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  • Author or Editor: S. Rahman x
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Abstract  

Instrumental neutron activation analysis (INAA) and atomic absorption spectrophotometry (AAS) were used to verify the protocols for the quantification of zinc and magnesium in human whole blood. A study was conducted on group of volunteers consisting of 131 patients having cardiovascular diseases (CVD) and 23 malignant hypertension (MH) patients along with 432 control subjects with 218 male and 214 females. The elemental data of these elements has been exploited to establish the base line values in control subjects. The possibility of any relationship between blood Mg and Zn levels with CVD and MH has also been investigated. The mean blood Mg and Zn levels were found to be depleted in both CVD and MH patients as compared to normal subjects. In our findings Mg and Zn were found to have an inverse relation with systolic and diastolic pressure. The reliability of the methods was checked by the concurrent analysis of the IAEA reference material (RM) employing the optimized INAA and AAS protocols. The determined values by both techniques were found to be in good agreement with the IAEA reference values. The elemental data in whole blood samples of normal volunteers has also been compared with Mg and Zn contents reported by other countries.

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Abstract  

To understand the role of Cu and Zn in human blood both in controls as well as in cardiovascular (CVD) patients, whole blood samples of 181 CVD and 185 controls between the ages of 20–66 years were investigated. Instrumental neutron activation analysis (INAA) and flame atomic absorption spectrophotometric techniques were successfully employed to quantification Cu and Zn levels. The mean blood-Cu levels (1.50 mg L−1) were found as enhanced whereas Zn levels (5.88 mg L −1) were reduced in cardiovascular patients group as compared to 0.90 and 6.70 mg L−1 for Cu and Zn respectively in controls. Cu/Zn ratios for CVD patients are also higher than in control subjects. Negative correlation exists between Cu and Zn levels in both controls and patient groups. However, when the CVD patients were checked for their systolic and diastolic pressure it was found that copper concentrations in these patients was significantly increased (p < 0.001) with the rise of blood systolic pressure so a positive correlation was observed between copper and systolic pressure. Zn on the other hand has an inverse relation with systolic as well as diastolic pressure (p < 0.001). Total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol, and triglyceride (TG) in blood samples have also been determined and their probable role in the CVD complication has been observed. A positive correlation of blood-Cu with TC, TG, and LDL-C indicates that rise in blood-Cu levels may initiate the development of CVD. An increase in Cu/Zn ratio can instigate the cardiovascular risk factor. The findings from this study can definitely update our knowledge of the role of Cu and Zn in the development of CVD risk in humans.

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Abstract  

Instrumental neutron activation analysis (INAA) have been used to determine As, Br, Hg, Sb and Se in combination with atomic absorption spectrometry (AAS) as a complementary technique for the quantification of Cd and Pb in jaggery, brown sugar, white sugar and molasses. All sugar cane products were collected from the local sugar cane industry of Pakistan. The highest concentration of these potentially toxic elements was quantified in molasses; however, molasses together with jaggery, brown sugar and white sugar contains trace amounts of all of these elements. Due to very low concentration of Cd it could only be detected in molasses. To evaluate the percentage contribution of these elements in the sugar cane products to the weekly recommended values, intakes on weekly consumption of 100 g of each item have also been calculated which follow the pattern Br>Se>Pb>Hg>As>Sb. The elevated Br contents may be attributed to the use of Br-containing chemicals for fumigation; however, these contents are well within the tolerance levels. The estimated weekly intake of all toxic elements is very low indicating that sugar cane products can be safely ingested as part of the diets.

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Abstract  

Instrumental Neutron Activation Analysis (INAA) and Atomic Absorption Spectroscopy methodology was developed to characterize the hazardous and other inorganic trace element constituents in new and used domestic plastic food containers. INAA due to its non destructive, highly sensitive, multielement and low detection limits characteristics was found to be a good technique for the characterization of polymeric products. Through the variation of irradiation, cooling and counting protocols Al, Ba, Br, Co, Cr, Eu, Fe, Hg, K, Mn, Na, Nd, Sb, Sc, Th, Ti, V and Zn were determined, while Atomic Absorption Spectroscopy was used as complementary technique to quantify toxic inorganic elements such as Cd, Pb and Cu. These elements are thought to originate from the polymer manufacturing processes. It was found that there was gradual increase in the concentration of most of these elements from new to used plastic samples. Moreover it was also observed that these inorganic elements are present in higher concentrations in the lower grade containers as compared to the high quality containers. It was also observed that the good quality containers even with the long usage do not degrade to such an extent as the low quality containers.

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Abstract  

Tuna fish flesh homogenate, IAEA-436, was received under the IAEA Analytical Quality Control Services (AQCS) intercomparison programme. Instrumental neutron activation analysis (INAA) was used to determine Al, As, Br, Ca, Ce, Cl, Co, Cr, Cs, Eu, Fe, Hg, K, Mg, Mn, Na, Rb, Se, Sb, Sm, and Zn in this proposed reference material (RM). IAEA-407 (Fish Homogenate) and NIST-SRM-1572 (Citrus Leaves) were used for quality assurance (QA) purposes. Due to the very low levels of most elements in IAEA-436, large discrepancies were observed between our results for IAEA-436 and data cited by the IAEA.

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Abstract  

Air particulate matter (PM) was collected in two size fractions using stacked filter units (SFUs) provided by the International Atomic Energy Agency (IAEA) from the industrial area of Islamabad. Nucleopore polycarbonate filters were used for collecting from Oct 98 to Jun 99 the particulate matter in coarse and fine size fractions. The samples were characterized by the instrumental neutron activation analysis (INAA). About 33 elements were quantified using different irradiation and counting protocols.

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Summary  

A national intercomparison exercise was conducted to remove inconsistencies and improve analytical procedures in the measurement of hafnium and zirconium in zirconium ores. The ZH-A series of reference samples, prepared at the Pakistan Institute of Nuclear Science and Technology (PINSTECH), were used for this purpose. It was observed that measurement errors decreased with increasing Hf concentration (~298-17500 ppm) for most techniques, especially for AAS due to the sample preparation procedure required for this technique. Of all the tested techniques most reliable results were obtained with neutron activation analysis (NAA) for the measurement of Hf and Zr in such matrices.

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Abstract  

The contents of mercury and organic mercury in various types of seafood from various location in Malaysia were determined by neutron activation analysis. Total mercury was determined by instrumental neutron activation analysis (INAA) whilst organic mercury was determined by INAA after chemical separation. Samples were digested in acid media and into the solution was added copper ion and KBr to release organic mercury compound from sulphur component of the tissue. The organic mercury was then extracted into toluene and then treated with cysteine paper to convert the compound into sub-organo-mercury from. The paper was then transferred into polyethylene vials and irradiated in the MINT TRIGA Reactor. Analytical results of organic mercury in Indian mackerel (Rastrelliger kanagurta), Spanish mackerel (Scomberomurus commersoni), shrimp (Peneaus sp.), squid (Loligo sp.) and cockle (Anadara granosa) is in the range of 45%–94% of the total mercury.

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Abstract  

The proposed reference material from the International Atomic Energy Agency, namely IAEA-407 (Fish Homogenate) was analyzed using instrumental neutron activation analysis (INAA). 15 elements, Al, As, Cl, Co, Cr, Fe, Hg, Mg, Mn, K, Na, Sb, Se, V and Zn, were determined using two irradiations (5 minutes and 5 hours) and four countings. IAEA-MA-A-1/TM (Copepoda Homogenate), NIST-SRM-1566 (Oyster Tissue), NIST-SRM-1572 (Citrus Leaves) and NIST-SRM-1577a (Bovine Liver) were utilized as standards in the quantification step.

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