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1.
J Environ Radioact ; 149: 1-7, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26186235

RESUMO

Activity concentrations of (137)Cs, (40)K, (210)Po, (210)Pb, (234)U and (238)U were determined in umbrella and oral arms of three widely distributed jellyfish species; namely Rhopilema nomadica Galil, 1990, Aurelia aurita Linne, 1758 and Aequorea forskalea Péron & Lesueur, 1810 collected from February 2011 to January 2012 in four sampling locations along the Syrian coast (Eastern Mediterranean Sea). The results have shown significant variations in radionuclides activity concentrations amongst the species. The average activity concentrations of (40)K, (210)Po, (210)Pb, (234)U and (238)U in the umbrella of R. nomadica species were higher than the average activity concentrations in the umbrella of A. aurita species by about 3.2, 1.4, 1.8, 3.2 and 3.2 folds, and A. forskalea species by about 45.5, 15.4, 19, 7.4 and 7.6 folds, respectively. The average activity concentrations of (40)K, (210)Po, (210)Pb, (234)U and (238)U in oral arms of R. nomadica species were higher than the average activity concentrations in oral arms of A. aurita species by about 3.8, 1.7, 1.9, 2.8 and 2.9 folds, respectively. (137)Cs activity concentrations were below the detection limit in all measured samples. In addition, activity concentrations of (137)Cs, (40)K, (210)Po, (210)Pb, (234)U and (238)U were also determined in 44 surface seawater samples and the activity concentrations ranged between 10.6 and 11.9 Bq l(-1) for (40)K, 1.1 and 1.4 mBq l(-1) for (210)Po, 0.5 and 0.7 mBq l(-1) for (210)Pb, 40.8 and 44.5 mBq l(-1) for (234)U, and 36.9 and 38.4 mBq l(-1) for (238)U, while (137)Cs activity concentrations were below the detection limit in all measured samples. Moreover, the umbrella and oral arms readily accumulated (40)K, (210)Po, (210)Pb, (234)U and (238)U above ambient seawater levels in the sequence of (210)Po > (210)Pb > (4) K > (234)U and (238)U. Concentration ratio (CR) values were relatively high for (210)Po and (210)Pb and reached 10(3) and 10(2), respectively for the jellyfish R. nomadica species compared to A. aurita and A. forskalea species. Therefore, R. nomadica can be used as biomonitor for these two radionuclides in the Eastern Mediterranean Sea. However, the obtained data can be considered the first reported baseline values for radioactivity in jellyfish.


Assuntos
Hidrozoários/metabolismo , Monitoramento de Radiação , Radioisótopos/metabolismo , Cifozoários/metabolismo , Poluentes Radioativos da Água/metabolismo , Animais , Mar Mediterrâneo , Síria
2.
Bull Environ Contam Toxicol ; 93(3): 370-4, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25063371

RESUMO

This paper presents measurements of cesium 137 ((137)Cs) in the Syrian environment during the period between 2006 and 2010. More than 1,000 samples of soil, water, plants and aquatic life were collected from different locations. The measurements were realized using gamma spectroscopy, and the results showed that radioactivity concentrations were low overall. Concentrations ranged from below detection limits to several tens Bq kg(-1) (dry matter) or 9.8 mBq L(-1) (water), which were well below maximum allowable levels in food or drinking water as established according to Syrian national standards or the WHO/FAO Codex guidelines. However, high (137)Cs activity levels were observed in soil samples collected at a high elevation (Kadmous highs), where a mean concentration of 1,900 Bq kg(-1) was obtained.


Assuntos
Radioisótopos de Césio/análise , Poluentes Radioativos do Solo/análise , Poluentes Radioativos da Água/análise , Produtos Agrícolas/química , Monitoramento Ambiental , Água Doce/química , Poaceae/química , Solo/química , Síria
3.
J Environ Radioact ; 67(2): 157-68, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12660047

RESUMO

Three types of sea alga distributed along the Syrian coast have been collected and analyzed for radioactivity and trace elements. Results have shown that (137)Cs concentrations in all the analyzed sample were relatively low (less than 1.2 Bq kg(-1) dry weight) while the levels of naturally occurring radionuclides, such as (210)Po and (210)Pb, were found to be high in most samples; the highest observed value (27.43 Bq kg(-1) dry weight) for (210)Po being in the red Jania longifurca alga. In addition, most brown alga species were also found to accumulate (210)Po, which indicates their selectivity to this isotope. On the other hand, brown alga (Cystoseira and Sargassum Vulgare) have shown a clear selectivity for some trace metals such as Cr, As, Cu and Co, this selectivity may encourage their use as biomonitor for pollution by trace metals. Moreover, the red alga species were found to contain the highest levels of Mg while the brown alga species were found to concentrate Fe, Mn, Na and K and nonmetals such as Cl, I and Br.


Assuntos
Metais Pesados/análise , Phaeophyceae/metabolismo , Poluentes Químicos da Água/análise , Poluentes Radioativos da Água/análise , Radioisótopos de Césio/análise , Monitoramento Ambiental , Humanos , Radioisótopos de Chumbo/análise , Mar Mediterrâneo , Síria
4.
J Environ Radioact ; 58(1): 35-44, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11763102

RESUMO

The impact of loading cargoes of phosphate ore into ships on the near marine environment at the Syrian coast has been evaluated. Results have shown a significant enhancement of 210Po, 210Pb and other natural radionuclides in sediment and surface water inside the port area. The highest 210Po and 210Pb concentrations observed in sediment were found to be 170 and 64 Bq kg(-1) respectively, while 210Pb and 210Po concentrations in surface water ranged from 5 to 20 mBq l(-1) and 0.93 to 3.23 mBq l(-1). In addition, comparable values of 210Po and 210Pb for all marine organisms (algae, crab and fish) suggest that their use as indicators for phosphate pollution is not recommended. However, the effect of loading cargoes on the port marine environment of Tartous was found to be mainly related to wind direction where radioactive air particulate are either being dispersed to land or sea.


Assuntos
Indústria Química , Radioisótopos de Chumbo/análise , Fosfatos/química , Polônio/análise , Meios de Transporte , Poluentes Radioativos da Água/análise , Animais , Braquiúros/química , Eucariotos/química , Peixes , Humanos , Radioisótopos de Chumbo/química , Polônio/química , Síria , Movimentos da Água , Vento
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