Radioactivity levels and health risks due to radionuclides in the soil of Yalova, Northwestern Turkey

Naturally occurring radionuclide of terrestrial origin [also called primordial radionuclide] are present in various degrees in all media in the environment, including the human body itself. Their concentrations in environment decrease continually by decaying. The main objective of this study is to evaluate the radioactivity levels and health risks due to terrestrial radionuclide in soil of Yalova, northwestern Turkey. For this purpose, activity concentrations of radionuclide in soil and the environmental outdoor gamma dose rates [terrestrial and cosmic] have been investigated in the city of Yalova. In addition, maps for the radionuclide activity concentrations of soil and the outdoor gamma dose rates distributions have been plotted for the region. The average activities of radionuclide, [238]U, [232]Th, [226]Ra, [40]K, and [137]Cs in the soil were determined as 17.95 [8.5-37.3] Bq/kg, 26.87 [3.8-43.9] Bq/kg, 22.36 [8.3-41] Bq/kg, 419.32 [197.1-950.0] Bq/kg, 2.53 [0.5-13.4] Bq/kg, respectively, in the region. The average outdoor gamma dose rates due to terrestrial and cosmic radiations were found to be 49 nGy/h and 35 nGy/h with the total of 84 nGy/h outdoor gamma exposure rate in the region. Annual effective dose due to environmental outdoor gamma radiation exposures was determined as 103 nSv with the excess lifetime cancer risk of 0.042 x 10[-2] in the region. The results of the study were discussed with the studies done in the close cities and the worldwide averages

Activity concentrations of [232]Th, [226]Ra and [40]K and gamma radiation absorbed dose rate levels in farm soil for the production of different brands of cigarette tobacco smoked in Nigeria

Presently, the British-American Tobacco Company [BAT] located in Ibadan, Oyo State is the only tobacco producing company in Nigeria accounting for about nine different brands of cigarette tobacco smoked in the country. The tobacco leaves are produced from some farmlands located in Oke-Ogun area of Ibadan where special fertilizers are used for the growing of the tobacco leaves. The use of this fertilizer may enhance natural radionuclide contents in the farm soils and through root uptake be accumulated in the leaves. In this study, soil samples from three farmlands used for the production of the tobacco leaves were collected in order to determine the activity concentrations of [226]Ra, [232]Th and [40]K in the farm soil. Measurements for the determination of the activity concentrations were carried out using gamma-ray spectrometry comprising a lead-shielded 76 mm _ 76 mm NaI[Tl] detector crystal [Model 802 series, Bicron Nal] coupled to a Canberra series 10 plus multichannel analyzer [MCA] [model 1104] through an preamplifier base. Results of measurements showed that the average activity concentrations of the natural radionuclides in the soil samples across the three farms varied from 2550.4 +/- 154.6 to 3208.9 +/- 188.7 Bq kg[-1] for [40]K, 33.1 +/- 11.9 to 39.9 +/- 9.3 Bq kg[-1] for [226]Ra, while for [232]Th it varied between 51.98 +/- 8.4 and 56.08 +/- 17.51 Bq kg[-1]. The activity concentrations of these radionuclides and gamma absorbed dose rates due to the concentration of these radionuclides were found to be higher than world average values while those of the control farm values were lower to world averages and the tobacco leaf farms. From the results obtained the fertilizer type used on the farmlands for the tobacco leaf production was very rich in [40]K with typical values greater 2000 Bq kg-[1]. Also there may be possible high signatures of [210]Pb and [210]Po in the tobacco leaves and the cigarette samples smoked in the country. This is a subject for future research consideration given the fact that alpha radiation plays a major role in the etiology of lung cancer

Radium and Radon exhalation studies of soil

Everyone is exposed to radon because it is present everywhere with varying concentrations. Radon and its progeny are well established as lung carcinogenic. Track etch technique using LR-115 plastic track detectors has been used to measure the effective radium content and radon exhalation rates in soil samples collected from urban area of Etah district of Uttar Pradesh province in Northern India. The values of effective radium content are found to vary from 27.87 to 45.14 Bq.kg-[1] with a mean value of 34.98 Bq.kg-[1]. The mass exhalation rates of radon vary from 2.38 _ 10[-6] to 3.86 _ 10[-6] Bq.kg[-1].d[-1] with a mean value of 2.99 _ 10-6 Bq.kg[-1].d[-1]. The surface exhalation rates of radon have been found to vary from 6.19 _ 10[-5] to 10.03 _ 10[-5] Bq.m [-2].d[-1] with a mean value of 7.77 _ 10[-5] Bq.m [-2].d[-1]. Radon exhalation study is important for understanding the relative contribution of the material to the total radon concentration found inside the dwellings. The values of radium and radon exhalation rates are found to be below the safe limit recommended by OECD, 1979

Distribution of radionuclide in the forest soils [Western Ghats-India]

The presence of radionuclides in the soil, measures need to be taken to minimize the radiation dose to humans. It is mostly gamma-emitting radionuclides that contribute to the radiation dose in long term behavior of these radionuclides in soil may determine the extent to which such countermeasures need to be applied. The activity concentration of these radionuclides in the soil samples that collected from the Longwood forest at western Ghats have been analyzed using Gamma spectrometry. The mean activities of 238U, 232Th and 40K were observed 26.261Bq/kg, 53.614 Bq/kg, 204.084 Bq/kg, dry weight, respectively. The average value of dose rate was calculated 55.48 nGy/h by applying the conversion factor where as the environmental dosimeter shows the absorbed dose rate at 1m high is 96.96 nGy/h. It was observed that the activity concentration of primordial radionuclides and the gamma dose rate measurements by ERD and from soil is relatively higher than world average

Dose de radiação ionizante decorrente do uso de fertilizantes agrícolas / Ionizing radiation dose due to the use of agricultural fertilizers

Dentre os diversos agentes existentes no meio ambiente que podem nos expor a diferentes riscos e efeitos, há a radiação ionizante cujo conhecimento da dose é de importância para o efetivo controle e prevenção dos seus possíveis danos aos seres humanos e ao ambiente. A transferência de radionuclídeos dos adubos para/e dos solos para os alimentos podem resultar em incremento na dose interna ao serem consumidos pelo ser humano. Este trabalho avalia a contribuição dos fertilizantes para o aumento da dose de radiação ionizante no meio ambiente e no ser humano. Amostras de fertilizantes, de solos e de hortaliças produzidas em solos adubados foram analisadas através da espectrometria gama com o uso de um detector semicondutor de germânio hiperpuro. Medidas de dose ambiente também foram realizadas com dosímetros termoluminescentes. Nas amostras de solos adubados foram obtidos valores de atividades específicas de 36 a 342 Bq/kg para K-40, de 42 a 142 Bq/kg para U-238 e de 36 a 107 Bq/kg para Th-232. Nas hortaliças os valores variaram de 21 a 118 Bq/kg para K-40 e para os elementos da série do urânio e tório os valores foram menores que 2 Bq/kg. Para fertilizantes o valor máximo obtido foi de 5800 Bq/kg para K-40, 430 Bq/kg para U-238 e 230 Bq/kg para Th-232. As médias dos valores de fator de transferência solo-planta não foram significativamente diferentes entre os tipos de hortaliças analisados. A dose efetiva comprometida anual de 0,882 µSv devido à ingestão de K-40 das espécies estudadas é bem pequena em relação ao valor de referência de 170 µSv dada pela United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR, 2000). A dosimetria termoluminescente forneceu valores de taxa de equivalente de dose ambiente anual entre 1,5 e 1,8 mSv, sem diferenças entre locais cultivados e não cultivados. Através dos resultados obtidos, não foi observada uma transferência significativa de radionuclídeos dos fertilizantes para os alimentos e para os solos nas condições adotadas neste trabalho e conseqüentemente não há incremento de dose de radiação devido à prática da adubação.

Níveis de radioatividade natural decorrente do radônio no complexo rochoso da Serra de São Vicente, SP / Levels of natural radon-radioactivity in the São Vicente, SP, rock massif

OBJETIVO: Realizar monitoração passiva e integrada do radônio em várias amostras de águas, solos e locais fechados do complexo rochoso da Serra de São Vicente, SP, com o intuito de avaliar a distribuição de ocorrência deste gás radioativo naquele local. MATERIAIS E MÉTODOS: A técnica utilizada consistiu em expor detectores plásticos policarbonatos (SSNTD) do tipo Makrofol E, na geometria de copo fechado, ao radônio emanado das amostras de águas coletadas dos solos e ao acumulado em ambientes internos (residências e cavidades nas rochas) existentes no complexo rochoso de São Vicente. RESULTADOS: Os valores obtidos para os teores de radônio variaram entre 8,1 e 36 Bq/l para as fontes de água natural, entre 68 e 610 Bq/m³ nas residências, entre 0,41 e 3,46 kBq/m³nos solos e entre 0,72 e 5,85 kBq/m³ nas cavidades do Maciço de São Vicente. CONCLUSÃO: Para algumas residências e na maioria das fontes de água estudadas, os teores de radônio encontrados neste trabalho estiveram acima dos limites máximos propostos por organismos internacionais. Recomenda-se, portanto, que ações de intervenção sejam implementadas para a dissipação do radônio, tanto nessas residências como durante a coleta das águas para fins de consumo.

OBJECTIVE: The objective of this study was to perform a passive and time-integrated radon monitoring in several soil and water samples and indoor environments of the São Vicente, SP, rock massif with the purpose of evaluating the presence and distribution of that radioactive gas in this region. MATERIALS AND METHODS: The technique employed consisted of exposing Makrofol E-type polycarbonate plastic detectors (SSNTD), using the closed cup method, to radon emanated from ground water samples and to the gas accumulated inside indoor environments (dwellings) and inside rock cavities existing in the São Vicente rock massif. RESULTS: The radon concentration values obtained ranged from 8.1 to 36 Bq/l in natural ground waters; between 68 and 610 Bq/m³ in dwellings; from 0.41 to 3.46 kBq/m³ in soils and from 0.72 to 5.85 kBq/m³ inside rock cavities of the São Vicente rock massif. CONCLUSION: In some dwellings and in most of ground water samples, the radon concentration values found in this study have exceeded the maximum levels proposed by international agencies. Thus, intervention actions are recommended for radon dissipation in dwellings and during consumption water collection.

Uranium, radium and radon exhalation studies in geological samples belonging to some areas of punjab, using track etching technique.

With a view to prospect the uranium, radium and radon concentration and related health risk assessments in areas of Muktsar and Ferozepur districts in Punjab, the fission track registration technique has been used for the analysis of water and soil samples. Uranium content in water ranged from 5.47 to 10.19 microg/l(-1) and 6.28 to 11.74 microg/l(-1) for Muktsar and Ferozepur respectively. Uranium content in soil samples of Muktsar and Ferozepur ranged from 1.14 to 1.90 mg/kg(-1) and 1.26 to 2.44 mg/kg(-1) respectively. Radium concentration in these soil samples has been found to vary from 3.97 to 15.94 bq/kg(-1) and 7.24 to 24.14 bq/kg(-1) for Muktsar and Ferozepur respectively. The radon exhalation values were calculated in terms of area (E(A)) and mass (E(M)). The values of E(M) ranged from 4.9 to 20.6 (mbqkg(-1) hr(-1)) for Muktsar and 9.4 to 31.3 (mbqkg(-1)hr(-1)) for Ferozepur and values of E(A) ranged from 173 to 728 (mbqm(-2)hr(-1)) for Muktsar and 330 to 1102 (mbqm(-2)hr(-1)) for Ferozepur district. These values in general are low and not significant from health hazard point of view. The values of uranium concentration in water samples of these areas are lower than those reported for soil and water samples of Himachal Pradesh. These values are also lower than those reported by Singh et al. for the rocks belonging to uranium and copper mines of Bihar.

practical determination method of potassium traces in foodstuffs by the use of natural [40]k radiation

A new approach is presented for experimental determination of the potassium traces in foodstuffs, soil, sediment and plants, by use of natural [40]K radiation. Potassium maintains the salt balance in plant and animal cells and is important for healthy metabolis. Its role is often likened to that of the oil in an engine. There are actually three potassium isotopes'. [39]K, a stable isotope, is the most abundant, at 93.26% of the total; [41]K is next in abundance at 6.73% and is also a stable isotope. The potassium isotope of interest is a radioactive isotope, [40]K. It is present in all potassium at a very low concentration, 0.0118%. It has a very long half-life, 1,260,000,000 years. When it decays 89% of the events give rise to the emission of a beta ray with maximum energy of 1.33 Mev. The other 11% of the decays produce a gamma ray with an energy of 1.46 Mev. The long half-life and low abundance might seem to imply that this radioisotope, [40]K, is of little or no consequence, so it is usually ignored. In fact the knowledge that all potassium contains this radioactive isotope does not seem to be widely known. Very few of the discussions about potassium mention its radioactivity, which seems to imply that either it is not known or that this trivial level can be safely ignored. This radioactive element is vital for our good health. It is an element that is essential for the body's growth and maintenance. Potassium is also necessary in order to maintain normal water transport between the cells and body fluids. It also plays an essential role in the response of nerves to stimulation and in the contraction of muscles

Concentration of natural radionuclides in soil and assessment of external exposure to the public in Tehran

Natural radionuclides in soil constitute a significant component of the background exposure sources of the population. A meaningful contribution to the total dose from natural sources comes from terrestrial radionuclides such as 238U, 232Th and 40K. The concentrations of natural radionuclides of 238U, 232Th and 40K in surface soil [5 cm depth] of Tehran have been measured by gamma spectrometry. The samples were dried and homogenized and measured for 60k seconds after radionuclides secular equilibrium, using a high purity germanium [HPGe] gamma-ray spectrometer. The high energy resolution of this type of detector is particularly useful for activity measurements of uranium and thorium chain members due to their complex spectras. The absorbed dose rates in air were also measured by using ionization-chamber at the point where soil samples were collected which includes terrestrial and cosmic rays. The natural gamma emitting terrestrial radionuclides in soils are directly relevant to outdoor exposure. The average activity concentrations of 238U, 232Th and 40K in different districts of Tehran were found to be 24, 28 and 635 Bq kg-1, respectively. The average outdoor gamma absorbed dose rate in air at 1 meter above ground was calculated as 102 nGy h-1. By using the data obtained in this study the average annual effective dose equivalent for a person living in Tehran Sv. According to data of 66 soil samples was found to be about 125 measurement covering 22 districts in Tehran, the average outdoor gamma dose rate in air due to terrestrial and cosmic radiation was found to be about 102 nGy h-1 and the average annual effective dose equivalent for a person living in Tehran Svmicrois about 125

Investigation of depleted uranium contamination in south west of Iraq

The application of DU emanation for first time contaminated certain areas in the south west region of Iraq after the second Gulf war [1991]. These contaminated areas were discovered in 1994. Radioactive contamination was detected using the nuclear enterprise PCM5/1 in soil samples collected from two regions near by grazing lands. This study was done for assessment of DU contaminated soil in the regions under study. Portable detector was used for radiation measurement of the contaminated area. Samples from each region were selected and taken to Baghdad kept in plastic bags for gamma ray spectroscopy measurement. Gamma-ray spectroscopy system consists of high purity germanium [HPGE] detector surrounded by appropriate shield. The measurement of detector efficiency using [GDR] computer programs, supplied by Canberra Company was used to analyze gamma-ray spectrum. The activity of [234] Th, [235]U, [238]Pa and other natural isotopes were measured. The measurement by gamma -ray spectrometry system showed that six samples were heavily contaminated with DU, because the presence of [243]Pa and [235]U peak and the percentage ratio between [235] U/[238]U were less than 0.005, when both international mathematical methods, namely IAEA and Kosovo, were used. Because of existence of radiation equilibrium between [234]Th and [234]Pa, the measurements should be accurate. The result showed that six of the samples were heavily contaminated with DU and there is a good agreement between the two methods. Because of the accuracy and ease of the Kosovo method, it is recommended for future investigations

Indoor radon in Thailand: a study with particular reference to its sources.

Measurements of radon gas were carried out on each floor of the four tall concrete buildings. The results show clearly that levels of radon concentration on the higher floors of the buildings were mostly comparable and occasionally were much higher than the ground-floor in contact with the earth. Hence, the findings indicate that the source of indoor radon is not only the surrounding soil but also other sources in the buildings, i.e. most likely radium-containing building materials.