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Fulltext Accumulation and risk assessment of heavy metals employing species sensitivity distributions in Linggi River, Negeri Sembilan, Malaysia

Razak MR, Aris AZ, Zakaria NAC, Wee SY, Ismail NAH

Ecotoxicol Environ Saf, 2021 Mar 15;211:111905.
PMID: 33453636 DOI: 10.1016/j.ecoenv.2021.111905

The constant increase of heavy metals into the aqueous environment has become a contemporary global issue of concern to government authorities and the public. The study assesses the concentration, distribution, and risk assessment of heavy metals in freshwater from the Linggi River, Negeri Sembilan, Malaysia. Species sensitivity distribution (SSD) was utilised to calculate the cumulative probability distribution of toxicity from heavy metals. The aquatic organism's toxicity data obtained from the ECOTOXicology knowledgebase (ECOTOX) was used to estimate the predictive non-effects concentration (PNEC). The decreasing sequence of hazardous concentration (HC5) was manganese > aluminium > copper > lead > arsenic > cadmium > nickel > zinc > selenium, respectively. The highest heavy metal concentration was iron with a mean value of 45.77 μg L-1, followed by manganese (14.41 μg L-1) and aluminium (11.72 μg L-1). The mean heavy metal pollution index (HPI) value in this study is 11.52, implying low-level heavy metal pollutions in Linggi River. The risk quotient (RQ) approaches were applied to assess the potential risk of heavy metals. The RQ shows a medium risk of aluminium (RQm = 0.1125) and zinc (RQm = 0.1262); a low risk of arsenic (RQm = 0.0122) and manganese (RQm = 0.0687); and a negligible risk of cadmium (RQm = 0.0085), copper (RQm = 0.0054), nickel (RQm = 0.0054), lead (RQm = 0.0016) and selenium (RQm = 0.0012). The output of this study produces comprehensive pollution risk, thus provides insights for the legislators regarding exposure management and mitigation.

Matched MeSH terms: Copper/analysis
Cadmium, copper, and zinc toxicity to the clam, Donax faba C., and the blood cockle, Anadara granosa L

Ong ES, Din ZB

Bull Environ Contam Toxicol, 2001 Jan;66(1):86-93.
PMID: 11080341
Matched MeSH terms: Copper/toxicity*
Removal of Cu and Pb by tartaric acid modified rice husk from aqueous solutions

Wong KK, Lee CK, Low KS, Haron MJ

Chemosphere, 2003 Jan;50(1):23-8.
PMID: 12656225

A study on the modification of rice husk by various carboxylic acids showed that tartaric acid modified rice husk (TARH) had the highest binding capacities for Cu and Pb. The carboxyl groups on the surface of the modified rice husk were primarily responsible for the sorption of metal ions. A series of batch experiments using TARH as the sorbent for the removal of Cu and Pb showed that the sorption process was pH dependent, rapid and exothermic. The sorption process conformed to the Langmuir isotherm with maximum sorption capacities of 29 and 108 mg/g at 27 +/- 2 degrees C for Cu and Pb, respectively. The uptake increased with agitation rate. Decrease in sorbent particle size led to an increase in the sorption of metal ions and this could be explained by an increase in surface area and hence binding sites. Metal uptake was reduced in the presence of competitive cations and chelators. The affinity of TARH for Pb is greater than Cu.

Matched MeSH terms: Copper/chemistry*
The concentration of selected minerals and phytate in Malaysian Brachiaria decumbens

Noordin MM, Zhang SS, Rahman SO, Haron J

Vet Hum Toxicol, 2000 Oct;42(5):276-9.
PMID: 11003117

Samples of Brachiaria decumbens collected from 5 farms representing the Peninsular Malaysia were subjected to selected trace mineral and phytate analyses to explain the pathogenesis of B decumbens intoxication. Concentrations of Cu, Zn, Fe and Mo were comparable to other grasses while that of phytate was low. The molar ratios of Cu:Zn, Cu:Mo, and Cu:Fe warrant that Cu deficiency is involved in the toxicity of B decumbens. This might aggravate the development of photosensitization of unpigmented or lightly pigmented areas of affected animals. The Zn:phytate ratio could predispose to Zn deficiency during intoxication.

Matched MeSH terms: Copper/analysis
Sediment trace metal concentrations from the mudflats of Kuala Juru and Kuala Muda of Malaysia

Mat I, Maah MJ

Bull Environ Contam Toxicol, 1994 Nov;53(5):740-6.
PMID: 7833611
Matched MeSH terms: Copper/analysis
Lead in blood and hair of population near an operational and a proposed area for copper mining, Malaysia

Mokhtar MB, Awaluddin AB, Fong CW, Woojdy WM

Bull Environ Contam Toxicol, 1994 Jan;52(1):149-54.
PMID: 8130410
Matched MeSH terms: Copper*
Copper vapour laser ID labelling on metal dentures and restorations

Ling BC, Nambiar P, Low KS, Lee CK

J Forensic Odontostomatol, 2003 Jun;21(1):17-22.
PMID: 12793127

Denture marking is accepted as a means of identifying dentures and persons in geriatric institutions, or post-mortem during war, crimes, civil unrest, natural and mass disasters. Labelling on the acrylic resin component of the denture can easily be damaged or destroyed by fire but on cobalt-chromium components it would be more resistant. A copper vapour laser (CVL) can be used to label the cobalt-chromium components of dentures and metal restorations easily, and legibly, and miniaturised for the incorporation of more personal particulars necessary for the identification of the deceased person. The CVL beam is focussed by its optics and delivered to the material surface by the two-axis scanner mounted with mirrors. A personal computer controls the movement of the scanner and the firing of the CVL. The high peak power of the pulsed CVL is focussed to very high energy density producing plasma ablation of the alloy surface. Very fine markings of a few microns width can be produced enabling the storage of detailed information of the deceased person on a metal surface for the purpose of rapid identification.

Matched MeSH terms: Copper/chemistry
The kinetics of bioaccumulation of zinc, copper, lead and cadmium by oysters (Crassostrea iredalei and C. belcheri) under tropical field conditions

Lim PE, Lee CK, Din Z

Sci Total Environ, 1998 May 14;216(1-2):147-57.
PMID: 9618930

A study on the kinetics of accumulation and depuration of Zn, Cu, Pb and Cd by the oysters (Crassostrea iredalei and Crassostrea belcheri) cultured at two locations in the Merbok Estuary, Malaysia was conducted. A first-order kinetic model was employed to fit the experimental data in order to estimate the rate constants for uptake and elimination processes and to predict the bioconcentration factors (BCF). Among the four metals studied, only the Zn accumulation process could not be modelled using first-order kinetics. The elimination rate constants estimated from depuration data for C. iredalei are found to be much greater than those from accumulation data. The results suggest that the values of kinetic parameters and BCFs derived under conditions of both aqueous and dietary exposure are probably more site- than species-specific.

Matched MeSH terms: Copper/pharmacokinetics
Effects of adsorbents and copper(II) on activated sludge microorganisms and sequencing batch reactor treatment process

Ong SA, Lim PE, Seng CE

J Hazard Mater, 2003 Oct 31;103(3):263-77.
PMID: 14573344

Wastewater treatment systems employing simultaneous adsorption and biodegradation processes have proven to be effective in treating toxic pollutants present in industrial wastewater. The objective of this study is to evaluate the effect of Cu(II) and the efficacy of the powdered activated carbon (PAC) and activated rice husk (ARH) in reducing the toxic effect of Cu(II) on the activated sludge microorganisms. The ARH was prepared by treatment with concentrated nitric acid for 15 h at 60-65 degrees C. The sequencing batch reactor (SBR) systems were operated with FILL, REACT, SETTLE, DRAW and IDLE modes in the ratio of 0.5:3.5:1:0.75:0.25 for a cycle time of 6 h. The Cu(II) and COD removal efficiency were 90 and 85%, respectively, in the SBR system containing 10 mg/l Cu(II) with the addition of 143 mg/l PAC or 1.0 g PAC per cycle. In the case of 715 mg/l ARH or 5.0 g ARH per cycle addition, the Cu(II) and COD removal efficiency were 85 and 92%, respectively. ARH can be used as an alternate adsorbent to PAC in the simultaneous adsorption and biodegradation wastewater treatment process for the removal of Cu(II). The specific oxygen uptake rate (SOUR) and kinetic studies show that the addition of PAC and ARH reduce the toxic effect of Cu(II) on the activated sludge microorganisms.

Matched MeSH terms: Copper/chemistry*
Fulltext An Artificial Neural Network Based Analysis of Factors Controlling Particle Size in a Virgin Coconut Oil-Based Nanoemulsion System Containing Copper Peptide

Samson S, Basri M, Fard Masoumi HR, Abdul Malek E, Abedi Karjiban R

PLoS One, 2016;11(7):e0157737.
PMID: 27383135 DOI: 10.1371/journal.pone.0157737

A predictive model of a virgin coconut oil (VCO) nanoemulsion system for the topical delivery of copper peptide (an anti-aging compound) was developed using an artificial neural network (ANN) to investigate the factors that influence particle size. Four independent variables including the amount of VCO, Tween 80: Pluronic F68 (T80:PF68), xanthan gum and water were the inputs whereas particle size was taken as the response for the trained network. Genetic algorithms (GA) were used to model the data which were divided into training sets, testing sets and validation sets. The model obtained indicated the high quality performance of the neural network and its capability to identify the critical composition factors for the VCO nanoemulsion. The main factor controlling the particle size was found out to be xanthan gum (28.56%) followed by T80:PF68 (26.9%), VCO (22.8%) and water (21.74%). The formulation containing copper peptide was then successfully prepared using optimum conditions and particle sizes of 120.7 nm were obtained. The final formulation exhibited a zeta potential lower than -25 mV and showed good physical stability towards centrifugation test, freeze-thaw cycle test and storage at temperature 25°C and 45°C.

Matched MeSH terms: Copper/chemistry*
Fulltext Uterine perforation by the intra-uterine device

Raman S, Sivanesaratnam V, Sinnathuray TA

Med J Malaysia, 1981 Sep;36(3):151-4.
PMID: 7199110
Matched MeSH terms: Intrauterine Devices, Copper/adverse effects
Effect of laparoscopic sterilization and insertion of Multiload Cu 250 and Progestasert IUDs on serum ferritin levels

Goh TH, Hariharan M

Contraception, 1983 Oct;28(4):329-36.
PMID: 6667621

Blood haemoglobin and serum ferritin levels were measured at the initial visit and 12 months following sterilization and IUD insertion. Ferritin levels were unaltered in Progestasert users after 12 months but haemoglobin values increased though not significantly. Ferritin levels fell in Multiload Cu 250 users and in sterilized women; haemoglobin levels were also observed to fall but significantly only in the latter group. Iron-deficiency anaemia was prevalent at initial contact and there appeared to be an increased risk subsequently in Multiload Cu 250 users and in those who were sterilized. Screening and monitoring for anaemia is indicated. From the viewpoint of iron status, the Progestasert is preferable to the Multiload Cu 250 but it suffers the major disadvantages of needing frequent replacement and of causing menstrual disturbances which might compromise its acceptability. Menstrual blood loss studies may help explain why anaemia develops after sterilization.

Matched MeSH terms: Intrauterine Devices, Copper*
Bacteriological study of extracted IUCDs

Harun R, Nayar S, Thum Yin Lai

Malays J Reprod Health, 1989 Dec;7(2):131-7.
PMID: 12283073

PIP: Previous studies have shown the users of intrauterine devices have a 4.4 times greater risk of pelvic inflammatory disease. This present study intends to categorize the distribution of microbes in cultures from different types of extracted copper intrauterine devices (IUCDs). Bacteriological studies of aerobic and anaerobic organisms were performed on the extracted IUCDs of 522 IUCD users; 480 wearing a Multiload Cu 250, 15 wearing a Copper T, 22 Lippes Loop and 5 a Copper 7. Cultures were negative in 46 (8.8%) IUCD cultures where 43 were Multiloads, Copper T (1) and Lippes Loop (2). 91.2% yielded bacterial growth and the commonest organisms isolated were Staphylococcus species, (23%), E.coli (9.6%) and Staphylococcus aureus (4.0%. Candida albicans, E.coli and Staphylococcus sp. were commonly isolated from Multiload, Copper T, Lippes Loop and Copper 7. Beta-hemolytic streptococci, Staphylococcus aureus and Candida sp. were frequently recovered from Multiload, Copper T and Lippes Loop. Only Multiload cultures yielded Bacillus, Streptococcus viridans, Klebsiella, Proteus, Enterobacter, Citrobacter diversus, Citrobacter freundii, Moraxella, Pseudomonas and Acinetobacter. One woman with complaint of PID yielded E.coli in her IUCD culture.

Matched MeSH terms: Intrauterine Devices, Copper*
Fulltext Circulating copper and zinc levels and risk of hepatobiliary cancers in Europeans

Stepien M, Hughes DJ, Hybsier S, Bamia C, Tjønneland A, Overvad K, et al.

Br J Cancer, 2017 Feb 28;116(5):688-696.
PMID: 28152549 DOI: 10.1038/bjc.2017.1

BACKGROUND: Copper and zinc are essential micronutrients and cofactors of many enzymatic reactions that may be involved in liver-cancer development. We aimed to assess pre-diagnostic circulating levels of copper, zinc and their ratio (Cu/Zn) in relation to hepatocellular carcinoma (HCC), intrahepatic bile duct (IHBD) and gall bladder and biliary tract (GBTC) cancers.
METHODS: A nested case-control study was conducted within the European Prospective Investigation into Cancer and Nutrition cohort. Serum zinc and copper levels were measured in baseline blood samples by total reflection X-ray fluorescence in cancer cases (HCC n=106, IHDB n=34, GBTC n=96) and their matched controls (1:1). The Cu/Zn ratio, an indicator of the balance between the micronutrients, was computed. Multivariable adjusted odds ratios and 95% confidence intervals (OR; 95% CI) were used to estimate cancer risk.
RESULTS: For HCC, the highest vs lowest tertile showed a strong inverse association for zinc (OR=0.36; 95% CI: 0.13-0.98, Ptrend=0.0123), but no association for copper (OR=1.06; 95% CI: 0.45-2.46, Ptrend=0.8878) in multivariable models. The calculated Cu/Zn ratio showed a positive association for HCC (OR=4.63; 95% CI: 1.41-15.27, Ptrend=0.0135). For IHBC and GBTC, no significant associations were observed.
CONCLUSIONS: Zinc may have a role in preventing liver-cancer development, but this finding requires further investigation in other settings.

Matched MeSH terms: Copper/blood*
Novel combination of zero-valent Cu and Ag nanoparticles @ cellulose acetate nanocomposite for the reduction of 4-nitro phenol

Khan FU, Asimullah, Khan SB, Kamal T, Asiri AM, Khan IU, et al.

Int J Biol Macromol, 2017 Sep;102:868-877.
PMID: 28428128 DOI: 10.1016/j.ijbiomac.2017.04.062

A very simple and low-cost procedure has been adopted to synthesize efficient copper (Cu), silver (Ag) and copper-silver (Cu-Ag) mixed nanoparticles on the surface of pure cellulose acetate (CA) and cellulose acetate-copper oxide nanocomposite (CA-CuO). All nanoparticles loaded onto CA and CA-CuO presented excellent catalytic ability, but Cu-Ag nanoparticles loaded onto CA-CuO (Cu0-Ag0/CA-CuO) exhibited outstanding catalytic efficiency to convert 4-nitrophenol (4-NP) into 4-aminophenol (4-AP) in the presence of NaBH4. Additionally, the Cu0-Ag0/CA-CuO can be easily recovered by removing the sheet from the reaction media, and can be recycled several times, maintaining high catalytic ability for four cycles.

Matched MeSH terms: Copper/chemistry*
Immunological parameters of Javanese carp Puntius gonionotus (Bleeker) exposed to copper and challenged with Aeromonas hydrophila

Shariff M, Jayawardena PA, Yusoff FM, Subasinghe R

Fish Shellfish Immunol, 2001 May;11(4):281-91.
PMID: 11417716

This study was to determine the median lethal concentration (LC50) of copper to Javenese carp, Puntius gonionotus (Bleeker), and the immune response after the fish were exposed to sublethal levels of copper and challenged with formalin killed Aeromonas hydrophila. The LC50 of copper on P. gonionotus at 24, 48, 72, 96 and 120 h were estimated as 2.17, 0.91, 0.57, 0.53 and 0.42 mg l(-1), respectively. To determine the effect of copper on the immune system, fish were exposed for 66 days to 0.05, 0.10 and 0.15 mg Cu l(-1). After 56 days of initial exposure to copper, fish were challenged with 0.1 ml of 4.5 x 10(5) cfu ml(-1) formalin killed A. hydrophila and maintained in the same concentration of copper. After the challenge, the immune response was monitored for 2 weeks using haematological and serological assays. During the initial phase of exposure to copper, significant changes were noted in the white blood cell, lysozyme, potential killing activity, total plasma protein, total immunoglobulin and haematocrit levels between the control and treated fish. One week after challenge with A. hydrophila, there was a significant increase in the values of white blood cells, total protein and total immunoglobulin compared to the values before the challenge. However, these values were not significantly different (P>0.05) between the control and the treated fish. In contrast, NBT and lysozyme assays exhibited a significant difference (P<0.05) in fish exposed to 0.10 mg Cu l(-1) (0.525 +/- 0.17; 24.42 +/- 3.35 x 10(2) micromg ml(-1)) and 0.15 mg Cu 1(-1) (0.536 +/- 0.19; 21.78 +/- 1.29 x 10(2) micromg ml(-1)) compared to the control (0.746 +/- 0.31; 30.73 +/- 5.42 x 10(2) micromg ml(-1)) after the bacterial challenge (day 61). There was however no significant difference (P>0.05) in NBT and lysozyme levels in fish exposed to lower level of copper (0.05 mg Cu l(-1)), suggesting the absence of immunosuppressive effects at lower level of exposure.

Matched MeSH terms: Copper/toxicity*
Simultaneous adsorption and biodegradation processes in sequencing batch reactor (SBR) for treating copper and cadmium-containing wastewater

Lim PE, Ong SA, Seng CE

Water Res, 2002 Feb;36(3):667-75.
PMID: 11827329

The application of simultaneous adsorption and biodegradation processes in the same reactor is known to be effective in the removal of both biodegradable and non-biodegradable contaminants in various kinds of wastewater. The objective of this study is to evaluate the efficacy of the two processes under sequencing batch reactor (SBR) operation in treating copper and cadmium-containing synthetic wastewater with powdered activated carbon (PAC) as the adsorbent. The SBR systems were operated with FILL, REACT, SETTLE, DRAW and IDLE periods in the ratio of 0.5: 3.5: 1.0: 0.75 :0.25 for a cycle time of 6 h. In the presence of 10 mg/L Cu(II) and 30 mg/L Cd(II), respectively, the average COD removal efficiencies were above 85% with the PAC dosage in the influent solution at 143 mg/L compared to around 60% without PAC addition. Copper(II) was found to exert a more pronounced inhibitory effect on the bioactivity of the microorganisms compared to Cd(II). It was observed that the combined presence of Cu(II) and Cd(II) did not exert synergistic effects on the microorganisms. Kinetic study conducted for the REACT period showed that the addition of PAC had minimized the inhibitory effect of the heavy metals on the bioactivity of microorganisms.

Matched MeSH terms: Copper/chemistry*
Estimates of mineral intakes using food composition tables vs measures by inductively-coupled plasma mass spectrometry: Part 2: sodium, potassium, magnesium, copper, zinc

Shimbo S, Zhang ZW, Miyake K, Watanabe T, Nakatsuka H, Matsuda-Inoguchi N, et al.

Eur J Clin Nutr, 1999 Mar;53(3):233-8.
PMID: 10201806

To examine the accuracy of food composition table (FCT)-based estimation of dietary nutrient element intake in reference to the instrumental measurement by inductively-coupled plasma mass spectrometry (ICP-MS), as an extension of the first part of this study.

Matched MeSH terms: Copper/administration & dosage*
Natural and anthropogenic trace-metal input into the coastal and estuarine sediments of the straits of Malacca

Din ZB

Bull Environ Contam Toxicol, 1995 Nov;55(5):666-73.
PMID: 8563198
Matched MeSH terms: Copper/analysis
Fulltext 1,1'-Carbonyldiimidazole-copper nanoflower enhanced collapsible laser scribed graphene engraved microgap capacitive aptasensor for the detection of milk allergen

Subramani IG, Perumal V, Gopinath SCB, Mohamed NM, Ovinis M, Sze LL

Sci Rep, 2021 10 21;11(1):20825.
PMID: 34675227 DOI: 10.1038/s41598-021-00057-4

The bovine milk allergenic protein, 'β-lactoglobulin' is one of the leading causes of milk allergic reaction. In this research, a novel label-free non-faradaic capacitive aptasensor was designed to detect β-lactoglobulin using a Laser Scribed Graphene (LSG) electrode. The graphene was directly engraved into a microgapped (~ 95 µm) capacitor-electrode pattern on a flexible polyimide (PI) film via a simple one-step CO2 laser irradiation. The novel hybrid nanoflower (NF) was synthesized using 1,1'-carbonyldiimidazole (CDI) as the organic molecule and copper (Cu) as the inorganic molecule via one-pot biomineralization by tuning the reaction time and concentration. NF was fixed on the pre-modified PI film at the triangular junction of the LSG microgap specifically for bio-capturing β-lactoglobulin. The fine-tuned CDI-Cu NF revealed the flower-like structures was viewed through field emission scanning electron microscopy. Fourier-transform infrared spectroscopy showed the interactions with PI film, CDI-Cu NF, oligoaptamer and β-lactoglobulin. The non-faradaic sensing of milk allergen β-lactoglobulin corresponds to a higher loading of oligoaptamer on 3D-structured CDI-Cu NF, with a linear range detection from 1 ag/ml to 100 fg/ml and attomolar (1 ag/ml) detection limit (S/N = 3:1). This novel CDI-Cu NF/LSG microgap aptasensor has a great potential for the detection of milk allergen with high-specificity and sensitivity.

Matched MeSH terms: Copper/chemistry*

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