Calcium supplements: an additional source of lead contamination.

The risk posed by the quantity of heavy metal lead present in Ca supplements is of grave concern. Some lead levels have been measured up to the extent of regulatory limit set by the United States. Calcium supplements inevitably get contaminated with lead as both are naturally occurring elements having the same charge density.

Occupational exposure from external radiation used in medical practices in Pakistan by film badge dosimetry.

Occupational exposure data of workers due to external sources of radiation in various medical practices such as nuclear medicine (NM), radiotherapy and diagnostic radiology (DR) in Pakistan were collected and analysed. Whole-body doses of workers were measured by film badge dosimetry technique during 2003-2007. Annual average effective dose in NM, radiotherapy and DR varied in the range of 1.

Design and development of a portable gamma radiation monitor.

A portable gamma radiation monitor has been designed and developed. The monitor can be used effectively in the dose range from 0.07 to 500 mGy/h due to gamma rays of energy greater than 65 keV.

Evaluation of dietary status with respect to trace element intake from dry fruits consumed in Pakistan: a study using instrumental neutron activation analysis.

Instrumental neutron activation analysis has been utilized for the quantification of 24 major, minor and trace elements in dried apricots (Prunus armeniaca), dates (Phoenix dectylifera), figs (Ficus carica) and raisins (Vitis vinifera) using a low-power reactor as the neutron source. The weekly intakes of aluminium, arsenic, boron, calcium, chlorine, cobalt, chromium, iron, mercury, potassium, sodium, magnesium, manganese, molybdenum, antimony, selenium and zinc have been calculated and compared with the Recommended Dietary Allowance/Estimated Safe and Adequate Dietary Intake values through consumption of 100 g dried fruit. Fairly adequate levels of calcium, cobalt, iron, potassium and magnesium were determined in these dried fruits while the contribution of chlorine, chromium, molybdenum and sodium to the Recommended Dietary Allowance was found to be insignificant.

Investigation of the Occurrence of Human Errors in Treatment of Cancer Patients with External Beam Radiotherapy.

The main objective of clinical radiotherapy procedures is to deliver accurate doses to cancer patients. However, human errors can occur during the treatment planning and dose delivery that may result in under- or overexposure to the patient. Therefore the aim of the present study was to detect and quantify different types of errors that may occur during radiation treatment at the Nuclear Medicine, Oncology and Radiotherapy Institute (NORI) in Islamabad, Pakistan.

Sorption of traces of silver ions onto polyurethane foam from acidic solution.

The sorption of traces of silver ions onto polyurethane foam (PUF) has been investigated in detail. Maximum sorption of silver (K(d)=6109 cm(3) g(-1), %sorption>97.5%) has been achieved from 1 M nitric acid solution after equilibrating silver ions with approximately 29 mg PUF for 20 min.

Adsorption and thermodynamic characteristics of Hg(II)-SCN complex onto polyurethane foam.

The sorption of Hg(II) in the presence of sodium thiocyanate solution onto polyurethane (PUR) foam, an excellent sorbent, has been investigated in detail. Maximum sorption of Hg(II) is achieved from 0.1 M hydrochloric acid solution containing 7.

Adsorption of (99m)Tc-radiopharmaceuticals onto injection vials and syringes.

Unlabelled: Many groups have reported the adsorption or retention of (99m)Tc-radiopharmaceuticals on injection vials and disposable plastic syringes. Such an enormously high loss of radioactivity would result in poor images, radiation exposure, waste, and economic burdens. We therefore decided to investigate the extent of adsorption or retention of several (99m)Tc-radiopharmaceuticals on injection vials, rubber stoppers, and plastic syringes.

Instrumental neutron activation analysis of different products from the sugarcane industry in Pakistan--part 1: essential elements for nutritional adequacy.

Jaggery, brown sugar, white sugar, and molasses collected from the local sugarcane industry of Pakistan have been analyzed for essential elements in order to estimate their nutritional adequacy. Instrumental neutron activation analysis was used to determine Ca, CI, Co, Cr, Fe, K, Mg, Mn, Na, and Zn through sequential, short, medium, and long irradiation times. Maximum concentrations for most of these elements were determined in molasses, with lower concentrations determined in jaggery and brown sugar; white sugar contained trace amounts of all essential elements.

Sodium sulfate as an eluant for concentrated solution of pertechnetate.

Fission molybdenum-99 based technetium-99m chromatography generators are the most widely employed generator systems in the field of diagnostic nuclear medicine. In the first week these generators provide high specific volume activity Na99mTcO4, but in the second week the radioactive concentration of the eluate (99mTc) becomes 17% of that at the beginning of the first week. Low specific volume activity limits the clinical procedures (e.

The design and characteristics of direct current glow discharge atomic emission source operated with plain and hollow cathodes.

A compact direct current glow discharge atomic emission source has been designed and constructed for analytical applications. This atomic emission source works very efficiently at a low-input electrical power. The design has some features that make it distinct from that of the conventional Grimm glow discharge source.

A practical profile of integrated safety assessment of near-surface disposal of radwaste at PINSTECH.

Near-surface or shallow land disposal of radioactive waste has been the primary practice at the Pakistan Institute of Nuclear Science and Technology (PINSTECH). The adopted choice of this mode of disposal has been based on a study of the site and the quality and quantity of waste generated at the 5 MW reactor with HEU fuel. Specific measures regarding the radiation safety of the workers and environmental protection have been adopted.

Radiological impact of dietary intakes of naturally occurring radionuclides on Pakistani adults.

Daily dietary intakes of three naturally occurring long-lived radionuclides (232)Th, (238)U and (40)K were estimated for the adult population of Pakistan using neutron activation analysis (NAA), inductively coupled plasma mass spectrometry (ICP-MS) and atomic absorption spectrometry (AAS), respectively. The daily intakes of (232)Th ranged from 4 to 29 mBq, (238)U ranged from 17 to 82 mBq and (40)K ranged from 51 to 128 Bq. The geometric means of these intakes were 10 mBqd(-1) for (232)Th, 33 mBqd(-1) for (238)U and 78.

Non-occupational lead exposure and hypertension in Pakistani adults.

Hypertension is one of the most prevalent diseases in the developed and developing countries. Based on the long historical association and the provocative findings of blood pressure effects at low level of lead exposure a study was carried out to determine if an association existed between low blood lead concentration and hypertension. In this study the effects of low-level exposure to lead on blood pressure were examined among 244 adults using atomic absorption spectrometer.

Measurement of natural radioactivity in bottled drinking water in Pakistan and consequent dose estimates.

Natural radioactivity was determined in 11 different brands of commonly sold bottled drinking water in the federal capital Islamabad and Rawalpindi city of Pakistan using gamma spectrometry technique. Mean concentrations of 226Ra, 232Th and (40)K were found to be 11.3 +/- 2.

The potential of cost-effective coconut husk for the removal of toxic metal ions for environmental protection.

Coconut (Cocos nucifera) husk, an agricultural waste, has been thoroughly investigated for the removal of toxic Cd(II), Cr(III) and Hg(II) ions from aqueous media. The parameters like nature and composition of electrolyte, concentration of toxic ions, dosage of coconut husk, and equilibration time between the two phases were optimized for their maximum accumulation onto the solid surface. The effect of common ions on the uptake of metal ions has been monitored under optimal conditions.

Calculation of immersion doses from external exposure to a plume of radioactive material.

The immersion doses from external exposure to a Gaussian plume of noble gases accidentally released into the atmosphere have been calculated. A numerical integration procedure employing Gauss-Legendre of 64th order has been used. The numerical procedure allows calculating the dose rate at any downwind horizontal or vertical distance.

Simple elution aid for multiple, fractionated, and partial elution of 99mTc.

Objective: (99m)Tc obtained from (99)Mo/(99m)Tc generators is playing a key role in the majority of diagnostic scans performed in the world today. The availability of (99m)Tc can be increased if it is separated from (99)Mo after much shorter growth times (multiple elution). Fractionated elution may provide a high concentration of (99m)Tc, whereas partial elution will help reduce doses to nuclear medicine staff members.

Preparation and in vitro stability of (n,gamma) yttrium-90 hydroxyapatite.

Yttrium-90, produced by irradiating Y2O3 (15 mg) in the Pakistan Research Reactor (PARR-I) at a flux of approximately 1.5x10(14) neutrons/cm2/s, was used to prepare yttrium-90 hydroxyapatite particles for radiosynovectomy applications. The irradiated material was dissolved in concentrated hydrochloric acid, evaporated and taken up in distilled water.

Size-dependent superheating in confined Pb(111) films.

Molecular dynamics simulations have been carried out to explore superheating in Pb(111) films confined in an Al(111) matrix. The size dependence of the superheating has been investigated by varying the film size and keeping the host matrix unchanged. Melting is found to initiate in the interior of the film, which suggests intrinsic homogeneous nucleation.

Time-integrated thyroid dose for accidental releases from Pakistan Research Reactor-1.

The two-hourly time-integrated thyroid dose due to radio-iodines released to the atmosphere through the exhaust stack of Pakistan Research Reactor-1 (PARR-1), under accident conditions, has been calculated. A computer program, PAKRAD (which was developed under an IAEA research grant, PAK/RCA/8990), was used for the dose calculations. The sensitivity of the dose results to different exhaust flow rates and atmospheric stability classes was studied.

Ground water quality assessment using multi-rectangular diagrams.

A new graphical technique is proposed here for classifying chemical analyses of ground water. In this technique, a diagram is constructed using rectangular coordinates. The new diagram, called a multi-rectangular diagram (MRD), uses adjacent multi-rectangles in which each rectangle represents a specific ground water type.

Interwell tracing by environmental isotopes at Fimkassar Oilfield, Pakistan.

Water flooding is an important operation to enhance oil recovery. Movement of injected water is traced to test the performance of the water flood and verify suspected geological barriers or flow channels, etc. This paper describes the application of environmental isotopes as interwell tracers at Fimkassar Oilfield in Chakwal District, Pakistan.

Nutritional and radiological impact of dietary potassium on the Pakistani population.

The nutritional status of dietary potassium and the radiological impact of its isotope (40)K were estimated for the Pakistani population. Potassium concentration was determined in dietary samples by atomic absorption spectrometry. An average potassium concentration was 4.

Determination of lithium isotopic composition by thermal ionization mass spectrometry.

A mass spectrometric method has been proposed for the determination of the isotopic composition of lithium. It is based upon thermal ionization of LiOH loaded onto a single SiO2-coated Re filament. By this method, stable emissions of Li+ ion have been achieved for an extended period of time.