Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 31312
Radioactivity Assessment of Sediments in Negombo Lagoon Sri Lanka

Authors: H. M. N. L. Handagiripathira


The distributions of naturally occurring and anthropogenic radioactive materials were determined in surface sediments taken at 27 different locations along the bank of Negombo Lagoon in Sri Lanka. Hydrographic parameters of lagoon water and the grain size analyses of the sediment samples were also carried out for this study. The conductivity of the adjacent water was varied from 13.6 mS/cm to 55.4 mS/cm near to the southern end and the northern end of the lagoon, respectively, and equally salinity levels varied from 7.2 psu to 32.1 psu. The average pH in the water was 7.6 and average water temperature was 28.7 °C. The grain size analysis emphasized the mass fractions of the samples as sand (60.9%), fine sand (30.6%) and fine silt+clay (1.3%) in the sampling locations. The surface sediment samples of wet weight, 1 kg each from upper 5-10 cm layer, were oven dried at 105 °C for 24 hours to get a constant weight, homogenized and sieved through a 2 mm sieve (IAEA technical series no. 295). The radioactivity concentrations were determined using gamma spectrometry technique. Ultra Low Background Broad Energy High Purity Ge Detector, BEGe (Model BE5030, Canberra) was used for radioactivity measurement with Canberra Industries' Laboratory Source-less Calibration Software (LabSOCS) mathematical efficiency calibration approach and Geometry composer software. The mean activity concentration was found to be 24 ± 4, 67 ± 9, 181 ± 10, 59 ± 8, 3.5 ± 0.4 and 0.47 ± 0.08 Bq/kg for 238U, 232Th, 40K, 210Pb, 235U and 137Cs respectively. The mean absorbed dose rate in air, radium equivalent activity, external hazard index, annual gonadal dose equivalent and annual effective dose equivalent were 60.8 nGy/h, 137.3 Bq/kg, 0.4, 425.3 mSv/year and 74.6 mSv/year, respectively. The results of this study will provide baseline information on the natural and artificial radioactive isotopes and environmental pollution associated with information on radiological risk.

Keywords: Radioactivity, Sediments, Gamma Spectrometry, lagoon

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 0


[1] S. Murugesan, S. Mullainathan, V. Ramasamy and V. Meenakshisundaram. Radioactivity and radiation hazard assessment of Cauvery River, Tamilnadu, India. Iran. J. Radiat. Res., 2011; 8(4): 211-222
[2] V. Kannana, M.P. Rajana, M.A.R. Iyengara, R. Rameshb. Distribution of natural and anthropogenic radionuclides in soil and beach sand samples of Kalpakkam (India) using hyper pure germanium (HPGe) gamma ray spectrometry. Applied Radiation and Isotopes 57 (2002) 109–119
[3] D. E. Walling, Q. He & T. A. Quine, Use of caesium-137 and lead-210 as tracers in soil erosion investigations. Tracer Technologies for Hydrological Systems (Proceedings of a Boulder Symposium, July 1995). IAHS Publ. no. 229, 1995
[4] Taskin H, Karavus M, TopuzogluA, Hindiroglu S, Karahan G (2009). Radionuclide concentrations in soil and Lifetime cancer risk due to the gamma radioactivity in Kirklareli, Turkey. J. Environmental Radioactivity. 100: 49-53
[5] Shams Issa, Mohamed Uosif, Reda Elsaman. Gamma radioactivity measurements in Nile River sediment samples. Turkish J EngEnvSci (2013) 37: 109 – 122
[6] He, Q., Walling, D.E., 1996. Interpreting particle size effects in the adsorption of 137Cs and unsupported 210Pb by mineral soils and sediments. J. Environ. Radioact. 30, 117-137.
[7] Schulling, R.D., De Meijer, R.J., Riezebos, H.J., Scholten, M.J., 1985. Grain size distribution of different mineral in a sediment as a function of their specific activity. Geology enMijnbouw 64, 199-203.
[8] Ligero, R.A., Ramos-Lerate, I., Barrera, M., Casas-Ruiz, M., 2001. Relationships between sea-bed radionuclide activities and some sedimentological variables. J. Environ. Radioact. 57, 7-19.
[9] Cho, Y.H., Jeong, C.H., Hahn, R.S., 1996. Sorption characteristics of 137Cs on to clay minerals: effect of mineral structure and ionic strength. J. Radioanal. Nucl. Chem. 204, 33-43.
[10] United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), 1982.
[11] United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), 1988. Sources, effects and risks of ionizing radiation. Report to the General Assembly, With Annexes, United Nations, New York.
[12] United Nations Scientific Committee on Effects of Atomic Radiation, “Exposures from Natural Radiation Sources”, UNSCEAR Report, New York, 2000.
[13] Silva, E. I. L.; Katupotha, J.; Amarasinghe, O.; Manthrithilake, H.; Ariyaratna, R. 2013. Lagoons of Sri Lanka: from the origins to the present. Colombo, Sri Lanka: International Water Management Institute (IWMI). 122p. doi: 10.5337/2013.215
[14] IAEA 1989 Technical Report Series No. 295 Measurement of Radionuclides in Food and the Environment: a Guidebook (Vienna: IAEA)
[15] Technical specification sheet of Broad Energy Germanium Detectors (BEGe) issued by Canberra Industries Inc. (, BEGe-SS-C40426-BE5030 detector details)
[16] Mantazul IC, Alam MN, Hazari SKS (1999) Distribution of radio nuclides in the river sediments and coastal soils of Chittagong Bangladesh and evaluation of the radiation hazard. Applied Radiation and Isotopes, 51: 747755. 29
[17] Ziquiang P, Yin Y, Mingqiang G (1988) National radiation and radioactivity in China. Radiation Protection Dosimetry, 24: 29-38
[18] Megumi K., Oka T., Doi M., Kinura S., Tsujimoto T., Ishiyama T. &Katsurayama K., 1988 Relationships between the concentration of natural Radionuclides and the Mineral composition of the surface soil. Radia. Protect. Dosim, 24, 69-72
[19] Doretti, L., Ferrar, D., Barison, G., Gerbasi, R., Battiston, G., 1992. Natural radionuclides in the muds and waters used in thermal therapy in AbanoTerme, Italy. Radiat. Prot. Dosim. 45 (1), 175–178.
[20] Arogunjo AM, Farai IP, Fuwape IA (2004) Dose rate assessment of terrestrial gamma radiation in the delta region of Nigeria. Radiation Protection Dosimetry, 108: 73-77.
[21] Al-Trabulsy, H.A.; Khater, A.E. and Habbani, F.I. (2011): Radioactivity levels and radiological hazard indices at the Saudi coastline of the Gulf of Aqaba. Radiation Physics and Chemistry 80: 343–348
[22] Al-Zamel, A.Z., Bou-Rabee, F., Olszewski, M., Bem, H., 2005. Natural radionuclides and 137Cs activity concentration in the bottom sediment cores from Kuwait Bay. Journal of Radioanalytical and Nuclear chemistry 266, 269-276.
[23] Zare, M.R., Mostajaboddavati, M., Kamali, M., Abdi, M.R., Mortazavi, M.S., 2012. 235U, 238U, 232Th, 40K and 137Cs activity concentrations in marine sediments along the northern coast of Oman Sea using high-resolution gamma-ray spectrometry. Mar. Pollut. Bull. 64 (9), 1956–1961
[24] Ibrahiem NM, Abd El, Ghani AH, Shawky SM, Ashraf EM, Farouk MA (1993) Measurement of radioactivity levels in soil in the Nile Delta and middle Egypt. Health Physics, 64: 297-299.
[25] Delune RD, Jones GL, Smith CJ (1986) Radionuclide concentrations in Louisiana soils and sediments. Health Physics, 51: 239-244.
[26] Beck HL (1972) The physics of environmental radiation fields. Natural radiation environment II. CONF-720805 P2. Proceedings of the Second International symposium on the Natural Radiation Environment.
[27] UNSCEAR, 1988. Sources and effects of ionizing radiation. United Nations Scientific Committee on the Effect of Atomic Radiation, United Nations, New York.
[28] Caroline NihinlolaIwetan, IbiyinkaAgboolaFuwape, Adeseye Muyiwa Arogunjo, Ganiyu Obor. Assessment of Activity Concentration of Radionuclides in Sediment from Oil Producing Communities of Delta State, Nigeria. Journal of Environmental Protection, 2015, 6, 640-650
[29] J. Beretka, P.J. Mathew. Natural radioactivity of Australian building materials, industrial wastewaters and by-products. Health Physics, 48 (1985), pp. 87–95
[30] Arafa W (2004) Specific activity and hazards of granite samples collected from the Eastern Desert of Egypt. J Environ Radioact 75:315–327
[31] Orgun Y, Altınsoy N, Gultekin AH, Karahan G, Celebi N (2005) Natural radioactivity levels in granitic plutons and groundwaters in Southeast part of Eskisehir, Turkey. ApplRadiatIsot 63:267–275
[32] Yang HS, Nozaki Y, Sakai H, Nagaya Y, Nakamura K (1986) Natural and man-made radionuclide distributions in Northwest pacific deep-sea sediments: rates of sedimentation, bioturbation and 226Ra migration. Geochem J 20:29–40
[33] K. Mamont-Ciesla, B. Gwiazdowski, M. Biernacka, A. ZakRadioactivity of building materials in Poland. Natural radiation environment, Halsted Press, New York (1982)
[34] I. Akkurt and K. Günoğlu Natural Radioactivity Measurements and Radiation Dose Estimation in Some Sedimentary Rock Samples in Turkey. Research Article | Open Access, Volume 2014 |Article ID 950978 |
[35] Faweya E. B., Alabi F. O. and Adewumi T., Determination of radioactivity level and hazard assessment of unconsolidated sand and shale soil samples from petroleum oil field at Oredo (Benin, Niger Delta-Nigeria). Arch. Appl. Sci. Res., 2014, 6 (2):76-81
[36] Y Örgün, N Altınsoy, AH Gültekin, G Karahan, N Celebi. Natural radioactivity levels in granitic plutons and ground waters in Southeast part of Eskisehir, Turkey, Applied Radiation and Isotopes (2005) 63 (2), 267-275