Clay has been regarded as very important natural industrial materials. All these industries exploit the properties that clay can be molded into any shape and fired to dry without losing its form. A study was carried out on clay samples from eight sites in the north-eastern part of Peninsular Malaysia. The study was accomplished by using X-ray diffraction (XRD) technique. The x-ray diffraction spectra obtained enable the determination of the lattice spacing associated with the types of clay and nonclay minerals present in the samples. Results of the study shows that the major components of clay minerals present in all samples studied are kaolinite and illite. The presence of kaolinite is confirmed by firing test in which the kaolinite diffraction peaks disappeared upon heating the samples at 600 o C. The presence of non-clay minerals such as quartz, mica, feldspar and chlorite are also observed.
Radon gas has been known as one of the main factors that cause breathing complications which lead to lung cancer, second only after smoking habit. As one of the most commonly found Naturally Occurring Radioactive Materials (NORM), its contribution to background radiation is immense, and its contributors, Uranium and Thorium are widely available on Earth and have been in existence for such a long time with long half-lives. Indoor radon exposure contributed by building materials worsens the effects. The probability of inhaling radon-polluted air and being surrounded by it in any buildings is very high. This research is focused on the detection of radon emanation rate from various building materials which are commonly being used in Malaysia. Throughout this research, common building materials used in constructions in Malaysia were collected and indoor radon exposure from each material was measured individually using Tight Chamber Method coupled to a Continuous Radon Monitor, CRM 1029. It has been shown that sand brick is the biggest contributor to indoor radon compared to other samples such as sand, soil, black cement, white cement, and clay brick. From the results, materials which have high radon emanation could be reconsidered as building materials and mitigation action can be chosen, suitable to its application.
Being an imperative material for man either used as building materials, pottery or as components in material industry and technology, knowledge of clays elemental contents is important. In the present study ten clay samples obtained from various locations in North-West Peninsular Malaysia were used. Majority of the clays were economically manufactured to be used as building materials or pottery. The objective of study was to determine the main elemental contents of the samples, and relate the results to the types of minerals, as well as to compare them with clays from other studies. In the study X-ray Fluorescence (XRF) coupled to samples dilution method and standard calibration samples was used. The elements detected in the study were Si, Al, Fe, Ti, K and Ca. Depending on locations, the percentage concentration ranged between 24.8 – 32.4 for Si, 10.8 – 19.0 for Al, 0.09 – 2.12 for Fe, 0.08 – 1.13 for Ti, 0.45 – 3.39 for K and trace amount of Ca and P. However, Mg that normally found in typical clay was not found in the studied samples. Comparing the oxide of the major elements with other studies, it was found that the clay samples contained mixtures of kaolinite (two-layered structure) and illite (three-layered structure).
There are many essential and non-essential elements including metals and radionuclides present in vegetables. Howeve r, the accumulation of the several metals and radionuclides might cause the contamination to vegetables itself. Green m ustard (Brasissca rapa var. Parachinesis L.) was selected to represent the vegetable in this study. Objectives of this stud y are to determine the concentration of metals and radionuclides in the samples and to calculate the enrichment factor ( EF) and also to estimate the uptake, base on biological accumulation coefficient (BAC), for the various parts of selecte d vegetables. Three farmlands in the Cameron Highlands were studied namely Bharat, Kg Raja and Bertam area. The g reen mustard and soil samples were collected during the harvest season. Samples were dried, ground and sieved prior t o analysis. Analyses for both samples were done by using X-rays Fluorescence Spectroscopy (XRF) to measure the conc entration of Fe, Zn, Hg, U and Th. The concentration of all elements in the soils is lower than their concentration in the control soil, except for Zn, U and Th. The concentration of all elements in Green Mustard is lower than their concentrat ion in the soil where it was grown. The EF values in the Brasissca rapa var. Parachinesis L are lower than 2 except for U and Th, indicating some degree of contamination due to anthropogenic activities or naturally origin. The BAC values show that Zn and Hg were accumulated in the green mustard, depending on where the plant grows.
Many studies were carried out throughout the world on radon measurement in water especially drinking water for it can cause problem to human health. This study is an attempt to measure the level of radon present in water collect from rivers and lakes. Data gathered from this study provides important information about radiation levels in water at selected sites, because radon gas is the largest contributor to natural radioactive radiation exposure to humans. Exposure to radon gas can cause lung cancer. Liquid scintillation counting (LSC) has been applied to determine the activity concentration of radon ( 222 Rn) in water. Water samples were collected from, ex-mining lake in Perak, Sok River in Kelantan, Tembeling River in Pahang. Water samples were prepared in polyethylene bottles mixed with liquid scintillator and stored for 3 weeks to allow 222 Rn and its progeny to reach the equilibrium, and the activity concentrations ranged from 0.24-1.27 Bq/L, and 0.029 – 0.155 Bq/L for radon and radium respectively.
Ground water contain natural radioactivity associated with uranium and thorium that present naturally in rocks and soils. Humans may be exposed to the emission of energetic alpha particle from supported radon decaying process in this water when it is inhaled or ingested. Assessment of supported radon in ground water was carried out using fourteen ground water samples from Cameron Highlands. The measurement was accomplished by degassing the water samples using pump and then allowing the gas to flow into specially constructed 0.0191 m8 metal chamber. The activity concentration of supported radon in water sample was measured using continuous radon monitor inside the radon chamber. Measurement was carried out at one hour interval for twenty four hours. The hourly supported radon concentration was found to stabilize after about 8 hours. The stabilized concentration was used to determine supported radon activity concentration in the water samples. Results of the study show that depending on the sampling location, the activity concentrations of supported radon are in the range from 0.09 - 0.48 Bq/L which is lower than the activity concentration of radon in drinking water as proposed by USEPA (11 Bq/L).
Taman Negara is a famous tourism destination for nature lover in Malaysia. The area is well kept from human activities and disturbances. Since there is no data for human exposure to natural radiation, there is a need to do this study. It will give a baseline data for surface dose and radionuclide concentrations and one can estimate the external hazards index for the visitor to this unexplored area, i.e. UiTM-Perhilitan research station, Kuala Keniam, Taman Negara, Malaysia. The surface dose rate measurements were done in-situ using portable radiation survey meter at the surface and 1 m above the surface. The top soil samples were taken using hand auger up to 15 cm depth at nine locations around research station. Samples were brought back to the UiTM laboratory in Shah Alam, dried, ground to powder form, and sieved using 250 μm sieve. Then the uranium and thorium concentrations were analyzed using Energy Dispersive X-Ray Fluorescence (EDXRF).The mean value for surface dose rates on surface were 0.164 μSv/hr while the mean value for surface dose rates on 1m above the surface were 0.161 μSv/hr. The mean concentration of thorium was 2.62μg/g while the mean concentration of uranium was 0.61μg/g.
Measurement of major cation such as Na+, K+, and Ca2+ in water are normally carried out using
AAS, ICP-OES or flame photometry. In this study, an attempt was made to measure these cations
using Energy Dispersive X-ray Fluorescent Spectrometry (EDXRF). Hot spring s water was taken from varies hot spring in Selangor and divided into two portions that is filtered and unfiltered. 5 mL of water samples were pipette into a special liquid cups (sample holders) which has a thin mylar film underneath. The MiniPal4 XRF instrument was used in this study. The resolution for the instrument use is 145 keV with energy resolution at 5.9 keV. The spectrum of cations were analysed by using MiniPal/MiniMate software to determine the cations concentration. For K+ and Ca2+, Al-thin filter was used and default filter was used for Na+. The concentration of Na+ obtained for filtered and unfiltered samples were ranged from 38.00 to 66.05 and 43.26 to 76.95 ppm. Meanwhile, concentrations of K+ for filtered and unfiltered samples were ranged from 2.42 to 8.07 and 6.18 to 29.28 ppm. Concentrations of Ca2+ for filtered and unfiltered samples were ranged from 2.59 to 10.94 and 3.18 to 12.99 ppm.
137 Cs is well known man-made radionuclide produced from nuclear industry. Nuclear weapon tests and nuclear accidents had contributed to presence of 137 Cs into the worldwide environment including Malaysia. It has spread out to the entire world through the air and water current. Since Cameron Highlands is located at high altitude, there is a better chance of the 137 Cs to settle down on the trees and later the soil underneath. In this study, the soil samples were taken at the slopes of two different tea plantation areas namely A and B. The soil samples were oven dried, ground, sieved and packed and sealed properly in plastic containers before measurement. Each plastic container contains around 450 g of sample. The measurement of 137 Cs activity concentration was done using HPGe detector gamma spectrometer. The spectrum was analyzed using Gamma Vision software to calculate the activity concentration of 137 Cs with energy peak of 661.66 keV. The activity concentration of 137 Cs found in the samples ranged from 0.23 to 1.90 and 0.11 to 3.01 Bq/kg for tea plantation A and tea plantation B, respectively. From the activity concentration of 137 Cs result, it was comparable to the others research regarding to 137 Cs in the soil around Asian.
The issue of water quality is a never ended issue and becoming more critical when considering the presence of natural radionuclides. Physical parameters and the levels of radionuclides may have some correlation and need further attention. In this study, the former tin mine lake in Kampong Gajah was chosen as a study area for its past historical background which might contribute to attenuation of the levels of natural radionuclides in water. The water samples were collected from different lakes using water sampler and some in-situ measurement were conducted to measure physical parameters as well as surface dose level. The water samples were analyzed for its gross alpha and gross beta activity concentrations using liquid scintillation counting and in-house cocktail method. Gross alpha and beta analyzed using in-house cocktail are in the range of 3.17 to 8.20 Bq/L and 9.89 to 22.20 Bq/L; 1.64 to 8.78 Bq/L and 0.22 to 28.22 Bq/L, respectively for preserved and un-preserved sample. The surface dose rate measured using survey meter is in the range of 0.07 to 0.21 μSv/h and 0.07 to 0.2 μSv/h for surface and 1 meter above the surface of the water, respectively.
The presence of 226 Ra in water is a great concern in human life since it can cause health risk to a certain extent. In the state of Kelantan, being known of its granitic area, there is a lack measurement of 226 Ra content in river water, since water is the major source of water supply. According to the INTERIM National Water Quality Standards for Malaysia (INWQS), 226 Ra activity concentration in water cannot exceed 0.1 Bq/L. For this reasons, this research was planned to carry out a systematic measurement of water along Sungai Kelantan. Liquid Scintillation Counting was used for measurement of 226 Ra in water samples from Sungai Kelantan mainly in district of Kuala Krai. In this paper, the results obtained is about 26 water samples, filtered and unfiltered, collected along Sungai Lebir, Sungai Sok and Bukit Sabah. Thus, the assessment activity concentration of 226 Ra in river water was obtained as well as annual effective dose for consumption of drinking water.
Anthropogenic airborne depositions of 210Po,
210Pb and 210Po/210Pb in the mosses and surface soils
collected at the vicinity of a coal-fired power plant were studied. The purpose of the study was to
determine activity concentrations of 210Po,
210Pb and 210Po/210Pb for assessing their variation
accumulation in the mosses and surface soils collected at the vicinity of a coal-fired power plant.
Other purposes were to determine their concentration factor (CF) in relation to track the potential
source of those radionuclides and to identify most suitable moss species as a biological indicator
for atmospheric deposition contaminants. In this study, different species of moss Leucobryum
aduncum, Campylopus serratus, Syrrhopodon ciliates and Vesicularia montagnei were collected in
May 2011 at the area around 15 km radius from Tanjung Bin coal-fired power plant located in
Pontian, Johor. The activity concentrations of 210Po,
210Pb and 210Po/210Pb in mosses were in the
range of 76.81 ± 4.94 – 251.33 ± 16.33 Bq/kg dry wt., 54.37 ± 3.38 – 164.63 ± 11.64 Bq/kg dry wt.
and 1.10 – 2.00, respectively. Meanwhile the ranges for those radionuclides in the surface soil
were 33.53 ± 2.10 – 179.67 ± 12.15 Bq/kg dry wt., 20.55 ± 1.33 – 106.62 ± 6.64 Bq/kg dry wt. and
1.61 – 2.44, respectively. Corresponding high ability of Leucobryum aduncum to accumulate more
210Po and 210Pb, wide geographical distribution, most abundant and high CF, therefore, the
findings can be concluded this species was the most suitable as a biological indicator for
atmospheric deposition contaminants such as 210Po and 210Pb. Furthermore, it is clear the
accumulation of 210Po and 210Pb in mosses might be supplied from various sources of atmospheric
deposition such as coal-fired power plant operation, industrial, agriculture and fertilizer activities,
burned fuel fossil and forest; and other potential sources. Meanwhile, the
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.
Recently, Malaysia has taken a positive step toward providing a better water quality by introducing more water quality parameters into its Water Quality Standard. With regard to the natural radionuclides that may present in the water, 3 parameters were introduced that is gross alpha, gross beta and radium which need to be measured and cannot exceed 0.1, 1.0 and 1.0 Bq/L respectively. This study was conducted to develop a more practical method in measuring these parameters in aqueous environmental samples. Besides having a lot of former tin mining areas, some part of Malaysia is located on the granitic rock which also contributes to a certain extent the amount of natural radionuclides such as uranium and thorium. For all we know these two radionuclides are the origin of other radionuclides being produced from their decay series. The State of Kelantan was chosen as the study area, where the water samples were collected from various part of the Kelantan River. 25 liters of samples were collected, acidify to pH 2 and filtered before the analysis. Measurement of these parameters was done using liquid scintillation counter (LSC). The LSC was set up to
the optimum discriminator level and counting was done using alpha-beta mode. The results show that gross alpha and beta can be measured using scintillation cocktail and radium and radon using extraction method. The results for gross alpha, gross beta, 222Ra and 226Ra are 0.39-6.42, 0.66-16.18, 0.40-4.65 and 0.05-0.56 Bq/L. MDA for gross alpha, gross beta and radium is 0.03, 0.08 and 0.00035 Bq/L respectively.
A study was carried out to determine short term diurnal radon concentration at five locations in Malaysia. Two locations (KG & AP) are former tin mining areas that has been converted to housing area and training centre respectively, one a relatively new city (SA), that was formerly a rubber and oil palm plantation area, one older cities (KB) and one housing complex by the sea (LP). The study was carried out in 2005, 2006 and 2007 using a diffused-junction photodiode sensor continuous radon monitor. The monitor is recognized by the USEPA. In each location, measurements were carried out on at least ten sites. Former tin mining areas of KG and AP shows up to seven times higher indoor average than the average in the other three locations. However the indoor average in all locations is still below the action level of 4 pCiL-1. For outdoor, the former tin mining areas average concentration was higher than the global average of 0.4 pCiL-1. For the twenty four hours temporal variation the trend indicated that former tin mining areas concentration are always higher, and at time up to six fold higher. The hourly variation of all locations follows an identical trend of high concentration during early to late morning and drop in the afternoon till evening. The outdoor twenty four hour temporal average of former tin mining areas is consistently higher than the outdoor global average of 0.4 pCiL-1. The strong correlation between indoor and outdoor concentration at AP, indicates that indoor radon might originates from outdoor environment. The study was also extended to estimate the effective dose (mSvyr-1) of Rn-222 to the public.
The existence of Naturally Occurring Radioactive Materials (NORM) such as K-40 was studied all over the world for their characteristics and effects on human and environment. K-40 exist in the earth crust with the concentration about 1.8 mg/kg or 481 Bq/g.. In this study, the level of K-40 in soil samples were measured using gamma spectrometer equipped with hyper pure germanium detector. The samples were collected from an oil palm cultivated area of Jengka 15, in Maran District, Pahang. The results show the level of K-40 activities at various locations. The activities of K-40 are in the range 52.9-150.5 Bq/kg and total potassium concentrations are 1.60-4.50%. There are no correlation between activities of K-40 with elevation i.e. R2= 0.0885.