7 research outputs found
Evaluating the radiological health compliance of some beach environments in Delta State
Beaches constitute recreational and resort centres in the environment of which radiation is part. With respect to radiation protection practice, the International Radiation Protection bodies from time to time recommend certain exposure limits for different environments. In this study, a Raderlert 100 radiation meter was used to measure the gamma radiation levels in four beaches in Delta State, Nigeria. The purpose is to ascertain whether or not the radiation levels in these resort centres conform with international stipulations and consequently infer if their respective environments are radio logically health compliant such that personnel as well as specified members of the public (customers) are not at radiological risk. Results indicate a dose rate range of (0.010 – 0.015) mRh-1. These are generally higher than the 0.013 mRh-1 recommendation of ICRP. Results also indicate an Annual Effective Dose Equivalent AEDE range of (0.19 – 1.598) mSvy-1 which are higher than the recommended 1 mSvy-1 .Results further indicate an Excess Life Cancer Risk ECLR range of (0.64 – 1.74) x 10-3. These are higher than the 0.29 x10-3 world average. Thus it is concluded that the radiation levels in the environments of the studied beaches exceed international radiation regulatory stipulations.Therefore, in this their present states, these environments are radio logically unhealthy for their respective workers and members of the public.Keywords: Radiation levels; Beaches; Radiological health complianc
A study of the thermoluminescence fading characteristics of natural marble phosphor
The thermoluminescence (TL) response fading behaviour of natural marble obtained from the South Western Basement Complex of Nigeria for varying gamma irradiation doses were investigated for the purpose of ascertaining if this material can suffice as a TL dosimeter. Irradiation was done using a 60Co gammacell irradiator while a Victoreen TL Reader was employed for the TL measurements. The result indicate that the material exhibits a logarithmically exponential decay having the equation TL (Au) = -7.02 lnTs + 71.11. Fading is observed to be initially fast then gradual and thereafter almost constant after about one month post irradiation storage like is characteristic of most common TL dosimeters. The result also shows that of the three peaks revealed by the analyzed glow curve of this TL phosphor, the lower temperature peak occurring at 115 °C is most suitable for this dosimetric application.Key words: Fading, Natural marble, Thermoluminescence
Determination of the radiological health indexes of using natural kaolin
Kaolin (China clay) is used for various purposes such as in the manufacture of fine porcelain, pottery making, paper industry etc and is thus a valuable geological material. A qualitative and quantitative determination of the natural radionuclides contained in samples obtained from Delta State Nigeria was carried out using a well - calibrated highly efficient NaI(TL) detector. The consequent radiological health indexes were then calculated. The radionuclides detected belong to the 238U and 232Th decay and the non series 40K. The mean specific activities of 226Ra, 228Ra and 40K varied from 95.3 - 96.3, 99.7 – 99.9 and 537.2 – 543.6 Bqkg-1 respectively. These levels are slightly higher than corresponding values obtained by other investigators elsewhere not in Nigeria. Radium-equivalent activity was found to be 280.3 Bqkg-1 The external hazard index is 0.76 while the mean annual effective dose equivalent is 0.16 mSvy-1 . Since the hazard index is less than unity and the determined dose equivalent is below the internationally recommended limit of 1mSvy-1 for members of the public, it is concluded that the use of natural kaolin of Nigerian origin does not pose any radiological effect of consequenceKeywords: Nigerian kaolin, wide applications, radiologically friendl
Outdoor background gamma radiation levels in rural environments of Enugu east, Nigeria
The human populace is constantly irradiated both in the indoor and outdoor environment, as such, estimating the doses of radiation circulating in the environment is key in examining the health exposure to the populace. In this regard, in-situ measurements of outdoor radiation exposure rates in five rural communities of Enugu East local government area of Enugu State, Nigeria were made in this present study using a portable factory calibrated GQ GMC-320 PLUS radiation survey meter held at 1.0 m above ground level alongside a GPS for geographical location. The exposure rates in mRh-1 were converted to radiation hazard indices using well established relations. The results revealed that the mean background radiation exposure levels for Akpoga, Nchetanche, Obinagu and Onuogba are generally lower than ICRP reference level of 0.013 mRhr-1 for outdoor environments while that of Nkwubor exceeded the limit by 7.7%. The radiation absorbed dose, equivalent dose, annual effective dose equivalent and excess lifetime cancer risks were calculated. The purpose is to assess the radiological risk due to radiation exposure in the communities. The terrestrial gamma radiation levels at some locations in the communities are somewhat low and high. The radiation dose values are generally below the values considered to cause immediate harmful effects and thus do not pose any immediate health hazards to the residents at this present moment. However, continuous exposure and accumulation of low radiation doses may pose radiological health risks to the people living in the areas in future.
Keywords: Background radiation; dose levels; health effect; rural communitie
Evaluation of the background ionizing radiation and health status of personnel in laboratories at some Tertiary Institutions in Delta State
Exposure to ionizing radiation even at low doses may be harmful to cells. In this study, an in-situ measurement of Background Ionization Radiation (BIR) exposure rate in laboratories Tertiary Institutions in Delta State, Nigeria was carried outusing a Geiger Muller counter (GMC 320+). The purpose is to estimate the BIR health parameter and hence predict the radiation health status of personnel in these laboratories. For all the measurements readings were taken three consecutive times at a height of one metre above the ground for each point. A geographical positioning system (GPS) was used to determine the coordinates of the study areas. The results indicate that the mean values of the exposure rates range from 0.05 – 0.17 μSv/hr for indoor and 0.08 – 0.14 μSv/hr for outdoor. The obtained annual effective dose equivalent (AEDE) values for the selected institutions range from 0.63 – 1.02 mSv/yr for the indoor and 0.15 – 0.24 mSv/yr for outdoor. These values are within the recommended safety limit of 1.0 mSv/yr by the International Commission on Radiation Protection. The calculated mean excess lifetime cancer risk (ELCR) for the institutions range from 1.72 x 10-3 – 2.77 x 10-3 for the indoor environment. These values are higher than the 0.29 x 10-3 value recommended by United Nations Scientific Committee on the Effects of Atomic Radiation. This implies the laboratory personnel in these institutions are likely to develop cancer at the age of 55 years and above. There is the need for regular monitoring by the relevant body.
Keywords: Indoor/Outdoor Radiation, Annual Effective Dose Equivalent and Excess Lifetime Cancer Risk
Predicting the nutritional health status of locally produced palm oil using some physical parameters
Three physical properties of locally produced palm oil – viscosity, thermal conductivity and density for varying temperatures were determined. The values obtained were compared with corresponding internationally stipulated standard values using statistics of mean and graphs. The purpose of the comparison was to predict the nutritional health status of palm oil. Results show that the obtained mean values were (18.50 ± 5.35) Pa.s, (0.1429 ± 0.0042) W/m oC and (898.1 ± 0.28 kgm-3) for the locally produced palm oil as against (20.47 ± 5.68) Pa.s, (0.1677 ± 0.0006) W/m oC and (849.6 ± 5.47) kgm-3 for the standard. These represent respective errors of 10, 15 and 5 %. Results also show that the slopes of the respective relationships of these parameters with temperature at θ = 25 oC (RT) for instance are – 0.266 Pa.s/ oC , 0 and – 0.022 kgm/m3 oC for the locally produced while the values obtained using standard data are – 0.242 Pa.s/ oC, - 0.0008 W/m oC and – 0.442 kg/m3oC. The associated percentage errors are 7, 100 and 95. These pronounced errors give an indication that from the standpoint of the examined physical properties, the studied locally processed palm oil may not be as nutritionally healthy as the standard oil. Proper monitoring of the local palm oil mills by the relevant agency is therefore recommended.Keywords: Predict, Status, Locally produced, Palm oil, physical properties, nutritional healt
A revised mathematical solution to the Penne bioheat equation for deep rooted tissues using the variable separation method
The temperature distribution of tissues under the skin surface was obtained using Penne’s bio-heat equation and the separation of variables technique. The resulting solution indicated a slight temperature difference between the recorded skin temperature and the temperature of the tissue of interest (TOI), which is a direct indication of the TOI's temperature. According to the graphical analysis, temperature is proportionally related to time and tissue distance from the skin surface. As a result, the given analytic solution may be utilized to easily analyze deeprooted tissues while accounting for thermal properties