Penilaian Dampak Bahaya Radiologis terhadap Radionuklida Natural di Pesisir Pulau Bengkalis

Abstract

Latar belakang : Radionuklida natural ditemukan hampir di semua media lingkungan, dan di lingkungan laut terdeteksi cukup tinggi karena adanya proses erosi, pelapukan dan daur ulang mineralyang mengalami perpindahan melalui badan air. Radionuklida natural tersebutdapat berpindah ke berbagai media, termasuk ke manusia melalui rantai makanan.Penelitian ini dilakukan untuk memberikan informasi dasar mengenai tingkat radioaktivitas di lingkungan perairan laut di Pesisir Pulau Bengkalis dan melakukan penilaian dampak bahaya radiologis melalui aktivitas ekuivalen radium (Raeq) dan indeks bahaya eksternal (Hex)serta laju dosis eksternal dari radionuklida natural.Metode: Metode deskriptif digunakan dalam penelitian ini dan metode pengambilan sample sedimen menggunakan metode purposive sampling. Sampelsedimen dikumpulkan dari 6 titik pengambilan sampel di pesisir Pulau Bengkalis, menggunakan sediment grab. Sampel kemudian dikeringkan dan dihomogenkan kemudian ditimbang sebanyak 1 kg. Pengukuran aktivitas radionuklida dilakukan menggunakan spektrometri gama dengan waktu cacah selama 3 hari. Aktivitas 226Ra ditentukan berdasarkan emisi sinar gamma 214Pb dan 214Bi. Aktivtias 232Th ditentukan berdasarkan emisi 212Pb dan 228Ac dan 40K ditentukan dari emisi pada 1461,8 keV. Hasil analisis akan digunakan untuk menghitung dampak radiologis di lingkungan mengunakan ekuivalen aktivitas radium dan indeks bahaya eksternal.Hasil: Aktivitas rata-rata berturut turut 56,45 ; 31,34 ; 26,04 ; 33,19 ; 30,00 dan 185,49 Bq/kg untuk radio nuklida226Ra, 212Pb, 214Pb, 214Bi, 228Ac dan 40K. Aktivitas terukur mempunyai kisaran nilai yang berdekatan dengan pengukuran di beberapa negara.Penghitungan nilai aktivitas ekuivalen radium (Raeq) berkisar dari 82,61 - 138 Bq/kg dan tidak melebihi nilai yang ditetapkan oleh ICRP (1990) dan OECD (179) yaitu sebesar 370 Bq/kg. Nilai indeks bahaya eksternal (Hex) masih dibawah 1, dengan nilai rata rata sebesar 0,31, dan laju dosis dari radionuklida natural sebesar 37,175 nGy/h.Simpulan:Aktivitas radionuklida natural di pesisirPulauBengkalismempunyai kisaran nilai yang berdekatan dengan pengukuran di beberapa Negara. Nilai aktivitas ekuivalen radium (Raeq) Yang terukur tidak melebihi nilai yang ditetapkan oleh ICRP (1990) dan OECD (179). Nilai indeks bahaya eksternal (Hex) masih dibawah 1, dan laju dosis yang diserap lingkungan dari radionuklida natural masih dibawah nilai rata rata dunia. Dengan demikian, dapat disimpulkan bahwa parameter radiologis radionuklida natural dalam sedimen di pesisir Pulau Bengkalis berada dalam batas yang dapat diterima. AbstractTitle : --Background: Natural radionuclides are found in almost all environmental media, and in the marine compartment have been detected relative high due to the process of erosion, weathering and recycling of minerals that come trough the water bodies. Radionuclides can move to various media, including to the humans through the food chain. This research was conducted to provide baseline information about the activity of radioactivity in the marine environment of the Bengkalis Island Coast and conduct radiological hazard impact assessments through equivalent radium (Raeq) and external hazard index (Hex) and external dose rates of natural radionuclides.Method: Descriptive methods were used in this study and the sediment sampling method used a purposive sampling method. Sediment samples were collected from 6 sampling points on the coast of Bengkalis Island, using sediment grab. The samples were then dried, homogenized and weighed 1 kg. Measurement of radionuclide activity was carried out using gamma spectrometry with counting time for 3 days. The 226Ra activity is determined based on 214Pb and 214Bi gamma ray emissions. The 232Th activity was determined based on 212Pb and 228Ac and 40K emissions determined from emissions at 1461.8 keV. The results of the analysis will be used to calculate the radiological impact in the environment using equivalent radium activity and external hazard index.Results: The average activity are 56.45; 31.34; 26.04; 33.19; 30.00 and 185.49 Bq/kg for radionuclides 226Ra, 212Pb, 214Pb, 214Bi, 228Ac and 40K respectively. The value of this activity comparable withthe activities in several countries.The calculation of radium equivalent activity (Raeq) values ranges from 82.61 - 138 Bq / kg and does not exceed the value 370 Bq / kg by ICRP (1990) and OECD (179). The external hazard index value (Hex) is still below 1, with an average value of 0.31, and the dose rate of natural radionuclides is 37,175 nGy / h.Conclusion: Natural radionuclide activity on the coast of Bengkalis Island has a range of values adjacent to measurements in several countries. The measured value of radium (Raeq) activity does not exceed the value set by ICRP (1990) and OECD (179). The external hazard index value (Hex) is still below 1, and the absorbed dose rate of natural radionuclides is still below the world average value. Thus, it can be concluded that the radiological parameters of natural radionuclides in sediments on the coast of Bengkalis Island are within acceptable limits.

The Natural Radionuclide Activity and the Risk of Potential Radiation in Health Effect: A Study on Beach Sand in Madura, Bali, and Lombok

“…It was understood that the beach sands in several other countries such as the Guangxi Province, China, and white sand in Langkawi, Malaysia had a slightly smaller average I value of 0.17 and 0.19 (22,34). However, there was also a report that the beach sand in other areas such as Southern India had a higher value of I (2.35) than this study (35). Even black sand on the island of Langkawi, Malaysia, had a 17-time higher I value (17) than in this study (22).…”

Numerical Solution of Radioactive Core Decay Activity Rate of Actinium Series Using Matrix Algebra Method

“…The radionuclide series in the form of Actinium 235 series was found in all environmental media, one of which was on the coast of Bengkalis Island. The radinuclide activity of the actinium series in the area has an average value that is still within reasonable limits (Makmur., 2019). Noviarty (2017) also adds that the radioactive activity of the actinium U-235 series ranges from 0.013 Bq / g found in rocks around Batan in Banten, so the danger posed is not too heavy.…”