample ingredients and composition. The findings highlight the importance of assessing Al exposure given that the inclusion of other foods in the diet can increase its overall intake, which may represent a health concern, especially for frequent


users. The data obtained in this study will contribute to the global assessment of potential health risks associated with Al exposure, suggesting the need to identify ways of monitoring the quality of ingredients used in infant food production and to establish research to explain the mechanism of toxicity associated with Al.

CONFLICT OF INTEREST

The authors declare no conflict of interest.

ACKNOWLEDGMENTS

The authors acknowledge the São Paulo Research Foundation (FAPESP) [Grant number 2017/11334-8]; the Brazilian National Council for Scientific and Technological Development (CNPq) [141085/2017-7] and the Brazilian Federal Agency for Support and Evaluation of Graduate Education (CAPES) [Finance code 001].

REFERÊNCIAS

1. Ahmed, A. H., Mohammed, E. P., Amin, M. M. & Abdel-Raheem, D. A. N. (2016). Aluminum Level in Infants’ Powdered Milk Based Formulae. Journal of Advanced Veterinary Research, 6(4), 104-107. Available at: https://advetresearch.com/index.php/AVR/article/view/14. Accessed 18.02.21.

2. Alongi, M., Calligaris, S., & Anese, M. (2019). Fat concentration and high- pressure homo-genization affect chlorogenic acid bioaccessibility and α- glucosidase inhibitory capacity of milk-based coffee beverages. Journal of Functional Foods, 58, 130-137. https://doi.or-g/10.1016/j.jff.2019.04.057

3. AOAC – Association of Official Agricultural Chemists. (2013). Appendix K: Guidelines for Dietary Supplements and Botanicals.

4. Ayala-Bribiesca, E., Turgeon, S. L., & Britten, M. (2017). Effect of calcium on fatty acid bio-accessibility during in vitro digestion of Cheddar-type cheeses prepared with different milk fat fractions. Journal of Dairy Science, 100, 2454-2470. https://doi.org/10.3168/jds.2016-11902

5. Bermejo, P., Peña, E., Domınguez, R., Bermejo, A., Fraga, J. M., & Cocho, J. A. (2000). Spe-ciation of iron in breast milk and infant formulas whey by size exclusion chromatography-high performance liquid chromatography and electrothermal atomic absorption spectrometry. Talanta, 50(6), 1211–1222. https://doi.org/https://doi.org/10.1016/S0039-9140(99)00233-7

6. Bhatia, P., Aureli, F., D’Amato, M., Prakash, R., Cameotra, S.S., Nagaraja, T.P. & Cubadda, F. (2013). Selenium bioaccessibility and speciation in biofortified Pleurotus mushrooms grown on selenium-rich agricultural residues. Food Chemistry, 140, 225–230. https://doi.org/10.1016/j.foodchem.2013.02.054


7. Bilal, M., Iqbal, H.M., Hu, H., Wang, W., & Zhang, X., 2017. Enhanced bio-catalytic performance and dye degradation potential of chitosan-encapsulated horseradish peroxidase in a packed bed reactor system. Science Total Environment. 575, 1352–1360. https://doi.org/10.1016/j. scitotenv.2016.09.215.

8. Boquien, C. Y. (2018). Human milk: An ideal food for nutrition of preterm newborn. Frontiers in Pediatrics, 6, 1–9. https://doi.org/10.3389/fped.2018.00295

9. Codex Alimentarius Commission (CAC) (2018). Working document for information and use in discussions related to contaminants and toxins in the GSCTFF. 12 th Session Utrecht, The Netherlands, 12 - 16 March 2018.

10. Cozzolino, S. M. F. (2005). Biodisponibilidade de nutrientes. Editora Manole.

11. Dhamo, K., & Shabani, L. (2014). Testing infant milk formulae for lead and cadmium. Interna-tional Refereed Journal of Engineering and Science, 3(3), 51-53. Available at: http://www.irjes.com/Papers/vol3issue3/G03035153.pdf. Accessed 11.02.21.

12. Dominguez-González, R., Romaris-Hortas, V., Garcia-Sartal, C., Moreda-Piñeiro, A., Barciela--Alonso, M.D.C., & Bermejo-Barrera, P. (2010). Evaluation of an in vitro method to estimate trace elements bioavailability in edible seaweeds. Talanta, 82, 1668–1673. https://doi.org/10.1016/j.talanta.2010.07.043

13. Do Nascimento da Silva, E., Leme, A. B., Cidade, M., & Cadore, S. (2013). Evaluation of the bioaccessible fractions of Fe, Zn, Cu and Mn in baby foods. Talanta, 117, 184–188. https://doi.org/10.1016/j.talanta.2013.09.008

14. Do Nascimento da Silva, E., Heerdt, G., Mirla Cidade, M., Catarinie Diniz Pereira, C. D., Mor-gon, N. H., & Cadore, S. (2015). Use of in vitro digestion method and theoretical calculations to evaluatethe bioaccessibility of Al, Cd, Fe and Zn in lettuce and cole by inductively coupled plasma mass spectrometry. Microchemical Journal, 119, 152–158. https://doi.org/10.1016/j.microc.2014.12.002

15. Do Nascimento da Silva, E., Farias, L.O., & Cadore, S. (2018). The total concentration and bioaccessible fraction of nutrients in purees, instant cereals and infant formulas by ICP OES: a study of Dietary Recommended Intakes and the importance of using a standardized in vitro digestion method. Journal of Food Composition and Analysis, 68, 65–72. https://doi.org/10.1016/j.jfca.2017.06.007

16. European Food Safety Authority (EFSA) (2008). Safety of aluminium from dietary intake. Scien-tific opinion of the Panel on Food Additives, Flavourings, Processing Aids and Food Contact Materials (AFC). EFSA Journal, 754:1–34.

17. Food and Agriculture Organization / World Health Organization (FAO/WHO) (2011). Seventy--fourth meeting of the Joint FAO/WHO Expert Committee on Food Additives. Rome: Summary report of the seventy-fourth meeting of JECFA. 2011.

18. Fu, J. & Cui, Y. (2013). In vitro digestion/Caco-2 cell model to estimate cadmium and lead bioaccessibility/bioavailability in two vegetables: the influence of cooking and additives. Food and Chemical Toxicology, 59, 215–221. https://doi.org/10.1016/j.fct.2013.06.014

19. Hardisson, A., Revert, C., & González-, D. (2017). Aluminium exposure through the diet. hSOA - Journal of Food Science and Nutrition, 3, 1-10. https://doi.org/10.24966/FSN-0176/100020


20. Heymann, J., Raub, A., & Earle, A. (2013). Breastfeeding policy: a globally comparative analysis. Bulletin of the World Health Organization, 91, 398–406. https://doi.org/10.2471/BLT.12.109363.

21. Hulin, M., Bemrah, N., Nougadère, A., Volatier, J. L., Sirot, V., & Leblanc, J. C. (2014). Assess-ment of infant exposure to food chemicals: the French Total Diet Study design. Food Additives & Contaminants: Part A, 1–14. https://doi.org/10.1080/19440049.2014.921937

22. Ikem, A., Nwankwoala, A., Odueyungbo, S., Nyavor, K., & Egiebor, N. (2002). Levels of 26 elements in infant formula from USA, UK, and Nigeria by microwave digestion and ICP–OES. Food Chemistry, 77, 439–447. https://doi.org/10.1016/S0308-8146(01)00378-8

23. Instituto Nacional de Metrologia, Qualidade e Tecnologia (INMETRO) (2017). Orientação sobre validação de métodos de ensaios químicos. Instituto Nacional de Metrologia, Normalização e Qualidade Industrial. Revisão 6, Julho.

24. Khalifa, A. S. & Ahmad, D. (2010). Determination of key elements by ICP-OES in commercially available infant formulae and baby foods in Saudi Arabia. African Journal of Food Science, 4(7), 464 – 468. Available at: http://www.academicjournals.org/ajfs. Accessed 08.02.21.

25. Khouzam, R. B., Pohl, P., & Lobinski, R. (2011). Bioaccessibility of essential elements from white cheese, bread, fruit and vegetables. Talanta, 86, 425–428. https://doi.org/10.1016/j.ta-lanta.2011.08.049

26. Koo, Y.-C., Chang, J.-S., & Chen, Y. C. (2018). Food claims and nutrition facts of commercial infant foods. Plos One, 13(2), e0191982. https://doi.org/10.1371/journal.pone.0191982

27. Landrigan, P. J., Kimmel, C. A., Correa, A., & Eskenazi, B. (2003). Children’s health and the environment: public health issues and challenges for risk assessment. Environmental Health Perspectives, 112, 257–265. https://doi.org/10.1289/ehp.6115

28. Laparra, J.M., Velez, D., Barbera, R., Montoro, R., & Farre, R. (2007). Bioaccessibility and transport by Caco-2 cells of organoarsenical species present in seafood. Journal of Agricultural and Food Chemistry, 55, 5892–5897. https://doi.org/10.1021/jf070490f

29. Luo, Y., Guo, W., Ngo, H.H., Nghiem, L.D., Hai, F.I., Zhang, J., ... & Wang, X.C. (2014). A review on the occurrence of micropollutants in the aquatic environment and their fate and removal during wastewater treatment. Science Total Environment. 473, 619–641. https://doi.org/10.1016/j.scitotenv.2013.12.065.

30. Machado, I., Cesio, M.V. & Pistón, M. (2017). In vitro bioaccessibility study of As, Cd, Cu, Fe, Ni, Pb and Zn from raw edible artichoke heads (Cynara cardunculus L. Subsp. Cardunculus). Microchemical Journal, 133, 663–668. https://doi.org/10.1016/j.microc.2017.03.005

31. Melø, R., Gellein, K., Evjea, L., & Syversen, T. (2008). Minerals and trace elements in com-mercial infant food. Food and Chemical Toxicology, 46, 3339–3342. https://doi.org/10.1016/j.fct.2008.08.007

32. Menezes, E. A., Oliveira, A. F., França, C. J., Souza, G. B., & Nogueira, A. R. (2018). Bioac-cessibility of Ca, Cu, Fe, Mg, Zn, and crude protein in beef, pork and chicken after thermal processing. Food Chemistry, 240, 75-83. https://doi.org/10.1016/j.foodchem.2017.07.090

33. Minekus, M., Alminger, M., Alvito, P., Ballance, S., Bohn, T., Bourlie, C., ... & Brodkorb, A. (2014). A standardised static in vitro digestion method suitable for food – an international con-sensus. Food Function, 5, 1113–1124. https://doi.org/10.1039/c3fo60702j


34. Mold, M., Umar, D., King, A., & Exley, C. (2018). Aluminium in brain tissue in autism. Journal of Trace Elements in Medicine and Biology, 46, 76–82. https://doi.org/10.1016/j.jtemb.2017.11.012

35. Nabulsi, M., Hamadeh, H., Tamim, H., Kabakian, T., Charafeddine, L., Yehya, N., ... & Sidani, S. (2014). A complex breastfeeding promotion and support intervention in a developing cou-ntry: study protocol for a randomized clinical trial. BMC Public Health, 14(1), 36. https://doi.org/10.1186/1471-2458-14-36

36. Navarro-Blasco & Alvarez-Galindo, J. I. (2003). Aluminium content of Spanish infant formula. Food Additives & Contaminants, 20(5), 470-48. https://doi.org/10.1080/0265203031000098704.

37. aPaiva, E. L., Medeiros, C., Milani, R. F., Morgano M. A., Pallone, J. A. L., & Arisseto-Bragot-to, A. P. (2020). Aluminum content and effect of in vitro digestion on bioaccessible fraction in cereal-based baby foods. Food Research International, 131, 108965. https://doi.org/10.1016/j.foodres.2019.108965

38. bPaiva, E. L., Medeiros, C., Andrekowisk, M. I. F., Milani, R. F., Morgano M. A., Pallone, J. A. L., & Arisseto-Bragotto A. P. (2020). Aluminium in infant foods: Total content, effect of in vitro digestion on bioaccessible fraction and preliminary exposure assessment. Journal of Food and Composition Analysis, 90, 103493. https://doi.org/10.1016/j.jfca.2020.103493

39. aPaiva, E. L., Morgano, M. A., & Arisseto-Bragotto, A. P. (2019). Occurrence and determination of inorganic contaminants in baby food and infant formula. Current Opinion in Food Science, 30, 60-66. https://doi.org/10.1016/j.cofs.2019.05.006

40. bPaiva, E. L., Milani, R. F., Morgano, M. A., & Arisseto-Bragotto, A. P. (2019). Aluminum in infant formulas commercialized in Brazil: Occurrence and exposure assessment. Journal of Food Composition and Analysis, 82, 103-230. https://doi.org/10.1016/j.jfca.2019.06.002

41. Peixoto, R. A., Devesa, V., Velez, D., Cervera, M. L., & Cadore, S. (2016). Study of the factors influencing the bioaccessibility of 10 elements from chocolate drink powder. Journal of Food Composition and Analysis, 48, 41-47. https://doi.org/10.1016/j.jfca.2016.02.002

42. Pereira, C. C., da Silva, E. N., Souza, A. O., Vieira, M. A., Ribeiro, A. S., & Cadore, S. (2018). Evaluation of the bioaccessibility of minerals from blackberries, raspberries, blueberries and strawberries. Journal of Food Composition and Analysis, 68, 73–78. https://doi.org/10.1016/j.jfca.2016.12.001

43. Perales, S., Barberá, R., Largada, M. J., & Farré, R. (2006). Bioavailability of zinc from infant foods by in vitro methods (solubility, dialyzability and uptake and transport by Caco-2 cells). Journal of the Science of Food and Agriculture, 86, 971–978. https://doi.org/10.1002/jsfa.2445

44. Picciano, M. F. (2017). Nutrient Composition of Human Milk. Pediatric Clinics, 48(1), 53–67. https://doi.org/10.1016/S0031-3955(05)70285-6

45. Rasheed, T., Li, C., Bilal, M., Yu, C., & Iqbal, H.M. (2018). Potentially toxic elements and envi-ronmentally-related pollutants recognition using colorimetric and ratiometric fluorescent probes. Science Total Environment. 640, 174–193. https://doi.org 10.1016/j.scitotenv.2018.05.232

46. Rodriguez Rodriguez, E. M., Sanz Alaejos, M., & Diaz Romero, C. (2000). Concentrations of iron, copper and zinc in human milk and powdered infant formula. International Journal of Food Sciences and Nutrition, 51(5), 373–380. https://doi.org/10.1080/096374800426966

https://doi.org/10.1016/j.scitotenv.2018.05.232


47. Saracoglu, S., Saygi, K. O., Uluozlu, O. D., Tuzen, M., & Soylak, M. (2007). Determination of trace element contents of baby foods from Turkey. Food Chemistry, 105, 280–285. https://doi.org/10.1016/j.foodchem.2006.11.022

48. Shiowatana, J., & Sopon, P., & Upsorn, S., Sutthinun, T., & Atitaya, S. (2006). Enhancement Effect Study of Some Organic Acids on the Calcium Availability of Vegetables: Application of the Dynamic in Vitro Simulated Gastrointestinal Digestion Method with Continuous-Flow Dialysis. Journal of agricultural and food chemistry. https://doi.org/10.1021/jf062073t.

49. Shriver, D. F., Atkins, P. W., & Langford, C. H. (1999). Inorganic Chemistry, 3rd ed. OxfordU-niversity Press, Oxford.

50. Souza, A.O., Pereira, C.C., Heling, A.I., Oreste, E.Q., Cadore, S., Ribeiro, A.S., & Vieira, M.A. (2019). Determination of total concentration and bioaccessible fraction of metals in infant cereals by MIP OES. Journal of Food Composition and Analysis, 77, 60-65. https://doi.org/10.1016/j.jfca.2019.01.006.

51. Stuebe A. (2009) The risks of not breastfeeding for mothers and infants. Reviews in Obstetri-cs and Gynecology, 2(4), 222-231. Available at: https://pubmed.ncbi.nlm.nih.gov/20111658/. Accessed 22.02.21

52. Thakur, N., Raigond, P., Singh, Y., Mishra, T., Singh, B., Lal, M. K., & Dutt, S. (2020). Recent updates on bioaccessibility of phytonutrients. Trends in Food Science & Technology, 97, 366-380. https://doi:10.1016/j.tifs.2020.01.019

53. Thomaidis, N.S., Asimakopoulos, A.G., & Bletsou, A.A. (2012). Emerging contaminants: a tutorial mini-review. Global NEST J. 14 (1), 72–79.

54. Vitali, D., Dragojevic, I.V., & Sebecic, B. (2008). Bioaccessibility of Ca, Mg, Mn and Cu from whole grain tea-biscuits: impact of proteins, phytic acid and polyphenols. Food Chemistry, 110, 62–68. https://doi.org/10.1016/j.foodchem.2008.01.056

55. World Health Organization (WHO) (2009). Infant and Young Child Feeding. Model Chapter for Text books for Medical Students and Allied Health Professionals, Geneva, Switzerland. Avai-lable athttp://whqlibdoc.who.int/publications/2009/9789241597494_eng.pdf: http://whqlibdoc.who.int/publications/2009/9789241597494_eng.pdf. Accessed 18.02.21.

56. Yang, C., Paik, S., Ryu, J., Choi, K., Kang, T.S., Lee, J.K., Song, C.W., & Ko, S. (2014). Dyna-mic light scattering-based method to determine primary particle size of iron oxide nanoparticles in simulated gastrointestinal fluid. Food Chemistry, 161, 185–191. https://doi.org/10.1016/j.foodchem.2014.04.022

https://pubmed.ncbi.nlm.nih.gov/20111658/

http://whqlibdoc.who.int/publications/2009/9789241597494_eng.pdf

http://whqlibdoc.who.int/publications/2009/9789241597494_eng.pdf

https://doi.org/10.1016/j.foodchem.2014.04.022

https://doi.org/10.1016/j.foodchem.2014.04.022

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Aluminum bioaccessibility in infant formulas