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This study sought to clarify whether suspended particles containing high Cu concentrations are present in the sea-surface microlayer (S-SML). For this reason, suspended particles (10–2000 μm) in the S-SML were collected periodically from a ship mooring pond during 2018–2020, and the acid-soluble Cu concentration in the suspended particles was measured as particulate Cu (P-Cu). The highest concentration of P-Cu in the S-SML of the pond was 75 μg L−1 with a 90th percentile value of 2.5 μg L−1. This is below P-Cu values reported for the S-SML in North American ports, but 140 times higher than this found in bulk seawater in the Atlantic Ocean. The highest P-Cu concentration in the S-SML of non-organism (abiotic) origin was 17 μg L−1, and the abiotic P-Cu to P-Cu ratio varied from 0.2 to 100%, likely depending on the quality and quantity of biogenic material in the S-SML samples. It is assumed that the S-SML particles examined here contain high Cu concentrations originating from ship antifouling paints.

Graphical abstract, Environmental structure describes physical structure that can determine heterogenous spatial distribution of biotic and abiotic (nutrients, stressors etc.) components of a microorganism’s microenvironment. This study investigated the impact of micrometre-scale structure on microbial stress sensing, using yeast cells exposed to copper in microfluidic devices comprising either complex soil-like architectures or simplified environmental structures. In the soil micromodels, the responses of individual cells to inflowing medium supplemented with high copper (using cells expressing a copper-responsive pCUP1-reporter fusion) could be described neither by spatial metrics developed to quantify proximity to environmental structures and surrounding space, nor by computational modelling of fluid flow in the systems. In contrast, the proximities of cells to structures did correlate with their responses to elevated copper in microfluidic chambers that contained simplified environmental structure. Here, cells within more open spaces showed the stronger responses to the copper-supplemented inflow. These insights highlight not only the importance of structure for microbial responses to their chemical environment, but also how predictive modelling of these interactions can depend on complexity of the system, even when deploying controlled laboratory conditions and microfluidics.

The modern metals industry is characterised by a downward trend in the quality of ores involved in processing, and conventional methods of extracting useful components are inefficient for raw materials with complex composition. To maintain the growing level of metal production it is required to introduce new efficient technologies for processing of low-grade and refractory ores as well as man-made deposits. The article describes processing methods of refractory raw materials with high cyanide content using copper-gold ores as an example, where gold is the primary commodity, and copper is the accompanying useful component. The most common method of processing copper-gold ores is preconcentration followed by selective leaching of copper and gold. In some cases, technologies involving copper by-products and cyanide recovery from the cyanide leaching solutions offer equally effective options for processing of the copper-gold ores and concentrates. Copper-gold ores are processed at gold mines using the cyanide procedures, supplemented if required by gravity and flotation concentration. In all variations of the cyanide treatment, most of copper minerals actively react with cyanides of alkali metals, binding the CN– ions into the copper complex of [Cu(CN3)]2–. This reaction results in an increased solvent consumption, as well as in number of challenges related to cleaning tailings and slurries from highly toxic cyanide compounds and dissolved copper. In addition to technological complications associated with the need to meet strict requirements for the maximum permissible concentrations, copper accumulated in the cycling solutions also causes a decrease in gold extraction from the processed ores.

To further investigate the influence of temperature and copper content on the carbon brush on the current-carrying friction of the carbon brush/friction disc contact pair. In this paper, the wear performance of five carbon brushes with different copper contents at two types of temperatures was discussed. The tests were carried out on a pin-disc type wear tester with a heating system. The results show there is a critical copper content that affects the friction performance of carbon brushes by influencing the integrity of the friction film. As the test temperature increases, the wear rate of the test samples in the high copper content group increases dramatically.

Gold recovery process is well known. The following paper presents the problematic related to the influence of Copper and Arsenic on the recovery of gold in the Yalea deposit. Multielement tests (Au, Cu, As) carried out on 37 blocks made it possible to understand that there is a correlation between these elements. This correlation has been observed since the analysis of block models (the block model for Copper, block model for Arsenic and the block model for gold. These models have shown that the Yalea deposit areas with a high gold content correspond to areas of high copper content and arsenic. Those who made it clear that copper and Arsenic are tracing elements of Gold in the Yalea deposit. In this paper, the mineralurgical tests carried out on 28 blocks revealed that the copper and the arsenic content in the ore penalize the recovery of Gold (146 ppm for copper and 4710 ppm for Arsenic). The Yalea deposit was emplaced by several hydrothermal phases that reactivated the structures. These phases are responsible for the establishment of large quantities of copper sulphides. Copper and Arsenic are elements that have a considerable influence on the gold recovery in the Yalea deposit.

This study investigated the relationship between subjective forgetfulness and the dietary intake of various nutrients in middle‐aged and senior women. A cross‐sectional study of the first‐visit records of 245 Japanese women aged 40 or over was performed. The severity of subjective forgetfulness was classified according to the Menopausal Health‐Related Quality of Life Questionnaire: none and mild (“unforgetful”) or moderate and severe (“forgetful”). Dietary consumption of nutrients was estimated using the brief‐type self‐administered diet history questionnaire. The associations between the severity of subjective forgetfulness and intake of 43 major nutrients were evaluated using multivariate logistic regression analysis separately performed for two age groups: middle‐aged (40–54 years, N = 166) and senior (55 years or over, N = 79). No nutrients were found to be significantly associated with subjective forgetfulness in the middle‐aged group. In senior women, a significant positive relationship between the intake of copper and forgetfulness was found (adjusted odds ratio per 10 mg/kJ increase in copper intake: 1.25; 95% confidence interval: 1.08–1.50). Thus, high copper intake is positively associated with the severity of forgetfulness in Japanese senior women. Reducing copper consumption could help improve this symptom in this population., We examined the nutritional factors associated with subjective forgetfulness. Participants were Japanese middle‐aged and elderly women. High copper intake is positively associated with the severity of forgetfulness in Japanese senior women.

Os metais são reconhecidos pelo caráter potencialmente tóxico às comunidades além de bioacumulativos em alguns organismos. No presente trabalho, avaliou-se as concentrações dos metais cádmio, cromo, cobre, chumbo, mercúrio e zinco em sedimentos de três pontos de amostragem nos reservatórios Billings, Guarapiranga e Rio Grande (São Paulo, Brasil) entre os anos 2008 e 2017. Os dados foram comparados à valores de referência regionais, à legislação local e a valores guia de qualidade de sedimento: nível de efeito limiar (TEL), nível de efeito provável (PEL) e Critérios de Avaliação dos Sedimentos (CQS). Amostras de sedimento do reservatório Billings apresentaram os maiores números de metais acima dos valores de referência e acima de PEL. Observou-se elevadas concentrações de cobre nos reservatórios Guarapiranga e Rio Grande, provavelmente em decorrência do sistema de gestão aplicado no local à base de Sulfato de Cobre Pentahidratado. Os dados analisados aqui, indicam que a falta de índices regionalizados, com valores de background e critérios de toxicidade para o sedimento, específicos para esses reservatórios é uma grande deficiência para análises mais acuradas e preditivas. Ainda assim, fica demonstrado que os níveis atuais de contaminação dos sedimentos dos reservatórios estão reduzindo a qualidade da água e pressionando negativamente a biota local e alterando e comprometendo o ecossistema aquático.

In spite of their similar structures, the catalytic properties of natural and synthetic (SSZ-13) Chabazite during the selective reduction of NO with NH3 have a different dependence on the Cu exchange level when tested under conditions equivalent to those found in Diesel vehicles. At low (1-2 wt.%) and high copper loadings (6-14 wt.%), their activities differ, because there are variations in the different species of Cu (Cu+, Cu2+, Cu-O-Cu) detected by UV-Vis. At intermediate Cu loadings (2-3 wt.%) they have similar high activities, reaching 100 % conversion. High deNOx activity per Cu site appears to correlate with the predominance of charge compensation Cu2+ species over CuOx moieties. There are changes in the distribution of Cu moieties during operation of both catalysts, evidenced by DR-UV-Vis. Resumen. A pesar de sus estructuras similares, las propiedades catalíticas de Chabazita natural y sintética (SSZ-13) durante la reducción selectiva de NO con NH3 dependen de manera diferente frente al nivel de intercambio con Cu cuando se prueban bajo condiciones equivalentes a las de vehículos Diesel. A bajos (1-2 % p/p) y altos contenidos de Cu (6-14 % p/p) la reducción de NO es diferente debido a variaciones en las distintas especies de Cu (Cu+, Cu2+, Cu-O-Cu) observadas por UV-Vis. Por su parte, los catalizadores intercambiados con 2-3 % p/p de Cu tuvieron alta actividad por sitio de Cu, alcanzando 100 % de conversión de NO, lo que parece deberse a la predominancia de especies de Cu2+ sobre especies CuOx de acuerdo con el análisis por DR-UV-Vis, el que también muestra la existencia de variaciones en la distribución de especies de Cu debido a la reacción.

International audience; This article aims to assess the impact of copper availability on the energy transition and to determine whether copper could become critical due to the high copper content of low-carbon technologies compared to conventional technologies. In assessing copper availability through to 2050, we rely on our linear programming world energy-transport model, TIAM-IFPEN. We examine two climate scenarios (2 °C and 4 °C) with two mobility shape, implemented with a recycling chain. The penetration of low-carbon technologies in the transport and energy sectors (electric vehicles and low-carbon power generation technologies) is likely to significantly increase copper demand by 2050. To investigate how tension over copper resources can be reduced in the energy transition context, we consider two public policy drivers: sustainable mobility and recycling practices. Results show that in the most stringent scenario, the cumulative primary copper demand between 2010 and 2050 is found to be 89.4% of the copper resources known in 2010. They also pinpoint the importance of China and Chile in the future evolution of the copper market.

A handheld XRF-analyzer specially calibrated for measurements of metals on plastic boat hulls has been used on leisure boats in Denmark (DK), Finland (FI), and Germany (DE). The results on tin and copper are presented as μg metal/cm2. Tin is a proxy for the occurrence of organotin compounds on the boat. Two or three sites were visited in each country and between 25 and 90 boats were measured at each site. Every boat was measured at six to eight places, and the results are presented both as mean and median values. Linear regression of mean to median values of the 377 data pairs shows high relationship with R2 = 0.9566 for tin and R2 of 0.9724 for copper and thus both ways of calculation may be used. However, for regulative use, it is suggested that all individual measurements on each boat should be presented and used for decisions of removal or sealing of boat hulls. The results are compared with published data from different parts of Sweden, i.e., boats in fresh water, brackish water, and salt water. The results show that tin with mean values > 50 μg Sn/cm2 is still found on 42, 24, and 23% of the boats in DK, FI, and DE, respectively. The corresponding percentages based on median values are 38, 22, and 18% for DK, FI, and DE, respectively. The variation among boats is high with a maximum mean value of 2000 μg Sn/cm2. As comparison, one layer of an old TBT antifouling paint Hempels Hard racing superior, corresponds to 300 μg Sn/cm2. The percentage of boats with tin > 400 μg Sn/cm2 content based on mean values was 10% in DK, 5% in FI, and 1% in DE. The corresponding median values were 9, 6, and 1% for DK, FI, and DE. Copper, > 100 μg Cu/cm2, was detected on all measured boats in DK and in DE and on all but 3% of the FI boats. One layer of Hempels MilleXtra corresponds to ~ 4000 μg Cu/cm2. The recommendation on the can is to apply two layers. The proportion of boats with higher mean copper values than 8000 μg Cu/cm2 was 51, 56, and 61 for boats in DK, FI, and DE, respectively. The proportion based on median values > 8000 μg Cu/cm2 was 50, 54, and 61% for DK, FI, and DE. The conclusion is that many leisure boats around the Baltic Sea still display or possess antifouling paints containing organotin compounds and that more than half of the boats have more copper than needed for one boat season according to the paint producers. Much of these known toxic compounds will probably be released into the environment and harm the biota. The calibrated XRF-method, intended for area measurements on boat hulls, is an easy and cheap way to detect boats with organotin compounds and high copper content. We recommend environmental authorities to use this method for identification of such boats and to use the results for requesting measures to minimize further leakage to the environment.

the main goal of this present investigation is to study the effect of the (Al2O3) addition on corrosion resistance and dimensional change of the high copper dental amalgam. One alloy has been prepared via casting composed of silver (47%), tin (30%), copper (22%), and zinc (1%). (Al2O3) addition is added in distinct percentages of the (0.5, 1, 1.5, 2) wt.%. Specimens were prepared according to ADA specification No. 1. The specimens have been stored at 37±1 C° using a chamber prepared for this purpose. corrosion resistance improved with addition from 0.5% to 2% (Al2O3) and observed that dimensional change of amalgam improved after (Al2O3) additions.

The ability of soft rot fungi possessing strong (Phialophora malorum), medium (Phialophora mutabilis) and poor copper tolerance (Chaetomium globosum) to degrade untreated and CuSO4 and micronized copper treated birch- and pine wood was assessed using ENV 807 standard tests. The aim was to determine whether an ability to grow on Cu-agar and copper in liquid cultures can be transcribed into a competitive advantage to degrade Cu-treated wood. An ability to tolerate high copper levels in-vitro was not correlated with increased decay by the fungi but rather reflected the native chemistry of the wood cell walls. Both untreated and Cu-treated wood were degraded by the three fungi and showed aggressiveness in the order C. globosum > P. mutabilis > P. malorum Higher mass loss was recorded for birch than pine and decreased progressively as the copper loadings increased with statistically insignificant difference noted between Cu-treatments. Microscopy showed decay at the cell wall level to reflect degree of lignification with parenchyma cells degraded first in both untreated and Cu-treated wood. Results indicate presence of copper and its toxicity is unlikely to be the main reason for preventing soft rot decay of wood but rather the additive effect of copper binding to the wood material.

In the restoration of lost or damaged dental pieces, different alloys are frequently used, leaving the mouth exposed to electrical currents that circulate through saliva and dental fluids. In the present work, electrochemical methods are used to determine the corrosion rate of galvanic pairs of a high copper silver amalgam with Co-Cr dental alloys in artificial saliva. It is observed that when the difference in corrosion potentials of dissimilar alloys are small (less than 100 mVecs), Evans diagrams do not give good results, so the Mansfeld correction formulas must be used. Thus, it is found that the most resistant to corrosion is the pair formed between the amalgam and the bulk Co-Cr alloy (PG1,3) and that the corrosion products released in greater quantity to the electrolyte are those that contain ions of Co, Cr, Ag, Sr and Cu. Keywords: Corrosion, dental alloy, polarization curve, artificial saliva, galvanic pair.

A coated copper sulfate algicide designed for controlled release of copper was evaluated for its effectiveness in controlling phytoplankton in hybrid catfish, ♀Ictalurus punctatus × ♂Ictalurus furcatus, ponds. Copper concentrations were greater in ponds receiving weekly treatments with copper sulfate crystals than in ponds in which the coated copper sulfate was suspended in porous bags and left in ponds during the study. However, the coated copper sulfate treatment provided a similar degree of phytoplankton control for a period of about 4 mo. Copper additions did not negatively affect catfish survival, production, or feed conversion in either the copper sulfate crystal treatment or in the coated copper sulfate treatment as compared with the control (P > 0.05). Flavor scores for fish did not differ between control and treatments (P > 0.05). The coated copper sulfate appeared to be a potentially effective method for controlling phytoplankton in aquaculture ponds. It would be easier to apply and require fewer applications, and the coated copper algicide would not present a fish toxicity issue that can arise from high copper concentration immediately following copper sulfate crystal treatment.

In the process of cyanidation of gold concentrate from a smelting company, the content of copper and zinc in the liquid gradually increased. In production, acidizing process is used to treat the lean solution from high copper concentrate, and mixed products containing copper, zinc and other metals are produced. In this paper, the pH value of zinc precipitation is 6.0 and the pH value of copper precipitation is 3.0 through theoretical calculation and experiment. The separation of copper and zinc in the lean solution is realized successfully. The zinc product with grade of 42.97% and the copper product with grade of 58.33% are produced.

Thin materials exhibiting the shape memory effect, with a narrow temperature hysteresis, are required to create miniature and high-speed devices. Quasi-binary intermetallic TiNi-TiCu alloys with high copper contents (more than 10 at %) demonstrate the reversible martensitic transformation with a small (4-6 K) hysteresis. Alloys of the TiNi–TiCu system with a copper content of 30–40 at.% were fabricated in an amorphous state by the planar flow casting technique at a melt cooling rate of 106 K/s in the form of ribbons 30–50 μm thick. The alloy samples were subjected to dynamic crystallization using a single electric current pulse with duration of 5 ms. X-ray diffraction studies revealed almost fully martensitic state of the alloys with B19 structure at room temperature. TEM examination showed their structure to contain typical B19-martensite plates with a mean size of 20–80 nm. At the same time, the alloys exhibit a one-stage phase martensitic transformation B2↔B19 in the temperature range of (55÷75)°C, as well as pronounced shape memory effect, whose properties are largely determined by the structural parameters of the alloys.

The rapidly quenched alloys of the quasibinary intermetallic TiNi-TiCu system with a high copper content (more than 25 at.%) are of great interest as shape memory materials due to the possibility of a significant decrease in the temperature and deformation hysteresis in comparison with the binary TiNi alloy. To obtain alloys with a copper content of 25 to 40 at.%, the planar flow casting technique was used. The alloys were fabricated at a melt cooling rate of about 106 K/s in the form of ribbons 30-50 μm thick and wide in the range from 7 to 20 mm. The study of the structure of the alloys was carried out using X-ray diffraction analysis, scanning and transmission electron microscopy. It was shown that from the ribbon side, contacting the quenching wheel, all alloys are amorphous, while on the non-contact side of the ribbons of alloys with 25 and 30 at.% Cu, a thin surface crystalline layer with a B2 structure is observed. Using energy dispersive X-ray spectroscopy, it was found that the content of the alloy components in the amorphous and crystalline phases coincides.

Nanoscale Cu-rich precipitates that were formed in Cu-containing reactor pressure vessel (RPV) steels during service have a deleterious effect on mechanical properties, which can result in RPV embrittlement and limit reactor operation life. To understand the nanoscale precipitation mechanism, thermal aging at 370°C for up to 13200 h of high-copper RPV model steels was performed to produce nanosized Cu-rich precipitates. Then the Cu-rich precipitates were systematically investigated by atom probe tomography (APT). The changes in the mechanical properties of the steels were characterized by Vickers hardness test. The results show that the Cu-rich precipitates as determined by APT construction analysis have a spatial core-shell structure. The core is enriched with Cu atoms, and the region near the precipitate/matrix interface is enriched with Mn, Ni, Mo, and Si and C atoms. Cu-rich precipitates lead to precipitation strengthening and hardening/embrittlement effects. Using the Russell-Brown model, we estimated the hardening due to Cu-rich precipitates in the matrix and observed that the measured hardness and the estimated changes in hardness were in good agreement.

The influence of ammonium humate obtained from peat on the wheat plant tolerance to high CuSO4 concentrations (100, 250, 500, and 1000 μM/l) was studied. Seeds were germinated on copper sulphate solution with and without the humate. Then the plants were grown on Hoagland’s solution in an artificial climate chamber. The humate protective action coefficient was estimated in two ways, namely: by dry weight changes and by copper ion content in comparison with the plants grown without humate. A protective role of the humate at 100 and 250 μM was established, due to copper accumulation reduction in the plants. At higher concentrations the humate enhanced the toxic effect of copper.

High copper (Cu) soil contents, due to the continuous vineyard application of Cu fungicides throughout the years, may impair the growth of the shoot and modify the structure of the root system. The current study aimed to investigate the threshold levels of available Cu in the soil causing toxicity effects in young grapevine plants of ‘Red Niagara’ cultivated in clay soils. Grapevine plantlets were cultivated in pots containing vineyard devoted soils with increasing contents of available Cu (25, 80, 100 and 165 mg kg?1 ), for 53 days. Photosynthesis and transpiration rates, and the quantum yield of photosystem II (Fv/Fm) were evaluated during the cultivation period. At the end of the experiment, the plant nutrient and leaf chlorophyll were determined, along with the anatomical analysis of the root system structure and plant dry matter determination. Higher levels of available Cu in the soil increased the apoplastic, symplastic and total fraction of the metal in the roots, reducing the other nutrients, especially in the shoots. Photosynthesis, transpiration rates and Fv/Fm were also reduced. Higher levels of Cu led to anatomical changes in the roots, that increased diameter, number of layers in the cortex, vascular cylinder and total root areas. It also resulted in reduced dry matter production by grapevines. Keywords: Available Cu Net photosynthesis Maximum quantum yield Root diameter Vitis labrusca L Made available in DSpace on 2019-01-11T00:04:58Z (GMT). No. of bitstreams: 1 Highcoppercontentinvineyardsoilspromotesmodi64257cationsin.pdf: 1434017 bytes, checksum: 77453d1f9f03c8da1881ad6ee30af116 (MD5) Previous issue date: 2019-01-09

Aim: The aim of the present study is to evaluate and compare patient sensitivity following the amalgam restorations using two different materials beneath them - zinc phosphate base and dentin bonding agent. Materials and Methods: Thirty individuals aged between 20 years and 60 years were selected who presented with two class I carious lesions located in different quadrants. Both the teeth were filled at the same appointment. Following rubber dam isolation, conventional cavities were prepared for the amalgam restorations. One tooth received zinc phosphate base while the other received dentin bonding agent beneath the amalgam restoration. High copper non-γ2 amalgam was triturated using amalgamator by condensing it into the cavity. Questionnaires were given to the patients for recording sensitivity scores to heat, cold, or biting at the end of 1, 3, 7, and 14 days. Results: Significance was determined based on the P values obtained from the simple curve z-test. On day 1, when groups I and II were compared, no significant difference in number of patients reporting postoperative sensitivity was found. On day 3, more number of patients reported sensitivity with zinc phosphate cement compared to those with dentin bonding agent. On day 7, there was great reduction in sensitivity in both groups compared to day 1 and day 3 but comparatively more in teeth with zinc phosphate base. On day 14, there was no significant sensitivity in both groups, patients showing no sensitivity to both zinc phosphate base and dentin bonding agent. Conclusion: Postoperative sensitivity was relatively more in teeth restored with zinc phosphate base compared to that restored with dentin bonding agent. Postoperative sensitivity resolved earlier in restorations with dentin bonding agent compared to zinc phosphate base, and sensitivity resolved with time in both the restorations.

Background & Objectives: To evaluate of corrosion products in dentin after removal of old Amalgams with and without roughness Materials and Method: Twenty Class II cavities were prepared on extracted premolars then Randomly were divided into four groups according to how they were restored. Group 1 : Light-cured packable composite to establish a microleakage baseline; Group 2: A high copper Amalgam; then stored in 37 ° C normal saline for 6 months to create amalgam corrosion products. Group 3: Identical to Group 2, but later the amalgam was replaced with composite leaving the cavity walls intact. Group 4: Identical to Group 3 except the cavity walls were extended 0.5 mm after amalgam removal prior to insertion of the composite. There are 5 specimens in each four groups for EDX analysis.Evaluation of EDX analysis was descriptive. Results : Corrosion products were detected in Groups 1,2,3 but were not detected in Group 4 . Conclusions : After amalgam removal, roughing dentinal walls could remove the corrosion products penetrating it. Keywords : Corrosion, High copper Amalgam, Dentin, surface roughing

The present study was carried out to investigate the effect of copper stress on FH 810 and Yousaf wala cultivars of Zea mays. From the study it is cleared that high concentrations of copper had negative effect on growth and photosynthetic attributes of both cultivars, as growth of plant decreased with increasing copper levels, same is the case with chlorophyll and carotenoid contents. FH 810 was more tolerant to copper stress than Yousaf wala cultivar. So, it is recommended that at high copper stress levels cultivation of FH 810 would be promoted than other one.

Descrevem-se casos de intoxicação aguda por cobre em ovinos da raça Santa Inês, numa propriedade rural, no Rio Grande do Sul. Três ovelhas recém-paridas, que consumiam ração formulada para bovinos, ingeriram, avidamente, sal mineral comercial para bovinos e apresentaram doença clínica e morte, uma semana após a introdução do sal. Os animais desenvolveram anorexia, permaneceram em decúbito lateral, o qual evoluiu para esternal e apresentaram fasciculação e rigidez muscular generalizada, antes de morrerem. À necropsia de um desses animais, as principais alterações foram hepatomegalia moderada e acentuação do padrão lobular hepático, além de erosões e ulcerações multifocais aleatórias na mucosa abomasal. Na avaliação histológica do fígado, havia necrose hepatocelular centrolobular acentuada e difusa, tumefação de hepatócitos, predominantemente, na região periportal, além de pequena quantidade de células de Kupffer com pigmento granular citoplasmático. O diagnóstico baseou-se na história clínica, nos achados de necropsia e histopatológicos e confi rmou-se pelas altas concentrações de cobre detectadas no tecido hepático e nas amostras de ração e sal mineral. Cases of acute copper intoxication in Santa Ines sheep are described. The disease occurred on a farm in Rio Grande do Sul. Three ewes that had recently lambed and that were fed cattle diet became severely ill and died one week after ingestion of a commercial mineral mix for beef cattle. The sheep showed anorexia, lateral and sternal recumbency, fasciculation and muscle stiffness and death. At necropsy from one of these sheep, the main changes were moderate hepatomegaly, prominent hepatic lobular pattern, and multifocal randomly distributed erosions and ulcerations on the abomasal mucosa. Histological evaluation of the liver showed marked centrilobular hepatocellular necrosis; diffuse hepatocyte swelling predominantly in the periportal area, and a few Kupffer cells contained cytoplasmic pigment granules. The diagnosis was based on the clinical history, necropsy and histopathologic fi ndings, and confi rmed by the high copper concentrations detected in the liver, feed, and mineral mix samples.

The purpose of this study is to provide a materialization method for high copper-containing wastewater and compare it with conventional chemical precipitation process and ferrite process. In the first stage of mineralization, the copper-containing wastewater was added into a tank with NaOH solution followed by the addition of Fe3+ ion and heated to 70°C. The molar ratio between Fe3+ and divalent metal ions () was given and the pH value of solution was controlled in the strong alkaline range (11.0–11.5). In the inverse mixing method, the whole precipitation process was carried out in the strong alkaline solution, which resulted in the simultaneous precipitation of Fe3+, Cu2+, Ni2+ and Zn2+ ions. The first reaction was complete when the ORP remained constant. Finally, the formation of the magnetic ferrite, Fe2+ ion was added into the solution accompanied by heating and aeration. The magnetic separation could be then used for solid–liquid separation. Therefore, these results reveal that not only the ...

In the early 1980s, attention focused on the possibility that pressurized thermal shock (PTS) events could challenge the integrity of a nuclear reactor pressure vessel (RPV) because operational experience suggested that overcooling events, while not common, did occur, and because the results of in-reactor materials surveillance programs showed that RPV steels and welds, particularly those having high copper content, experience a loss of toughness with time due to neutron irradiation embrittlement. These recognitions motivated analysis of PTS and the development of toughness limits for safe operation. It is now widely recognized that state of knowledge and data limitations from this time necessitated conservative treatment of several key parameters and models used in the probabilistic calculations that provided the technical of the PTS Rule, 10 CFR 50.61. To remove the unnecessary burden imposed by these conservatisms, and to improve the NRC's efficiency in processing exemption and license exemption requests, the NRC undertook the PTS re-evaluation project. This paper provides a synopsis of the results of that project, and the resulting Alternate PTS rule, 10 CFR 50.61a.

As atividades de mineração e de viticultura do Rio Grande do Sul têm contribuído para a contaminação do solo por cobre. Este trabalho objetivou avaliar o efeito de doses de cobre no crescimento e na qualidade de mudas de timbó (Ateleia glazioviana) e dedaleiro (Lafoensia pacari). O delineamento foi inteiramente casualizado em arranjo fatorial (2 x 4), formado de duas espécies florestais e quatro doses de cobre (0, 64, 128 e 192 mg kg-1 de solo) com cinco repetições. Avaliaram-se altura da planta, diâmetro do colo, peso da matéria seca radicular e da parte aérea, comprimento e área superficial específica radicular e os seguintes índices de qualidade de mudas: relação entre altura da parte aérea e diâmetro do coleto; altura da parte aérea e peso da matéria seca da parte aérea e o índice de qualidade de Dickson, em que os resultados revelaram que as doses de cobre testada reduziram a qualidade de mudas do timbó enquanto o dedaleiro apresentou melhor qualidade com 128 mg kg-1 de Cu. O cobre influenciou os parâmetros de crescimento das mudas de timbó porém aumentou significativamente o comprimento e a área superficial específica do dedaleiro até 128 mg kg-1 de Cu. Mudas de dedaleiro são mais tolerantes à contaminação do solo que as de timbó e apresentam melhor qualidade em doses mais elevadas de cobre.

Copper die casting motor (CDM) has a better design flexibility than aluminium die casting motor (ADM) because of the higher conductivity of copper. However, CDM has an economic and manufacturing weak point due to high copper price and high melting temperature compared to ADM. This paper describes a comparison of the design parameters, specifications, performances and material cost between CDM and ADM of 5.5kW_6P.

Copper has a dual role for organisms, both as micronutrient and toxic element. Copper mining activities have an enormous ecological impact because of the extraction process and the consequent release of copper-containing waste materials to the environment. In northern Chile, mainly in the Chañaral coastal area, this phenomenon is clearly evident. The released waste material has caused a strong modification of the area, and copper enrichment of beaches and rocky shores has provoked a decrease in the richness and diversity of many species of macroorganisms. However, the effects that copper enrichment has on microbial (e.g. bacterial epilithic) communities associated with the rocky shore environment are poorly understood. Using a culture-independent molecular approach, field sampling and laboratory microcosm experiments, we determined the effects of copper enrichment on bacterial communities inhabiting the rocky shore environment. Field samples showed a strong effect of copper on the structure of the natural bacterial epilithic communities, and microcosm experiments demonstrated rapid changes in bacterial community when copper is added, and reversibility of this effect within 48 h after copper is removed.

A series of technical improvements have been implemented to address the issue of high copper losses in rotary holding furnace (RHF) slag, which were experienced at the Xstrata Copper Smelter at Mount Isa in 2007 and 2008. The copper losses in smelting slag in the RHF were more than 3% in 2006 and 2007. Thermodynamic models and viscosity models have been applied in the operation of Xstrata Copper Smelter in Australia. The theory of RHF key performance indicators has also been developed to reduce the copper losses in RHF slag. The RHF KPIs Theory has been applied in Mount Isa Copper Smelter. The copper losses in RHF slag dropped from 3.1% in 2007 to 0.76% in April 2009. The average copper loss in RHF slag in 2009 and 2010 was about 0.9%.

Objectifs: L’objectif de cette étude était d’évaluer le comportement de deux variétés de deux légumes installés sur les sols contaminés en ETMs dans la région de Lubumbashi.Méthodologie et résultats: Deux essais suivant un dispositif factoriel 4*2 ont été installés, dont le facteur principal est constitué de deux variantes de laitue et de Gombo (variété améliorée et celle locale) et le facteur secondaire qui 4 variantes de sol dont celui de (de Kipushi, de Pengapenga, de Luwowoshi (Ruashi) ainsi que celui de la ferme Kassapa). Les résultats obtenus dans cette étude montrent que les sols sont contaminés en cuivre et la laitue ayant évoluée sur ces substrats présentent des teneurs en cuivre très élevées dépassant la norme, la variété locale avait présenté un bon comportement contrairement à la variété améliorée venant de la France sur ce qui est de la survie, du taux de levée.Conclusion et applications des résultats: la variété locale de laitue et de Gombo sont les mieux appropriées pour les sols contaminés , toutes fois l’application des amendements organiques et calcaires permettrait d’avantage de réduire la mobilité de cuivre dans le sol et le transfert de ce dernier vers les parties aériennes.Mots clés: Variété, contamination, gombo, laitueEnglish AbstractObjectives: The objective of this study was to evaluate the behavior of two varieties of two vegetables installed on soils contaminated with ETMs in the Lubumbashi region.Methodology and results: Two tests using a factorial 4 * 2 device were installed, the main factor of which consists of two variants of lettuce and okra (improved variety and local variety) and the secondary factor which 4 soil variants including that of (Kipushi, Pengapenga, Luwowoshi (Ruashi) and Kassapa Farm). The results obtained in this study show that the soils are contaminated with copper and lettuce having evolved on these substrates have very high copper contents exceeding the norm, the local variety had exhibited a good behavior contrary to the improved variety coming from France. on what is survival, the rate of emergence.Conclusion and applications des results: the local variety of lettuce and okra are the most appropriate for contaminated soils, all the time the application of organic and limestone amendments would better reduce the mobility of copper in the soil and the transfer of the latter towards the aerial parts.Keywords: Variety, contamination, okra, lettuce

Aim To assess serum Cu/Zn SOD (Superoxide Dismutase) concentration in children with ADHD and evaluate its possible relationship to Cu and Zn levels. Subjects and methods Serum from 22 children with ADHD and 20 healthy control children without ADHD and 19 autistic children without ADHD were tested for Cu/Zn SOD using ELISAs and levels of serum Cu and Zn using inductively-coupled plasma-mass spectrometry. Results Serum Cu/Zn SOD levels of ADHD children were significantly lower than age and gender matched healthy non-ADHD controls ( P < 0.001). Serum Cu/Zn SOD of ADHD children was significantly lower in individuals with high serum copper ( P = 0.024). There was no significant correlation between Cu/Zn SOD levels and Zinc or Cu/Zn in ADHD individuals. Discussion These results suggest an association between Cu/Zn SOD serum levels and ADHD, particularly ADHD children with high serum copper.

Objective—To determine whether metal concentrations in canine liver specimens were influenced by specimen size, assay variability, tissue processing (formalin fixation and deparaffinization), or storage in paraffin blocks. Sample Population—Liver specimens (fresh frozen and deparaffinized) from 2 dogs with chronic hepatitis (high copper but unremarkable iron concentration [liver 1] and unremarkable copper but high iron concentration [liver 2]) as well as fresh and deparaffinized-archived liver specimens from 20 dogs with various hepatopathies. Procedures—Fresh frozen liver specimens (obtained via simulated needle-core and wedge biopsy), fresh hepatic tissue, and deparaffinized-archived specimens (0.5 to 14 years old) were analyzed for concentrations of copper, iron, and zinc by atomic absorption flame spectrometry. Clinical severity scores were assigned on the basis of tissue metal concentrations. Results—Interassay variation of metal standards was < 4%. Measurements of liver tissues on 8 consecutive days yielded high coefficients of variation (3.6% to 50%) reflecting heterogenous histologic metal distribution; variation was highest in liver 1 and deparaffinized-archived tissues. Heterogenous metal distribution was confirmed by histologic evaluation. The largest range of metal concentrations was detected in wedge biopsy specimens. In tissues with high metal concentrations, copper and iron concentrations were significantly lower in needle-core versus wedge biopsy specimens. A higher zinc concentration in deparaffinized-archived specimens masked a low zinc concentration in fresh liver tissue of 10 of 20 (50%) dogs. Conclusions and Clinical Relevance—Retrospective measurement of copper and iron concentrations but not zinc concentrations in deparaffinized-archived liver specimens provided relevant information. The value of needle-core biopsy specimens for measurement of metal concentrations is questionable.

Effect of Increased Copper Concentrations on Deformations of the Regenerates of Carrot Obtained from Androgenetic Embryos The experiment aimed at determining the effect of high copper concentrations on the process of regeneration of carrot plants cv. Feria F1 from androgenetic embryos. The starting material consisted of green embryos obtained in anther cultures on a medium for the induction of androgenesis. Five B5 regeneration media of Gamborg et al. (1968) containing 0.1 (control), 1, 10, 100, and 1000 μM·L-1 CuSO4·5H2O were used. The plant material was passaged onto fresh media 3 times after 4, 9, and 15 weeks from culture set-up date. During the passages, the regenerated structures were examined and categorized according to their growth, development and the course of regeneration in the in vitro culture. The B5 regeneration medium that contained 1000 μM·L-1 CuSO4 was highly toxic for the growth and development of androgenetic embryos of carrot. The other concentrations of CuSO4 that were higher than the level of the control medium, i.e. 1, 10, and 100 μM·L-1, had a negative effect on the regeneration from androgenetic embryos of carrot in the second and third passages (after 9 and 15 weeks). They caused deformations of the leaves and the formation of an abnormal callus heel between the above-ground part and the root.

A total of 216 weanling pigs (PIC TR4 × 1050, initially 13.6 lb and 21 d of age) were used in a 42-d growth trial to compare the effects of supplemental zinc and copper and changing mineral regimens on growth performance and plasma mineral levels. The 6 dietary treatments included a 2 × 2 factorial arrangement with main effects of added copper from copper sulfate (0 or 125 ppm) and added zinc from zinc oxide (0 or 3,000 ppm from d 0 to 14 and 0 or 2,000 ppm from d 14 to 42). For the final 2 treatments, either zinc oxide alone or the combinations of zinc and copper were fed from d 0 to 14, with copper sulfate fed from d 14 to 42. There were 6 pens per treatment with 6 pigs per pen. All diets were supplemented with an additional 165 ppm zinc and 16.5 ppm copper from the trace mineral premix. Plasma was collected from 2 pigs per pen on d 14 and 42. From d 0 to 14, ADG, ADFI, and F/G were improved (P < 0.04) with the addition of dietary zinc. Copper supplementation also tended to increase (P < 0.07) ADFI from d 0 to 14. From d 14 to 42, added copper increased (P < 0.003) ADG and ADFI. Over the entire trial, continuous supplemental zinc increased (P < 0.03) ADG and tended to increase (P < 0.09) ADFI. Dietary copper also increased (P < 0.004) ADG and ADFI when fed from d 0 to 42. The most advantageous values for ADG and ADFI were seen in the treatment containing high levels of zinc from d 0 to 14 and high copper levels from d 14 to 42. The addition of either zinc or copper increased (P < 0.02) feed cost per pound of gain. However, income over feed cost was improved (P < 0.006) with the addition of copper, with the greatest value obtained when high zinc was fed from d 0 to 14 and high copper was fed from d 14 to 42. Plasma zinc levels were increased (P < 0.001) with zinc supplementation on d 14. These results indicate the optimal mineral regimen was supplementing zinc oxide from d 0 to 14 and copper sulfate from d 14 to 42.

Due to environmental concerns and regulatory initiatives, electronics manufacturers are replacing the tin/lead solder commonly used on printed wire boards (PWBs) with alternative solders. To determine the potential waste management impacts of the alternative solders versus the tin/lead solder, two leaching tests on PWBs manufactured with five alternative types of solder were performed: the toxicity characteristic leaching procedure (TCLP) and the synthetic precipitation leaching procedure (SPLP). These tests are commonly used in the US regulatory community to assess pollutant leachability in different disposal scenarios. The article discusses the application and limitations of these tests. The five types of solders investigated were 63Sn/37Pb, 99.3Sn/0.7Cu, 95.5Sn/4Ag/0.5 Cu, 96Sn/2.5Ag/1Bi/0.5Cu, and 42Sn/1Ag/57Bi. The leaching tests were conducted on four PWB sections, each with a unique configuration and solder density. The largest lead concentrations were observed from the PWBs containing Sn/Pb solder, with concentrations exceeding the hazardous waste toxicity characteristic (TC) in TCLP leachates. Silver, the other regulated element used in the solders, was rarely detected, with none of the samples exceeding the TC limit for silver. High copper concentrations were observed and were determined to result from the PWB itself, not from the copper-containing solders.

Recent Cu price increases motivate careful examination of approaches to minimize Cu use in high-frequency transformers and inductors. Approaches that can reduce Cu use without increasing losses include careful winding design, trading winding volume for core volume, replacing Cu with Al, and using Cu-clad Al (CCA) windings. Al wire is particularly attractive. The cost of Al is lower than it might appear from the cost per unit mass when the much lower density of Al is also considered, and the disadvantage of higher resistivity becomes less important when high-frequency effects are considered.

The recovery of metal scrap for recycling contributes to the conservation of natural resources and the construction of a sound material cycle. A dynamic material (substance) flow analysis is useful to understand how and in what proportion materials are used, how they may dissipate into the environment, and how they partition into certain reservoirs (e.g. landfills). So, it enables us to investigate the potentials of metal scrap recovery in the designated area in the future. In this article a dynamic material flow analysis for copper and its alloys in Japan was conducted in order to estimate the stock, the amount of discarded and collected scraps in the future. There was a significant gap between the supply and the demand of scraps in statistics in Japan. The comparison between the estimation and the statistics suggested that this gap was due to the obsolete scraps which were not accounted as a supply of collected scraps. The amounts of collected copper scraps and its alloy scraps were estimated separately from 1970-2005. The results showed that approximately 300 thousand tons of high-purity copper or high copper alloys were recovered with impurities or copper-alloy scraps, which were finally consumed as copper-alloy scraps.

RESUMO Neste trabalho apresenta-se um estudo numérico-experimental do comportamento da agitação de fluido em reservatórios de pulverizadores agrícolas. Uma adequada agitação da calda de defensivos agrícolas em um reservatório é muito importante para garantir a homogeneidade da pulverização ao longo de toda a cultura. O objetivo do estudo foi avaliar a viabilidade da utilização de um modelo computacional aplicado ao problema de agitação de calda em reservatórios de pulverizadores agrícolas, e assim, auxiliar no projeto dos mesmos, com economia de tempo e custo. Deste modo, resultados de simulações computacionais de fluidodinâmica (CFD) foram comparados a testes experimentais normalizados. Utilizando um modelo monofásico (água), avaliaram-se os perfis de velocidades e de tensões de cisalhamento na parede do reservatório, a fim de possibilitar a visualização do comportamento do fluido em agitação e relacionar essas variáveis com a concentração de resíduos. A comparação entre resultados experimentais e o modelo computacional desenvolvido mostrou-se viável, indicando que regiões com baixos valores numéricos de tensão de cisalhamento estavam em concordância com as regiões de alta deposição de cobre da solução-teste. ABSTRACT This paper presents a numerical and experimental study of spray fluid performance with stirring in tanks of agricultural sprayers. The pesticide spray should be stirred properly to ensure spraying homogeneity throughout the entire crop. The aim of this study was to evaluate the feasibility of using computer models in pesticide spray stirring and, thus, reducing operational time and costs. Therefore, results of computer simulations of fluid dynamics (CFD) were compared to standard experimental tests. We evaluated shear stress and speed profiles against tank wall using a monophasic model (water). Thus, we could verify the fluid performance during stirring, and relate these variables with residue concentrations. The comparison between experimental and computational model was feasible since areas with lower numerical values of shear stress were in line with areas with high copper deposition.

The present work evaluates the reagents and appropriate conditions in order to obtain flotation concentrates with high copper content and low arsenic recovery. The studied ore is a blend of 80 % w/w El Valle ore and 20 % w/w Carlés ore, this latter being rich in copper and arsenic content. Those ores are worked from two deposits located in Asturias-Spain and treated at a concentration plant nearby. The arsenic content in the floated concentrate is penalized by the buyer. The main conclusion from the study is that a dithiophosphate is the collector that provides the best results, what was confirmed at plant-scale.El objetivo del presente trabajo es definir los reactivos y las condiciones apropiadas para obtener concentrados con alta ley de cobre y baja recuperación de arsénico, a partir de muestras de una mezcla con 80 % en peso de una mena de oro, cobre y bismuto, y 20 % en peso de otra mena rica en oro y cobre, pero con alta ley de arsénico, provenientes de los yacimientos El Valle y Carlés, ubicados en Asturias-España, y procesados en una planta de concentración. La presencia de arsénico en el concentrado flotado es penalizada por sus compradores. La principal conclusión del trabajo es que un ditiofosfato como único reactivo colector es el que logra alcanzar el objetivo planteado, lo que se comprobó con pruebas en la planta de concentración.

The main purposes of this research are to establish the extent and character of copper spray use in the viticulture industry in New Zealand; and to determine the level of copper accumulation nationally and in the main viticultural regions. The research also included pilot investigations of the storage of copper on different soil fractions and changes in nutrient status of vineyard soils with high copper concentrations. A questionnaire survey was completed by 124 growers from throughout the country. Copper sprays are still used in the majority of cases, but have either never been used or are no longer used in almost 30% of vineyards covered in the survey. Where copper is used, the load being applied to the vines each year varies widely, but the impression is that most growers are moderate in their use of copper. There are geographical patterns in use, and there is some evidence that newer vineyards, often in drier areas, are applying lower rates of copper, and less frequently. The maximum soil copper conce...

Introduction: Chromhidrosis is a rare sweat gland disorder charac­terized by the excretion of colored sweat. It can be classified as apocrine, true eccrine, and pseudochromhidrosis. Amongst the different types of chromhidrosis, green chromhidrosis is extremely rare. We describe herein a case of blue green chromhidrosis induced by ingestion of homeopathic medicine. Case report: A middle aged man presented to us with blue green discoloration of hands and feet. There was a preceding history of ingestion of homeopathic medication. Histopathology from the involved skin showed greenish particles within eccrine glands. Initial blood copper level was high which returned to normal level after discontinuation of the homeopathic medicine. Spectrophotometry revealed high copper content of the green sweat. Conclusion: Our case emphasizes the importance of considering any type of ingested medicine, including homeopathic medicine, as a probable cause of chromhidrosis.

Characteristics and mechanisms of PCDD/F formation with different feed materials in secondary copper smelting industry are investigated. The results indicate that PCDD/Fs are significantly formed even with the reaction time less than 0.1s, especially when the material containing high residues (Cu3) is fed. High copper content (65±2%) in the feed material enhances PCDD/F formation rate. Memory effect and de novo synthesis are two important mechanisms leading to PCDD/F formation. PCDD/F concentrations at the cyclone's inlet are between 2.92 and 12.4ng-TEQNm(-3) and increase with increasing residue content in the feed material. Two regions are identified for high potential of PCDD/F formation including the brass melt surface of the induction furnace and piping before the induced draft fan of the inlet hood. PCDD/Fs in flue gas are effectively removed with a cyclone and bag filter at low operating temperatures (60°C) to meet the emission limit of 1.0ng-TEQNm(-3). 1,2,3,4,6,7,8-HpCDF has the largest mass fraction of PCDD/Fs and can serve as a fingerprint for emissions from secondary copper smelting processes. The total emission factor of PCDD/Fs from flue gas, residual and fly ash in the secondary copper smelting process investigated is 22.01μg-TEQtonne(-1).

O cobre, em níveis supranutricionais nas dietas de frangos de corte, atua como promotor do crescimento. Para avaliar as respostas no desempenho e no colesterol sérico e muscular de frangos de corte, 1200 pintos (600 machos e 600 fêmeas) receberam rações suplementadas com 50, 100 ou 150 mg kg-1 de cobre como citrato cúprico, ou 200 mg kg-1 de cobre como sulfato cúprico pentahidratado, ou uma dieta controle, não suplementada, em um experimento em blocos casualizados com três repetições e arranjo fatorial de cinco tratamentos e dois sexos. As rações, baseadas em milho e farelo de soja e adequadas em todos os nutrientes (12 mg kg-1 de cobre na dieta controle), e água foram fornecidas à vontade durante o experimento de 42 dias. Não houve efeito (P>0,05) de tratamentos nas variáveis ganho de peso, consumo de ração (CR), conversão alimentar (CA) e mortalidade + refugagem (M+R) nos períodos de 1 a 21 dias e de 22 a 42 dias, com valores médios de 0,778 e 1,501 kg para GP, 1,181 e 3,087 kg para CR, 1,540 e 2,060 para CA, 1,42 e 2,08 % para M+R, respectivamente. Ao final do experimento o peso vivo (2,310 kg), o ganho de peso diário (55 g), o fator de produção (282,2), o colesterol no soro sangüíneo (129 mgdL-1) e o colesterol no músculo (55,9 mg 100 mL-1) também não foram afetados pelos tatamentos (P>0,05). Os machos e as fêmeas tiveram níveis semelhantes de colesterol (P>0,05) no soro e no músculo.

PrP(C), the normal isoform of the prion component PrP(Sc), is a 33-35-kDa glycophosphatidylinositol-anchored glycoprotein expressed in the plasma membrane of many cells and especially in the brain. The specific role of PrP(C) is unknown, although lately it has been shown to bind copper specifically. We show here that PrP(C) is present even in mature sperm cells, a polarized cell that retains only the minimal components required for DNA delivery, movement, and energy production. As opposed to PrP(C) in other cells, PrP in ejaculated sperm cells was truncated in its C terminus in the vicinity of residue 200. Sperm PrP, although membrane-bound, was not released by phosphatidylinositol phospholipase C as well as not localized in cholesterol-rich microdomains (rafts). Although no infertility was reported for PrP-ablated mice in normal situations, our results suggest that sperm cells originating from PrP-ablated mice were significantly more susceptible to high copper concentrations than sperm from wild type mice, allocating a protective role for PrP in specific stress situations related to copper toxicity. Since the functions performed by proteins in sperm cells are limited, these cells may constitute an ideal system to elucidate the function of PrP(C).

Background: Oral Squamous cell carcinoma (OSCC) is often preceded by potentially malignant disorders (PMDs) like oral submucous fibrosis (OSMF). The rate of transformation of OSMF to OSCC ranges from 3 to 19%. OSMF is etiologically related to chewing of areca nut (betel nut), a habit prevalent among the population groups in south-east Asia. Along with alkaloids, the high copper content in areca nut plays an important role in the pathogenesis of OSMF. The increased prevalence of OSMF in the last two decades or so corresponds with the increased processing and commercialization of areca nut products. Aim: The aim of the study was to estimate and compare the copper content of raw areca nuts in three different stages of maturity, and commercial areca nut products. Materials and Methods: Raw areca nut samples of three different maturities were obtained from four plantations in Sullia, Karnataka, India and commercial areca nut products were obtained from local shops in Chidambaram, Tamil Nadu, India. The samples were grounded and subjected to Atomic Absorption Spectrometry (AAS) for copper analysis. Results: There was statistically significant difference in copper content in raw areca nuts of all three maturities (p