Aluminium content of foods originating from aluminium-containing food additives

Assessment of Exposure to Aluminum through Consumption of Noodle Products

This study aimed to determine aluminum (Al) contents in commonly consumed noodles and estimate the risk of Al exposure through the consumption of noodles in the Thai population. A total of 80 samples, 20 samples each of rice stick noodles, egg noodles, wide rice noodles, and Thai rice noodles was purchased from markets in Bangkok Metropolitan and other four provinces in each region of Thailand. Wet digestion and graphite furnace atomic absorption spectrometry (GFAAS) were used to determine Al contents. Exposure assessment of Al was conducted by applying the consumption amounts of noodles from the national consumption survey and the Al contents of the noodle samples. The hazard quotient (HQ) was calculated to estimate the risk of exposure to Al. Aluminum contents in the noodles ranged from not detected to 630 mg/kg. Exposure to Al from consumption of each noodle product in all age groups was lower than the provisional tolerable weekly intake (PTWI). However, Al exposures in children calculated from the high consumer models and Al exposures in all age groups from the worst-case scenarios were higher than the PTWI, indicating potential adverse health effects. Consumers who regularly consume large amounts of noodle products containing Al may be at risk of having adverse health effects.

Parkin-mediated mitophagy protects against aluminum trichloride-induced hippocampal apoptosis in mice via the mtROS-NLRP3 pathway

Aluminum is a neurotoxic food contaminant. Aluminum trichloride (AlCl3) causes hippocampal mitochondrial damage, leading to hippocampal injury. Damaged mitochondria can release mitochondrial reactive oxygen species (mtROS) and activate nucleotide-binding oligomerization domain-like receptor-containing 3 (NLRP3) inflammasomes and apoptosis. E3 ubiquitin ligase PARK2 (Parkin)-mediated mitophagy can attenuate mitochondrial damage. However, the role of mitophagy in AlCl3-induced mice hippocampal damage and its regulatory mechanism remain elusive. First, C57BL/6 N mice were treated with 0, 44.825, 89.65, and 179.3 mg/kg body weight AlCl3 drinking water for 90 d. Apoptosis, NLRP3-inflammasome activation and mitochondrial damage were increased in AlCl3-induced hippocampal damage. In addition, Parkin-mediated mitophagy peaked in the middle-dose group and was slightly attenuated in the high-dose group. Subsequently, we used wild-type and Parkin knockout (Parkin-/-) mice to investigate the AlCl3-induced hippocampal damage. The results showed that Parkin-/- inhibited mitophagy, and aggravated AlCl3-induced mitochondrial damage, NLRP3-inflammasome activation, apoptosis and hippocampal damage. Finally, we administered MitoQ (mtROS inhibitor) and MCC950 (NLRP3 inhibitor) to AlCl3-treated Parkin-/- mice to investigate the mechanism of Parkin-mediated mitophagy. The results showed that inhibition of mtROS and NLRP3 attenuated hippocampal NLRP3-inflammasome activation, apoptosis, and damage in AlCl3-treated Parkin-/- mice. These findings indicate that Parkin-mediated mitophagy protects against AlCl3-induced hippocampal apoptosis in mice via the mtROS-NLRP3 pathway.

Fluorescent dyes based on rhodamine derivatives for bioimaging and therapeutics: recent progress, challenges, and prospects

Since their inception, rhodamine dyes have been extensively applied in biotechnology as fluorescent markers or for the detection of biomolecules owing to their good optical physical properties. Accordingly, they have emerged as a powerful tool for the visualization of living systems. In addition to fluorescence bioimaging, the molecular design of rhodamine derivatives with disease therapeutic functions (e.g., cancer and bacterial infection) has recently attracted increased research attention, which is significantly important for the construction of molecular libraries for diagnostic and therapeutic integration. However, reviews focusing on integrated design strategies for rhodamine dye-based diagnosis and treatment and their wide application in disease treatment are extremely rare. In this review, first, a brief history of the development of rhodamine fluorescent dyes, the transformation of rhodamine fluorescent dyes from bioimaging to disease therapy, and the concept of optics-based diagnosis and treatment integration and its significance to human development are presented. Next, a systematic review of several excellent rhodamine-based derivatives for bioimaging, as well as for disease diagnosis and treatment, is presented. Finally, the challenges in practical integration of rhodamine-based diagnostic and treatment dyes and the future outlook of clinical translation are also discussed.

A portable front face fluorescent system for in situ detection of aluminum in flour foods

A simple and rapid method for in situ detection of aluminum in flour food was developed by using a self-made portable front face fluorescent system (PFFFS). The effects of pH, temperature, reaction time, protective agent and masking agent on the detection of Al³⁺ were investigated. The use of fluorescent probe protective agent, interfering ion masking agent, multi-point collection measurements and the working curves based on the analyte content in the real samples makes the present method have high accuracy, selectivity and reliability for in situ detection of Al³⁺ in flour foods. By comparison with the ICP-MS the accuracy and reliability of the present method were verified. The results showed that when 97 real samples were analyzed the Al³⁺ content values obtained by the present method and those obtained by ICP-MS method reached a highly significant correlation, with r ranging from 0.9747 to 0.9844. The self-made PFFFS combined with fluorescent probe does not require sample digestion, and can quickly detect Al³⁺ in flour food within 10 min. Therefore, the present method based on using FFFS has good practical application value for in-situ rapid detection of Al³⁺ in flour foods.

Large scale occurrence of aluminium-rich shallow groundwater in the Pearl River Delta after the rapid urbanization: Co-effects of anthropogenic and geogenic factors

Aluminium(Al)-rich (> 0.2 mg/L) groundwater has received more concerns because of its harmful to human beings. Origins of large-scale occurrence on Al-rich groundwater in urbanized areas such as the Pearl River Delta (PRD) are still little known. The current work was conducted to investigate spatial distribution of Al-rich groundwater in the PRD, and to discuss its origins in various aquifers. For that, 265 groundwater samples and 15 river water samples were collected, and 21 hydrochemical parameters including Al were analyzed by using conventional analytical procedures. The results showed that groundwater Al concentrations were up to 22.64 mg/L, and Al-rich groundwater occurred in 15% of the area occupied by the PRD. Al-rich groundwater in the coastal-alluvial aquifer was about 2 times those in alluvial-proluvial and fissured aquifers, whereas the karst aquifer was absent. In the coastal-alluvial aquifer, Al-rich groundwater in the peri-urban area was 2 or more times those in urbanized and agricultural areas, whereas the remaining area was absent. By contrast, in the alluvial-proluvial aquifer, Al-rich groundwater in the remaining area was 1.5-3.5 times that in other areas; in the fissured aquifer, the distribution of Al-rich groundwater was independent of land-use types. The infiltration of wastewater from township enterprises was main anthropogenic source for Al-rich groundwater in urbanized and peri-urban areas, whereas irrigation of Al-rich river water was the main one in the agricultural area. Naturally dissolution of Al-rich minerals in soils/rocks, triggered by both of pH decrease resulted from nitrification of contaminated ammonium (e.g., sewage leakage, the use of nitrogen fertilizer) and acid deposition, was the main geogenic source for Al-rich groundwater in the PRD. The contribution of anthropogenic sources to Al-rich groundwater in the coastal-alluvial aquifer was more than that in alluvial-proluvial and fissured aquifers, whereas the contribution of geogenic sources was opposite. In conclusion, the discharge of township enterprises wastewater and ammonium-rich sewage, the emission of nitrogen-containing gas, and the use of nitrogen fertilizer should be preferentially limited to decrease the occurrence of Al-rich groundwater in urbanized areas such as the PRD.

Monitoring of Aluminum content in food and assessment of dietary exposure of residents in North China

Although the Chinese diet has become very abundant in the past 30 years, few people know that traditional Chinese diet is exposed to aluminium (Al). A total of 1232 samples were purchased during 2017-2019 and analysed for Al content with an inductively coupled plasma-mass spectrometry (ICP-MS) method. High Al levels were found in deep-fried dough sticks (mean 219 mg/kg), starch products (mean 84.5 mg/kg), and steam bread (mean 28.6 mg/kg). The average dietary Al exposure of residents in North China was 1.82 mg/kg bw/week, lower than the PTWI (provisional tolerable weekly intake). Deep-fried dough sticks (DFDS) are the main Al contributor in North China, providing 28.2% of the daily intake. The P95 dietary exposure to Al from DFDS was 2.3 mg/kg bw/week, exceeding the PTWI. Therefore, more attention should be paid to the health risk of exposure to Al from DFDS and starch products. Over-use of Al associated with food additives should be effectively controlled.

Human exposure assessment to potentially toxic elements (PTEs) from tofu consumption

Potentially toxic elements (PTEs) (V, B, Ba, Li, Sr, Cr, Ni, Al, Pb, Cd) were determined in 130 samples of different tofu types (natural, flavored, smoked, and fresh made) by ICP-OES (inductively coupled plasma optical emission spectrometry). Al was the most notable element found with the highest concentration (6.71 mg/kg ww) found in flavored tofu. Ni level (0.38 mg/kg) stands out in smoked tofu. European tofu has higher PTE levels than Chinese tofu. Organic-produced tofu has higher PTE concentrations than conventional produced tofu. A total of 200 g/day of smoked tofu confers a contribution percentage of 39.6% of its TDI (tolerable daily intake). In addition, 200 g/day of flavored tofu would mean a high Pb contribution with a 23.2% of the BMDL (benchmark dose level) set in 0.63 μg/kg bw/day to the development of nephrotoxicity. Mean consumption would not pose a risk to adults' health. Considering the obtained results, it would be advisable to establish limits for certain metals such as Pb, Al, and Ni in this type of product. Furthermore, it is recommendable to set consumer guidelines to some tofu types in order to avoid excessive intake of PTEs.

A novel fluorescent probe of aluminium ions based on rhodamine derivatives and its application in biological imaging

A new type of probe can be used for the detection of Al³⁺ in biological cells.

Development and Validation of Surveys to Estimate Food Additive Intake

(1) Background: The Food Agricultural Organization/World Health Organization (FAO/WHO) International Food Standards Codex Alimentarius CXS 192e International Food Standards (hereafter, CODEX) declares additives non-toxic, but they have been associated with changes to the microbiota changes and thinning of the mucus layer of the gut. Their widespread use has occurred in parallel with increased inflammatory bowel disease (IBD) incidence. This paper reports on the development and validation of surveys to estimate additive intake. (2) Methods: Dietitians created a food-additive database, with a focus on additives that have been associated with IBD. For each additive, information on the CODEX food-category they are permitted in and the associated maximum permissible levels (mg/kg) was recorded. Based on the database, questions to assess early life (part 1) and recent (part 2) additive intake were written. Forward–backward translation from English to Chinese was undertaken. Thirty-one individuals were evaluated to assess understandability. A further fifty-seven individuals completed the tool on two occasions, a fortnight apart; agreement was assessed using Cohen’s kappa coefficient or the intra-class correlation coefficient (ICC). (3) Results: The participants reported that it was difficult to remember food intake and estimate portion sizes. The participants also noted confusion around the term ‘home-grown’. Instructions and definitions were added; after this, respondents judged the questionnaires as clear. The average kappa coefficient for part 1 and part 2 questions were 0.61 and 0.67, respectively. The average ICC ranged from 0.30 to 0.94; three food lists were removed due to low reliability. (4) Conclusions: Two tools have been created and validated, in two languages, that reliably assess remote and recent food additive intake.

Aluminum and tin: Food contamination and dietary intake in an Italian population

Aluminum and tin are ubiquitous in the environment. In normal biological systems, however, they are present only in trace amounts and have no recognized biological functions in humans. High exposure to these metals can result in adverse health effects such as neurodegenerative diseases. In non-occupationally exposed subjects, diet is the primary source of exposure. In this study, we aimed at estimating dietary aluminum and tin intake in an Italian adult population. We measured aluminum and tin concentrations through inductively-coupled plasma mass spectrometry in 908 food samples. We also estimated dietary intake of these two metals, by using a validated semi-quantitative food-frequency questionnaire administered to 719 subjects (319 men and 400 women) recruited from the general population of the Emilia Romagna region, Northern Italy. We found the highest aluminum levels in legumes, sweets, and cereals, while the highest tin levels were in sweets, meat and seafood. The estimated median daily dietary intake of aluminum was 4.1 mg/day (Interquartile range - IQR: 3.3-5.2), with a major contribution from beverages (28.6%), cereals (16.9%), and leafy vegetables (15.2%). As for tin, we estimated a median intake of 66.8 μg/day (IQR: 46.7-93.7), with a major contribution from vegetables (mainly tomatoes) (24.9%), fruit (15.5%), aged cheese (12.2%), and processed meat (10.4%). This study provides an updated estimate of the dietary intake of aluminum and tin in a Northern-Italy adult population, based on data from a validated food-frequency questionnaire. The intake determined for this population does not exceed the established thresholds of tolerable intake.

[Survey of Aluminium Content of Processed Food Using Baking Powder (2015-2016)]

The aluminium (Al) content of Japanese confectionery and foods containing flour was investigated. Some of these items were investigated in previous studies, which examined foods that made use of baking powder containing aluminium potassium sulfate (Alum). Al was detected in 41 of the 123 samples at levels ranging from 0.01 (limit of quantitation) to 0.40 mg/g. The detection rate of Al in almost all confectionery (except Japanese confectionery) was decreased as compared with previous studies. However, the detection rate of Al in Japanese confectionery and foods containing flour was high. For 4 of the 41 samples tested, consuming one serving once a week would result in an Al intake exceeding the PTWI for young children (body weight=16 kg).

Effect of aluminum chloride on blood glucose level and lipid profile in normal, diabetic and treated diabetic rats

OBJECTIVES

The objectives of the study were to assess evaluate the effects of aluminum chloride (AlCl₃) on blood glucose and lipid levels in normal, diabetic, and glibenclamide-treated diabetic rats.

MATERIALS AND METHODS

Forty-two male Wistar rats were divided into seven groups of six each. Group I was normal control, Groups II and III were given AlCl₃50 and 100 mg/kg, and Group IV to VII were administered with streptozotocin (STZ) (60 mg/kg) intraperitoneally. Group IV was diabetic control, Group V in addition was given AlCl₃50 mg/kg, Group VI glibenclamide (10 mg/kg), and Group VII glibenclamide and AlCl₃(50 mg/kg) per-oral daily for 28 days. Blood glucose and lipid levels were estimated at base line, after diabetes was set in and on the last day of study. Histopathological changes in pancreas, liver, and kidney were studied.

RESULTS

No significant change was observed in blood glucose and lipid levels in Group I. Group II and III showed a dose-dependent significant increase in blood glucose was observed. Group V had a reduction in blood glucose but not to the nondiabetic level. Group VI had significant reduction in blood sugar. In Group VII, treated with glibenclamide and AlCl₃, there was no significant change in blood glucose reduction compared to Group VI. Lipid levels were reduced in groups treated with AlCl₃ and glibenclamide and not in other groups. Gross tissue damage was seen in pancreas in STZ group and in liver and kidney in AlCl₃ groups.

CONCLUSION

AlCl₃ administration in Wistar rats caused in significant hyperglycemia in normal rats, hypoglycemia in diabetic rats, and did not influenced hypoglycemic effect of glibenclamide and in addition, resulted in reduction in lipid levels.