Super SPEC RS-125 radiation detector with large 2.0 x 2.0 NaI crystal and linear
energy ranging from 0.80 MeV to 1.2 MeV was used to measure the activities of primordial
nuclides and the radiation dose exposures rate in Iyana-Iyesi, Ota, southwestern Nigeria. The
measured activities vary from 17±0.02 Bqkg-1 to 30.49 ±0.01 Bqkg-1, 50.01 ±0.16 Bqkg-1 to
158.49±0.17 Bqkg-1, and 406.9±0.42 Bqkg-1 to 1275.48±0.82 Bqkg-1 for 238U, 232Th and 40K
respectively. The acquired gamma radiation dose rate range from 138.696 ±2.06 (nGyh-1) to
350.103±7.21 (nGyh-1) with mean value of 148.22 (nGyh-1), almost three times higher than the
recommended safe limit of 55 (nGyh-1). The measured activities and radiation dose rate were
engaged to estimate the annual outdoor effective dose, gamma index, excess lifetime cancer
risks and annual gonadal dose equivalent. It was observed from all the estimated parameters,
those values in the study area are well above the recommended safe limit for normal
background radiation. This suggest that the dwellers and those using the excavated
geomaterials from this area for construction purposes are exposed to very high radiation from
natural radionuclides. Further research to evaluate the mineralogy and geochemistry of the clay
deposits in the area is highly recommended

https://iopscience.iop.org/article/10.1088/1742-6596/852/1/012042/pdf

Measurements of radioactivity levels in part of Ota Southwestern Nigeria: Implications for radiological hazards indices and excess lifetime cancer-risks

Assessment of radiological parameters of soil in Kogi State, Nigeria

A study to assess the Indoor and Outdoor Background Ionizing Radiation (BIR) of Sheda Science and Technology Complex, Abuja has been conducted. An in-situ measurement using a portable factory calibrated radiation dose rate meter, Radiagem 2000, was used to ascertain the radiation level. The measured radiation dose rates were used to evaluate the radiological health hazards and radiation effective doses to different body organs using well established radiological relations. The results shows that the total Dose Rate (indoor and outdoor), the Total Annual Equivalent Dose (indoor and outdoor), total Annual Effective Dose Equivalent (indoor and outdoor) and the total Excess Lifetime Cancer Risk (indoor and outdoor) are 0.113±0.022 (μSv/h), 0.071±0.016 (μSv/h), 0.794±0.155 mSv/y, 0.0.124±0.074 mSv/y, 0.556±0.109 mSv/y, 0.087±0.020 mSv/y, 1.945±0.379, 0.304±0.104 respectively for the three zones. The dosage to organs received shows that the testes have the highest dose while the liver has the lowest dose (indoor and outdoor) for the three zones. Generally the study shows that the Annual Effective Dose Equivalents were within the permissible limits of 1 mSv/y for general public exposure recommended by the (ICRP). Also, the effective doses to different body organs are all below the recommended limits of 1 mSv/y. The calculated Excess Lifetime Cancer Risk values indicates that the chance of contacting cancer by workers and residents of the study area is not probable hence the study area could be said to be radiologically safe. Keywords: Ionizing Radiation, Equivalent Dose, Effective Dose, Excess Lifetime Cancer Risk

/pdf/assessment-of-indoor-and-outdoor-radiation-levels-and-human-3htn5wtf4y.pdf

Assessment of indoor and outdoor radiation levels and human health risk in Sheda Science and Technology Complex and its environ, Abuja, Nigeria

Environmental radiation measurement was carried out in an automobile mechanic village, Apo, Abuja, Nigeria. An in-situ measurement approach was adopted using RDS-200 Universal Survey Meter and a handheld Global Positioning System (Garmin GPS 76S) equipment. It was observed that the dose equivalent varied from 0.04 μSv/h to 0.22 μSv/h with a mean of 0.10± 0.03 μSv/h which is below the standard background radiation of 0.133 μSv/h The study also revealed that the average annual effective dose rate is approximately 0.20±0.06 mSv/yr which is lower than the value of 1.0 mSv/yr averaged over five consecutive years according to the dose limit placed by the Basic Safety Standards (BSS) SCHEDULE II and the International Commission on Radiological Protection (ICRP) REPORT 60. This indicates that the automobile technicians, craftsmen and the people living and working within the area are safe and are not exposed to high doses of radiation as a result of activities in the Apo Automobile Mechanic Village. Keywords : Radiation Measurement; Apo Automobile Mechanic Village; Background Radiation; DoseEquivalent; Annual Effective Dose; Automobile Technicians

https://www.ajol.info/index.php/jasem/article/download/105453/95485

Measurement of Gamma Radiation in an Automobile Mechanic Village in Abuja, North Central, Nigeria

This study presents result of outdoor absorbed dose rate and estimated annual effective dose rate from the naturally occurring radionuclides 238 U, 232 Th and 40 K around BirninGwari artisanal goldmine using Instrumental Neutron Activation Analysis (INAA). The results showed that the mean absorbed dose rate is 96.52 nGy/h with a standard deviation of 33.3 nGy/h and the standard error of 9.62 nGy/h the range falls between 26.67-123.85 nGy/h. The mean effective dose rate was estimated to be 0.675 mSv/year with a standard deviation of 0.234 mSv and standard error of 0.068 mSv and in range between 0.183-0.867 mSv. The mean annual effective dose rate from this work is lower than the 1mSv/year recommended by ICRP for public radiation exposure control.

http://maxwellsci.com/print/rjees/v5-252-255.pdf

Determination of Absorbed and Annual Effective Doses around Birnin Gwari Artisanal Goldmine, Kaduna State, Nigeria

This study presents result of outdoor absorbed dose rate and estimated effective dose from the naturally occurring radionuclides 232Th and 238U series 40K, around a Nuclear Research Reactor at the Centre for Energy Research and Training (CERT), Zaria, Nigeria. A high-resolution in situ -ray spectrometry was used to carry out the study. CERT houses a 30Kw Research Reactor and other neutron and gamma sources for Research and Training. The values of absorbed dose rate in air for 232Th, 238U and 40K range from 8.2±2.5-24.5±3.6 nGy h 1, 1.9±1.2-4.6±2.5 nGy h 1 and 12.2 ±5-38±6.7n Gy h 1 respectively . The estimated total annual effective dose outdoor for the sites range from 27.3-79.9 µSv y 1. This showed that radiation exposure level for the public is lower than the recommended value of 1 mSv y 1.Hence, the extensive usage of radioactive materials within and around CERT

/pdf/determination-of-absorbed-and-effective-dose-from-natural-4rvh613kg9.pdf

Simon Peter Malam

Papers

Determination of Absorbed and Effective Dose from Natural Background Radiation around a Nuclear Research Facility