Aluminum forms in drinking water and risk of Alzheimer's disease

Fluorimetric methods for determination of aluminum in water resources utilizing newly synthesized N,N'-bis(2,5-dihydroxybenzylidene)-4,4'-diamino diphenyl ether

Industrial waste contaimnation of water sources is a serious environmental problem. As a result, it's critical to identify metallic contamination in water with precision, sensitivity, and accuracy. In acetonitrile, the fluorimetric parameters of N,N-'bis(2,5-dihydroxybenzylidene)-4,4'-diamino diphenyl ether (DHDPE) and aluminum complex were determined. In the acetonitrile medium, the best fluorescence intensity of the DHDPE-Al complex was observed at λex = 280 nm, λem = 391 nm (excitation and emission wavelengths). For optimum complex formation, the ideal pH, duration, and temperature were 4.5, 20 min, and 25 °C, respectively. Within the ranges of 0.027-0.27 and 0.27-2.70 ppm aluminum concentrations, [Al3+]-F.I. Calibration graphs were linear. The fluorimetric aluminum measurement method was applied to diverse water sources using the newly synthesized macro molecular Schiff base DHDPE as the ligand. The aluminum concentration in water inflow to KOSKI (Konya Water and Sewerage Administration) was doubled as a result of the examination when compared to other samples of water.

Dynamic Rare-Earth Metal-Organic Frameworks Based on Molecular Rotor Linkers with Efficient Emissions and Ultrasensitive Optical Sensing Performance

4,4',4″-Triphenylamine tricarboxylate (TPA-COOH) with a distinct molecular rotor structure was reacted with rare-earth (RE) metal ions to obtain seven dynamic RE-based luminescent MOFs (RE-LMOFs) (i.e., emission colors in the blue, yellow-green, red, and near-infrared regions and emission peak wavelengths between 400 and 1600 nm) via the effective transfer of absorbed energy from TPA-COOH to the RE metal ions through the antenna effect. Due to the large energy level difference between RE ions, it was rare in the early days to use the same ligand to construct energy-level matching RE-LMOF homologues with multiple RE metal centers. The uncoordinated oxygen atoms on the molecular rotor linkers in RE-LMOFs provide active sites that can specifically capture highly toxic metal ions and strong oxidative pollutants. The limit of detection (LOD) of RE-LMOF for Al(III) ions is far below the maximum concentration of Al(III) ions in drinking water stipulated by the U.S. Environmental Protection Agency (USEPA) and that for H2O2 is much lower than the H2O2 content in cancer cells, showing excellent application potential for diagnosing early cell cancelation.

Epigenetic Mechanisms of Aluminum-Induced Neurotoxicity and Alzheimer's Disease: A Focus on Non-Coding RNAs

Aluminum (Al) is known to induce neurotoxic effects, potentially contributing to Alzheimer's disease (AD) pathogenesis. Recent studies suggest that epigenetic modification may contribute to Al neurotoxicity, although the mechanisms are still debatable. Therefore, the objective of the present study was to summarize existing data on the involvement of epigenetic mechanisms in Al-induced neurotoxicity, especially AD-type pathology. Existing data demonstrate that Al exposure induces disruption in DNA methylation, histone modifications, and non-coding RNA expression in brains. Alterations in DNA methylation following Al exposure were shown to be mediated by changes in expression and activity of DNA methyltransferases (DNMTs) and ten-eleven translocation proteins (TETs). Al exposure was shown to reduce histone acetylation by up-regulating expression of histone deacetylases (HDACs) and impair histone methylation, ultimately contributing to down-regulation of brain-derived neurotrophic factor (BDNF) expression and activation of nuclear factor κB (NF-κB) signaling. Neurotoxic effects of Al exposure were also associated with aberrant expression of non-coding RNAs, especially microRNAs (miR). Al-induced patterns of miR expression were involved in development of AD-type pathology by increasing amyloid β (Aβ) production through up-regulation of Aβ precursor protein (APP) and β secretase (BACE1) expression (down-regulation of miR-29a/b, miR-101, miR-124, and Let-7c expression), increasing in neuroinflammation through NF-κB signaling (up-regulation of miR-9, miR-125b, miR-128, and 146a), as well as modulating other signaling pathways. Furthermore, reduced global DNA methylation, altered histone modification, and aberrant miRNA expression were associated with cognitive decline in Al-exposed subjects. However, further studies are required to evaluate the contribution of epigenetic mechanisms to Al-induced neurotoxicity and/or AD development.

Harnessing Moringa oleifera root powder (MORP) for the sustainable remediation of heavy metal contaminated water

Heavy metal environmental pollution is rapidly increasing due to the increase in industrialization and urbanization. Industrial processes, such as paint production, mining, and raw materials producing industries release effluents rich in heavy metals, like Pb2+, Cd2+, Cu2+, and Cr3+. These heavy metals are dangerous because they persist in nature, are non-biodegradable and they have high tendency to accumulate in the environment and in living organisms who are exposed to them. This work studied the removal of heavy metals (Cu, Pb, Cr, and Cd) from aqueous solution using Moringa oleifera root powder (MORP) as the adsorbent. The MORP was characterized by SEM, FTIR, BET, and XRD. Batch adsorption experiments carried out investigated the effects of adsorbate concentration, adsorbent dosage, agitation time, pH and temperature on adsorption. The optimum parameters are: contact time (90 min); pH (9); adsorbent dose (0.6); metal ion concentration (30 mg L-1) for Cr and 40 mg L-1 for the rest; and temperature (50 °C) for Cu and Pb, and 70 °C for Cr and Cd. These experimental data were analyzed with 5 isotherm models (Temkin, Flory-Huggins, Langmuir, D-R and Freundlich). The result obtained fitted best to Temkin isotherm in comparison to others. Kinetic studies revealed that the pseudo-second order kinetic model best described the adsorption (with high R2 values ranging from 0.9810-0.9976) compared to pseudo-first order and intra-particle diffusion kinetics model. Results of the thermodynamic study showed that the sorption process was endothermic for Cu and Pb, but exothermic for Cd and Cr. The adsorbent showed good adsorptive tendencies toward the ions studied, and could be applied on an industrial scale for the remediation of metal contaminated water.

Association between the Composition of Drinking Water and Cognitive Function in the Elderly: A Systematic Review

The prevalence of dementia increases with nearly 10 million new cases each year, with Alzheimer's disease contributing to 60-70% of cases. Environmental factors such as drinking water have been evaluated to determine if a relationship exists between trace elements in drinking water and the risk of developing cognitive disorders in the elderly. The purpose of the current systematic review was to evaluate an association between the composition of drinking water and cognitive function in the elderly. In accordance with the Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines, a literature search was conducted using PubMed and CINAHL databases. A total of 10 studies were included in the current systematic review. Aluminum is the most commonly evaluated trace element in studies (n = 8), followed by silica (n = 5), calcium (n = 4), and fluoride (n = 4). Aluminum exposure showed an increased risk of cognitive decline in four studies, with no association reported in the other studies. Higher silica and pH levels were shown to be protective against a decline in cognitive function. A similar protective effect of calcium was found in two studies. Future research should measure multiple trace mineral levels in all water sources to evaluate the impact on cognitive function.

Interaction of chitosan with nanoplastic in water: The effect of environmental conditions, particle properties, and potential for in situ remediation

Micro- and nanoplastic (MNP) pollution in aquatic ecosystems requires investigation on its source, transport, and extent to assess and mitigate its risks. Chitosan is a potential biomolecule for water treatment, but its interaction with MNP is undefined. In this work, chitosan-nanoplastic interaction was explored in the laboratory under environmentally relevant conditions using polystyrene (PS) nanoplastic (NP) as model particle to identify conditions at which PS-chitosan interaction resulted in aggregation. Aggregation limits NP transport and allows separation of NP for targeted remediation. The effect of environmental conditions (pH, salinity, dissolved organic matter (DOM) content), chitosan particle size and NP surface modification on chitosan-NP interaction was studied at various chitosan doses. PS aggregated at chitosan doses as low as 0.2 % w/w, while higher doses of chitosan resulted in re-stabilization of NP in solution, restoring the particle size to its initial value. Increasing pH, DOM, or carboxyl modification of the NP surface also improved NP stability in solution. Increased salinity of the solution caused aggregation of unmodified PS independent of chitosan, but carboxyl-modified PS remained stable and aggregated at the same chitosan doses across all salinity levels. Chitosan with low molecular weight promoted PS aggregation at lower doses. Notably, zeta potential (ZP) alone did not indicate chitosan-induced PS aggregation, which occurred independently of changes in ZP. DLVO calculations based on ZP, however, still indicated attractive interaction due to charge differences, albeit with less contrast at high pH, salinity, and DOM content. Additional insights gained in the work recommend caution when using spectrophotometric methods to assess NP removal. Overall, this study demonstrates that chitosan impacts NP transport and holds potential for water remediation of NP.

Coagulative removal of microplastics from aqueous matrices: Recent progresses and future perspectives

Coagulation-flocculation-sedimentation (CFS) system has been identified as one of the favored treatment technique in water/wastewater treatment systems and hence, it is crucial to comprehend the efficacy of different coagulants used in removing microplastics (MPs) from aqueous matrices. Henceforth, this study critically reviews the recent progress and efficacy of different coagulants used to date for MPs removal. This includes laboratory and field-scale studies on inorganic and organic coagulants, as well as laboratory-scale studies on natural coagulants. Inorganic and organic coagulants have varying MPs removal efficiencies such as: Fe/Al-salts (30 %-95 %), alum (99 %), and poly aluminum chloride (13 %-97 %), magnesium hydroxide (84 %), polyamine (99 %), organosilanes (>95 %), and polyacrylamide (85 %-98 %). Moreover, studies have highlighted the use of natural coagulants, such as chitosan, protein amyloid fibrils, and starch has shown promising results in MPs removal with sevral advantages over traditional coagulants. These natural coagulants have demonstrated high MPs removal efficiencies with chitosan-tannic acid (95 %), protein amyloid fibrils (98 %), and starch (>90 %). Moreover, the MPs removal efficiencies of natural coagulants are compared and their predominant removal mechanisms are determined. Plant-based natural coagulants can potentially remove MPs through mechanisms such as polymer bridging and charge neutralization. Further, a systematic analysis on the effect of operational parameters highlights that the pH affects particle surface charge and coagulation efficiency, while mixing speed affects particle aggregation and sedimentation. Also, the optimal mixing speed for effective MPs removal depends on coagulant type and concentration, water composition, and MPs characteristics. Moreover, this work highlights the advantages and limitations of using different coagulants for MPs removal and discusses the challenges and future prospects in scaling up these laboratory studies for real-time applications.

Global Scientific Research Landscape on Aluminum Toxicology

This study aimed to identify the landscape of current aluminum toxicity based on knowledge mapping of the 100 most-cited articles on toxicological aspects of aluminum in biological organisms. The research was searched in the Web of Science Core Collection (WoS-CC) with publications between 1945 and 2022. Data regarding authorship, title, journal, year of publication, citation count, country, keywords, study design, and research hotspots were extracted and all elected articles were analyzed. Our results showed that among the articles selected, literature review and in vivo studies were the most common study designs. The USA and England were found as the countries with most publications. Alzheimer's disease (AD), aluminum, and neurotoxicity were found as the most frequent keywords. The articles most cited in world literature suggested that aluminum exposure is associated with Alzheimer's disease, Parkinson's disease (PD), dialysis encephalopathy, amyotrophic lateral sclerosis, neurodegeneration changes, cognitive impairment, such as bone damage, oxidative alterations, and cytotoxicity.

Evaluation of Heavy Metal Pollution in the Blood Serum of Industrial Workers, Mosul, Iraq

The study was conducted in the two main industrial areas in Mosul, northern Iraq, where the study included measuring the number of heavy metals (cadmium, aluminum, mercury, chromium) in the blood of workers in those areas. For 20 workers, in contrast, blood samples were drawn from Mosul University employees. They were considered as a control group for being far from industrial activity and for 20 employees. An atomic absorption device was used to analyze blood samples after diluting. In addition, workers were divided into groups according to (age, smoking status, and period of occupational exposure). The results revealed statistically significant differences when comparing the samples of workers to the control group, while the results did not show significant differences between groups of workers. Keywords. Pollution, Blood Serum, Industrial Area.

A dose response effect of oral aluminum nanoparticle on novel object recognition memory, hippocampal caspase-3 and MAPKs signaling in mice

The increasing use of aluminum nanoparticles (nano-Al) leads to increased human exposure and might affect human health. Considering the suggested connection between aluminum exposure and Alzheimer's disease (AD) pathogenesis, there is a concern about the effect of nano-Al on cognitive function and brain health. This study was aimed to assess the effect of a 5-day oral gavage of aluminum oxide nanoparticle (nano-Al) on memory and the phosphorylation levels of hippocampal p38, JNK (c-Jun N-terminal kinase), ERK (extracellular signal-regulated kinase) as well as cleaved caspase-3 in mice. Adult male NMRI mice were treated with nano-Al in doses 5 and 10 mg/kg/oral gavage for 5 days. The test session of novel object recognition (NOR) task was performed on day 5. Following the NOR test, the hippocampi were isolated for western blot analysis to determine the total and phosphorylated levels of p38, JNK, ERK as well as cleaved caspase-3 proteins. The results showed that nano-Al oral gavage in doses of 5 and 10 mg/kg impairs NOR memory in mice. Moreover, the memory impairing effect of nano-Al coincided with a dose dependent increase in phosphorylated p38 and cleaved caspase-3 in the hippocampus. It also increased the ratio of phosphorylated to total content of ERK in the hippocampus while JNK signaling was not affected by nano-Al. This study showed that nano-Al in doses as low as 5 and 10 mg/ kg ingested for 5 days impairs NOR memory and activates p38, ERK and cleaved caspase-3 in the hippocampus.

Naproxen as a potential candidate for promoting rivastigmine anti-Alzheimer activity against aluminum chloride-prompted Alzheimer's-like disease in rats; neurogenesis and apoptosis modulation as a possible underlying mechanism

BACKGROUND AND AIM

Alzheimer's disease (AD) is one of the leading causes of dependence and disability among the elderly worldwide. The traditional anti-Alzheimer medication, rivastigmine, one of the cholinesterase inhibitors (ChEIs), fails to achieve a definitive cure. We tested the hypothesis that naproxen administration to the rivastigmine-treated aluminum chloride (AlCl3) Alzheimer's rat model could provide an additive neuroprotective effect compared to rivastigmine alone.

MATERIALS AND METHODS

The studied groups were control (Cont), AlCl3 treated (Al), rivastigmine treated (RIVA), naproxen treated (Napro), and combined rivastigmine and naproxen treated (RIVA + Napro). Rats' memory, spatial learning, and cognitive behavior were assessed followed by evaluation of hippocampal acetylcholinesterase (AChE) activity. Hippocampal and cerebellar histopathology were thoroughly examined. Activated caspase-3 and the neuroepithelial stem cells marker; nestin expressions were immunohistochemically assayed.

RESULTS

AD rats displayed significantly impaired memory and cognitive function, augmented hippocampal AChE activity; massive neurodegeneration associated with enhanced astrogliosis, apoptosis, and impaired neurogenesis. Except for the enhancement of neurogenesis and suppression of apoptosis, the combination therapy had no additional neuroprotective benefit over rivastigmine-only therapy.

CONCLUSION

Naproxen's efficacy was established by its ability to function at the cellular level, improved neurogenesis, and decreased, apoptosis without having an additional mitigating impact on cognitive impairment in rivastigmine-treated AD rats.

Environmental factors and risks of cognitive impairment and dementia: A systematic review and meta-analysis

BACKGROUND

Dementia is a challenging neurodegenerative disease. This systematic review aimed to summarize natural, physical, and social environmental factors that are associated with age-related cognitive impairment and dementia.

METHODS

We systematically searched PubMed, EMBASE, Web of Science, and PsychINFO till January 11, 2021 for observational studies. The hazard ratio (HR), relative risk (RR), and odds ratio (OR) with 95% confidence interval (CI) were aggregated using random-effects methods. The quality of evidence for each association was evaluated.

RESULTS

Of the 48,399 publications identified, there were 185 suitable for review across 44 environmental factors. Meta-analyses were performed for 22 factors. With high-to-moderate quality of evidence, risks were suggested in exposure to PM_2.5 (HR=1.24, 95%CI: 1.17-1.31), NO₂ (HR=1.07, 95%CI: 1.02-1.12), aluminum (OR=1.35, 95%CI: 1.14-1.59), solvents (OR=1.14, 95%CI: 1.07-1.22), road proximity (OR=1.08, 95%CI: 1.04-1.12) and other air pollutions, yet more frequent social contact (HR=0.82, 95%CI: 0.76-0.90) and more greenness (OR=0.97, 95%CI: 0.95-0.995) were protective. With low-to-very low quality, electromagnetic fields, pesticides, SO₂, neighborhood socioeconomic status, and rural living were suggested risks, but more community cultural engagement might be protective. No significant associations were observed in exposure to PM₁₀, NO_x, noise, silicon, community group, and temperature. For the remaining 22 factors, only a descriptive analysis was undertaken as too few studies or lack of information.

CONCLUSIONS

This review highlights that air pollutions, especially PM_2.5 and NO₂ play important role in the risk for age-related cognitive impairment and dementia.

Association between water and sanitation, air and emission pollution and climate change and neurological disease distribution: A study based on GBD data

Along with the urbanization and industrialization of countries, the prevalence of chronic diseases has increased. There is ample evidence that ambient pollution can play a major role in these diseases. This study aimed to investigate the association between neurological disorders (NDs) and their subtypes with environmental factors. In this country-level study, we used the age-standardized prevalence and incidence rate (per 100,000 populations) of NDs and its subtypes that have been taken from the Global Burden of Disease (GBD) database in 2019. We used correlation and regression analysis to assess the association between variables. Also, multivariable regression analysis was performed to identify the most important variables in NDs distribution. Age-adjusted NDs incidence rate was significantly higher in developed countries compared to developing countries (11345.25 (95% CI: 11634.88-11055.62) and 9956.37 (95% CI: 10138.66-9774.08)). Association results indicated that the impact of water and sanitation could be more effective than air pollution on NDs. The increase in water and sanitation index levels was positively correlated with NDs incidence rate and prevalence (regression coefficient (b) = 38.011 (SE = 6.50) and b = 118.84 (SE = 20.64), p < 0.001, respectively) after adjusting socio-economic and demographic factors. Furthermore, the incidence of NDs was negatively correlated with the increase in air quality (b = -16.30 (SE = 7.25), p = 0.008). Water and sanitation and their related factors are plausible factors in the distribution of NDs, which may be linked to the potential role of air and water pollution, such as heavy metals and particle matters. These results can be used by politicians and municipal service planners for future planning.

Modified Low-Temperature Extraction Method for Isolation of Bletilla striata Polysaccharide as Antioxidant for the Prevention of Alzheimer's Disease

Amyloid-β (Aβ) peptides play a key role in Alzheimer's disease (AD), the most common type of dementia. In this study, a polysaccharide from Bletilla striata (BSP), with strong antioxidant and anti-inflammatory properties, was extracted using a low-temperature method and tested for its efficacy against AD, in vitro using N2a and BV-2 cells, and in vivo using an AD rat model. The characterization of the extracted BSP for its molecular structure and functional groups demonstrated the effectiveness of the modified method for retaining its bioactivity. In vitro, BSP reduced by 20% reactive oxygen species (ROS) levels in N2a cells (p = 0.0082) and the expression levels of inflammation-related genes by 3-fold TNF-α (p = 0.0048), 4-fold IL-6 (p = 0.0019), and 2.5-fold IL-10 (p = 0.0212) in BV-2 cells treated with Aβ fibrils. In vivo, BSP recovered learning memory, ameliorated morphological damage in the hippocampus and cortex, and reduced the expression of the β-secretase protein in AlCl3-induced AD rats. Collectively, these findings demonstrated the efficacy of BSP for preventing and alleviating the effects of AD.

A bio-compatible pyridine-pyrazole hydrazide based compartmental receptor for Al3+ sensing and its application in cell imaging

For practical applications, the development of bio-compatible organic molecules as p-block ion chemosensors is critical. Herein, we report the single crystal (SC) of new pyridine-pyrazole derived Al³⁺ sensor H2PPC [(Z)-N'-(2,3-dihydroxybenzylidene)-5-methyl-1-(pyridin-2-yl)-1H-pyrazole-3-carbohydrazide] as well as its Cu-complex SC. The probe exhibits an "off-on" fluorescence response towards Al³⁺ ions, and this has been modulated with different solvents. For selective detection of Al³⁺ ions, a special coordination pocket in the structural backbone is advantageous. The chemosensor exhibits a submicromolar detection level (LOD = 4.78 μM) for Al³⁺. The density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations of H2PPC and [Al(HPP)2]+ (1) reveal that a change of the structural conformation of probe H2PPC upon complexation causes the pyrazole and pyridine units to create a specific cavity to tether Al³⁺, and consequently H2PPC proves to be a promising molecule for Al³⁺ detection. Furthermore, the probe has been successfully used to evaluate Al³⁺ as a low-cost kit using filter paper strips, and the in situ Al³⁺ ion imaging in Vero cells as well as A549 cell lines shows the sensor's nuclear envelope penetrability, indicating that it has great potential for biological and environmental applications.

Relationship between the expression of TNFR1-RIP1/RIP3 in peripheral blood and cognitive function in occupational Al-exposed workers: A mediation effect study

Aluminium (Al), not essential for biological activities, accumulates in the tissues. It exerts toxic effects on the nervous system, inducing in humans' irreversible cognitive impairment. In this study, a cluster sampling method was used to observe the cognitive function of long-term occupational Al-exposed workers in a large Al factory, and determine the expression of peripheral blood tumour necrosis factor receptor 1 (TNFR1), receptor-interacting protein 1 (RIP1), and RIP3. TNF-alpha, expressed in blood macrophages and microglia, with its receptors TNFR1, TR1 and TR3, enhances the necroptosis of neurons. Additionally, the relationship between the expression of TNFR1, RIP1, and RIP3 in the peripheral blood of long-term occupational Al-exposed workers and changes in their cognitive function was explored. The differences in the distributions of clock drawing test (CDT) scores among the three groups were statistically significant (P < 0.05). The results of correlation analysis showed that RIP1 and RIP3 protein contents were negatively correlated with mini-mental state examination (MMSE) and CDT scores (P < 0.05). Plasma Al content was positively correlated with other biological indicators (P < 0.05), and negatively correlated with MMSE and CDT scores (P < 0.05). Results showed that RIP3 protein had an incomplete mediation effect between plasma Al content and cognitive function. This suggests that Al may affect cognitive function by influencing the expression of TNFR1, RIP1, and RIP3 in the nervous system.

Investigate workers' health in the western industrial region, Mosul, Iraq

The current study aims to determine the level of heavy metal contamination in the Western Industrial Region of Mosul City, northern Iraq. Heavy metals such as( Pb ،Co ،Hg ) are measured In the blood serum of 40 workers in the main industrial areas of Mosul City. It was compared with the control group of (40) people from Mosul university, Where is Far away from the industrial areas and all activities. The results indicated a highly significant increase of P<0.001 in the serum of the workers in the industrial areas compared with the control group. The study investigates the impact of heavy metals on the workers' health in the industrial areas who are in direct contact with them.

Sustainable Removal of Microplastics and Natural Organic Matter from Water by Coagulation-Flocculation with Protein Amyloid Fibrils

Water contamination is a global threat due to its damaging effects on the environment and human health. Water pollution by microplastics (MPs), dissolved natural organic matter (NOM), and other turbid particles is ubiquitous in water treatment. Here, we introduce lysozyme amyloid fibrils as a novel natural bio-flocculant and explore their ability to flocculate and precipitate the abovementioned undesired colloidal objects. Thanks to their positively charged surface in a very broad range of pH, lysozyme amyloid fibrils show an excellent turbidity removal efficiency of 98.2 and 97.9% for dispersed polystyrene MPs and humic acid (HA), respectively. Additionally, total organic carbon measurements confirm these results by exhibiting removal efficiencies of 93.4 and 61.9% for purifying water from dispersed MPs and dissolved HA, respectively. The comparison among amyloid fibrils, commercial flocculants (FeCl₃ and polyaluminumchloride), and native lysozyme monomers points to the superiority of amyloid fibrils at the same dosage and sedimentation time. Furthermore, the turbidity of pristine and MP-spiked wastewater and lake water decreased after the treatment by amyloid fibrils, validating their coagulation-flocculation performance under natural conditions. All these results demonstrate lysozyme amyloid fibrils as an appropriate natural bio-flocculant for removing dispersed MPs, NOM, and turbid particles from water.

Interactions between magnetic particles and polyaluminum chloride on the coagulation behavior in humic acid-kaolin synthetic water treatment

Understanding the interactions between magnetic particles (MPs) and polyaluminum chloride (PACl) is essential to elucidate the magnetic seeding coagulation (MSC) process. However, little is known about how MPs interact with the different Al species coexisting in the PACl. Here, the relationships among pollutants removal, residual Al distribution, and floc properties were comparatively studied in the MSC and traditional coagulation (TC) processes to address this issue. The response surface analysis indicated that the interaction between PACl and MPs dosages exhibited significant effects on turbidity and DOC removal. Negligible changes of dissolved Al after MPs addition indicated the weak connection between Al_a and MPs. The formation of MPs-Al_b-HA complexes resulted in the increase of turbidity removal from 90.2% to 96.0% and the reduction of colloidal Al from 0.67 to 0.30 mg L^-1. Humic-like components could be adsorbed on MPs forming MPs-HA complexes, which enhanced the DOC removal from 55% to 58.5%. MPs addition produced loose flocs with a small floc fractal dimension value (1.74), so the average size and strength of flocs in the MSC process (425 μm and 49.7%) were lower than that in the TC process (464 μm and 58.3%). The cumulative volume percentage of large flocs (>700 μm) was decreased from 29.7% to 20.7% with MPs addition, indicating the disruption of large flocs and the reproduction of more fragments. The effective separation of these fragments by magnetic attraction maintained the efficient coagulation performance. This study provides new insights into the interaction mechanism of MPs and PACl in the MSC process.

Evaluation of Cerebellar Function and Integrity of Adult Rats After Long-Term Exposure to Aluminum at Equivalent Urban Region Consumption Concentrations

High amounts of aluminum (Al) are found in soil and water. It is highly bioavailable, which makes it an important agent of environmental imbalance. Moreover, Al is considered a neurotoxic agent that is associated with several neurodegenerative diseases. Thus, this study investigated the effects of long-term Al chloride (AlCl₃) exposure on motor behavior, oxidative biochemistry, and cerebellar tissue parameters. For this, adult Wistar rats were divided into three groups: Al-D1 (8.3 mg kg^-1 day^-1), Al-D2 (5.2 mg kg^-1 day^-1), and control (distilled water); all groups were orally exposed for 60 days by intragastric gavage. After the exposure period, animals performed the open field, elevated plus maze, rotarod, and beam walking tests. Then, the blood and cerebellum were collected to evaluate Al levels and biochemical and morphological analyses, respectively. Our results demonstrate that animals exposed to Al doses presented a higher Al level in the blood. In the spontaneous locomotor activity, Al exposure groups had traveled a lower total distance when compared with the control group. There was no statistically significant difference (p > 0.05) between exposed and control groups when anxiogenic profile, forced locomotion, fine motor coordination/balance, pro-oxidative parameter, and density Purkinje cells were compared. Thus, aluminum exposure in equivalent doses to human consumption in urban regions did not promote significant changes in the cerebellum or motor parameters.

Magnetic seeding coagulation: Effect of Al species and magnetic particles on coagulation efficiency, residual Al, and floc properties

Magnetic seeding coagulation (MSC) process has been used to accelerate flocs sedimentation with an applied magnetic field, offering large handling capacity and low energy consumption. The interactions of three typical Al species, aluminum chloride (AlCl₃), Al₁₃O₄(OH)₂₄⁷⁺ polymer (Al₁₃), and (AlO₄)₂Al₂₈(OH)₅₆¹⁸⁺ polymer (Al₃₀), with magnetic particles (MPs) were examined to clarify the MSC process. In traditional coagulation (TC) process, the aggregation of primary Al_a-dissolved organic matter (DOM) complexes with in-situ-formed polynuclear species generated a large average floc size (226 μm), which was proved to be efficient for DOC removal (52.6%). The weak connections between dissolved Al_a-DOM complexes and MPs led to the negligible changes of dissolved Al after seeding with MPs in AlCl₃. A significant interaction between MPs and Al₁₃ was observed, in which the MPs-Al₁₃-DOM complexes were proposed to be responsible for the significant improvement of DOC removal (from 47% to 52%) and residual total Al reduction (from 1.05 to 0.27 mg Al L^-1) with MPs addition. Al₃₀ produced a lower floc fractal dimension (D_f = 1.88) than AlCl₃ (2.08) and Al₁₃ (1.99) in the TC process, whereas its floc strength (70.9%) and floc recovery (38.5%) were higher than the others. Although more detached fragments were produced with MPs addition, the effective sedimentation of these fragments with the applied magnetic field led to the decrease of residual turbidity and colloidal Al in Al₃₀. The dependence of coagulation behavior to MPs and different Al species can be applied to guide the application of an effective MSC process.

Eco-friendly and enhanced colorimetric detection of aluminum ions using pectin-rich apple extract-based gold nanoparticles

Aluminum ions are very toxic to human health, especially in relation to neurodegenerative diseases. However, conventional methods of detecting such toxic ions suffer from the use of poisonous chemical probes and complex processes. Herein, we report an eco-friendly and enhanced colorimetric method of aluminum ion detection using green-synthesized gold nanoparticles (AuNPs) from apple (Malus domestica) extract. The apple extract-based AuNPs (AX-AuNPs) contain abundant pectin different from citrate-based AuNPs. The pectin-rich AX-AuNPs improved the sensitivity of the colorimetric detection of aluminum ions. The detection limit was about 20 μM both in artificial and drinking water-based real samples. Interestingly, it is turned out that the AX-AuNPs were aggregated naturally after the chemical assay because of solution getting decayed. For the environmental perspective, it was great that the lump of AX-AuNP aggregates could easily be removed from the solutions before solution discard. Overall, our results indicate that AX-AuNPs offer a high-selectivity, enhanced colorimetric detection of aluminum ions in a short time (less than 1 min), based on an eco-friend synthesis and disposal manner of AuNPs.

The REACH registration process: A case study of metallic aluminium, aluminium oxide and aluminium hydroxide

The European Union's REACH Regulation requires determination of potential health and environmental effects of chemicals in commerce. The present case study examines the application of REACH guidance for health hazard assessments of three high production volume (HPV) aluminium (Al) substances: metallic aluminium, aluminium oxide, and aluminium hydroxide. Among the potential adverse health consequences of aluminium exposure, neurotoxicity is one of the most sensitive targets of Al toxicity and the most critical endpoint. This case study illustrates integration of data from multiple lines of evidence into REACH weight of evidence evaluations. This case study then explains how those results support regulatory decisions on classification and labelling. Challenges in the REACH appraisal of Al compounds include speciation, solubility and bioavailability, application of assessment factors, read-across rationale and differences with existing regulatory standards. Lessons learned from the present case study relate to identification and evaluation of toxicologic and epidemiologic data; assessing data relevance and reliability; development of derived no-effect levels (DNELs); addressing data gaps and preparation of chemical safety reports.

Adaptable DNA-Interactive Probe Proficient at Selective Turn-On Sensing for Al3+: Insight from the Crystal Structure, Photophysical Studies, and Molecular Logic Gate

The synthesized Schiff base ligand 3-hydroxy-N'-(2-hydroxy-3-methoxybenzylidene)-2-naphthohydrazide (H₂NPV) is structurally characterized by single-crystal X-ray diffraction (XRD) and exhibits weak fluorescence in the excited state owing to the effect of excited-state-induced proton transfer (ESIPT). However, in the presence of Al³⁺, the ESIPT is blocked and chelation-enhanced fluorescence (CHEF) is induced because of complexation with the cations, resulting in turn-on emission for Al³⁺. The probe H₂NPV selectively detects Al³⁺ among the various metal ions, and the detection limit is found to be 1.70 μM. The composition and modes of complex coordination were determined by spectroscopic, theoretical studies and molecular logic gate applications. Finally, DNA binding studies were performed by spectroscopic and calorimetric methods to elucidate possible bioactivity of H₂NPV.

Adaptable DNA-Interactive Probe Proficient at Selective Turn-On Sensing for Al3+: Insight from the Crystal Structure, Photophysical Studies, and Molecular Logic Gate

The synthesized Schiff base ligand 3-hydroxy-N'-(2-hydroxy-3-methoxybenzylidene)-2-naphthohydrazide (H2NPV) is structurally characterized by single-crystal X-ray diffraction (XRD) and exhibits weak fluorescence in the excited state owing to the effect of excited-state-induced proton transfer (ESIPT). However, in the presence of Al3+, the ESIPT is blocked and chelation-enhanced fluorescence (CHEF) is induced because of complexation with the cations, resulting in turn-on emission for Al3+. The probe H2NPV selectively detects Al3+ among the various metal ions, and the detection limit is found to be 1.70 μM. The composition and modes of complex coordination were determined by spectroscopic, theoretical studies and molecular logic gate applications. Finally, DNA binding studies were performed by spectroscopic and calorimetric methods to elucidate possible bioactivity of H2NPV.

Click chemical assembly and validation of bio-functionalized superparamagnetic hybrid microspheres

Surface derivatized magnetic nanoparticles have been commonly used for magnetic separation. Facile mechanisms are needed to be developed for the design of bio-functionalized magnetic hybrid materials, where the surfaces can be re-generated for the re-use of the developed platforms. Superparamagnetic iron oxide nanoparticles with a diameter below 10 nm were synthesized via a novel microwave-assisted hydrothermal method in the presence of citrate ions, which allowed to obtain uniform and negatively charged nanoparticles. These were then coupled with Poly-l-lysine (PLL), forming micrometer-sized self-assembled spherical entities. Cross-linking the PLL within these microspheres with glutaraldehyde stabilized them chemically and mechanically. The active bio-functionality was introduced by a protein grafting methodology, using m-maleimidobenzoyl-N-hydroxysulfosuccinimide ester (SMBS). The Moringa oleifera Coagulant Protein (MOCP) from a seed extract was employed for its characteristic coagulation activity. The performance of the MOCP functionalized microspheres was evaluated as a function of turbidity removal of problematic colloidal clay from water via magnetic separation, resulting in over 80% of activity within 15 min. Surface of these hybrid materials can be re-generated by treatment with alcohol, allowing their easy magnetic separation and re-use. The rapid and strong response with tunable magnetic property makes these hybrid microspheres a powerful tool for many potential applications, due to the general applicability of the developed methodology.

Relationship between occupational aluminium exposure and histone lysine modification through methylation

BACKGROUND

Aluminium is an environmental neurotoxin to which human beings are extensively exposed. However, the molecular mechanism of aluminium toxicity remains unclear.

METHODS

The changes in cognitive function of aluminum exposed workers under long-term occupational exposure were evaluated, and the relationship between cognitive changes, plasma memory related BDNF and EGR1 protein expression, and variations of epigenetic markers H3K4me3, H3K9me2, H3K27me3 expression levels in blood was explored.

RESULTS

MMSE, DSFT, DST scores in cognitive function and the levels of plasma BDNF and EGR1 protein expression decreased with the increase of blood aluminum level. H3K4me3, H3K9me2, H3K27me3 expression levels in peripheral blood lymphocytes of aluminum exposed workers were statistically different (all P<0.05). H3K4me3, H3K9me2 and H3K27me3 expression levels in lymphocytes were correlated with blood aluminum level. BDNF, EGR1 protein level and H3K4me3, H3K9me2, H3K27me3 expression levels have different degrees of correlation. There was a linear regression relationship between plasma BDNF, H3K4me3 and H3K9me2. H3K9me2 had a greater effect on BDNF than H3K4me3. There is a linear regression relationship between EGR1, H3K4me3 and H3K27me3, and the influence of H3K4me3 on EGR1 is greater than that of H3K27me3 on EGR1.

CONCLUSION

Alummnum may regulate the expression of BDNF and EGR1 by regulating H3K4me3, H3K27me3 and H3K9me2, and affect the cognitive function of workers by affecting the expression of BDNF and EGR1.

Association between aluminum in drinking water and incident Alzheimer's disease in the Canadian Study of Health and Aging cohort

Epidemiological evidence linking aluminum in drinking water and Alzheimer's disease (AD) has been inconsistent, with previous studies often limited by small sample sizes. The present study addresses this issue using data from the Canadian Study of Health and Aging (CSHA), a prospective cohort of 10,263 subjects followed-up from 1991-1992 through 2001-2002. Participants' residential histories were linked to municipal drinking water sources in 35 Canadian municipalities to obtain ecologic pH, aluminum, fluoride, iron and silica concentrations in drinking water. Cox proportional hazards models were used to examine associations between aluminum and incident AD [Hazard Ratios (HRs), 95% confidence intervals (CIs)], adjusting for age, gender, history of stroke, education, and high blood pressure. A total of 240 incident AD cases were identified during follow-up of 3, 638 subjects derived from the CSHA cohort with complete data on all covariates. With categorical aluminum measurements, there was an increasing, but not statistically significant, exposure-response relationship (HR = 1.34, 95% CI 0.88-2.04, in the highest aluminum exposure category; p = 0.13 for linear trend). Similar results were observed using continuous aluminum measurements (HR=1.21, 95% CI 0.97-1.52, at the interquartile range of 333.8 μg/L; p = 0.09 for linear trend). In a subsample genotyped for ApoE-ε4, there was some evidence of an association between aluminum and AD (p = 0.03 for linear trend). Although a clear association between aluminum in drinking water and AD was not found, the linear trend observed in ApoE-ε4 subsample warrants further examination.

Amphoteric starch-based bicomponent modified soil for mitigation of harmful algal blooms (HABs) with broad salinity tolerance: Flocculation, algal regrowth, and ecological safety

The treatment of harmful algal blooms (HABs) by in-situ flocculation is an emerging technology capable of efficiently removing HABs from natural waters. However, differences in salinity, pH and algal species in freshwaters and seawaters can influence the flocculation treatment. In this study, we developed a bicomponent modified soil using amphoteric starch (AS) and poly-aluminium chloride (PAC) in order to effectively flocculate microalgae under broad salinity conditions. Specifically, the impacts of water salinity (0-3.3%), pH (3-11), and algal species (Microcystis aeruginosa and marine Chlorella sp.) were investigated in order to evaluate efficiency, dosage and mechanisms of algae flocculation. The results showed that AS-PAC modified soils possessed excellent resistance to salinity change due to the anti-polyelectrolyte effect of AS, which contributed to 99.9% removal efficiency of M. aeruginosa in fresh and saline waters, and Chlorella sp. in marine water, respectively. The dosage of the flocculant modifier was only 10-20% of that of another proven modifier (i.e. Moringa oleifera), which substantially reduced the material cost. The high salinity tolerance of algal flocculation by the AS-PAC modified soil was attributed to the synergistic processes of charge neutralization and netting-bridging. Thus, this study has developed a universal flocculant and revealed fundamental mechanisms for the mitigation of HABs under broad salinity conditions.

Multiplex SERS Chemosensing of Metal Ions via DNA-Mediated Recognition

The combination of molecular sensors and plasmonic materials is emerging as one of the most promising approaches for ultrasensitive SERS-based detection of metal ions in complex fluids. However, only a very small fraction of the large pool of potential chemosensors described in classical analytical chemistry has been successfully implemented into viable SERS platforms for metal ion determination. This is due to the molecular restrictions that require the chemosensor to adhere onto the plasmonic surface while retaining the capability to undergo large structural alterations upon metal ion binding. In this work, we demonstrate that the structural and functional plasticity of DNA for interacting with small aromatic molecules can be exploited to this end. DNA coating of silver nanoparticles modulates the interaction of the commercially available alizarin red S (ARS) chemosensor with the nanomaterial, translating its recognition capabilities from bulk solution onto the plasmonic surface, while simultaneously directing the particle assembling into highly efficient SERS clusters. The sensing approach was successfully applied to the multiplex, quantitative determination of Al(III) and Fe(III) in tap water in the subppb level.

Using fluorescence surrogates to track algogenic dissolved organic matter (AOM) during growth and coagulation/flocculation processes of green algae

Tracking the variation of the algogenic organic matter (AOM) released during the proliferation of green algae and subsequent treatment processes is crucial for constructing and optimizing control strategies. In this study, the potential of the spectroscopic tool was fully explored as a surrogate of AOM upon the cultivation of green algae and subsequent coagulation/flocculation (C/F) treatment processes using ZrCl₄ and Al₂(SO₄)₃. Fluorescence excitation emission matrix coupled with parallel factor analysis (EEM-PARAFAC) identified the presence of three independent fluorescent components in AOM, including protein-like (C1), fulvic-like (C2) and humic-like components (C3). Size exclusion chromatography (SEC) revealed that C1 in AOM was composed of large-sized proteins and aromatic amino acids. The individual components exhibited their unique characteristics with respect to the dynamic changes. C1 showed the highest correlation with AOM concentrations (R² = 0.843) upon the C/F processes. C1 could also be suggested as an optical predictor for the formation of trihalomethanes upon the C/F processes. This study sheds a light for the potential application of the protein-like component (C1) as a practical surrogate to track the evolution of AOM in water treatment or wastewater reclamation systems involving Chlorella vulgaris green algae.

Human health risk associated with the management of phosphorus in freshwaters using lanthanum and aluminium

The use of geo-engineering materials to manage phosphorus in lakes has increased in recent years with aluminium and lanthanum based materials being most commonly applied. Hence the potential impact of the use of these compounds on human health is receiving growing interest. This review seeks to understand, evaluate and compare potential unintended consequences on human health and ecotoxicological risks associated with the use of lanthanum- and aluminium-based materials to modify chemical and ecological conditions in water bodies. In addition to their therapeutic use for the reduction of intestinal phosphate absorption in patients with impaired renal function, the phosphate binding capacity of aluminium and lanthanum also led to the development of materials used for water treatment. Although lanthanum and aluminium share physicochemical similarities and have many common applications, their uptake and kinetics within the human body and living organisms importantly differ from each other which is reflected in a different toxicity profile. Whilst a causal role in the development of neurological pathologies, skeletal lesions, hematopoietic disorders and respiratory effects has unequivocally been demonstrated with increased exposure to aluminium, studies until now have failed to find such a clear association after exposure to lanthanum although caution is warranted. Our review indicates that lanthanum and aluminium have a distinctly different profile with respect to their potential effects on human health. Regular monitoring of both aluminium and lanthanum concentrations in lanthanum-/aluminium-treated water by the responsible authorities is recommended to avoid acute accidental or chronic low level accumulation.

An excellent example illustrating the fluorescence sensing property of cobalt–organic frameworks

A cobalt–organic framework senses metal ions via fluorescence enhancement and quenching based on exposed pyridyl and carboxyl functional sites.

Transcriptome-wide analysis of MADS-box family genes involved in aluminum and fluoride assimilation in Camellia sinensis

MADS-box transcription factors (TFs) are involved in a variety of processes in flowering plants ranging from root growth to flower and fruit development. However, studies of the tolerance-related functions of MADS-box genes are very limited, and to date no such studies have been conducted on Camellia sinensis. To gain insight into the functions of genes of this family and to elucidate the role they may play in tissue development and Al and F response, we identified 45 MADS-box genes through transcriptomic analysis of C. sinensis. Phylogenetic analysis of these CsMADS-box genes, along with their homologues in Arabidopsis thaliana, enabled us to classify them into distinct groups, including: M-type (Mα), MIKC* and MIKC^c (which contains the SOC1, AGL12, AGL32, SEP, ANR1, SVP, and FLC subgroups). Conserved motif analysis of the CsMADS-box proteins revealed diverse motif compositions indicating a complex evolutionary relationship. Finally, we examined the expression patterns of CsMADS-box genes in various tissues and under different Al and F concentration treatments. Our qPCR results showed that these CsMADS-box genes were involved in Al and F accumulation and root growth in C. sinensis. These findings lay the foundation for future research on the function of CsMADS-box genes and their role in response to Al and F accumulation in root tissues.

Decolorization of reactive dye Remazol Brilliant Blue R by zirconium oxychloride as a novel coagulant: optimization through response surface methodology

The aim of the present study was to investigate the performance of a novel coagulant, i.e. ZrOCl₂, for the removal of anthraquinone-based reactive dye from aqueous solution. An ideal experimental setup was designed based on central composite design using response surface methodology to determine the individual and interactive effects of different operational variables (i.e. pH, coagulant dose and dye concentration) on treatment performance in terms of dye and chemical oxygen demand (COD) removal efficiencies. Total 92.58% dye and 85.33% COD removal were experimentally attained at optimized conditions at low coagulant dose, i.e. 156.67 mg/L for the dye concentration of 105.67 mg/L at pH 2. To validate the working pH of the metal coagulant, the static charge of ZrOCl₂ was measured using Eh value. The performance of the coagulant was validated with experimental and predicted values in the selected data set, and R² values for both responses were found to be 0.99 and 0.95 respectively, which shows the reliability of the experimental design. Further, the toxicity of the coagulant was assessed and no such toxicity was found even up to the concentration of 500 mg/L, proclaiming the disposal of sludge may not exhibit any threat to humans. Experimental results suggested that the ZrOCl₂ could be used as an eco-friendly coagulant for dye wastewater treatment.

Size-Dependent Neurotoxicity of Aluminum Oxide Particles: a Comparison Between Nano- and Micrometer Size on the Basis of Mitochondrial Oxidative Damage

Aluminum nanoparticles (AlNPs) are among the most abundantly produced nanosized particles in the market. There is limited information about the potential harmful effects of aluminum oxide due to its particle size on human health. Considering the toxic effects of Al on brain as its target tissue, in this study, the toxicity of nanoparticles, microparticles, and ionic forms of Al on rat brain and isolated mitochondria was evaluated. Sixty male Wistar rats were divided into ten groups (six rats each), in which group I was the control, and the other groups were administered different doses of Al nanoparticles, Al microparticles (AlMP), and Al ionic forms (2, 4, and 8 mg/kg, i.p.) for 28 days. After 24 h, the animals were killed, brain tissue was separated, the mitochondrial fraction was isolated, and oxidative stress markers were measured. Also, mitochondrial function was assayed by MTT test. The results showed that all forms of Al particles induced ROS formation, lipid peroxidation, protein oxidation, glutathione depletion, mitochondrial dysfunction, and gait abnormalities in a dose-dependent manner. In addition, Al particles decreased mitochondrial membrane potential. These data indicated that oxidative stress might contribute to the toxicity effects of Al. Comparison of oxidative stress markers between all forms of Al revealed that the toxic effect of AlNP on brain tissue was substantially more than that caused by AlMP and bulk form. This study showed more neurotoxicity of AlNPs compared to other forms on brain oxidative damage that probably is due to more penetration into the brain.

Aluminium oxide nanoparticles compromise spatial learning and memory performance in rats

Recently, the biosafety and potential influences of nanoparticles on central nervous system have received more attention. In the present study, we assessed the effect of aluminium oxide nanoparticles (Al2O3-NPs) on spatial cognition. Male Wistar rats were intravenously administered Al2O3-NP suspension (20 mg/kg body weight/day) for four consecutive days, after which they were assessed. The results indicated that Al2O3-NPs impaired spatial learning and memory ability. An increment in malondialdehyde levels with a concomitant decrease in superoxide dismutase activity confirmed the induction of oxidative stress in the hippocampus. Additionally, our findings showed that exposure to Al2O3-NPs resulted in decreased acetylcholinesterase activity in the hippocampus. Furthermore, Al2O3-NPs enhanced aluminium (Al) accumulation and disrupted mineral element homoeostasis in the hippocampus. However, they did not change the morphology of the hippocampus. Our results show a connection among oxidative stress, disruption of mineral element homoeostasis, and Al accumulation in the hippocampus, which leads to spatial memory deficit in rats treated with Al2O3-NPs.

Safety Assessment of Alumina and Aluminum Hydroxide as Used in Cosmetics

This is a safety assessment of alumina and aluminum hydroxide as used in cosmetics. Alumina functions as an abrasive, absorbent, anticaking agent, bulking agent, and opacifying agent. Aluminum hydroxide functions as a buffering agent, corrosion inhibitor, and pH adjuster. The Food and Drug Administration (FDA) evaluated the safe use of alumina in several medical devices and aluminum hydroxide in over-the-counter drugs, which included a review of human and animal safety data. The Cosmetic Ingredient Review (CIR) Expert Panel considered the FDA evaluations as part of the basis for determining the safety of these ingredients as used in cosmetics. Alumina used in cosmetics is essentially the same as that used in medical devices. This safety assessment does not include metallic or elemental aluminum as a cosmetic ingredient. The CIR Expert Panel concluded that alumina and aluminum hydroxide are safe in the present practices of use and concentration described in this safety assessment.

Overview of the Relationship Between Aluminum Exposure and Health of Human Being

Aluminum is a type of ubiquitously existing naturally and widely used metal in our world. It is combined with other elements and forms different compounds. In different pH and due to other conditions, it can be released into ions of different valence states. Our century is an "aluminum age"; aluminum is used in many fields of our daily life, such as vaccine adjuvant, antacids, food additives, skin care products, cosmetics, and cooking wares, and may be as elements or contaminants appeared in a lot of foods, including infant formulae, milk products, juice, wine, sea foods, and tea. It also appears in drinking water due to the water treatment process, or naturally coming from weathering rocks and soils, or released from rocks and soils caused by pollution-induced acid rain. Due to good physical and chemical property, aluminum is being tremendously utilized in many industries. In a lot of production and process procedures, aluminum particulates are seriously exposed by workers. Many factors, such as silicon, citrate, iron, calcium, fluoride, etc., can affect absorption of aluminum in human body. Human being ingests aluminum through the respiratory and digestive system and skin. Aluminum can affect our health, especially impair central nervous system. The important damage is cognitive impairment in Al-exposed peoples, Alzheimer's disease and other neurodegenerative disorders have been related with aluminum exposure, and aluminum has been proposed as etiology.

Hydrazinopyrimidine derived novel Al3+ chemosensor: molecular logic gate and biological applications

For the first time, a hydrazinopyrimidine based chemosensor has been designed for sensing Al³⁺ through CHEF-PET-ESIPT fluorescence mechanisms and by building an ‘INHIBIT’ molecular logic gate.