Natural background levels and driving factors of aluminum in shallow groundwater of an urbanized delta: Insight from eliminating anthropogenic-impacted groundwaters.

Knowledge on natural background levels (NBLs) of aluminum (Al) in groundwater can accurately assess groundwater Al contamination at a regional scale. However, it has received little attention. This study used a combination of preselection and statistic methods consisting of the oxidation capacity and the boxplot iteration methods to evaluate the NBL of shallow groundwater Al in four groundwater units of the Pearl River Delta (PRD) via eliminating anthropogenic-impacted groundwaters and to discuss driving factors controlling high NBLs of Al in groundwater in this area. A total of 280 water samples were collected, and 18 physico-chemical parameters including Redox potential, dissolved oxygen, pH, total dissolved solids, HCO3 -, NH4 +, NO3 -, SO4 2-, Cl-, NO2 -, F-, K+, Na+, Ca2+, Mg2+, Fe, Mn, and Al were analyzed. Results showed that groundwater Al NBLs in groundwater units A-D were 0.11, 0.16, 0.15, and 0.08 mg/L, respectively. The used method in this study is acceptable for the assessment of groundwater Al NBLs in the PRD, because groundwater Al concentrations in various groundwater units in residual datasets were independent of land-use types, but they were opposite in the original datasets. The dissolution of Al-rich minerals in sediments/rocks was the major source for groundwater Al NBLs in the PRD, and the interaction with Al-rich river water was secondary one. The high groundwater Al NBL in groundwater unit B was mainly attributed to the acid precipitation and the organic matter mineralization inducing the release of Al in Quaternary sediments. By contrast, the high groundwater Al NBL in groundwater unit C mainly was ascribed to the release of Al complexes such as fluoroaluminate from rocks/soils into groundwater induced by acid precipitation, but it was limited by the dissolution of Mg minerals (e.g., dolomite) in aquifers. This study provides not only useful groundwater Al NBLs for the evaluation of groundwater Al contamination but also a reference for understanding the natural geochemical factors controlling groundwater Al in urbanized deltas such as the PRD. PRACTITIONER POINTS: The natural background level (NBL) of groundwater aluminum in the Pearl River Delta (PRD) was evaluated. The dissolution of aluminum-rich minerals in sediments/rocks was the major source for groundwater aluminum NBLs in the PRD. The acid precipitation and organic matter mineralization contribute to high groundwater Al NBL in the groundwater unit B. The acid precipitation contributes to high groundwater Al NBL in the groundwater unit C, while dissolution of magnesium minerals limits it.

Vertical transport velocity of fine particles of aluminum smelter emissions.

In this study, the average values of vertical velocity of particles emitted from an aluminum smelter in the surface layer of the atmosphere were estimated using a semi-empirical method. The method is based on regression analysis of the horizontal profile of pollutants measured along the selected direction using moss bioindicators. The selection of epiphytic mosses Sanionia uncinata was carried out in 2013 in the zone of influence of a metallurgical industry enterprise in the city of Kandalaksha, Murmansk region. The concentrations of As, Si, Ni, Zn, Ti, Cd, Na, Pb, Co, K, Ba, Ca, Mg, Mn, Sr, Fe, Al, V, Cr, Cu were determined using atomic emission spectrometry. The conducted assessments showed that the average particle velocity toward the Earth's surface, when considering large spatial and temporal scales, is tens of times higher than gravitational settling velocities.

Development of underground detection system using a metal detector and aluminum tag for, Copris ochus (Coleoptera: Scarabaeidae).

Tracking of soil-dwelling insects poses greater challenges compared to aboveground-dwelling animals in terrestrial systems. A metal detector system consisting of a commercially available detector and aluminum tags was developed for detecting dung beetle, Copris ochus Motschulsky (Coleoptera: Scarabaeidae). First, detection efficacy of the system was evaluated by varying volumes of aluminum tags attached on a plastic model of the insect and also by varying angles. Then, detection efficacy was evaluated by varying depths of aluminum-tagged models under soil in 2 vegetation types. Finally, the effects of tag attachment on C. ochus adults were assessed for survivorship, burrowing depth, and horizontal movement. Generally, an increase in tag volume resulted in greater detection distance in semi-field conditions. Maximum detection distance of aluminum tag increased up to 17 cm below soil surface as the tag size (0.5 × 1.0 cm [width × length]) and thickness (16 layers) were maximized, resulting in a tag weight of 31.4 mg, comprising ca. 9% of average weight of C. ochus adult. Furthermore, the detection efficacy did not vary among angles except for 90°. In the field, metal detectors successfully detected 5 aluminum-tagged models in 20 × 10 m (W × L) arena within 10 min with detection rates ≥85% for up to depth of 10 cm and 45%-60% at depth of 20 cm. Finally, aluminum tagging did not significantly affect survivorship and behaviors of C. ochus. Our study indicates the potential of metal detector system for tracking C. ochus under soil.

Seasonal studies of aquatic humic substances from Amazon rivers: characterization and interaction with Cu (II), Fe (II), and Al (III) using EEM-PARAFAC and 2D FTIR correlation analyses.

Aquatic humic substances (AHS) are defined as an important components of organic matter, being composed as small molecules in a supramolecular structure and can interact with metallic ions, thereby altering the bioavailability of these species. To better understand this behavior, AHS were extracted and characterized from Negro River, located near Manaus city and Carú River, that is situated in Itacoatiara city, an area experiencing increasing anthropogenic actions; both were characterized as blackwater rivers. The AHS were characterized by 13C nuclear magnetic ressonance and thermochemolysis GC-MS to obtain structural characteristics. Interaction studies with Cu (II), Al (III), and Fe (III) were investigated using fluorescence spectroscopy applied to parallel factor analysis (PARAFAC) and two-dimensional correlation spectroscopy with Fourier transform infrared spectroscopy (2D-COS FTIR). The AHS from dry season had more aromatic fractions not derived from lignin and had higher content of alkyls moities from microbial sources and vegetal tissues of autochthonous origin, while AHS isolated in the rainy season showed more metals in its molecular architecture, lignin units, and polysacharide structures. The study showed that AHS composition from rainy season were able to interact with Al (III), Fe (III), and Cu (II). Two fluorescent components were identified as responsible for interaction: C1 (blue-shifted) and C2 (red-shifted). C1 showed higher complexation capacities but with lower complexation stability constants (KML ranged from 0.3 to 7.9 × 105) than C2 (KML ranged from 3.1 to 10.0 × 105). 2D-COS FTIR showed that the COO- and C-O in phenolic were the most important functional groups for interaction with studied metallic ions.

Multi-ion detection chemosensor based on rhodamine for turn-on fluorescence sensing and bioimaging of Fe3+, Al3+, Cr3+, and Hg2+ under different channels.

A novel rhodamine-based multi-ion fluorescent sensor, RGN, was designed and synthesized for the highly selective detection of mercury ions (Hg2+) in ethanol and water systems, as well as trivalent cations (Fe3+, Al3+, and Cr3+) in acetonitrile and water systems using a two-step Schiff base reaction method. Nuclear magnetic titration experiments and theoretical calculations demonstrated that the sensor achieved the detection of the aforementioned metal ions through the fluorescence turn-on phenomenon induced by lactam ring-opening. Density functional theory (DFT) calculation results showed decreased HOMO-LUMO energy gaps and increased dipole moments, indicating the effective coordination of the sensor with the corresponding metal ions to form more stable complexes, thereby achieving detection objectives. Furthermore, the fluorescence turn-on sensor RGN exhibited relatively low detection limits, with limits of detection (LOD) for Fe3+, Al3+, Cr3+, and Hg2+ being 10.20 nM, 14.66 nM, 58.78 nM, and 73.33 nM, respectively. Finally, practical applications of sensor RGN in environmental water samples, L929 cells, and zebrafish were demonstrated, indicating its potential for detecting and tracking Fe3+, Al3+, Cr3+, and Hg2+ in environmental samples and biological systems, with prospects for biomedical applications in the diagnosis and treatment of heavy metal ion-induced diseases.

Aluminum zirconate nanoparticles in etch and rinse adhesive to caries affected dentine: An in-vitro scanning electron microscopy, elemental distribution, antibacterial, degree of conversion and micro-tensile bond strength assessment.

To incorporate different concentrations of Al2O9Zr3 (1%, 5%, and 10%) nanoparticles (NP) into the ER adhesive and subsequently assess the impact of this addition on the degree of conversion, µTBS, and antimicrobial efficacy. The current research involved a wide-ranging examination that merged various investigative techniques, including the application of scanning electron microscopy (SEM) for surface characterization of NP coupled with energy-dispersive x-ray spectroscopy (EDX), Fourier-transform infrared (FTIR) spectroscopy, µTBS testing, and microbial analysis. Teeth were divided into four groups based on the application of modified and unmodified three-step ER adhesive primer. Group 1 (0% Al2O9Zr3 NPs) Control, Group 2 (1% Al2O9Zr3 NPs), Group 3 (5% Al2O9Zr3 NPs), and Group 4 (10% Al2O9Zr3 NPs). EDX analysis of Al2O9Zr3 NPs was performed showing elemental distribution in synthesized NPs. Zirconium (Zr), Aluminum (Al), and Oxides (O2). After primer application, an assessment of the survival rate of Streptococcus mutans was completed. The FTIR spectra were analyzed to observe the characteristic peaks indicating the conversion of double bonds, both before and after the curing process, for the adhesive Etch and rinse containing 1,5,10 wt% Al2O9Zr3 NPs. µTBS and failure mode assessment were performed using a Universal Testing Machine (UTM) and stereomicroscope respectively. The µTBS and S.mutans survival rates comparison among different groups was performed using one-way ANOVA and Tukey post hoc (p = .05). Group 4 (10 wt% Al2O9Zr3 NPs + ER adhesive) specimens exhibited the minimum survival of S.mutans (0.11 ± 0.02 CFU/mL). Nonetheless, Group 1 (0 wt% Al2O9Zr3 NPs + ER adhesive) displayed the maximum surviving S.mutans (0.52 ± 0.08 CFU/mL). Moreover, Group 2 (1 wt% Al2O9Zr3 NPs + ER adhesive) (21.22 ± 0.73 MPa) samples displayed highest µTBS. However, the bond strength was weakest in Group 1 (0 wt% Al2O9Zr3 NPs + ER adhesive) (14.13 ± 0.32 MPa) study samples. The etch-and-rinse adhesive exhibited enhanced antibacterial activity and micro-tensile bond strength (µTBS) when 1% Al2O9Zr3 NPs was incorporated, as opposed to the control group. Nevertheless, the incorporation of Al2O9Zr3 NPs led to a decrease in DC. RESEARCH HIGHLIGHTS: 10 wt% Al2O9Zr3 NPs + ER adhesive specimens exhibited the minimum survival of S.mutans. 1 wt% Al2O9Zr3 NPs + ER adhesive samples displayed the most strong composite/CAD bond. The highest DC was observed in Group 1: 0 wt% Al2O9Zr3 NPs + ER adhesive.

LCA of recycling aluminium incineration bottom ash, dross and shavings in a rotary furnace and environmental benefits of salt-slag valorisation.

Recycling aluminium in a rotary furnace with salt-fluxes allows recovering valuable alloys from hard-to-recycle waste/side-streams such as packaging, dross and incinerator bottom ash. However, this recycling route generates large amounts of salt-slag/salt-cake hazardous wastes which can pose critical environmental risks if landfilled. To tackle this issue, the metallurgical industry has developed processes to valorise the salt-slag residues into recyclable salts and aluminium concentrates, while producing by-products such as ammonium sulphate and non-metallic compounds (NMCs), with applications in the construction or chemical industries. This study aims to assess through LCA the environmental impacts of recycling aluminium in rotary furnaces for both salt-slag management routes: valorisation or landfill. It was found that this recycling process brings forth considerable net environmental profits, which increase for all the considered impact categories if the salt-slag is valorised. The main benefits arise from the production of secondary cast aluminium alloys, which is not unexpected due to the high energy intensity of aluminium primary production. However, the LCA results also identify other hotspots which play a significant role, and which should be considered for the optimisation of the process based on its environmental performance, such as the production of by-products, the consumption of energy/fuels and the avoidance of landfilling waste. Additionally, the assessment shows that the indicators for mineral resource scarcity, human carcinogenic toxicity and terrestrial ecotoxicity are particularly benefited by the salt-slag valorisation. Finally, a sensitivity analysis illustrates the criticality of the metal yield assumptions when calculating the global warming potential of aluminium recycling routes.

Ultrasensitive detection of chloramphenicol in water using functionalized polymers with an aluminium organic framework.

Metal-Organic Frameworks (MOFs) are extensively used as electrode material in various sensing applications due to their efficacious porous nature and tunable properties. However, pristine MOFs lack conductive attributes that hinder their wide usage in electrochemical applications. Electropolymerization of several aromatic monomers has been a widely used strategy for preparing conducting electrode materials for various sensing applications in the past decades. Herein, we report a similar approach by employing the electropolymerization method to create a functional polymer layer to enhance the sensitivity of an Aluminium Organic Framework (DUT-4) for the selective detection of Chloramphenicol (CAP) antibiotic in aqueous environment. The combined strategy using the conducting polymer layer with the porous Al MOF provides surpassing electrochemical performance for sensing CAP with regard to the very low detection limit (LOD = 39 nM) and exceptionally high sensitivity (11943 µA mM-1 cm-2). In addition, the fabricated sensor exhibited good selectivity, reproducibility and stability. The developed method was successfully evaluated in various real samples including lake water and river water for CAP detection with good recovery percentages even at lower concentrations.

[Determination of 24 elements migration in Yixing clay pottery by inductively coupled plasma mass spectrometry].

OBJECTIVE: To establish an analytical method for determining the migration of 24 elements in Yixing clay pottery in 4% acetic acid simulated solution by inductively coupled plasma mass spectrometry. METHODS: Four types of Yixing clay pottery, including Yixing clay teapot, Yixing clay kettle, Yixing clay pot, and Yixing clay electric stew pot, were immersed in 4% acetic acid as a food simulant for testing. The migration amount of 24 elements in the migration solution was determined using inductively coupled plasma mass spectrometry. RESULTS: Lithium, magnesium, aluminum, iron, and barium elements with a mass concentration of 1000 µg/L; Lead, cadmium, total arsenic, chromium, nickel, copper, vanadium, manganese, antimony, tin, zinc, cobalt, molybdenum, silver, beryllium, thallium, titanium, and strontium elements within 100 µg/L there was a linear relationship within, the r value was between 0.998 739 and 0.999 989. Total mercury at 5.0 µg/L, there was a linear relationship within, the r value of 0.995 056. The detection limit of the elements measured by this method was between 0.5 and 45.0 µg/L, the recovery rate was 80.6%-108.9%, and the relative standard deviation was 1.0%-4.8%(n=6). A total of 32 samples of four types of Yixing clay pottery sold on the market, including teapots, boiling kettles, casseroles, and electric stewing pots, were tested. It was found that the migration of 16 elements, including beryllium, titanium, chromium, nickel, cobalt, zinc, silver, cadmium, antimony, total mercury, thallium, tin, copper, total arsenic, molybdenum, and lead, were lower than the quantitative limit. The element with the highest migration volume teapot was aluminum, magnesium, and barium; The kettle was aluminum and magnesium; Casserole was aluminum, magnesium, and lithium; The electric stew pot was aluminum. CONCLUSION: This method is easy to operate and has high accuracy, providing an effective and feasible detection method for the determination and evaluation of element migration in Yixing clay pottery.

Complexation mechanism of Pb2+ on Al-substituted hematite: A modeling study and theoretical calculation.

Hematite nanoparticles commonly undergoes isomorphic substitution of Al3+ in nature, while how the Al-substitution-induced morphological change, defective structure and newly generated Al-OH sites affect the adsorption behavior of hematite for contaminants remains poorly understood. Herein, the interfacial reactions between Al-substituted hematite and Pb2+ was investigated via CD-MUSIC modeling and DFT calculations. As the Al content increased from 0% to 9.4%, Al-substitution promoted the proportion of (001) facets and caused Fe vacancies on hematite, which increased the total active site density of hematite from 5.60 to 17.60 sites/nm2. The surface positive charge of hematite significantly increased from 0.096 to 0.418 C/m2 at pH 5.0 due to the increases in site density and proton affinity (logKH) of hematite under Al-substitution. The adsorption amount of hematite for Pb2+ increased from 3.92 to 9.74 mmol/kg at pH 5.0 and 20 µmol/L initial Pb2+ concentration with increasing Al content. More Fe vacancies may lead to a weaker adsorption energy (Ead) of hematite for Pb2+, while the Ead was enhanced at higher Al content. The adsorption affinity (logKPb) of bidentate Pb complexes slightly increased while that of tridentate Pb complexes decreased with increasing Al content due to the presence of ≡ AlOH-0.5 and ≡ Fe2AlO-0.5 sites. Tridentate Pb complexes were dominant species on the surface of pure hematite, while bidentate ones became more dominant with increasing Al content. The obtained model parameters and molecular scale information are of great importance for better describing and predicting the environmental fate of toxic heavy metals in terrestrial and aquatic environments.

Evaluate the aluminum concentrations in whey milk samples of cows from different areas using deep eutectic solvent-based ultrasound-assisted dispersive liquid-liquid microextraction method.

This study investigates the contamination of cow milk with aluminum (Al) and its potential health implications, particularly for children. Cow milk samples were collected from both nonexposed and exposed areas in Sindh, based on the source of livestock drinking water (fresh canals and groundwater). An environmental friendly deep eutectic solvent (DES) was used with ultrasonic-assisted dispersive liquid-liquid microextraction (UDLLµE) to enrich trace amounts of Al in whey milk and water samples. The enriched samples were then analyzed using inductively coupled plasma optical emission spectrometry. Certified reference materials were employed to validate the methodology, and the experimental results exhibited acceptable conformity. The DES-based dispersive liquid-liquid microextraction method was environmental friendly, devoid of acids and oxidizing agents, and used safe and inexpensive components for routine trace metal analysis in diverse samples. The resulting data revealed that Al in whey milk samples was observed in the range of 31-45 %, corresponding to (160-270) µg L-1 and (700-1035) µg L-1 in nonexposed and exposed whole cow milk samples, respectively. Additionally, it was observed that milk boiling in Al utensil for 10-20 min enhanced the Al levels from 3 to 8% of its total contents in milk samples.

Assessing the health risks of heavy metals and seasonal minerals fluctuations in Camellia sinensis cultivars during their growth seasons.

The risk assessment of heavy metals in tea is extremely imperative for the health of tea consumers. However, the effects of varietal variations and seasonal fluctuations on heavy metals and minerals in tea plants remain unclear. Inductively coupled plasma optical emission spectrometry (ICP-OES) was used to evaluate the contents of aluminum (Al), manganese (Mn), magnesium (Mg), boron (B), calcium (Ca), copper (Cu), cobalt (Co), iron (Fe), sodium (Na), zinc (Zn), arsenic (As), cadmium (Cd), chromium (Cr), nickel (Ni), and antimony (Sb) in the two categories of young leaves (YL) and mature leaves (ML) of tea (Camellia sinensis) cultivars throughout the growing seasons. The results showed significant variations in the contents of the investigated nutrients both among the different cultivars and growing seasons as well. Furthermore, the average concentrations of Al, Mn, Mg, B, Ca, Cu, Co, Fe, Na, Zn, As, Cd, Cr, Ni, and Sb in YL ranged, from 671.58-2209.12, 1260.58-1902.21, 2290.56-2995.36, 91.18-164.68, 821.95-5708.20, 2.55-3.80, 3.96-25.22, 37.95-202.84, 81.79-205.05, 27.10-69.67, 0.028-0.053, 0.065-0.127, 2.40-3.73, 10.57-12.64, 0.11-0.14 mg kg-1, respectively. In ML, the concentrations were 2626.41-7834.60, 3980.82-6473.64, 3335.38-4537.48, 327.33-501.70, 9619.89-13153.68, 4.23-8.18, 17.23-34.20, 329.39-567.19, 145.36-248.69, 40.50-81.42, 0.089-0.169, 0.23-0.27, 5.24-7.89, 18.51-23.97, 0.15-0.19 mg kg-1, respectively. The contents of all analyzed nutrients were found to be higher in ML than in YL. Target hazard quotients (THQ) of As, Cd, Cr, Ni, and Sb, as well as the hazard index (HI), were all less than one, suggesting no risk to human health via tea consumption. This research might provide the groundwork for essential minerals recommendations, as well as a better understanding and management of heavy metal risks in tea.

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.

Development of a water-soluble fluorescent Al3+ probe based on phenylsulfonyl-2-pyrone in biological systems.

BACKGROUND: Al exists naturally in the environment and is an important component in acidic soils, which harm almost all plants. Furthermore, Al is widely used in food additives, cosmetics, and medicines, resulting in living organisms ingesting traces of Al orally or dermally every day. Accordingly, Al accumulates in the body, which can cause negative bioeffects and diseases, and this concern is gaining increasing attention. Therefore, to detect and track Al in the environment and in living organisms, the development of novel Al-selective probes that are water-soluble and exhibit fluorescence at long wavelengths is necessary. RESULTS: In this study, an Al3+-selective fluorescent probe PSP based on a novel pyrone molecule was synthesized and characterized to detect and track Al in biological systems. PSP exhibited fluorescence enhancement at 580 nm in the presence of Al3+ in aqueous media. Binding analysis using Job's plot and structural analysis using 1H NMR showed that PSP formed a 1:1 complex with Al3+ at the two carbonyl groups of the dimethyl malonate of the pyrone ring. Upon testing in biological systems, PSP showed good cell membrane permeability, detected intracellular Al3+ in human breast cancer cells (MDA-MB-231), and successfully imaged accumulated Al3+ in Microcystis aeruginosa and the larvae of Rheocricotopus species. SIGNIFICANCE: The novel Al3+-selective fluorescent probe PSP is highly effective and is expected to aid in elucidating the role of Al3+ in the environment and living organisms.

Trace metals and nutrient analysis of marine fish species from the Gwadar coast.

Trace metals are naturally occurring metals found in very small concentrations in the environment. In the context of fish flesh, metals such as copper, calcium, potassium, sodium, zinc, iron, and manganese are absorbed by fish and play vital roles in various physiological functions. However, if these metals exceed the recommended limits set by WHO/FAO, they are termed 'toxic metals' due to their harmful impacts on both the fish and its consumers. Therefore, the present study aims to analyze the levels of protein, lipids, and certain metals-Aluminum (Al), Sodium (Na), Zinc (Zn), Titanium (Ti), Iron (Fe), Copper (Cu), Potassium (K), and Calcium (Ca) in three commercially important marine fishes i.e. Rastrelliger kanagurta, Sardinella abella, and Otolithes ruber. The study also aims to assess their potential impact on human health. The macro-Kjeldhal method and Soxhlet apparatus were used to estimate protein and lipid contents, while atomic absorption spectroscopy (AAS) was used to estimate trace metals found in fishes. The study found that these fish species are valuable sources of protein, lipids, and certain essential minerals. The protein content (CP) in these three species ranged from 63.35 to 86.57%, while lipid content was from 21.05 to 23.86%. The overall results of the trace metal concentrations analyzed in the present study revealed that Aluminum (Al), Sodium (Na), Zinc (Zn), Titanium (Ti), Copper (Cu), Potassium (K), and Calcium (Ca) were found in low concentration or traces and also within suitable ranges as set by WHO/FAO. However, Iron (Fe) was absent in all three species. Moreover, both copper and potassium were found in all three species, while Zinc was present in Rastrelliger kanagurta and Sardinella abella, calcium in Sardinella abella, and sodium in Otolithes ruber only. Titanium was recorded for the first time in S. abella. However, the total health risk assessment associated with these fish food consumption was measured by THQ and TTHQ and found to be less than 1, which shows no potential risk related to trace metals found in these fishes on human health upon their consumption. In conclusion, these commercially important marine fish species were found valuable sources of protein, lipids, and essential trace minerals that are necessary for human health. Thus, the current study provides useful information for the local population to make informed decisions about their daily diets and highlights the importance of sustainable fishing practices to maintain these valuable marine resources by periodical monitoring of their ecosystem.

External aluminium supply regulates photosynthesis and carbon partitioning in the Al-accumulating tropical shrub Melastoma malabathricum.

Aluminium (Al) is toxic to most plants, but recent research has suggested that Al addition may stimulate growth and nutrient uptake in some species capable of accumulating high tissue Al concentrations. The physiological basis of this growth response is unknown, but it may be associated with processes linked to the regulation of carbon assimilation and partitioning by Al supply. To test alternative hypotheses for the physiological mechanism explaining this response, we examined the effects of increasing Al concentrations in the growth medium on tissue nutrient concentrations and carbon assimilation in two populations of the Al-accumulator Melastoma malabathricum. Compared to seedlings grown in a control nutrient solution containing no Al, mean rates of photosynthesis and respiration increased by 46% and 27%, respectively, total non-structural carbohydrate concentrations increased by 45%, and lignin concentration in roots decreased by 26% when seedlings were grown in a nutrient solution containing 2.0 mM Al. The concentrations of P, Ca and Mg in leaves and stems increased by 31%, 22%, and 26%, respectively, in response to an increase in nutrient solution Al concentration from 0 to 2.0 mM. Elemental concentrations in roots increased for P (114%), Mg (61%) and K (5%) in response to this increase in Al concentration in the nutrient solution. Plants derived from an inherently faster-growing population had a greater relative increase in final dry mass, net photosynthetic and respiration rates and total non-structural carbohydrate concentrations in response to higher external Al supply. We conclude that growth stimulation by Al supply is associated with increases in photosynthetic and respiration rates and enhanced production of non-structural carbohydrates that are differentially allocated to roots, as well as stimulation of nutrient uptake. These responses suggest that internal carbon assimilation is up-regulated to provide the necessary resources of non-structural carbohydrates for uptake, transport and storage of Al in Melastoma malabathricum. This physiological mechanism has only been recorded previously in one other plant species, Camellia sinensis, which last shared a common ancestor with M. malabathricum more than 120 million years ago.

New materials-based on gelatin coordinated with zirconium or aluminum for ecological retanning.

Ecological retanning agent is an effective way to solve the pollution source of leather manufacturing industry. In this study, the gelatin from chrome-containing leather shavings in the leather industry was used to realize sustainable leather post-tanning. The gelatin hydrolysate (GH) coordinated with Zr4+ or Al3+ to prepare eco-friendly retanning agents GH-Zr and GH-Al. The successful coordination between GH and metal ions was characterized by FTIR and XPS. The retanning agents were characterized by FTIR curve-fitting and circular dichroism spectroscopy. The results showed that the conformation of the secondary structure of the polypeptide became ordered and stable after coordinating with the metal ions. The particle size and weight average molecular weight of the retanning agents were ~1700 nm and ~2100, respectively, measured by nanoparticle size analyzer and gel permeation chromatography (GPC). The retanning agents were applied to retanning of chrome tanned leather and glutaraldehyde tanned leather. The abundant free amino from retanning agents can consume the free formaldehyde. Meanwhile, retanning agents can effectively improve the multiple binding sites, resulting in favorable thickening rate (>110 %) and excellent dye and fatliquor absorption rate with ~99.91 % and ~93.18 %. Thus, this strategy can provide a viable choice for solid leather waste and sustainable development of the leather industry.

Arbuscular mycorrhizal fungi promote arsenic accumulation in Pteris vittata L. through arsenic solubilization in rhizosphere soil and arsenic uptake by hyphae.

The introduction of arbuscular mycorrhizal fungi (AMF) is considered an effective strategy for improving the arsenic phytoremediation efficiency of Pteris vittata L. (P. vittata). However, how hyphae take up arsenic and translocate it to the root cells of P. vittata in the symbiotic mycorrhizal structure is currently unclear. In this study, the role of hyphae in arsenic enrichment in P. vittata and the mechanism of arsenic species transformation in the rhizosphere were studied via a compartmented cultivation setup. After Claroidoglomus etunicatum (C. etunicatum) colonization, the arsenic content of P. vittata increased by 234%. Hyphae contributed 32% to the accumulation of arsenic in symbionts. C. etunicatum promoted the conversion of iron and aluminum oxides to crystalline states in rhizosphere soil, promoted the desorption of arsenic bound to iron and aluminum oxides, and increased the content of available arsenic in rhizosphere soil by 116%. The transfer of arsenic from arbuscular structures to root cells was confirmed by transmission electron microscopy (TEM)/scanning electron microscopy- energy dispersive X-ray spectroscopy (SEMEDS) analysis. This study demonstrated that C. etunicatum inoculation enhances the phytoremediation efficiency of P. vittata in arsenic-contaminated soils through hyphal uptake, plant growth promotion, and alteration of the rhizosphere environment.

The role of plants in ironstone evolution: iron and aluminium cycling in the rhizosphere.

The Carajás plateaus in Brazil host endemic epilithic vegetation ("campo rupestre") on top of ironstone duricrusts, known as canga. This capping rock is primarily composed of iron(III) oxide minerals and forms a physically resistant horizon. Field observations reveal an intimate interaction between canga's surface and two native sedges (Rhynchospora barbata and Bulbostylis cangae). These observations suggest that certain plants contribute to the biogeochemical cycling of iron. Iron dissolution features at the root-rock interface were characterised using synchrotron-based techniques, Raman spectroscopy and scanning electron microscopy. These microscale characterisations indicate that iron is preferentially leached in the rhizosphere, enriching the comparatively insoluble aluminium around root channels. Oxalic acid and other exudates were detected in active root channels, signifying ligand-controlled iron oxide dissolution, likely driven by the plants' requirements for goethite-associated nutrients such as phosphorus. The excess iron not uptaken by the plant can reprecipitate in and around roots, line root channels and cement detrital fragments in the soil crust at the base of the plants. The reprecipitation of iron is significant as it provides a continuously forming cement, which makes canga horizons a 'self-healing' cover and contributes to them being the world's most stable continuously exposed land surfaces. Aluminium hydroxide precipitates ("gibbsite cutans") were also detected, coating some of the root cavities, often in alternating layers with goethite. This alternating pattern may correspond with oscillating oxygen concentrations in the rhizosphere. Microbial lineages known to contain iron-reducing bacteria were identified in the sedge rhizospheric microbiome and likely contribute to the reductive dissolution of iron(III) oxides within canga. Drying or percolation of oxygenated water to these anaerobic niches have led to iron mineralisation of biofilms, detected in many root channels. This study sheds light on plants' direct and indirect involvement in canga evolution, with possible implications for revegetation and surface restoration of iron mine sites.