ASSESSMENT OF OUTDOOR BACKGROUND RADIATION AROUND SAKI WEST LOCAL GOVERNMENT

Background radiation is a measure of the level of ionizing radiation present in the environment at a particular location which is not due to deliberate introduction of radiation sources. It originates from a variety of sources, both natural and artificial. These include both cosmic radiation and environmental radioactivity from naturally occurring radioactive materials (such as radon and radium), as well as man-made medical X-rays, fallout from nuclear weapons testing and nuclear accidents. Radioactivity occurs naturally in certain elements, such as uranium, thorium, and radium, as well as in some isotopes of elements found in the Earth's crust. It is also artificially induced in nuclear reactions, such as those occurring in nuclear power plants or nuclear weapons. (usikalu et al., 2023). The studied area was in Saki town in Saki West local government of Oyo North in Oyo State, Nigeria. It lies in the southwestern part of the country. It lies at the latitude of 8.66700 North, and the longitude is 3.38300 East. The area has a landmass of 28,454square kilometers (11,077 square miles). The study was performed in an area, these sites are located from N8.68068º" to N 8.66973º" and from E 3.41438º" to E 3.40642º". Forty (40) locations were monitored to measure outdoor environmental gamma radiation dose rate. A real-time digital portable radiation monitoring device which is known as Gamma Scout was used for this study. Gamma Scout is German designed and manufactured, built with a solid Novadur exterior. The equivalent dose rate measured in the outdoor location within the area around Saki West LG Oyo State, ranged from 0.147 µSv/hr to 0.222 µSv/hr with a mean of 0.176 µSv/hr. The highest radiation concentration dose was found at location 26 (petrol station) and this may be due to the spillage small amount of naturally occurring radioactive materials like Radon, Uranium and thorium can be present in petroleum and the lowest radiation concentration rate was found at location 5 (Field) and this may be due to low level of naturally occurring radioactive isotopes by being far away from radiation sources. The estimated annual equivalent dose rate ranged from 0.147mS/yr to 0.222msv/yr with a mean of 0.299mSv/yr which was lower than the global level 0.48mSv/yr as presented by UNCEAR and maximum dose limit 1.0mSv/yr as presented by ICPR Therefore, it is concluded that the people in the selected environment are exposed to an insignificant health risk of background radiation