Non-asbestiform elongate mineral particles and mesothelioma risk: Human and experimental evidence

The presentations in this session of the Monticello II conference were aimed at summarizing what is known about asbestiform and non-asbestiform elongate mineral particles (EMPs) and mesothelioma risks based on evidence from experimental and epidemiology studies. Dr. Case discussed case reports of mesothelioma over the last several decades. Dr. Taioli indicated that the epidemiology evidence concerning non-asbestiform EMPs is weak or lacking, and that progress would be limited unless mesothelioma registries are established. One exception discussed is that of taconite miners, who are exposed to grunerite. Drs. Mandel and Odo noted that studies of taconite miners in Minnesota have revealed an excess rate of mesothelioma, but the role of non-asbestiform EMPs in this excess incidence of mesothelioma is unclear. Dr. Becich discussed the National Mesothelioma Virtual Bank (NMVB), a virtual mesothelioma patient registry that includes mesothelioma patients' lifetime work histories, exposure histories, biospecimens, proteogenomic information, and imaging data that can be used in epidemiology research on mesothelioma. Dr. Bernstein indicated that there is a strong consensus that long, highly durable respirable asbestiform EMPs have the potential to cause mesothelioma, but there is continued debate concerning the biodurability required, and the dimensions (both length and diameter), the shape, and the dose associated with mesothelioma risk. Finally, Dr. Nel discussed how experimental studies of High Aspect Ratio Engineered Nanomaterials have clarified dimensional and durability features that impact disease risk, the impact of inflammation and oxidative stress on the epigenetic regulation of tumor suppressor genes, and the generation of immune suppressive effects in the mesothelioma tumor microenvironment. The session ended with a discussion of future research needs.

Determination of Active Ingredients, Mineral Composition and Antioxidant Properties of Hydroalcoholic Macerates of Vinca minor L. Plant from the Dobrogea Area

In recent decades, new alternative therapies using drugs containing active ingredients of natural origin have been a hot topic for medical research. Based on the confirmed therapeutic potential of the Vinca minor plant, considered in the specialized literature to be of pharmaceutical interest, the purpose of this study is to determine the chemical and mineral composition of the Vinca minor plant grown in the Dobrogea area, with a view to its use in the formulation of dermal preparations. For this purpose, plant materials were collected from the mentioned area and hydroalcoholic macerates of different concentrations were obtained: 40%, 70% and 96% from leaves (F40, F70, F96) and stems (T40, T70, T96) of Vinca minor plant to determine the optimal extraction solvent. The hydroalcoholic macerates were analyzed via the HPLC method for the identification and quantification of the main bioactive compounds, and two methods were used to evaluate their antioxidant properties: the DPPH radical scavenging test and the photochemiluminescence method. HPLC analysis showed the presence of four indole alkaloids: vincamine, 1,2-dehydroaspidospermidine, vincaminoreine and eburnamonine. Vincamine was the alkaloid found in the highest concentration in Vinca leaves (2.459 ± 0.035 mg/100 g d.w.). The antioxidant activity of Vinca minor hydroalcoholic macerates showed values between 737.626-1123.500 mg GAE/100 g d.w (DPPH test) and 77.439-187.817 mg TE/100 g d.w (photochemiluminescence method). The concentrations of toxic metals Cd, Cu, Ni, Pb in dried leaves and stems of Vinca minor, determined by AAS, were below detection limits.

Proximate analysis and fatty acid, mineral and soluble carbohydrate profiles of some brown macroalgae collected from Türkiye coasts

In this study, the fatty acid, carbohydrate, and mineral profiles and proximate composition of Halopteris scoparia, Padina pavonica, Zanardinia typus, Cladostephus spongiosum, Sargassum vulgare, and Sargassum acinarium brown macroalgae collected from Türkiye seas were determined. According to the results, the ash and total carbohydrate contents of all macroalgae ranged from 20.79 to 53.49% in dry weight (dw) and from 15.32 to 55.13% dw, respectively. Their protein, lipid and crude fiber contents changed between 4.22 and 9.89% dw, 0.25 and 0.90% dw, and 12.28 and 16.01% dw, respectively. Palmitic acid (29.36-48.55% dw) and oleic acid (8.92-20.92% dw) were at the highest levels in all brown macroalgae. In addition, they included prominent levels of saturated fatty acids (51.87-69.56% dw of total fatty acid content). Magnesium (6.97-18.78 mg/kg dw), potassium (1.34-3.78 mg/kg dw), iron (1.27-8.24 mg/kg dw), and manganese (63.10-252.23 μg/kg dw) were found to be the major minerals. The main soluble carbohydrates of macroalgae were found to be mannitol (1149.99-8676.31 mg/kg dw), glucose (368.78-1305.59 mg/kg dw), myo-inositol (225.96-956.78 mg/kg dw), fructose (137.05-689.21 mg/kg dw), and sucrose (189.55-328.06 mg/kg dw). This study revealed that brown macroalgae are particularly rich in potassium, magnesium, iron, manganese, and zinc and they may have potential for use in the food industry.

Linking transport pathways and phosphorus distribution in a loamy soil: a case study from a North-Eastern German Stagnosol

Heterogeneous flow pathways through the soil determine the transport of dissolved and particle-bound nutritional elements like phosphorus (P) to ground and surface waters. This study was designed to understand the spatial patterns of P in agriculturally used soils and the mechanisms causing P accumulation and depletion at the centimetre scale. We conducted dye tracer experiments using Brilliant Blue on a loamy Stagnosol in North-Eastern-Germany. The plant-available P was analysed using double lactate extraction (DL-P). The plant-available P content of the topsoil was significantly higher than that of the subsoil in all three replicates (p < 0.001). The topsoil's stained areas showed significantly higher P contents than unstained areas (p < 0.05), while the opposite was found for the subsoil. The P content varied enormously across all observed soil profiles (4 to 112 mg P kg-1 soil) and different categories of flow patterns (matrix flow, flow fingers, macropore flow, and no visible transport pathways). The P contents of these transport pathways differed significantly and followed the order: Pmatrix flow > Pfinger flow > Pno visible transport pathways > Pmacropore flow. We conclude that P tends to accumulate along flow pathways in the topsoil in the observed fertilized and tilled mineral soil. In contrast, in the subsoil at a generally lower P level, P is depleted from the prominent macroporous flow domains.

Assessment of land use and monsoon impact on high nitrate groundwater and health risk in the hard rock aquifer, South India

Groundwater sustainability in hard rock aquifers is compromised largely due to nitrate contamination from anthropogenic sources resulting in diminishing potable resources and attendant health issues. A purpose-driven study through an integrated approach was undertaken in the area of interest (hard rock aquifer) to assess the variations in nitrate concentration and resultant health impacts in response to variations in monsoon and land use patterns. Groundwater samples (n = 284) were collected for a period of three years (2017-2019) and analysed. From the analytical data, it is inferred that 27% and 9% of groundwater samples in the study area have high NO3- values of > 45 mg/l and > 100 mg/l, respectively. NO3- contamination zones mapping illustrates that NO3-contaminated area (> 45 mg/l) varied seasonally 1164 km2 (2017), 1086 km2 (2018) and 1640 km2 (2019)) and high-risk area (NO3- > 100 mg/l) has reduced drastically during 2018 due to dilution by monsoon (277 km2 (2017), 41 km2 (2018), 634 km2 (2019)). The lowest NO3- and Cl-concentrations are recorded during 2018 which coincides with high rainfall (2061 mm). NO3- concentrations in response to land use pattern indicate that the hot spots (NO3- > 45 mg/l and > 100 mg/l) are observed in groundwater samples of residential areas which are vulnerable to contamination from domestic wastewater, septic tanks and other pollutants. Further, wastewater infiltration facilitated the dissolution of certain minerals in the unsaturated zone which enhanced the accumulation of NO3- and other ions in this aquifer. Mineral weathering, denitrification and evaporation processes also affected the groundwater chemistry. The health risk model (HQoral) indicates that groundwater in 1261 km2 (2017), 1232 km2 (2018) and 1669 km2 (2019) is unsuitable for drinking (HQ > 1) and causes adverse health risks to the local inhabitants. The study has identified areas from the central and southeastern regions significantly affected by nitrate pollution underpinning the necessity of using treated groundwater for drinking purposes.

Traces of Ancient Life in Oceanic Basalt Preserved as Iron-Mineralized Ultrastructures: Implications for Detecting Extraterrestrial Biosignatures

Benefiting from their adaptability to extreme environments, subsurface microorganisms have been discovered in sedimentary and igneous rock environments on Earth and have been advocated as candidates in the search for extraterrestrial life. In this article, we study iron-mineralized microstructures in calcite-filled veins within basaltic pillows of the late Ladinian Fernazza group (Middle Triassic, 239 Ma) in Italy. These microstructures represent diverse morphologies, including filaments, globules, nodules, and micro-digitate stromatolites, which are similar to extant iron-oxidizing bacterial communities. In situ analyses including Raman spectroscopy have been used to investigate the morphological, elemental, mineralogical, and bond-vibrational modes of the microstructures. According to the Raman spectral parameters, iron minerals preserve heterogeneous ultrastructures and crystallinities, coinciding with the morphologies and precursor microbial activities. The degree of crystallinity usually represents a microscale gradient decreasing toward previously existing microbial cells, revealing a decline of mineralization due to microbial activities. This study provides an analog of possible rock-dwelling subsurface life on Mars or icy moons and advocates Raman spectroscopy as an efficient tool for in situ analyses. We put forward the concept that ultrastructural characteristics of minerals described by Raman spectral parameters corresponding to microscale morphologies could be employed as carbon-lean biosignatures in future space missions.

Assessment of seasonal changes in groundwater quality of waste rock dump in temperate continental climate, northern Japan

Understanding seasonal groundwater quality changes in temperate continental climate waste rock dumps (WRDs) is necessary for sustainable environmental risk prevention and legacy mine contamination management. Therefore, we conducted a field investigation of a WRD to determine the mechanisms controlling its groundwater quality dynamics. The research aimed to understand the impact of seasonal changes on heavy metals released from the WRD. Three monitoring wells were installed in the WRD to investigate the pH, electrical conductivity (EC), and groundwater level (GL). The mineral composition of the waste rock was determined. Groundwater and river water samples from the monitoring wells and rivers surrounding the WRD were collected for chemical analysis. The sphalerite and galena concentrated in the WRD were assumed to be the main sources of Zn, Pb, and Cd contamination. Summer rainfall was the dominant recharge source of river water, which rapidly infiltrated to the WRD, altering the pH, EC, and GL of the groundwater. The pH, EC, and GL were stable in winter because snowpack covering the surface soil prevented groundwater recharge to the WRD. However, snow melting affected the pH, EC, and GL in the WRD. The sources of groundwater recharge (rainfall, river water, and snowmelt) altered the behaviour of the heavy metals in the WRD through two main mechanisms: the dissolution of sulphide minerals and efflorescent salts upon contact with the recharge water, and the dilution effect of the recharge water, which mixes with the groundwater in the WRD, reducing the heavy metal concentration. Sulphide mineral and efflorescent salt dissolution were significant in the deepest monitoring well and rainfall was the dominant recharge source which increased sulphide mineral and efflorescent salt dissolution in the WRD.

Safe usage of Cd-polluted paddy fields using alkaline Si-rich compound amendment: Effect and mechanism

A low-cost practical technology is urgently needed to minimize cadmium (Cd) pollution in rice in many parts of the world. In the present study, we elucidated the effects and mechanisms of four alkaline compound materials via field experiments in southern China. The results indicated that these two alkaline Si-rich compound materials (AF-SC, alkaline fertilizer compounded with Si-Ca mineral powder; AF-SS, AF compounded with Si-Se mineral powder) could achieve multi-objective gains by simultaneously reducing grain Cd, increasing yield and improving soil quality at a lower cost. The grain Cd content was decreased by an average of about 75% in two field sites, which even ensured safe grain production in areas with medium Cd pollution. The rice yield was increased by a range of 6.7%-21.0% for different varieties and sites. Moreover, the materials abated soil acidification with the increase of 0.36-0.62 pH units, increased the contents of available P and available Si, subsequently reducing available Cd content in soils. Structural equation model and regression analysis showed that the alkaline environment provided by the alkaline components in compound materials effectively inhibited the formation of Fe/Mn plaques on the root surface, reducing the uptake of Cd from the environment. In addition, the decrease in grain Cd was also attributed to the inhibition of Cd translocation from root to stem, mainly caused by the increase of available Si. These findings reveal that the base application of such alkaline Si-rich compound materials is a viable solution for the remediation of Cd-polluted paddy fields in south China.

The Effect of Flake Production and In Vitro Digestion on Releasing Minerals and Trace Elements from Wheat Flakes: The Extended Study of Dietary Intakes for Individual Life Stage Groups

This thorough study analyses the amounts of 43 minerals and trace elements in non-traditional wheat grains, flakes, and undigested flake portions using ICP-MS and establishes declines in their respective contents after the flake production. It also identifies appropriate dietary intakes, in vitro digestibility values, retention factors, and metal pollution indexes. The element contents in wheat flakes are lower than in wheat grains after the hydrothermal treatment process, and their declines are: Na (48-72%), Ce (47-72%), Sr (43-55%), Tl (33-43%), Ti (32-41%), U (31-44%), Ho (29-69%), Cr (26-64%), Zr (26-58%), Ag (25-52%), and Ca (25-46%). The flakes significantly contributed to the recommended dietary intake or adequate intake of particular elements for men of all categories as follows: Mn (143%) > Mo > Cu > Mg ≥ Cr > Fe (16%); for women: Mn (up to 183%) > Mo > Cu > Cr ≥ Mg > Fe (7-16%); for pregnant women aged 19-30: Mn (165%) > Mo > Cu > Mg > Cr (25%); and finally, for lactating women: Mn (127%) > Mo > Cu > Mg > Cr (17%). The contributions to the provisional tolerable weekly or monthly intakes of all toxic elements were established as being within the official limits. The daily intakes for non-essential elements were also calculated. The retention factors were calculated to assess the element concentrations in the undigested part using the digestibility values (87.4-90.5%). The highest retention factors were obtained for V (63-92%), Y (57-96%), Ce (43-76%), Pb (34-58%), Tl (32-70%), Ta (31-66%), and Ge (30-49%). K, Mg, P, Zn, Ba, Bi, Ga, Sb, Cu, Ni, and As appear to be released easily from flake matrices during digestion. The metal pollution index has been confirmed as being lower for non-traditional wheat flakes when compared with grains. Importantly, 15-25% of the metal pollution index assessed for native flakes remains in the undigested flake portion after in vitro digestion.

Assessment of metal pollution and human health risks in road dust from mineral rich zone of East Singhbhum, India

A detailed study of heavy metals in the road dust of a mineral rich zone of Jharkhand state, India is reported herein. Metal concentrations in the road dust exceeded the corresponding values in the average shale as well as world average of soil. Metal pollution due to the road dust and the possible health impact arising there from was appraised through a number of indices such as Geo-accumulation Index (I_geo), Pollution Load Index, Enrichment Factor (EF), Contamination Factor and US EPA Hazard Index and Cancer Risk. Cu contamination was highest as per EF and Igeo, followed by Pb and Zn. Aggravated heavy metal loading in the road dust was conspicuous in the proximity of copper mines and processing units. Both geogenic and anthropogenic sources were responsible for heavy metals in road dust according to principal component analysis. Hazard Quotient, Hazard Index and Cancer Risk were calculated to ascertain non-carcinogenic and carcinogenic health risks in adults and children. Local inhabitants, particularly children, were under appreciable cancer and non-cancer risk. Oral ingestion was the major pathway for risk to the local commuters followed by dermal pathway. Present study underscored the importance of regular heavy metal monitoring of road dust in this zone and administer proactive road dust management practices to reduce metal pollution.

Classification of groundwater using multivariate statistical methods: a case study from a part of Haryana, northwestern India

This article aimed to estimate the local underground water associations, which will, in turn, be applied to discuss the location of each underground water cluster in the flow system. Additionally, this investigation intended to evaluate underground water's aptness from aquifers of the study area for domestic agricultural activities and the prime sources of alteration in the water chemistry. Geographically, the region does not have the privilege of the river (except the Yamuna in the eastern part) running through it and thus, has to rely heavily on groundwater. Therefore, it is necessary to study the groundwater characteristics in this region. This investigation manifested two sub-surface water associations (groups) showing two prime underground water types in the study area: the calcium-magnesium-bicarbonate water-types, groups (clusters) 1 member; and the sodium-bicarbonate-chloride water-types consisting of Group 2 members during post-monsoon and pre-monsoon periods. Group 1 is typical of underground water in recharge regions of the underground water flow system. It is the cleanest underground water type in part except for a few groundwater samples. The highest mean salinity was vested in group 2, the signature of underground waters in discharge regions of the underground water flow system. This investigation observes that three principal elements controlled the hydro-chemistry of underground water in the study area: chemical fertilizers from farms, carbonate mineral weathering, calcite, fluorite, silicate minerals, and exchange of cations in the region. All the underground water groups had high sodium (Na) concentrations and will cause the Na-hazard when applied for agricultural activities. Most samples of groups 1 and 2 were within the class II and I area of Doneen's plot during both periods and were therefore acceptable for agricultural activities in the investigation region.

Mineral Content Variation in Leaves, Stalks, and Seeds of Celery (Apium graveolens L.) Genotypes

Celery is an important nutritionally rich crop in the family Apiaceae. It is cultivated worldwide for food as well as for use in pharmaceutics. It is an excellent source of minerals, vitamins, and phytochemicals. Identification of superior genotypes with improved nutritional content is the requirement to develop cultivars for commercial cultivation. For mineral analysis of celery, an experiment was carried out taking 20 diverse genotypes. These genotypes were analysed for macro- and micronutrients which include nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), iron (Fe), zinc (Zn), manganese (Mn), copper (Cu), and sodium (Na). The study revealed high content of K (20.3-26.1 mg/g dry weight (DW)) and Zn (0.09-0.14 mg/g DW) in leaves while the stalks were rich in Ca (41.5-51.3 mg/g DW) and Na (5.2-8.0 mg/g DW). High contents of P (5.2-6.8 mg/g DW), Fe (0.41-0.56 mg/g DW), Cu (0.015-0.026 mg/g DW), and Mn (0.020-0.029 mg/g DW) were observed in seeds. Based on the mineral content, three genotypes, viz., PAU2, PAU4, and PAU7, were found to be superior in terms of mineral composition in leaves, stalks, and seeds. Cluster analysis divided the genotypes into two major groups. These genotypes can be used in crosses as they showed great potential for use in biofortification. This study opens newer avenues for future research, encouraging researchers to enhance the product quality and production efficiency of the leaves, stalks, and seeds valuable for human consumption.

Hydrogeochemical factors controlling the occurrence of chronic kidney disease of unknown etiology (CKDu)

Chronic kidney disease of unknown etiology (CKDu) has posed a serious threat to human health around the world. The link between the prevalence of CKDu and groundwater geochemistry is not well understood. To identify the potential geogenic risk factors, we collected 52 groundwater samples related to CKDu (CKDu groundwater) and 18 groundwater samples related to non-CKDu (non-CKDu groundwater) from the typical CKDu prevailing areas in Sri Lanka. Results demonstrated that CKDu groundwater had significantly higher Si (average 30.1 mg/L, p < 0.05) and F^- (average 0.80 mg/L, p < 0.05) concentrations than those of non-CKDu groundwater (average 21.0 and 0.45 mg/L, respectively), indicating that Si and F^- were the potential risk factors causing CKDu. The principal hydrogeochemical process controlling local groundwater chemistry was chemical weathering of silicates in Precambrian metamorphic rocks. Groundwater samples were mostly undersaturated with respect to amorphous silica and clay minerals such as talc and sepiolite, which was conducive to silicate weathering and elevated Si concentrations in groundwater. Decreased Ca²⁺ being facilitated by calcite precipitation and cation exchange between Ca²⁺ and Na⁺ favored fluorite dissolution and thus led to high groundwater F^- concentrations. Competitive adsorption between [Formula: see text] and F^- also enhanced the release of F^- from solid surfaces. This study highlights the CKDu potential risk factors regarding groundwater geochemistry and their enrichment factors, which helps in preventing the prevalence of CKDu.

Radiogeochemistry, mineralogy, lithology, radiogenic heat production, and health implication using airborne radiometric data of Ilesha and its surroundings

The current study analyzed and interpreted airborne radiometric data from Ilesha's basement complex rock and its surroundings. At the surface, the concentrations of the most frequent primordial radionuclides notably K, elemental concentration of uranium eU, and elemental concentration of thorium eTh were measured. The weighted mean elemental and activity concentrations were 0.85%, 2.75 ppm, 10.22 ppm, and 267.54 Bq kg^-1, 34.41 Bq kg^-1, 41.51 Bq kg^-1 for ⁴⁰ K, ²³⁸U, and ²³²Th, respectively. The low concentration of ⁴⁰ K was certainly due to the effects of weathering, kaolinization of granites, and pedogenesis activities. The abundance of uranium was ascribed to the availability of uranium minerals such as allanite, apatite, and sphene with accessories minerals, while that of thorium was due to minerals such as cheralite, thorite, uranothorite, thorianite, and uranothorianite with accessories minerals. The RPHR weighted mean 1.48 µWm^-3 compared to the earth's crust mean between 0.8 and1.2 µWm^-3 was higher due to significant presence of gneiss rocks in all the studied profiles. Radiological hazard, in particular, dose rates, external hazard index, internal hazard index, radium equivalent, annual gonadal dose, effective dose dispensed to various organs of the body were computed to determine the deleterious effects of rocks in the area. The weighted means of annual gonadal dose of 363.98 µSv y^-1 and outdoor 0.91 × 10^×3 and indoor 1.65 × 10^-3 excessive life cancer risks were more than the global average 300 µSv y^-1, 0.29 × 10^-3 and 1.16 × 10^-3. As a result, proper surveillance is required in the area in order to prevent epidemics occurrence in future.

Plant-minerals-water interactions: An investigation on Juncus acutus exposed to different Zn sources

Juncus acutus has been proposed as a suitable species for the design of phytoremediation plans. This research aimed to investigate the role played by rhizosphere minerals and water composition on Zn transformations and dynamics in the rhizosphere-plant system of J. acutus exposed to different Zn sources. Rhizobox experiments were conducted using three different growing substrates (Zn from 137 to 20,400 mg/kg), and two irrigation lines (Zn 0.05 and 180 mg/l). The plant growth was affected by the substrate type, whereas the Zn content in the water did not significantly influence the plant height for a specific substrate. J. acutus accumulated Zn mainly in roots (up to 10,000 mg/kg dw); the metal supply by the water led to variable increases in the total Zn concentration in the vegetal organs, and different Zn distributions both controlled by the rhizosphere mineral composition. Different Zn complexation mechanisms were observed, mainly driven by cysteine and citrate compounds, whose amount increased linearly with Zn content in water, but differently for each of the investigated systems. Our study contributes to gain a more complete picture of the Zn pathway in the rhizosphere-plant system of J. acutus. We demonstrated that this vegetal species is not only capable of developing site-specific tolerance mechanisms, but it is also capable to differently modulate Zn transformation when Zn is additionally supplied by watering. These findings are necessary for predicting the fate of Zn during phytoremediation of sites characterized by specific mineralogical properties and subject to water chemical variations.

Evaluation of metal exposure through the composition of essential and toxic micro-minerals in freshwater turtles (Phrynops geoffroanus) from a Brazilian river

This study aimed to evaluate metal exposure through the concentration of essential and toxic micro-minerals in biological samples of Phrynops geoffroanus from an anthropized river. The work was carried out in four areas with different flow characteristics and uses of the river, where individuals of both sexes were captured during the dry and rainy seasons. The elements Al, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, and Zn were quantified in samples of serum (168), muscle (62), liver (61), and kidney (61) by inductively coupled plasma optical emission spectrometry. The concentration of the elements varied according to the sample type, being higher in the liver and the kidney. In the serum, many elements were below the limit of quantification, but it was possible to determine Al, Cu, Fe, Mn, Pb, and Zn. The liver showed high levels of Cu, Fe, Pb, and Zn, and muscle for Fe, Ni, Pb, and Zn, with most of the elements accumulated in the kidney (Al, Cd, Co, Cr, Mn, Mo, and Ni) relative to other tissues. There was no significant difference between the sexes in the accumulation of elements. Between seasons, Cu was higher in serum and Mn in muscle and liver in the dry period, while in the kidney, almost all the elements were higher in the rainy period. The concentrations of the elements in the samples indicated a high degree of environmental contamination, representing risk in the use of the river and consumption of food from local fisheries.

Thermodynamic characterization of LF, H, and mineral soil layers from oak forest ecosystems: Exploring the role of proximate analysis

Studying the thermodynamic properties of soil organic matter is a developing field that involves the measurement of the energy stored by the soil. Quantifying soil energy content is still challenging despite different methodological approaches are available to calculate that value. One of the options is the proximate analysis following the guidelines for the energetic characterization of biomass. However, proximate analyses are still unexplored for soils. In this paper, we investigate the potential of this analysis to contribute to study soil from a thermodynamic perspective. With that goal, 31 soil samples collected in mature oak forests following a depth transect were used for elemental, thermal and proximate analysis. Proximate analyses and energetic characterization were performed by simultaneous thermogravimetry and differential scanning calorimetry. These methods allowed fragmentation of the soil organic matter in water content, volatile matter, fixed carbon, and ash, as well as the quantification of the soil organic matter and energy content. Pearson's correlation showed significant relations among the proximate, the elemental components of soils and the energy. The equations relating all of these variables were calculated for soils from oak forests by partial least squares analysis. Equations representing the relationship between energy and the proximate fractions provide an additional alternative to calculate the heat of combustion of the soil organic matter. This value is the essential step for the thermodynamic characterization of soils.

Dissolved thiolated arsenic formed by weathering of mine wastes

Aqueous thiolated arsenic (As) species play an important role in the biogeochemical cycling of As in wetlands and hydrothermal systems. Although mine wastes such as tailings ponds and waste rock piles may harbor similarly sub-oxic and neutral to alkaline conditions that favor the formation and mobility of thio-As species, quantitative data on their existence in these systems is lacking. We conducted laboratory column experiments under contrasting redox conditions with waste rock from the Antamina mine, Peru, and processed tailings from Montague, Nova Scotia, Canada. Dissolved As concentrations between 1 and 7000 μg/L were recorded in drainages across these mine waste types, with up to 13 μg/L As present in thiolated form, predominantly monothioarsenate. Higher percentages of thio-As species (up to 5%) were observed in drainages from enargite-rich materials compared to arsenopyrite-bearing materials (<0.5%). The lower abundance of dissolved thio-As in the arsenopyrite-rich mine waste samples is attributed to their partially oxidized nature and reduced mineral reactivity under the experimental circumneutral drainage pH, the difference in S [-II/0]-to-As molar ratios compared to the enargite-rich mine waste samples, as well as the oxidation of di- and tri-thiolated As species by dissolved Fe. Overall, our results demonstrate that aqueous thiolated As species may occur in mine wastes with different As-bearing minerals and could play an important role in governing the mobility and fate of As in these systems.

An improved balanced replicated sampling design for preliminary screening of the tailings ponds aiming at zero-waste valorization. A Romanian case study

The scope of this study consists of setting up of an integrated cost-effective sampling & laboratory analyses procedure which delineates sampling, sub-sampling and analytical uncertainties in case of fine-grained extractive waste deposits. This procedure is designed to support the decision makers towards fine-grained waste deposits upcycling and land reclamation. This procedure consists of a balanced replicated sampling design (BRSD) coupled with a three split levels ANOVA data processing. The paper provides the readership with the mathematical backgrounds of the three split level ANOVA analysis (3L-ANOVA) and an Excel algorithm for its implementation. Also, the paper presents an example of implementation of the developed methods in the case of a Romanian iron ore tailings (IOT) old pond. The findings of the paper consist of: a) argues, based on OM, SEM-EDS, XRFS and XRD observations, that classical TOS is ineffective for fine-grained waste deposits; b) BRSD in conjunction with 3L-ANOVA analysis is the only approach fit for reliable characterization of the fine-grained stockpiles; c) sampling uncertainty is the critical factor of the uncertainty budget of the analyte concentration; d) Lilliefors approach is adequate for the hypothesis testing where or not the measurand is normal distributed; e) The outcomes of the BRDSD&3L-ANOVA investigations carried on Teliuc tailings, estimated at circa 5.5* 106 m3, consist mainly of mineral quantification at lot level i.e. quartz ∼54% (±7%), hematite ∼15% (±3%), calcite ∼11% (±3%), MgO 3% (±1%), Al2O3 9% (±2%). The concentrations of some CRMs like Ti, V, Ba, Y, W were found at ACE limits and their associated relative expanded uncertainties overpass 50%. Thus, the expanded uncertainties clearly depict the reliability of acquired data for the decision makers regarding waste valorization. f) The IOT into Teliuc can be upcycled as minerals for cement and ceramic industries as well as for geopolymer manufacture. Also, IOT can be downcycles as filler in road construction and mine closure. Finally, the Teliuc yard can be rehabilitated with zero-waste left behind. The data exactness provided by this procedure can be increased to any desirable level through increasing the number of collected items, but the cost of sampling and analyses increases proportionally. In such circumstances, the posted approach can be tailored at the stakeholder request as to safely underpin the decision to turn finegrained by-products into valuable secondary resources, facilitating a greater circularity of the mining industry.

Method development to characterise elephant tail hairs by LA-ICP-MS to reflect changes in elemental chemistry

This paper evaluated analytical methods used to generate time-series data from elephant tail hairs, which can be used to reflect changing exposure to environmental geochemistry. Elephant tail hairs were analysed by three methods sequentially, each providing data to inform subsequent analysis. Scanning Electron Microscopy (SEM) and X-ray Microanalysis visually showed the structure of the hair, specific structures such as tubules, and the mineral crusting around the edge of the hair, informing targeting of subsequent analysis by Laser Ablation-Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS). LA-ICP-MS generated time-series data which informed sectioning of the tail hairs for subsequent quantitative analysis for potentially toxic elements and micronutrients using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) of dissolved tail hairs. This novel approach to characterise the tail hair enabled time-series analysis to reflect changes in environmental exposure which may result from seasonal or geochemical spatial variation and could inform elephant movement patterns. The seasonal change between wet and dry seasons was reflected down the length of the hair. Correlations were seen between LA-ICP-MS data and ICP-MS data in several elements including Mg, P, Ca, Fe, Na, Mn and U. This study provided time-series data for the analysis of elephant tail hairs by evaluating analytical challenges to obtaining quantitative data, such as improving protocols to ensure removal of extraneous material, determining where to section the tail hairs to best reflect environmental changes/exposure and ensuring representative analyses. A protocol was established to determine mineral status across a 12-18 month time period utilizing single elephant tail hairs.

Nutritional aspects of non-conventional edible plants from Brazil: Caruru (Amaranthus spinosus L) and trapoeraba (Commelina benghalensis)

Caruru (Amaranthus spinosus L) and trapoeraba (Commelina benghalensis) are NCEPs introduced into Brazil and are widely used by certain communities. Given the lack of information on carotenoids, vitamins, and minerals present in A. spinosus and C. benghalensis grown in Brazil, this study aimed to determine the proximate composition and the micronutrient profile of these two NCEPs obtained from family farming in the Middle Doce River (Médio Rio Doce) region in the state of Minas Gerais, Brazil. The proximate composition was evaluated using AOAC methods, vitamin E by HPLC with fluorescence detection, vitamin C and carotenoids by HPLC-DAD, and minerals by atomic emission spectrometry with inductively coupled plasma. In summary, the leaves of A. spinosus exhibited a high content of dietary fiber (10.20 g.100 g^-1), potassium (708.8 mg·100 g^-1), iron (4.0 mg·100 g^-1) and β-carotene (6.94 mg·100 g^-1), while the leaves of C. benghalensis were sources of potassium (1399.31 mg·100 g^-1), iron (5.7 mg·100 g^-1), calcium (163 mg·100 g^-1), zinc (1.3 mg·100 g^-1), ascorbic acid (23.61 mg·100 g^-1), and β-carotene (31.33 mg·100 g^-1). It was therefore concluded that C. benghalensis and A. spinosus, especially, presented excellent potential as important nutritional sources for human consumption, highlighting the gap existing between the available technical and scientific material, thus making them an important and necessary axis of research.

Thermal Stability of (Bio)Carbonates: A Potential Signature for Detecting Life on Mars?

The environmental conditions that prevail on the surface of Mars (i.e., high levels of radiation and oxidants) are not favorable for the long-term preservation of organic compounds on which all strategies for finding life on Mars have been based to date. Since life commonly produces minerals that are considered more resilient, the search for biominerals could constitute a promising alternative approach. Carbonates are major biominerals on Earth, and although they have not been detected in large amounts at the martian surface, recent observations show that they could constitute a significant part of the inorganic component in the martian soil. Previous studies have shown that calcite and aragonite produced by eukaryotes thermally decompose at temperatures 15°C lower than those of their abiotic counterparts. By using carbonate concretions formed by microorganisms, we find that natural and experimental carbonates produced by prokaryotes decompose at 28°C below their abiotic counterparts. The study of this sample set serves as a proof of concept for the differential thermal analysis approach to distinguish abiotic from bio-related carbonates. This difference in carbonate decomposition temperature can be used as a first physical evidence of life on Mars to be searched by in situ space exploration missions with the resolution and the technical constraints of the available onboard instruments.

Minerals, fatty acids, and antioxidant activity in sea knotgrass (Polygonum maritimum L.) seeds

The design of the current study was to determine the functional properties of P. maritimum seeds by evaluating their mineral content, fatty acid composition, and biactive compounds. Results showed that seeds contained remarkable amounts of Na, K, Ca, Mg, Cu, Zn, and Fe. The oil yield was found to be 4.58% and contained higher unsaturated fatty acids predominated by linoleic and oleic acids. The colorimetric investigation revealed high total polyphenol (33.56 mg gallic acid equivalent/g), flavonoid (46.3 mg quercetin equivalent/g), and condensed tannin (22.3 mg catechin equivalent/g) contents. Furthermore, the LC-ESI/MS analysis revealed the presence of 13 phenolics mostly predominated by (+) catechin, quercetin-3-O-galactoside, gallic acid, and quinic acid. The seeds possessed strong antioxidant potential evidenced by ABTS and DPPH radical scavenging activities, total antioxidant capacity, and reducing power. The present findings suggest that P. maritimum seeds may be used as a potential source of biologically active natural products.

Main chemical and mineralogical components of the Rio Doce sediments and the iron ore tailing from the Fundão Dam disaster, Southeastern Brazil

Since the Fundão Dam rupture in Southeastern Brazil caused an enormous amount of iron ore tailing (IOT) to be discharged into the Doce River Catchment, various works have been published on the soil, water, and biota contamination by potentially hazardous trace metals. However, the objective of this study is to investigate changes in the main chemical composition and the mineral phases, which has not been studied yet. We present an analysis of sediment samples collected in the Doce River alluvial plain, before and after the disaster, as well as the tailing deposited. Granulometry, main chemical composition by X-ray fluorescence spectrometry, mineralogy by X-ray diffractometry, quantification of mineral phases using the Rietveld method, and scanning electron microscope imaging are shown. We conclude that the Fundão Dam rupture introduced fine particles into the Doce River alluvial plain, increasing the Fe and Al content in the sediments. The high Fe, Al, and Mn contents in the finer iron ore tailing fractions represent environmental risks for soil, water, and biotic chains. The IOT mineralogical components, mainly the muscovite, kaolinite, and hematite present in the finer particles can increase the sorption and desorption capacity of harmful trace metals depending on the natural or induced redox conditions, which are not always predictable and avoidable in the environment.

Geographic information system-based groundwater quality assessment for drinking and irrigation purposes in transboundary aquifers of River Ravi, India

Access to safe and clean drinking water is a basic human right, and assessment of groundwater suitability for drinking purpose imparts significant role in providing clean and suitable water for human consumption. The main objective of this study was to assess the groundwater quality status of Gurdaspur district falling along international boundary of Indo-Pak, thus serving as transboundary aquifers, for drinking and irrigation purpose based on physicochemical analysis of 111 samples using standard numerical indices and GIS techniques. Shannon's entropy theory was employed to assess the groundwater quality for human consumption as it removes the subjectivity problem and integral ambiguities of groundwater systems. The results of entropy water quality index revealed that the drinking groundwater quality was found to be in excellent, good and medium water class except 5 samples which were in poor to extremely poor water class. Piper trilinear plot revealed that the main water types were Ca²⁺ and Mg²⁺-HCO₃^-. Mineral saturation index indicated that carbonate minerals were oversaturated and the evaporative minerals were undersaturated. The outcomes of principal component analysis indicated that the ion exchange, weathering and agricultural practices were the dominant controlling factors in the study area. Furthermore, the results of the irrigation water quality index illustrated that 3 and 65 samples were placed in 'severe restriction' and 'high restriction' class respectively indicating irrigation water as an issue for sustainable agricultural production in agrarian dominant district. The study recommends the adaptation of remedial actions particularly in the regions where drinking and irrigational groundwater quality issues are reported to ensure clean and suitable drinking water for the inhabitants.