All humans are exposed to variety of ionizing radiation sources from natural radiation (IAEA, 1989) and man-made (Grasty dan LaMarre, 2004). Exposure to natural ionizing radiation by humans (UNSCEAR, 2000; Achola et al., 2012) is an on-going (Jabbar et al., 2008) and cannot be avoided (Kannan et al., 2002). Annual dose human accumulated from natural ionizing radiation exposure in average is 2.4 mSv (UNSCEAR, 2000). Radiation dose exposure accumulated by human could happen in two conditions which are internal exposure (64%) and external exposure (36%) (UNSCEAR, 2000; ICRP 103, 2007). Natural ionizing radiation dose exposure accumulated by human were dominated by two main sources. They are the cosmic radiation from outer space and ionizing radiation from radiation transmitter or primordial radionuclide (WHO, 1961) from soil, building material, house, rocks, water, flora, fauna and air (UNSCEAR, 2000; Khoshbinfar and Moghaddam, 2010; ICRU, 2011).
Measurement of natural ionizing radiation from terrestrial gamma radiation had been conducted by almost all countries around the world such as Cyprus (Tzortzis, 2003), Austria (Wallova et al., 2012), Nigeria (Jibiri, 2007), Brunei (Lai et al., 1999), Oman (Goddard, 2002), Hong Kong (Tso and Li, 1992), Switzerland (Buchli and Burkart, 1989), Costa Rica (Mora et al., 2007), Syria (Aissa and Jubeli,1997), Sweden (Kock and Samuelsson, 2011), Rusia (Ramzaev et al., 2006), Egypt (Ibrahim et al., 1993), Lebanon (Samad et al., 2013), Pakistan (Tufail et al., 2006), Brazil (Yoshimura et al., 2004), and Spain (Quindos et al., 1994).
There are few locations that had been found to emit a high dose rate of natural terrestrial gamma radiation. They are Ramsar, Iran – 105, 000 nGyhr-1; Guarapari beach, Brazil – 90, 000 nGyhr-1; volcanic rocks geology area in Southwest France – 10, 000 nGyhr-1; tin ore and rare earth mineral location in Sichuan, China – 9,140 nGyhr-1; volcanic rocks area (Oligocene-Miocene era) in center of Big Baku and Sumgayit city in Azerbaijan – 8770 nGyhr-1 (UNSCEAR, 2000; 2008); heavy minerals deposited area (monazite) in Erasama and Chhatrapur, along Orissa beach, India – 5000 nGy hr⁻1 (Mohanty, et al., 2004); heavy minerals deposited area (monazite) in Chavra, along Kerala beach, India – 3767 nGyhr-1 (Ramasamy et al., 2013), and in San Vincente, Filipina – 1558 nGyhr-1 (UNSCEAR, 2000; 2008).
The study and survey of terrestrial gamma radiation and environmental radioactivity is a very important base study (Fritz et al., 2015; Engelbrecht, 2012; Kucukomeroglu et al., 2012) to present scientific data of radioactivity level and natural radiation for certain location or regions (Ramli et al., 1997; 2003; UNSCEAR 2000; 2008). Present evaluation of radioactivity level and natural radiation is very important (Mandić dan Dragović, 2010) for detail evaluation on radiology implications towards public and environment (Reddy et al., 2003) if there is nuclear accidents (Quindos et al., 1994), global nuclear fallout (Pálsson et al., 2013; Hamzah et al., 2012; Ahmad et al., 2010) and contamination or the released of radioactive sources from rare earth mining industry, wasted from TENORM (Technologically Enhanced Naturally Occurring Radioactive Materials), and etc. (Merdanoĝlu dan Altınsoy, 2006; Ateba et al., 2010).
In Malaysia preparation to enter nuclear era as estimated by Perbadanan Kuasa Nuklear Malaysia on the year of 2031 (MNPC), which is 10 years beyond the years estimated (2021) by OECD-NEA (2014), base data of radioactivity level and ionized radiation are needed (Quindos et al., 1994; Saito et al., 2012; Fritz et al., 2015) to fulfill the requirements of radiology impact assessment based on radionuclide spread and nuclear fallout as outlined by ICRP (International Commission for Radiological Protection) (ICRP 43, 1985), IAEA (International Atomic Energy Agency) and LPTA (Lembaga Perlesenan Tenaga Atom Malaysia) (IAEA, 2003). In a normal operation, base data of environment is important to control statutorily the released and spread of radionuclides from nuclear energy production (Fritz et al., 2015). In a radionuclides released or leaking cases, survey or monitoring data could give an answer to a question whether there is abnormality of radioactivity radiation level (Engelbrecht, 2012).
On top of that, radiation base level and background radioactivity data documentation before the construction of nuclear reactor and nuclear facility or their operation is one of criteria listed by IAEA in their guideline for choosing a location for nuclear power plant (IAEA, 1963). It is also the main recommendation in routine monitoring for public protection by ICRP (ICRP 43, 1985). In IAEA symposium held in Bombay on Mac 1963, background radiation monitoring network had to be done before and at the time of nuclear power plant operation. This includes the phase of nuclear power plant operation disqualification (IAEA, 1963). Beside that, radiation level and radioactivity mapping are important also as government broadcasting to convince public when there are issues on public safety and ecology systems security towards nuclear materials use especially in nuclear power plant (Menoux et al., 1963; Ramli, 2007).
Radiological mapping has been done in Peninsular Malaysia, but no detailed natural environmental radiological studies have been carried out in Sarawak and Sabah. Population health risks due to exposure to natural radiation sources are unknown. No reference of base level for future changes in the radiological environment due to human activities or trans-boundary nuclear event incidents and their relations to population health.
There is a significant correlation between the in-situ (direct) measured terrestrial gamma radiation dose rate (TGRD) with underlying geological formation and soil type of the study area and the health risk to the population. Research is needed to establish measured background data of natural environmental radioactivity and terrestrial gamma radiation dose rate (TGRD) in Borneo, Malaysia. A study of relations between the terrestrial gamma radiation dose rate (TGRD) measured with the existing geological formation & soil type can be use to assess the public radiological health risk due to exposure to natural radioactivity base on the radiological mapping. Figure 1 shows Sabah geological distribution in a map (Department of Geological Survey Malaysia, 1987).
Natural radioactive materials under certain conditions can reach hazardous radiological levels. Ninety nine percent (99%) of the total ionizing radiation exposure to the population (excluding medical exposure) was known to be due to the natural radiation sources (UNSCEAR, 2000). Natural environmental radiation arises mainly from primordial radionuclides such as 40K (Potassium) and also from 238U (Uranium) and 232Th (Thorium) decay series. Natural radioactivity can be found almost everywhere; in soil, water, air, and the universe (Kurnaz, 2013).
Gamma radiation emitted from primordial radionuclides is one of the main external sources of radiation on earth (UNSCEAR, 1993, 2000). Conceptually, this research is relevant to the Malaysian National Policy on Industry 4.0 (IR 4.0), since it involving the application of IR 4.0 technology such as Big Data Analytics (collection and analysis of natural environmental radiological data), System Integration and Augmented Reality (computer-generated radiological map in digital format). This project then can be evolving as a platform for nuclear emergency real time computer simulation and integration with nuclear security monitoring devices (Internet of Things - IoT).
In principal, this research is geared to boost the Malaysian government and local communities toward natural radiological safety, and create public awareness on the environmental health issues. The outputs from this project are relevant to the Guideline LEM/TEK/74 issued by Malaysian Atomic Energy Licensing Board (AELB), particularly to find out/in determine whether the existing natural environmental radioactivity level in the research area need to be subject to legal controls under the provisions of the Atomic Energy Licensing Act 1984 (Act 304) or not.
In addition, this project also in accordance with the main objective mentioned in the Malaysian National Policy on the Environment (DASN 2002), i.e., to achieve a clean environment, safe, healthy, and productive environment for present and future generations and aligned with the mission stated in the National Policy on Science, Technology & Innovation (NPSTI 2016), i.e., to advancing and mainstreaming STI at all levels and in all sectors. The total land area of Sabah is nearly 73,904 square kilometers (28,534 square miles). Sabah and Sarawak (Borneo of Malaysia) making up about 60.04% of the total area of Malaysia.