Copper Concentrations Research Articles

Responses of 'Flordaguard' and 'MP-29' Prunus spp. rootstocks to hypoxia and high root zone temperature.

Selecting the right rootstock is crucial for successful fruit production and managing both biotic and abiotic stresses in commercial fruit orchards. To enhance the resilience of peach orchards, this study evaluated the physiological and biochemical responses of Prunus spp. rootstocks , 'Flordaguard' and 'MP-29,' under normoxia (sufficient oxygen content) or short-term hypoxia (low-oxygen content) and ambient or high temperature (40°C) in the root zone. Physiological responses measured were net photosynthesis, stomatal conductance, transpiration, intercellular CO2 concentration, water use efficiency, the leaf chlorophyll index, and the maximum potential quantum efficiency of photosystem II. The leaf concentrations of nitrogen, phosphorus, potassium, magnesium, calcium, sulfur, boron, zinc, manganese, iron, and copper were also analyzed. Reactive oxygen species (ROS) and antioxidants analyzed were superoxide dismutase (SOD) activity, peroxidase (POD) activity, catalase (CAT) activity, ascorbate peroxidase (APX) activity, glutathione peroxidase (GPX) activity, proline content, glycine betaine content (GB), lipid peroxidation (LPO), superoxide (O2 -) concentration, and hydrogen peroxide (H2O2) concentration. When subjected to root zone hypoxia or high temperature individually, 'MP-29' performed better physiologically than 'Flordaguard'. However, when root zone hypoxia and high temperature were combined, 'MP-29' performed better biochemically with enhanced antioxidant activity, osmolyte content, and nutrient absorption. Nutrient analysis of leaves revealed that 'MP-29' had higher N, P, K, Ca, and B concentrations than 'Flordaguard'. Consequently, 'MP-29' demonstrated greater tolerance to short-term exposure to the combined effects of high root zone temperature and hypoxia. This research contributes to identifying a suitable rootstock within the Prunus genus able to withstand root zone conditions that often result from severe weather events commonly experienced in Florida and other parts of the world.

تقدير المعادن الثقيلة في بعض أنواع مختلفة الكعك المجمعة من أسواق مدينة البيضاء – ليبيا

Heavy metals are chemical elements with high density and atomic weight. Despite their widespread use in various industries and applications, they pose significant risks to the environment and public health if not handled properly. This study was conducted to estimate the concentration of some different elements in different types of cakes, where cake samples were collected from different shops from Al-Bayda city, the study dealt with six types of cakes. Flame photometer was used to estimate sodium and potassium salts and spectrophotometer to estimate heavy elements. The samples were digested using the digestion method using HNO1 and HCl and heating until the brown oxides evaporate and we get half the amount. The results showed that the concentration of sodium, chromium, iron and copper is below the permissible limits and the concentration of potassium is higher than the permissible limits and the results also showed that the collected cake samples do not contain lead and a discrepancy was observed .The potassium concentration ranged from (541. 50 to 763.25), sodium concentration ranges from (1.34 to 3.52), iron concentration ranges from (1.72 to 7.16), copper concentration ranges from (44.36 to 67.62), and chromium concentration ranges from (0 to 0.25). The study could be expanded to include other types of cakes, such as filled cakes to provide a more comprehensive picture of heavy metal contamination in these products. More heavy metals, such as mercury, arsenic, and cadmium, could be analyzed to more accurately assess health risks. Keywords: Heavy metals, Cakes types, market and Al-Bayda – Libya.

Integrated environmental and social assessment of alum-contaminated water in An Giang province

ABSTRACT This study investigates alum-contaminated water in An Giang province within the Mekong Delta, emphasizing methodological approaches to assess its distribution and impacts. The research conducted from March to May 2021 involved surveys of residents, public sector employees, and provincial managers, complemented by expert interviews and extensive fieldwork. Surface water samples were collected during both rainy and dry seasons across three districts, with parameters such as turbidity, pH, and temperature measured onsite, and aluminum (Al), iron (Fe), and copper (Cu) concentrations analyzed in the laboratory using atomic absorption spectrometry. The data were further processed using QGIS software to create comprehensive maps illustrating seasonal variations in water quality. The findings revealed significant spatial and temporal variations in water quality, with pH levels fluctuating markedly between the dry and rainy seasons. Household surveys indicated a lack of awareness regarding effective water treatment methods, with most respondents relying on local authorities for solutions. The study highlights the need for community education and participation in addressing alum contamination, offering insights into the environmental and public health implications of water quality in the region. This research contributes valuable knowledge to the ongoing efforts in environmental conservation and water quality management in the Mekong Delta.

Blowin' in the Wind: Mapping the Dispersion of Metal(loid)s From Atacama Mining.

The Atacama Desert's naturally elevated metal(loid)s pose a unique challenge for assessing the environmental impact of mining, particularly for indigenous communities residing in these areas. This study investigates how copper mining influences the dispersion of these elements in the wind-transportable fraction (<75μm) of surface sediments across an 80km radius. We employed a multi-pronged approach, utilizing spatial modeling to map element distributions, exponential decay analysis to quantify concentration decline with distance, regime shift modeling to identify dispersion pattern variations, and pollution assessment to evaluate impact. Our results reveal significant mining-driven increases in surface concentrations of copper (Cu), molybdenum (Mo), and arsenic (As). Notably, within the first 20km, concentrations peaked at 1,016mgkg⁻1 for Cu, 31mgkg⁻1 for Mo, and a remarkable 165mgkg⁻1 for As. Cu and Mo displayed significant dispersion, extending up to 50km from the source. However, As exhibited the most extensive reach, traveling up to 70km downwind, highlighting the far-reaching ecological footprint of mining operations. Mineralogical analyses corroborated these findings, identifying mining-related minerals in surface sediments far beyond the immediate mining area. Although pollution indices based on the proposed Local Geochemical Background reveal significant contamination across the study area, establishing accurate pre-industrial baseline values is essential for a more reliable assessment. This study challenges the concept of "natural pollution" by demonstrating that human activities exacerbate baseline metal(loid)s levels. Expanding monitoring protocols is imperative to comprehensively assess the combined effects of multiple emission sources, including mining and natural processes, in safeguarding environmental and human health for future generations.

The antibacterial activity of the copper for Staphylococcus aureus 124 and Pseudomonas aeruginosa 18 depends on its state: metalized, chelated and ionic

The hypothesis that the antibacterial effect of copper depends on its state was tested. It was studied the antibacterial effect of copper applied to the fabric, copper in chelated and free (ionic) forms on the growth intensity of Staphylococcus aureus 124 and Pseudomonas aeruginosa 18 in the in vitro system after a single or “primary” contact. Classical microbiology methods were used. Copper was applied to the fabric by magnetron and arc planar discharge systems, and the culture of microalgae Dunaliella viridis, resistant to the action of high concentrations of copper, was used to obtain copper in chelated form. It was shown that a thin layer of copper (3 μm) applied to the fabric showed pronounced antibacterial activity against Staphylococcus (85 % compared to the antibiotic meropenem) and less pronounced activity against Pseudomonas, which is resistant to meropenem. Copper in ionic form inhibited the growth of Staphylococcus aureus 124 as well as the antibiotic, and also effectively inhibited the growth of Pseudomonas aeruginosa 18 i.e., copper ions did not have species specificity like the antibiotic. Components of Dunaliella viridis microalgae cells had weakly expressed antibacterial effect to these types of bacteria, and supplementary addition of copper sulfate to the biomass of microalgae led to an increase of their antibacterial activity and this is more pronounced for microalgae culture in which the ratio « chelated/ionic » forms of copper is shifted to the ionic form. It was shown that the antibacterial activity of microalgae biomass after the first introduction into the tested bacterial cultures depends on the amount of free or “weakly bound” with cell components copper ions. It is suggested that the antibacterial effect of fabric with a thin layer of copper may be determined by two mechanisms: the action of copper ions and mechano-bactericidal effects, while chelated forms of copper may have a prolonged effect on bacterial cultures.

The Tao of Copper Metabolism: From Physiology to Pathology.

As a transitional metal, copper plays a crucial role in maintaining the normal physiological activities of mammals. The intracellular copper concentration is meticulously regulated to maintain extremely low levels through homeostatic regulation. Excessive accumulation of free copper in cells can have deleterious effects, as observed in conditions such as Wilson's disease. Moreover, data accumulated over the past few decades have revealed a crucial role of copper imbalance in tumorigenesis, progression and metastasis. Recently, cuproptosis, also known as copper-induced cell death, has been proposed as a novel form of cell death. This discovery offers new prospects for treating copperrelated diseases and provides a promising avenue for developing copper-responsive therapies, particularly in cancer treatment. We present a comprehensive overview of the Yin- Yang equilibrium in copper metabolism, particularly emphasising its pathophysiological alterations and their relevance to copper-related diseases and malignancies.

Dysfunction of ATP7B Splicing Variant Caused by Enhanced Interaction With COMMD1 in Wilson Disease

Background & AimsThe association between Wilson disease and various ATP7B mutations is well-established; however, the molecular mechanism underlying the functional consequence of these mutations, particularly the splicing mutations, remains unclear. This study focused on the ATP7B c.1543+1G>C variant, to reveal a universal pathogenic mechanism of the ATP7B mutants with altered N-terminus. MethodsThe splicing assay and RNA pull-down were performed to explore the mechanism of the aberrant splicing. The ATP7B knockout HuH-7 cell line and Atp7b-/- mice were created, and the functional consequence of the mutant ATP7B were evaluated in-vitro and in-vivo. ResultsThe c.1543+1G>C mutation resulted in the skipping of ATP7B exon 3, and the mutant ATP7B showed a loss of trans-Golgi network (TGN) localization and was degraded via the ubiquitin-proteasome pathway, facilitated by enhanced interactions with COMMD1. Elevated intercellular copper concentration and reduced survival rate were observed in HuH-7 cells expressing mutant ATP7B. Restoration of wild-type ATP7B in Atp7b-/- mice resulted in a substantial improvement in phenotype, while mice treated with mutant ATP7B did not demonstrate equivalent benefits. ConclusionsOur research investigated the pathogenicity and mechanism of ATP7B c.1543+1G>C variant, with particular focus on its enhanced interaction with COMMD1 as a potential universal mechanism contributing to the dysfunction of various ATP7B variants. These findings provide a foundation for the development of innovative therapeutic strategies that target abnormal splicing events in a range of hereditary diseases, including Wilson disease.

Analysis and Detection of Heavy Metals Content in Some Selected Packaged Fruit Juices of Kathmandu City by Flame Atomic Absorption Spectroscopy

The determination of level of heavy metals in packaged fruit juices is crucial, as extended exposure to even small quantities of these toxic element can cause severe health issues and chronic poisoning. Hence, it is essential to gather comprehensive data on the presence of heavy metals in packaged fruit juice samples. The objective of this research work is to determine heavy metals (Fe, Cu, Zn and Pb) in four different types of packaged fruit juice samples viz Apple, Mango, Orange and Lychee of four different popular brands bought from retail market of Kathmandu city by flame atomic absorption spectroscopy and compare with acceptable limit set by WHO/FAO. Wet acid digestion method was used for digestion process of packaged fruit juice samples. The concentration of Iron were ranged from 0.572-0.762mg/L in Orange juices; 0.362-0.624mg/L in Mango juices; 0.277-3.649mg/L in Apple juices; 0.279-1.770mg/L in Lychee juices respectively. Copper concentration were ranged from not detected (ND)-0.574mg/L in Orange juices; ND for all selected samples in Mango juices; ND- 0.023mg/L in Apple juices; ND-0.041mg/L in Lyclee juices. Similarly Zinc concentration were ranged from 0.0511-0.2026mg/L in Orange juices; ND-0.0700mg/L in Mango juices; ND for all selected samples in Apple juices; ND-0.0287mg/L in Lychee juices. The concentration of hazardous element Lead was found below detection limit in all selected packaged fruit juice samples. The heavy metals concentration in selected brand of packaged fruit juice samples was in following order: Fe&gt;Zn&gt;Cu&gt; Pb. Int. J. Appl. Sci. Biotechnol. Vol 12(3): 158-165.

The phenotypic and demographic response to the combination of copper and thermal stressors strongly varies within the ciliate species, Tetrahymena thermophila.

Copper pollution can alter biological and trophic functions. Organisms can utilise different tolerance strategies, including accumulation mechanisms (intracellular vacuoles, external chelation, etc.) to maintain themselves in copper-polluted environments. Accumulation mechanisms can influence the expression of other phenotypic traits, allowing organisms to deal with copper stress. Whether copper effects on accumulation strategies interact with other environmental stressors such as temperature and how this may differ within species are still unsolved questions. Here, we tested experimentally whether the combined effect of copper and temperature modulates traits linked to demography, morphology, movement and accumulation in six strains of the ciliate Tetrahymena thermophila. We also explored whether copper accumulation might modulate environmental copper concentration effects on phenotypic and demographic traits. Results showed high intraspecific variability in the phenotypic and demographic response to copper, with interactive effects between temperature and copper. In addition, they suggested an attenuation effect of copper accumulation on the sensitivity of traits to copper, but with great variation between strains, temperatures and copper concentrations. Diversity of responses among strains and their thermal dependencies pleads for the integration of intraspecific variability and multiple stressors approaches in ecotoxicological studies, thus improving the reliability of assessments of the effects of pollutants on biodiversity.

Effects of Different Doses of Biochar Applications on Yield and Nutrient Element Concentrations on Wheat Grown under Salt Stress

In the study, the effects of different doses of biochar applications on the yield and nutrient uptake of wheat grown under salt stress in greenhouse conditions were investigated. The study was conducted in 2 kg capacity plastic pots with three replications using a random plot design. In the study, salt doses were applied as 0 dS m-1, 6 dS m-1 and 12 dS m-1 (in the form of NaCl), and biochar doses (BC) were applied as 0%, 0.5%, 1% and 2% W/W. At the end of the study, the dry matter yield of wheat plant and sodium (Na), nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), zinc (Zn), manganese (Mn), iron (Fe) and copper (Cu) concentrations were determined. Study results showed that BC applications increased the dry matter production of the plant, and the highest was obtained with 2% BC application at 6 6 dS m-1 salt dose, 1.85 g pot-1. However, due to increasing salt doses, BC applications had no effect on the phosphorus and potassium concentrations of the wheat plant, except for calcium, and decreases were determined in the average values. In the study, although all BC applications increased iron, zinc, manganese and copper concentrations compared to the control, when evaluated in terms of average values, decreases were detected in the microelement concentrations of the plant due to increasing salt doses

Study Soil Contamination Surrounding The Brick Factory In Al- Saniyah/ Al- Diwaniyah / Iraq

The study was conducted on the effect of the brick factories in Saniyah on the surrounding soil, with dimensions of 50 m, 500 m, and 1000 m, depending on the direction of the prevailing winds and opposite to the direction of the prevailing winds as well, at 50 m, 500 m, and 1000 m. The concentrations of lead and copper were measured in the soil in two phases : exchangable and residual. The highest concentrations were for lead in the winter. In the alternating part towards the wind, it reached 36.15, and the lowest concentration was in site 5, opposite the direction of the wind. As for the copper element, its highest value was 4.76 in the third site towards the wind, and the lowest value was 1.1 at a distance of 50 m from the chimney, against the direction of the wind. We note that for both elements, the residual phase value is higher than The value of exchangable phase in the direction of the wind is higher than in the opposite direction.

Study of hybrid nanofluid flow in a porous medium over an exponentially stretching sheet under Joule heating and thermal radiation: Finite difference

The significant purpose of present investigation of the behavior of a nanofluid's in magneto-hydrodynamics (MHD), mass transfer, Joule heating, and boundary layer transfer characteristics over an exponentially stretching sheet in a porous medium and thermal radiation effects. The article's goal is to look at the fluid flow and heat transmission characteristics from a sheet of hybrid nanoparticles. The partial differential equations (PDEs) that were derived for the mathematical model were converted using the proper similarity transformation into ordinary differential equations (ODEs). The hybrid nanofluid composed of 97 % of ethyl glycol (EG) and the volume concentration of Magnetite (Fe3O4) and Copper(Cu) are ranging from 0.5 % to 2.5 % both respectively. The effects of thermal radiation, stretching rate, Joule heating, porous medium permeability, and nanoparticle volume fraction on the flow and heat transmission properties are investigated by numerical simulations using the finite difference method (FDM). The analysis reveals that the inclusion of nanofluids enhance the thermal conductivity and enhance the heat transfer rate. Additionally, the influence of variable viscosity on the flow behavior and thermal characteristics are examined graphically. The effects of variable viscosity and thermal conductivity are examined, as it has significance in optimizing system under various thermal and magnetic effects. This study offers a pathway to develop more efficient thermal management solutions, by contributing to technological advancement and energy saving. The key findings of present study reveal that the temperature profile rises significantly due to Joule heating effects. The Nusselt number reveal an improvement of about 12 % when the volume fraction of nano particles is increased by 1–4 % indicating the enhancement in heat transfer efficiency. Similarly, the velocity profile was influenced by porous medium permeability as 11 % increase in porosity result a 18 % decrease in velocity profile.By using parametric research, the role of physical parameters in determining the local skin-friction coefficient, temperature, nanoparticle volume percentage, and longitudinal velocity profiles, local Nusselt number, and local Sherwood number are thoroughly examined. A graphic representation of the velocity, temperature, and concentration distribution findings is presented.

Serum CD5L as potential biomarker of thyroid hormone status during pregnancy.

The thyroid hormone (TH) status is routinely assessed by thyrotropin (TSH) and thyroxine (T4). Both biomarkers are mainly regulated by TH receptor beta, whereas many peripheral organs employ the alpha receptor. Serum cluster of differentiation 5-like molecule (CD5L) is a liver-derived protein under control of both TH receptor isoforms. However, clinical data on its relation to TH status are sparse. An additional biomarker of TH status is needed in particular during pregnancy, where the routine biomarkers become dynamically disturbed. This study aimed to determine possible covariates regulating serum CD5L and to test its potential suitability as additional TH biomarker during pregnancy. A sandwich ELISA for serum CD5L was established using newly raised antibodies. Circadian effects and the impact of liver disease on serum CD5L concentrations were assessed. Serum samples from pregnant women with well-characterized TH and trace element status were analyzed, and CD5L concentrations were correlated with other indicators of TH status including TSH, fT4, fT3, copper, and selenium concentrations. The new quantitative assay for CD5L showed high accuracy. Serum CD5L was stable in dilution and refreezing experiments and did not show strong circadian variance or dependency on liver disease. In serum of pregnant women, CD5L correlated positively to fT3, but not to fT4 or TSH. Significant positive correlations of CD5L were observed with serum levels of the TH-responsive trace elements selenium and copper. The data support the potential suitability of serum CD5L as an additional marker of TH status, with potential value for pregnancy and thyroid disease.

Ameliorating effects of natural herbal supplements against water-borne induced toxicity of heavy metals on Nile tilapia, (Oreochromis niloticus)

The efficacy of herbal supplements in mitigating heavy metals (HMs) toxicity was investigated using a widely grown fish, the Nile tilapia (Oreochromis niloticus). The experiment was conducted over two phases: during the stress phase, the experimental fishes were exposed to sub-lethal concentrations of HMs, including lead, cadmium, zinc, and copper for 15 days; following which during the feeding phase, herbal supplements were given for 70 days to ameliorate their effects. Seven groups were established: the control negative group (CON−ve), control positive group (CON+ve, without any treatment), and five groups with supplementation of 1% turmeric (TUR), cinnamon (CIN), ginger (GIN), garlic (GAR), and their mixture (MIX), respectively. A total of 315 fishes were distributed evenly in experimental tanks (15 fishes per tank, in triplicates). The results revealed that exposure to HMs led to significant (p < 0.05) alterations in all the tested parameters, i.e., liver damage and growth reduction. The herbal supplements, especially the MIX groups, ameliorated the harmful effects of HMs and restored fish growth, digestibility, carcass composition, and liver health. In conclusion, the study demonstrated that the herbal supplements were effective in reducing the HMs-linked toxicity in Nile tilapia. Future studies pertaining to the mechanisms facilitated by the various herbal bioactive substances-linked tolerance to HMs in fishes are warranted.

Risk assessment of heavy metals (Zn, Cu, Pb, and Ni) in the edible tissue of Oncorhynchus mykiss trout in the rivers of the southern Caspian Sea and the northern and southeast coast of Iran

The study aims to monitor and compare the concentration of heavy metals viz., zinc, copper, lead and nickel in the edible tissue of Oncorhynchus mykiss trout in the southern coast of Caspian Sea and the rivers of Khash city in the north-southeast coast of Iran. The average concentrations of zinc, copper, lead and nickel for the Stations in the north of Iran and the southeast of Iran were found 10.1, 8.1, 5.9, 4.7 and 6.5, 6.1, 3.5, 3.2 μg/g dry weight, respectively. Lead exceeded was the recommended standard limits by WHO, FAO, NHMRC, EC and UKMAFF. Based on the results, the average nickel metal was higher than the allowed concentration of international standards in all the studied stations, which indicates that more control should be done on the sources producing this metal around the target areas. furthermore, the daily intake (EDI) of the studied metals in all age groups were lower than the reference dose determined by the EPA organization and the tolerable intake (TI) provided by the FAO/WHO organization. The lowest frequency of daily consumption of Oncorhynchus mykiss was reported for the group of adult males and based on nickel metal (1.67 μg/g) and lead metal (1.14 μg/g) in the rivers located in the south of the Caspian Sea and the rivers of Khash city located in the southeast of Iran, respectively. The risk potential and risk index for non-cancerous diseases for all age groups in the muscle tissue of this fish was less than one, which shows that the consumption of this type of fish for human consumption will not cause a problem from the point of view of health and public health. However, management measures are necessary to prevent and control pollutants, especially in the southern shores of the Caspian Sea.

Beneficial or detrimental? How nickel application alters the ionome of soybean plants

The use of nickel (Ni) in agriculture may represent one of the most significant cases of plant hormesis ever reported, as plants exhibit both positive and negative responses depending on the level of exposure to this element. For a more comprehensive understanding of this effect, the next step is to conduct studies on the dynamics of pre-existing chemical elements in the system (ionomic profile), especially when introducing Ni as a novel nutrient for the plants. This micronutrient is of particular interest to the fertilization of leguminous plants, such as the soybean, due to its additional effects on the biological nitrogen fixation process. This study thus evaluated the influence of five doses of Ni (0.0, 0.5, 1.0, 3.0, and 9.0 mg of Ni kg−1) on the ionomic profile of soybean genotypes using modern quantification techniques. The results revealed that the addition of Ni reduced the concentration of cationic micronutrients manganese (Mn), iron (Fe), zinc (Zn), and copper (Cu), while it increased the concentration of macronutrients nitrogen (N) and magnesium (Mg). The application of Ni also resulted in a reduction of the potentially toxic element aluminum (Al). Correlations were also observed for these elements, indicating that Ni could be a controlling agent in elemental absorption and translocation. The ionome of the leaf tissues exhibited the most significant alterations, followed by the grains, nodules, and roots. Exogenous agronomic doses of Ni proved beneficial for the growth and production of soybean plants, although a genotypic effect was observed. The treatment with 9.0 mg of Ni kg−1, resulted in a new ionomic profile related to toxicity, demonstrating suboptimal plant development. Thus, the application of Ni in appropriate doses had a significant impact on the ionomic profile of soybeans, improving plant development and implying resistance to potentially toxic elements such as Al.

Selective fluorescence sensors for Cu2+ and Hg2+ ions using acridinium-polymer complexes

The photophysical properties of two acridinium derivatives, 9-phenyl-10-methylacridinium (Ph-Arc+) and 9-mesityl-10-methyl acridinium (Mes-Acr+) were investigated in aqueous solutions of poly(methacrylic acids) (PMAA) at various pH values with various polymer to dye (R/D) ratios. In acidic conditions, PMAA effectively turned on the emission of both acridinium derivatives. Micromolar concentrations of copper (II) ions can selectively turn off the emission of dye/PMAA mixtures with a linear response range from 0.50 to 10.0 µM and a detection limit as low as 0.38 µM. In near neutral conditions, Mes-Acr+ in PMAA solutions displayed extremely weak emission. However, trace amounts of Hg2+ ions can instantly turn on the emission with a low detection limit of 43.6 nM and a linear range between 1.0 to 10.0 µM. This analytical method is fast, cost-effective, and environmentally friendly, as it is conducted in 100 % aqueous solution with commercial acridinium derivatives and a biocompatible polymer.

Assessment of Essential Trace Elements Cu, Zn, Mn, and Ni in Mediterranean Mussels (Mytilus galloprovincialis) from the Algerian Coast.

The aim of this study was to determine the levels of essential trace elements copper, zinc, manganese, and nickel in two size groups of mussels, Mytilus galloprovincialis, sampled from three sites along the Algerian coast with different levels of pollution. The results of this work are very interesting for determining the effect of mussel size on the variation of contaminant levels in environmental monitoring studies. Thirty individuals from 2 size groups, less than 4-cm and more than 4-cm shell length, were collected over 4 seasons at each site studied. The samples were dissected, and copper, zinc, manganese, and nickel were measured in the whole soft tissues by inductively coupled plasma mass spectrometry (ICP-MS). The maximum concentrations of copper, zinc, manganese, and nickel expressed in mg/kg dry weight at the three sites were 54.01, 146.25, 20.69, and 8.85, respectively. A clear distribution pattern of the studied elements was observed in the two size classes. In fact, significantly higher concentrations (P < 0.05) were found in individuals with a shell length of less than 4 cm. Significantly, higher concentrations (P < 0.05) were found in individuals with a shell length of less than 4 cm due to their high filtration and low excretion activities compared to long individuals. In addition, metal pollution index (MPI) values were higher in small bivalve individuals. The trace element contents found in the mussel samples of the present study showed large spatial and temporal variations among the different sites studied, highlighting the typical exposure of marine sites to different marine pollutants. Notably, elevated concentrations of copper were observed in the port of Zemmouri, likely due to port activities. Conversely, the highest levels of manganese and nickel were recorded at Boudouaou El Bahri, potentially attributable to the use of fertilisers by agricultural activities. Some shellfish samples had exceeded the permissible concentration levels of copper and manganese, thereby posing a danger to bivalve consumers.

Projections of non-exhaust emissions from brake wear across Japan for 2020–2050

The concerns regarding the detrimental impacts of the increasing proportion of non-exhaust emissions are growing, even though there is a decrease in exhaust emissions from vehicles worldwide. Brake wear is a source of non-exhaust emissions. Despite the high density of traffic in Japan, the emission from brake wear has rarely been the target of studies. The objectives of this study are to estimate the environmental concentrations of copper (Cu) and antimony (Sb) released from brake wear in Japan and compare these concentrations on an annual basis (from 2020 to 2050). The Cu content in brake pads is estimated to decrease greatly from 2021 to 2025, whereas the Sb content is estimated to a moderate level by 2050. In this study, we used an atmospheric dispersion model to predict the reduction in Cu and Sb concentrations emitted from vehicles; owing to the transition to electric vehicles equipped with regenerative brakes (which will generate fewer wear particles), the Cu and Sb emissions in 2050 will decrease by 98 and 89 %, respectively, compared to the emissions noted in 2020. However, the contribution of conventional and electric vehicles to Cu and Sb concentrations will reverse in 30 years, owing to the country's goal that electric passenger vehicles will account for 100 % of the new-vehicle sales by 2035. By 2050, the contribution of conventional vehicles to Cu and Sb concentrations will be only 1 and 3 %, respectively, which will be from conventional vehicles supplied to the market by 2034. Thus, based on the future estimates of the number of vehicles and the composition of their brake pads, we predicted the environmental concentrations of Cu and Sb released from brake wear. The projections presented in this study can serve future interdisciplinary studies on environmental pollution, anthropological emissions reduction, and sustainable development.

Quantitative analysis of copper-molybdenum slurries based on low energy pulse laser, combined with artificial neural network and principal component analysis

In the mining industry, flotation serves as a critical step in the on-stream processing of slurry. A prompt and accurate acquisition of target elemental concentrations is fundamental for evaluating the efficiency of the flotation process. In this study, an algorithm of principal component analysis (PCA) combined with an artificial neural network (ANN) was proposed. This algorithm was based on a low energy pulse laser and a micro-spectrometer, incorporating the principle of laser-induced breakdown spectroscopy (LIBS). The method optimized the number of features for training the models, assisted by cross-validation. The copper concentrations of 36 slurries containing mixed copper-molybdenum powders were quantified. Compared to the full-spectrum model, the full-spectrum PCA model reduced the number of features from 271 to 5 while maintaining an appropriate fit. Meanwhile, the effect of the continuum on prediction accuracy was also analyzed, revealing that the continuum improved the prediction accuracy. This improvement can be explained by the fact that the continuum contains essential information, which serves as a correction for the intensity of the spectral lines. The results indicated that the prediction accuracy of the full-spectrum PCA model was significantly enhanced in comparison to the peak intensity and full-spectrum models, with the correlation coefficient (R2) of the test set improving from 0.894 to 0.985 and the root mean square error (RMSE) decreasing from 0.18% to 0.08%.