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- Author or Editor: S. Topcuoĝlu x
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Abstract
The retention of137Cs in algal polysaccharides has been studied. Alginic acid showed higher retention value than the tested alginate samples. The retention of137Cs in carrageen types and agar was first investigated. The binding capacities were found to be equal for carrageenan types and agar.
Abstract
The excretion kinetics of110mAg in a gastropod species contaminated through water pathway has been studied under laboratory condition. The pattern of the excretion results can be represented by a monophasic linear regression function. The excretion coefficient and biological half-life were calculated. The biological half-life was found to be 33 days. The study suggests that the excretion rate of110mAg byN. intricata may be considered as a potential biomonitor on the shoreline of the Black Sea marine environment.
Abstract
Radiocesium (134Cs and137Cs) activity levels in mosses from the Black Sea area, northern Turkey, are reported following the Chernobyl accident during the period of 1989–1991. The cesium radionuclides were detected and measured in all the samples but other longlived radionuclides such as144Ce and106Ru were measured in only one sample. The present data support the fact that radioactivity monitoring in mosses can be useful to determine the lasting effect of radioactive contamination.
Abstract
Translocation and percent distribution of137Cs in different parts of the tea plant have been investigated from the foliar aborption and root uptake in Chemobyl contaiminated soil during 1987–1994. The results showed that the transfer of the radionuclide from soil to the plant occurred only in the roots during this long period. On the other hand, the present data confirmed that the new leaves of the plant directly accumulated137Cs from the stem in growing seasons after translocation into the stem from leaves during the Chemobyl accident. The natural depuration rate of137Cs in the stem part of tea plant is estimated as on effective half-life 1750 days.
Abstract
NAA has been applied to determine the concentration of K, As, Se, Zn, Cr, Cs, Fe, Co, Sb, Ni and Ca in sediments and a macroalgae species collected from the Küçükçekmece Lagoon and Marmara Sea. The lagoon sediment showed higher metal levels than the sea sediment. The metal contents in algae species are not changed significantly between months and sampling sites except Zn and Cr. The profile of the lagoon sediments was also investigated.
Abstract
The distribution of the anthropogenic (134Cs and 137Cs) and natural (238U, 232Th and 40K) radionuclide concentrations were studied in soil, foodstuff and bioindicator samples collected from the near site of the Medzamor Nuclear Power Plant at the border of eastern Anatolia of Turkey. For some time, the gross-a and b-concentrations were also determined in the water samples of the region and the absorbed dose rates in air at 1 m above ground were measured. The results showed no additional artificial contamination from the Medzamor Nuclear Power Plant before June 1996.
Abstract
The distribution of the naturally occurring radionuclides 238U, 232Th, 226Ra, 40K and 210Po and an anthropogenic radionuclide 137Cs in foodstuff, indicator organism sediment and soil samples in Emendere thermal spring area in western Anatolia were studied by alpha- and gamma-spectrometry. At the same time, the gross-
and 
concentrations are also determined in the mentioned samples and the thermal spring and other water samples. The results obtained showed that Emendere thermal spring and Emendere stream waters are unsuitable for consumption as drinking purpose. On the other hand, the people who live around the thermal spring area face no risk with consumption of the foodstuffs.
Abstract
Cesium-137 concentrations in red, brown and green algae have been studied for the calculation of natural depuration rates. The algae species were collected from the same population of the Black Sea stations during the period of 1986–1995. The natural depuration rates are estimated as biological half-lives. The pattern of depuration results represented by a single component for each algae division. The biological half-lives of137Cs in red (Phyllophora nervosa), green (Chaetomorpha linum) and brown (Cystoceira barbata) algae are estimated to be 18.5, 21.6 and 29.3 months, respectively.137Cs and40K activity levels and their ratios in algae species in two stations in Black Sea region of Turkey have been determined during the period of 1990–1995. The results showed that the Sinop region was more contaminated than the 
ile region on the Black Sea coast of Turkey from the Chernobyl accident.
Abstract
During the periods of 1997–1998, macroalgae, sea snail, mussel, fish and sediment samples were collected from different stations at Turkish Black Sea coast in order to determine activity levels of 137Cs radionuclide. 137Cs activity in the tested algae species and in soft parts of mussel and sea snail, were found to be below the lower limit of detection. On the other hand, the 137Cs concentration in muscle tissue of the sea snail samples were found from 6±2 to 19±7 Bq·kg–1 dry weight. The range of the 137Cs concentration in anchovy fish muscles were found between 4±2 – 10±5 Bq·kg–1 dry weight. The 137Cs concentration in the whiting fish muscle was found below the lower limit of detection. However, this activity found in shad fish muscle to be 25±10 Bq·kg–1 dry weight. The concentrationsof the 137Cs activity in the sediment samples proved that the eastern region of the Black Sea was affected by Chernobyl at a very high degree compared with the western part. The measured 238U, 232Th and 40K concentrations in sediment samples are within the range of the cited values in the previous works at the Turkish Black Sea coast.
Abstract
Moss samples collected from the eastern Black Sea about 6.5 years after the Chernobyl accident have been analyzed for radiocesium activity.134Cs activity was also detected in all the samples beside137Cs radionuclide. The levels of total cesium activity in the mosses proved that the coastal zone in the eastern Black Sea region was highly contaminated.
