ASSESSMENT OF BACKGROUND IONIZING RADIATION LEVEL OF SCRAP METAL DUMPSITES IN DUTSE TOWN, JIGAWA STATE, NIGERIA.

Abstract

The level of awareness of the radiation hazards from indiscriminate dumping of scrap metals is
very low in developing countries. In this study, the background ionizing radiation level of scrap
metal dumpsites in Dutse Town, Jigawa State, Nigeria was assessed. A hand-held Radiation
Alert Inspector (RAI) was used and a total of Ten (10) scrap metal dumpsites were randomly
selected. Four readings were taken in Counts Per Minute (CPM) and micro Sievert per
hour(μSv/hr) at four (4) different selected points on each of the dumpsites. The value of
exposure dose rate (in μSv/hr) was used to estimate the Absorbed Dose D (in nGy/hr), Annual
Effective Dose (in mSvy-1) and Excess Lifetime Cancer Risk respectively. The results show that
the mean exposure dose rate range from 0.01225 to 0.02125 μSv/hr. All the values of exposure
dose rate were found to be below the standard value of 0.133 μSv/h. The mean value of the
Absorbed Dose D varies from 12.25 to 21.25 nGy/hr respectively. The calculated mean Annual
Effective Dose was found to be in the range of 0.015023 to 0.026061 mSvy-1. These values are
below 1.0 mSvy-1 dose limit recommended by the International Commission on Radiological
Protection (ICRP). The mean Excess Lifetime Cancer Risk range from 0.052582 to 0.091214 and
are lower than the world limit of 0.29 × 10-3. The study indicates that the people working and
living within the study area are safe and are not exposed to high doses of radiation as result of
activities in the dumpsite. However, continuous monitoring of background radiation in the
dumpsites is recommended.