Displaying publications 281 - 300 of 388 in total

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  1. Fulltext Nanoparticles in Construction Materials and Other Applications, and Implications of Nanoparticle Use
    Mohajerani A, Burnett L, Smith JV, Kurmus H, Milas J, Arulrajah A, et al.
    Materials (Basel), 2019 Sep 20;12(19).
    PMID: 31547011 DOI: 10.3390/ma12193052
    Nanoparticles are defined as ultrafine particles sized between 1 and 100 nanometres in diameter. In recent decades, there has been wide scientific research on the various uses of nanoparticles in construction, electronics, manufacturing, cosmetics, and medicine. The advantages of using nanoparticles in construction are immense, promising extraordinary physical and chemical properties for modified construction materials. Among the many different types of nanoparticles, titanium dioxide, carbon nanotubes, silica, copper, clay, and aluminium oxide are the most widely used nanoparticles in the construction sector. The promise of nanoparticles as observed in construction is reflected in other adoptive industries, driving the growth in demand and production quantity at an exorbitant rate. The objective of this study was to analyse the use of nanoparticles within the construction industry to exemplify the benefits of nanoparticle applications and to address the short-term and long-term effects of nanoparticles on the environment and human health within the microcosm of industry so that the findings may be generalised. The benefits of nanoparticle utilisation are demonstrated through specific applications in common materials, particularly in normal concrete, asphalt concrete, bricks, timber, and steel. In addition, the paper addresses the potential benefits and safety barriers for using nanomaterials, with consideration given to key areas of knowledge associated with exposure to nanoparticles that may have implications for health and environmental safety. The field of nanotechnology is considered rather young compared to established industries, thus limiting the time for research and risk analysis. Nevertheless, it is pertinent that research and regulation precede the widespread adoption of potentially harmful particles to mitigate undue risk.
    Matched MeSH terms: Copper
  2. Thermo-catalytic decomposition of polystyrene waste: Comparative analysis using different kinetic models
    Ali G, Nisar J, Iqbal M, Shah A, Abbas M, Shah MR, et al.
    Waste Manag Res, 2019 Aug 13.
    PMID: 31405341 DOI: 10.1177/0734242X19865339
    Due to a huge increase in polymer production, a tremendous increase in municipal solid waste is observed. Every year the existing landfills for disposal of waste polymers decrease and the effective recycling techniques for waste polymers are getting more and more important. In this work pyrolysis of waste polystyrene was performed in the presence of a laboratory synthesized copper oxide. The samples were pyrolyzed at different heating rates that is, 5°Cmin-1, 10°Cmin-1, 15°Cmin-1 and 20°Cmin-1 in a thermogravimetric analyzer in inert atmosphere using nitrogen. Thermogravimetric data were interpreted using various model fitting (Coats-Redfern) and model free methods (Ozawa-Flynn-Wall, Kissinger-Akahira-Sunose and Friedman). Thermodynamic parameters for the reaction were also determined. The activation energy calculated applying Coats-Redfern, Ozawa-Flynn-Wall, Kissinger-Akahira-Sunose and Friedman models were found in the ranges 105-148.48 kJmol-1, 99.41-140.52 kJmol-1, 103.67-149.15 kJmol-1 and 99.93-141.25 kJmol-1, respectively. The lowest activation energy for polystyrene degradation in the presence of copper oxide indicates the suitability of catalyst for the decomposition reaction to take place at lower temperature. Moreover, the obtained kinetics and thermodynamic parameters would be very helpful in determining the reaction mechanism of the solid waste in a real system.
    Matched MeSH terms: Copper
  3. Fulltext Differentiation of ripe and unripe fruit flour using mineral composition data-Statistical assessment
    Alkarkhi AFM, Alqaraghuli WAA, Mohamed Zam NR, Manan DMA, Mahmud MN, Huda N
    Data Brief, 2020 Jun;30:105414.
    PMID: 32258278 DOI: 10.1016/j.dib.2020.105414
    Data on the mineral composition and content of one heavy metal measured in three different fruit flours prepared from ripe and unripe fruits (pulp and peel) are presented. The mineral composition (sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), zinc (Zn), copper (Cu), iron (Fe) and manganese (Mn)) and content of one heavy metal (lead (Pb)) of the flours were analyzed by atomic absorption spectrophotometry. The analysis showed that the data can be used for differentiation between different fruits and stages of ripeness, as revealed by discriminant analysis and cluster analysis. The data provided can be used by researchers and scientists in the differentiation of fruits based on major and minor mineral elements.
    Matched MeSH terms: Copper
  4. Comparative study of raw and cooked farmed sea bass (Lates calcarifer) in relation to metal content and its estimated human health risk
    Tengku Nur Alia TKA, Hing LS, Sim SF, Pradit S, Ahmad A, Ong MC
    Mar Pollut Bull, 2020 Apr;153:111009.
    PMID: 32275555 DOI: 10.1016/j.marpolbul.2020.111009
    Metallic contamination in seafood, especially fish, has been of increasing concern to human health. Moreover, with increasing dependency on farmed fish for fish resources, the metallic contamination in them is still questionable. This study aimed to investigate the effects of cooking (steaming) on heavy metal concentration in farmed fish and to estimate its potential human health risk. Farmed sea basses (Lates calcarifer) from Setiu Lagoon were used to study the difference in metal uptake through human consumption of raw and cooked (steamed) fish samples. Selected heavy metals, namely copper (Cu), zinc (Zn), arsenic (As), cadmium (Cd), mercury (Hg) and lead (Pb), were measured using ICP-MS following Teflon bomb closed digestion of the fish samples. Cooking of the fish muscle by steaming was applied to investigate if cooking changes the concentration of heavy metals. Mercury and As were found accumulated more notably in the fish muscle, though only Hg was found to show significant (p > 0.05) increase when L. calcarifer is cooked. The amount of As in the fish muscle throughout its growth can be potentially harmful to humans, with the highest averaged concentration at 3.29 ± 0.65 mg/kg dw. above the standard set by the Malaysian Food Regulation (1985) of >1 mg/kg. All the other heavy metals were at relatively safe concentrations well below the standard set by both national and international guidelines. The PTWI per individual of L. calcarifer for As was at 0.84 mg/kg bw., which indicated that the amount of this fish safe for consumption without any adverse effect is 170 g/week. Therefore, long-term intake of these fish may pose a risk to human health due to the relatively higher Hg and As concentration found in these fishes.
    Matched MeSH terms: Copper
  5. Fulltext Dataset on leaching properties of coal ashes from Malaysian coal power plant
    Beddu S, Abd Manan TSB, Zainoodin MM, Khan T, Wan Mohtar WHM, Nurika O, et al.
    Data Brief, 2020 Aug;31:105843.
    PMID: 32596432 DOI: 10.1016/j.dib.2020.105843
    Coal combustion by-products (CCPs) (i.e. fly (FA) and bottom (BA) ashes) generated by power plants contain heavy metals. This research presents leaching properties of coal ashes (FA and BA) collected from Jimah coal-fired power station, Port Dickson, Negeri Sembilan using USEPA standard methods namely toxicity characteristic leaching procedure (TCLP), and synthetic precipitation leaching procedure (SPLP). Heavy metals like lead (Pb), zinc (Zn), copper (Cu) and arsenic (As) were quantified using atomic absorption spectrometer (AAS). The leached of heavy metals fluxes were Cu < Zn < Pb < As. As leached the most whilst indicating of possible contamination from As. Overall, the ranges of leached concentration were adhered to permissible limits of hazardous waste criteria for metal (Pb and As) and industrial effluent (Zn and Cu). The presented data has potential reuse as reference for the coal ash concrete mixed design application in construction industries.
    Matched MeSH terms: Copper
  6. Adsorption of Cu(II) and Ni(II) ions from wastewater onto bentonite and bentonite/GO composite
    Chang YS, Au PI, Mubarak NM, Khalid M, Jagadish P, Walvekar R, et al.
    Environ Sci Pollut Res Int, 2020 Sep;27(26):33270-33296.
    PMID: 32529626 DOI: 10.1007/s11356-020-09423-7
    Two superior adsorbents, namely bentonite and graphene oxide (GO), were hybridised to study the removal of copper and nickel ions from synthetic and industrial wastewater. The as-synthesised GO, bentonite/GO and bentonite were characterised by Fourier transform infrared spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy and N2 adsorption-desorption analysis. The factors influencing the adsorption behaviours including contact time, initial solution pH, ionic strength, initial concentration of metal ions, temperature and adsorbent dosage were systematically investigated by batch equilibrium method. The adsorption equilibrium for copper and nickel onto bentonite was attained in 90 min while equilibrium was reached in 60 min on bentonite/GO. The adsorption of copper and nickel was pH-dependent in the range from pH 2 to pH 7 and from pH 2 to pH 8. Pseudo-first-order kinetic model excellently described the adsorption of copper and nickel onto bentonite and bentonite/GO. The equilibrium adsorption data was well described by the Langmuir isotherm model and the maximum adsorption capacity was 248.9 mg/g, 558.4 mg/g, 215.8 mg/g and 402.5 mg/g for bentonite-copper, bentonite/GO-copper, bentonite-nickel and bentonite/GO-nickel adsorption systems, respectively. The bentonite/GO composite exhibited a higher adsorption capacity of both cations from synthetic wastewater than pure bentonite owning to the synergistic effect between bentonite and GO. In all adsorption studies, copper was more efficiently removed than nickel due to its higher tendency to form bond with adsorbent surfaces. The adsorption of copper and nickel on bentonite/GO was mainly due to cation exchange, intermolecular and electrostatic interactions and physisorption dominated the adsorption processes. The practical application of bentonite/GO on adsorption of copper was investigated using real wastewater and its removal efficiency was beyond 98%. The excellent adsorption performances of composites for the copper and nickel removal from wastewater demonstrated its significant potential for pollution mitigations.
    Matched MeSH terms: Copper
  7. Fulltext Synthesis, characterization and biological properties of copper(II) and zinc(II) complexes against blood-stage Plasmodium falciparum
    Lai, Jing-Wei, Ng, Chew-Hee, Lim, Yvonne Ai-Lian, Mohd Jamil Maah
    Malaysian Journal of Medicine and Health Sciences, 2019;15(102):1-1.
    MyJurnal
    Introduction: The spread of multidrug-resistant malaria parasite – Plasmodium sp. to commercially available antimalarial drugs, i.e. artemisinin-based combination therapies (ACTs) and chloroquine (CQ), has become a global treat to eliminate malaria. To limit the impact of antimalarial drug resistance, a new potent and affordable alternative is urgently needed. A number of metal-based compounds (metallodrugs) have been found active against Plasmodium falciparum, the species that causes potentially fatal cerebral malaria, as they are ease in ligand grafting of multi-functional groups. Ferroquine (FQ) is one of the metalloantimalarial drugs that is currently undergoing clinical trials. Methods: In this study, a series of ternary copper(II) and zinc(II) complexes – Cu(phen)(edda) 1, Zn(phen)(edda) 2, [Cu(phen)(cdmg)] NO3 3 and [Zn(phen)(c-dmg)]NO3 4 were synthesized and characterized by the following tests: Fourier transformed infrared (FTIR), CHN elemental analysis, UV-Vis spectroscopy, molar conductivity and magnetic susceptibility measurements. Results: In vitro hemolytic and antimalarial assays using SYBR Green I dye were done to determine the biological properties of these complexes. Preliminary biological evaluation demonstrated that all the complexes 1, 2, 3 and 4 exhibit toxicity against the sensitive blood-stage Plasmodium falciparum 3D7 with IC50 in μM range. Conclusion: Thus, metal complex is a potentially viable candidate as antimalarial drug to overcome the emergence of drug resistance.
    Matched MeSH terms: Copper
  8. Metal-Organic Framework Decorated Cuprous Oxide Nanowires for Long-lived Charges Applied in Selective Photocatalytic CO2 Reduction to CH4
    Wu H, Kong XY, Wen X, Chai SP, Lovell EC, Tang J, et al.
    Angew Chem Int Ed Engl, 2021 Apr 06;60(15):8455-8459.
    PMID: 33368920 DOI: 10.1002/anie.202015735
    Improving the stability of cuprous oxide (Cu2 O) is imperative to its practical applications in artificial photosynthesis. In this work, Cu2 O nanowires are encapsulated by metal-organic frameworks (MOFs) of Cu3 (BTC)2 (BTC=1,3,5-benzene tricarboxylate) using a surfactant-free method. Such MOFs not only suppress the water vapor-induced corrosion of Cu2 O but also facilitate charge separation and CO2 uptake, thus resulting in a nanocomposite representing 1.9 times improved activity and stability for selective photocatalytic CO2 reduction into CH4 under mild reaction conditions. Furthermore, direct transfer of photogenerated electrons from the conduction band of Cu2 O to the LUMO level of non-excited Cu3 (BTC)2 has been evidenced by time-resolved photoluminescence. This work proposes an effective strategy for CO2 conversion by a synergy of charge separation and CO2 adsorption, leading to the enhanced photocatalytic reaction when MOFs are integrated with metal oxide photocatalyst.
    Matched MeSH terms: Copper
  9. Fulltext Nutrient content in selected commercial rice in Malaysia: An update of Malaysian food composition database
    Mohd Fairulnizal, M.N., Norhayati, M.K., Zaiton, A., Norliza, A.H., Rusidah, S., Aswir, A.R., et al.
    International Food Research Journal, 2015;22(2):768-776.
    MyJurnal
    There is an increase need and demand to update Malaysian Food Composition Database (FCD) which was last updated in 1997. The current FCD program was designed to expand the quantity and improve the quality of the existing database. The present work was aimed to determine the nutrient content of commercial rice products from three rice varieties classified as raw and processed foods, namely Basmati, Siam, and Fragrant rice. A total of six brands from each type of rice were sampled from a local supermarket within Klang Valley. Analyses were carried out for 27 nutrients that include proximate (Energy, Water, Protein, Fat, Carbohydrate, Total Dietary Fibre, and Ash), minerals (Magnesium, Calcium, Sodium, Iron, Zinc, and Copper), water soluble vitamins (C, B1, B2, B3, B6 and B9), fat soluble vitamins (A and E), total sugar, fatty acids (total saturated fat, total monounsaturated fat and total polyunsaturated), trans fatty acids, and cholesterol. The three rice varieties were found to contain comparable nutrient levels except for vitamin C, B1, A, E and total sugar which were not detected in all samples. The fatty acid (total saturated, total monounsaturated, and total polyunsaturated) as well as trans- fatty acid were detected at very low levels. Cholesterol was not detected in all samples. These findings can be utilised in raising public awareness and assistance to better estimate nutrient contents and intake depending on the varieties of rice.
    Matched MeSH terms: Copper
  10. Control of Basal Stem Rot Disease in Oil Palm by Supplementation of Calcium, Copper, and Salicylic Acid
    Bivi MS, Paiko AS, Khairulmazmi A, Akhtar MS, Idris AS
    Plant Pathol J, 2016 Oct;32(5):396-406.
    PMID: 27721689
    Continuous supplementation of mineral nutrients and salicylic acid (SA) as foliar application could improve efficacy in controlling basal stem rot (BSR) disease in oil palm seedling. It is revealed from the results that the highest disease severity index (58.3%) was recorded in T8 treatments at 9 months after inoculation. The best disease control was achieved by T7 treatments (calcium/copper/SA [Ca/Cu/SA]) (5.0%) followed by T1 (5.5%), T5 (5.8%), T3 (8.3%), T6 (8.3%), T4 (13.3%), and T2 (15.8%) treatments. Continuous supplementation of Ca/Cu/SA was found to be the most effective in controlling the disease and the high performance liquid chromatography results showed the detection of ergosterol at very low concentration in the treated samples. Moreover, the transmission electron microscopy analysis results clearly indicated that T7 treatment was also enhancing lignification, which was responsible for the thickness of the secondary cell walls and middle lamella compared to untreated samples. It was therefore, concluded that continuous supplementation of minerals nutrients and SA could effectively suppress disease severity by reducing ergosterol activity and also improve the process of lignification in the treated plants. Furthermore, this treatment also managed to delay the onset of BSR symptoms and promote the growth of the seedlings and eventually suppress the BSR disease.
    Matched MeSH terms: Copper
  11. Determination of silver, bismuth, cadmium, copper, iron, nickel and zinc in lead- and tin-base solders and white-metal bearing alloys by atomic-absorption spectrophotometry
    Chong C
    Talanta, 1986 Jan;33(1):91-4.
    PMID: 18964038
    A simple atomic-absorption spectrophotometry method is described for the determination of silver, bismuth, cadmium, copper, iron, nickel and zinc in lead- and tin-base solders and white-metal bearing alloys, with use of a single sample solution. The sample is dissolved in a mixture of hydrobromic acid and bromine, then fumed with sulphuric acid. The lead sulphate is dissolved in concentrated hydrochloric acid. The method is particularly suitable for the determination of silver and bismuth, which are co-precipitated with lead sulphate. The other elements can also be determined after removal of the lead sulphate by filtration.
    Matched MeSH terms: Copper
  12. Fulltext Evaluation of closed vessel microwave digestion of fish muscle with various solvent combinations using fractional factorial design
    Low, K.H., Zain, S.M., Abas, M.R., Ali Mohd, M.
    ASM Science Journal, 2009;3(1):71-76.
    MyJurnal
    Fractional factorial design was utilized to evaluate the effect of combinations of nitric acid, hydrogen peroxide, hydrochloric acid and water for microwave digestion of fish muscle. Upon digestion, copper, iron and zinc were determined by flame atomic absorption spectroscopy. H2O2 and HCl volumes were found to be the most significant parameters which resulted in good metal recoveries. This is especially so for the effect of HCl on Fe recovery. The results indicated that the combination of 4 mL 65% HNO3, 2 mL 30% H2O2 and 2 mL 30% HCl gave the most satisfactory percentage recovery. There was good agreement between measured and certified values for all metals with respect to the DORM-3 fish protein.
    Matched MeSH terms: Copper
  13. Fulltext Nutritional composition of ready-to-eat cereals in the Malaysian market
    Suraiami, M., Mohd Fairulnizal, M.N., Norhayati, M.K., Zaiton, A., Norliza, A.H., Wan Syuriahti, W.Z., et al.
    Malays J Nutr, 2014;20(3):417-427.
    MyJurnal
    Introduction: This study aimed to determine the nutrient content of cornflakes and muesli, ready-to-eat cereal products available in the Malaysian market. Cornflakes and muesli were chosen due to their popularity as a breakfast meal especially in urban areas. Methods: A total of six brands each for cornflakes and muesli were purchased from supermarkets in the Klang Valley using stratified random sampling. All samples were analysed using AOAC official methods of analysis. The validity of the test data was monitored with the application of internal quality controls in line with the requirements of ISO 17025. Results: Proximate analysis revealed significantly higher mean levels of carbohydrate (86.94 ± 0.59 mg/lOOg), minerals such as iron (8.48±1.72 mg/lOOg) and sodium (674.83±102.99 g/lOOg), B3 as niacinamide (25.87 ± 6.14 g/lOOg) and sucrose (5.10 ± 0.90 mg/lOOg) in cornflakes than in muesli. However, muesli contained significantly more mean moisture (10.23 ± 0.72 mg/lOOg), protein (10.07 ± 0.79 mg/lOOg), total dietary fibre (12.49 ± 1.44 mg/lOOg), magnesium (113.22 ± 7.93 mg/lOOg), zinc (1.65 ± 0.16 mg/lOOg), copper (0.25 ± 0.02 mg/lOOg), total sugar (18.75 ± 2.05 mg/lOOg), glucose (7.70±1.77 mg/lOOg) and fructose (8.68±1.76 mg/lOOg) than cornflakes. Most of the fatty acids analysed were not detected or of low value in both the cereal products. Conclusion: The nutrient analysis of cornflakes and muesli suggests that both ready-to-eat cereals are nutritionally good choice as breakfast for consumers as it provides carbohydrate, minerals, fibre and vitamins. The data provides additional information to the Malaysian Food Composition Database.
    Matched MeSH terms: Copper
  14. Fulltext Removal of copper from aqueous solution by adsorption using magnesium aluminium hydrogenphosphate layered double hydroxides
    Zaini Hamzah, Mohd Najif Ab Rahman, Siti Mariam Sumari, Yamin Yasin, Ahmad Saat
    Journal of Nuclear and Related Technologies, 2011;2011(2):60-67.
    MyJurnal
    Layered double hydroxide (LDH) with Mg/Al molar ratio of 4/1 (MAN-4) was synthesized by co-precipitation and followed by hydrothermal method. The compound was allowed to undergo ion exchange with K2HPO4 for 48 hours to produce MgAlHPO4 (MAHP-4). The solid produced was characterized using X-ray diffraction (XRD) and Fourier Transform Infrared spectroscopy (FTIR). Adsorption of copper solution by MAHP-4 was carried out using batch experiment by mixing the copper solution and the sorbent MAHP-4. The effects of
    various parameters such as contact time, pH, adsorbent dosage and initial concentration were investigated. The optimum pH for copper removal was found to be 4 and the optimum time of copper removal was found at 4 hours. The isotherm data was analysed using model isotherm Langmuir with the correlation coefficient of 0.999 was recorded. The maximum adsorption capacity, Qo (mg/g) of 142.8 mg/g was also recorded from the Langmuir isotherm. The remaining copper solution was determined by using EDXRF (Energy Dispersive XRay Fluorescence spectrometry) model MiniPal 4 (PAN analytical). The results in this study indicate that MAHP-4 has potential as an effective adsorbent for removing copper from aqueous solution.
    Matched MeSH terms: Copper
  15. Fulltext Physical, chemical & mineralogical properties of fly ash
    Khairul Nizar Ismail, Kamarudin Hussin, Mohd Sobri Idris
    Journal of Nuclear and Related Technologies, 2007;2005(1):47-51.
    MyJurnal
    Fly ash is the finely divided mineral residue resulting from the combustion of coal in electric generating plants. Fly ash consists of inorganic, incombustible matter present in the coal that has been fused during combustion into a glassy, amorphous structure. Fly ash particles are generally spherical in shape and range in size from 2 μm to 10 μm. They consist mostly of silicon dioxide (SiO2), aluminium oxide (Al2O3) and iron oxide (Fe2O3). Fly ash like soil contains trace concentrations of the following heavy metals: nickel, vanadium, cadmium, barium, chromium, copper, molybdenum, zinc and lead. The chemical compositions of the sample have been examined and the fly ash are of ASTM C618 Class F.
    Matched MeSH terms: Copper
  16. Fulltext Phase formation study of CuAlO2 transparent conductive oxide thin films
    Hutagalung, Sabar D., Woon, Wu S., Khatijah A. Yaacob, Lockman, Zainovia
    Journal of Nuclear and Related Technologies, 2007;2007(1):165-170.
    MyJurnal
    P-type transparent conductive oxide of copper aluminum oxide (CuAlO2) thin films were prepared by using sol-gel method with nitrate solutions as starting precursor. Copper nitrate and aluminum nitrate were selected as raw materials that provide the copper and aluminum source. The CuAlO2 thin films were deposited on pre-cleaned silicon substrate by spin-coating technique. To study of phase formation of CuAlO2, as prepared sample was dried and subjected to heat treatment at various temperatures. The heat-treated samples were characterized by x-ray diffraction (XRD) and energy dispersive x-ray (EDX). From XRD analysis result found that CuAlO2 phase was formed after annealing at 1100 o C for 4 hrs. EDX result of annealed sample at 1100 o C shows composition of Cu and Al that indicate the possibility of forming CuAlO2.
    Matched MeSH terms: Copper
  17. Fulltext Evaluation of trace elements iron, zinc, copper and lead in the diet of female university students
    Malays J Nutr, 1995;1(1):-.
    MyJurnal
    Food consumption of 50 female students in Universiti Kebangsaan Malaysia was recorded for 7 days. Foods and drinks most frequently consumed were selected for analysis of iron, zinc, copper and lead content. The mean daily intakes of energy, protein, carbohydrate and fat among the students are 6.5±1.4 MJ (1550±335 kcal), 59.8±18.5g. 227. 1±54.6 g and 46.0±11.5 g respectively. This diet contributed 19.6±6.4 mg Fe, 7.0±2.0 mg Zn and 1.6±0.6 mg Cu per day which were lower than the Malaysian RDA for Fe and US RDA for Zn, while Cu is within the recommended range. The main sources of these minerals in the student’s diet were rice, rice products, meat and animal products. Lead concentration in the diet (134±77 ug/day) is below the acceptable daily intake (ADI) value suggested by Codex Alimentarius Commission (1984). This study indicated concern regarding the low intake of the essential trace elements on long term basis among the students.
    Matched MeSH terms: Copper
  18. Fulltext The status of heavy metals contamination in seafood and its products imported through the Bukit Kayu Hitam entry point
    Shafie, O., Sanimah, A.R.
    Malaysian Journal of Public Health Medicine, 2002;2(1):26-30.
    MyJurnal
    The status ofhve l1eavy metals: cadmium, lead copper, zinc and mercury were determined in seafood and its products imported_ti·om Thailand via Bukit Kayu Hiram, Kedah, Flame Atomic Absorption Spectrophotometer was used to determine the level of these heary metals except for mercury, where the cold vapor technique was used, Randomized sampling was done according to a predetermined sampling plan based on the previous years consignments. Data collected were compared with the maximum permitted level of -metal contaminants in fish and fish products- ofthe Fourteenth Schedule (Regulation 38) of Food Act I983 and Food Regulations I 985 to ascertain compliance. lt was noted form this study, that the level of metals detected in seafood and its products had a very wide range, The levels detected for cadmium was at a range of 0. 00] - 3.9/2, 0.07 — 0.29, 0,04 - 4,4 mg/kg in fish, shellfish and cuttlefish respectivelv. In general, cadmium level in some samples was notably higher particularly in shellfish. All samples had lead level less than the permitted value except for fish where the highest value detected was 3.28 mg/kg. The level of copper and zinc was higher than the permitted value in octopus, prawn and crab, Mercury level in all samples analvzed was found to be below the detection level. As for fish samples, zinc level was found to be higher whereas copper was within the limit. However, it was also noted that the level of all the heavy metals in jiozen jish was within the permitted limit.
    Matched MeSH terms: Copper
  19. Comprehensive genomic and phenotypic metal resistance profile of Pseudomonas putida strain S13.1.2 isolated from a vineyard soil
    Chong TM, Yin WF, Chen JW, Mondy S, Grandclément C, Faure D, et al.
    AMB Express, 2016 Dec;6(1):95.
    PMID: 27730570
    Trace metals are required in many cellular processes in bacteria but also induce toxic effects to cells when present in excess. As such, various forms of adaptive responses towards extracellular trace metal ions are essential for the survival and fitness of bacteria in their environment. A soil Pseudomonas putida, strain S13.1.2 has been isolated from French vineyard soil samples, and shown to confer resistance to copper ions. Further investigation revealed a high capacity to tolerate elevated concentrations of various heavy metals including nickel, cobalt, cadmium, zinc and arsenic. The complete genome analysis was conducted using single-molecule real-time (SMRT) sequencing and the genome consisted in a single chromosome at the size of 6.6 Mb. Presence of operons and gene clusters such as cop, cus, czc, nik, and asc systems were detected and accounted for the observed resistance phenotypes. The unique features in terms of specificity and arrangements of some genetic determinants were also highlighted in the study. Our findings has provided insights into the adaptation of this strain to accumulation and persistence of copper and other heavy metals in vineyard soil environment.
    Matched MeSH terms: Copper
  20. DNA Damage, Copper and Lead Associates with Cognitive Function among Older Adults
    Meramat A, Rajab NF, Shahar S, Sharif RA
    J Nutr Health Aging, 2017;21(5):539-545.
    PMID: 28448084 DOI: 10.1007/s12603-016-0759-1
    BACKGROUND: A cross sectional study was conducted in a group of 317 subjects older than 60 in Malaysia, aimed to determine risk factors associated with cognitive impairment in older adults, focusing on trace elements and DNA damage.

    METHOD: Cognitive decline was determined by Montreal Cognitive Assessment (MoCA). Oxidative stress markers (malondialdehyde-MDA and superoxide dismutase-SOD) were determined and DNA damage was assayed using Alkaline Comet Assay. Toenail samples were taken and analyzed using ICP-MS to determine trace element levels.

    RESULTS: A total of 62.1 % of subjects had cognitive impairment. Subjects with cognitive impairment had significantly higher levels of MDA and DNA damage as compared to the group with normal cognitive function; MDA (2.07 ± 0.05 nmol/L vs 1.85 ± 0.06 nmol/L) (p<0.05) and DNA damage (% Tail Density, 14.52 ± 0.32 vs 10.31 ± 0.42; Tail Moment, 1.79 ± 0.06 vs 1.28 ± 0.06) (p<0.05 for all parameters). However, the level of SOD among subjects with cognitive impairment (6.67 ± 0.33 u.e/min/mg protein) was lower than the level among those with normal cognitive functions (11.36 ± 0.65 u.e/min/mg protein) (p<0.05). Multiple logistic regression revealed the predictors for cognitive impairment among the subjects were DNA damage (Adjusted odd ratio [OR], 1.37; 95% confidence interval [CI], 1.18-1.59), level of trace elements in toenails namely, lead (OR, 2.471; CI, 1.535-3.980) and copper (OR, 1.275; CI, 1.047-1.552) (p<0.05).

    CONCLUSION: High levels of lead and copper can lead to increase in oxidative stress levels and are associated with DNA damage that eventually could be associated with cognitive decline.

    Matched MeSH terms: Copper/administration & dosage; Copper/adverse effects*; Copper/metabolism
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