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Abstract  

Neutron activation analysis was used to investigate and quantify the level of heavy metal uptake in the marine environment of Lake Austin in Austin, TX. Specifically, the samples studied were largemouth bass, or micropterus salmoides. The presence of heavy metals in the food chain presents multiple hazards, mostly as a food hazard for those species that ingest the fish, namely humans. To measure the concentrations of heavy metals in various fish samples, the nuclear analytical technique of neutron activation analysis (NAA) was used. Both epithermal and thermal irradiations were conducted for the NAA to look for short and long-lived radioisotopes, respectively. The samples themselves consisted of liver and tissue samples for each of the fish caught. Each sample was freeze-dried and homogenized before irradiation and spectrum acquisition. The results showed that all levels of heavy metals were not sufficient enough to make the fish unsafe for eating, with the highest levels being found for iron and zinc. Gold was found to be at much higher concentrations in the younger fish and virtually non-existent in the larger of the samples.

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Drasch, G., Wanghofer, E. and Roider, G. (1997): Are blood, urine, hair, and muscle valid biomonitors for the internal burden of men with the heavy metals mercury, lead and cadmium? Trace Elements and Electrolytes 14 , 116

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Abstract  

Results of determination of 137Cs, 90Sr, 40K, 239+240Pu, and heavy metals: Mn, Zn, Pb, Cd, Ni, Cr, Co, and Cu in skeletons of 15 species of birds of prey from Eastern Poland were presented. The greatest amounts of 137Cs and 90Sr (70 Bq/kg and 33 Bq/kg, respectively) were found in rough-legged buzzards (Buteo lagopus), winter visitors, coming from former soviet nuclear test places. Concentrations of 239+240Pu in raptors were negligible, only lesser-spotted eagles (Aquila pomarina) revealed slightly higher values. Median concentrations of 137Cs and 90Sr in raptors which feed predominantly on small mammals were higher in comparison to concentrations found in other ones preferring different trophy. The most noticeable was a very high lead concentration (reaching above 600 mg/kg) in birds which utilize un-retrieved hunting casualties as their prey.

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Abstract  

The sustainable development of agricultural waste is nowadays a main strategy in producing neutral CO2 energy and metal removal technologies. In Egypt, large amounts of rice straw are annually burnt in the open air causing severe air pollution that could be directed to co-firing and adsorption technologies. On bench scale, rice straw was positively contributed in a clean and smokeless co-firing process with methanol due to the oxidizing effect of the alcohol. The co-firing temperature control is vital to develop the adsorptive character of the residual ash and to avoid prolonged time needed to improve the physical properties of the rice straw if applied directly as a biosorbent. The consumed methanol in the process ranges from 0.15 to 0.3 liter per each kg of straw depending on its compaction. The grossed heat value from such process may drive steam generator for electricity. The residual ash was subsequently cross-linked in uranium and heavy metals adsorption tests from solutions. The porous texture of the residual ash and the amorphous nature of the silica along with potassium content provide a suitable condition for uranium immobilization especially if phosphorus or vanadium exist. The resulted chemical precipitate is analogues in composition to meta-ankoleite (KUO2PO4·3H2O) or hydrated carnotite (K2(UO2)2V2O8)·1-3H2O respectively. The XRD data of the latter form show an enhancement in crystallinity of the amorphous precipitate with the heated samples.

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Abstract  

Harbour activities such as loading, unloading and transport of materials may be an important source of Atmospheric Particulate Matter (APM). Depending on the materials, the type of operation and the meteorological conditions, these activities may have an impact on the levels of APM around harbour areas. The aim of this work was to characterize the emissions of dust providing from operations associated with phosphorite handling in harbours. Phosphorite is a non-detrital sedimentary rock which contains high amounts of phosphate bearing minerals and is used for the production of phosphorous based fertilizers. When handled in harbours frequently cause visual and environment impacts due to its physical and chemical characteristics. The techniques Instrumental Neutron Activation Analysis and Particle Induced X-ray Emission were applied as sensitive analytical tools for the determination of heavy metals and rare earth elements in phosphorite and in the APM sampled in the harbour during the unloading operations. Results showed that manipulation of phosphorite during harbour operations resulted in high emissions of particles, principally from the coarse fraction. These emissions were enriched in rare earth elements and heavy metals and were very affected by the provenience of the phosphorite.

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Abstract  

In 2002, an extensive study was performed in forest sites of Izmir. This first study results led on the one hand, to quantify of 137Cs and 40K concentration in mushrooms collected in the Izmir region and to a first evaluation of dose in people due to the ingestion of radionuclide-contaminated mushrooms. The mushroom concentration values varied over a wide range from below detection limit to 401 ± 4 Bq kg−1 (dry wt) for 137Cs. The 40K concentration values obtained for different species of mushrooms ranged from 588 ± 26 Bq kg−1 to 2024 ± 63 Bq kg−1 (dry wt). The annual effective dose values due to mushroom ingestion for 137Cs are lower than the ICRP-2007’s reference level value of 1 mSv for “existing” exposure situation. Inductively coupled plasma-mass spectrometry was used to measure many alkali–alkaline earth elements and heavy metals in mushroom samples. The relationships among the concentrations of 137Cs and the stable elements were presented and the occurrence of metals in mushrooms was evaluated.

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Interventional Medicine and Applied Science
Authors: Alexey Tymoshenko, Gennadii Tkach, Vitalii Sikora, Valentina Bumeister, Ihor Shpetnyi, Mykola Lyndin, Olena Maksymova, and Anna Maslenko

effect on all biological species [1] . Direct or indirect intake of different contaminants can cause a disease or become a reason for the development of related disorders [2, 3] . Heavy metals are considered to be terribly dangerous for their

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Abstract  

The present work is devoted to an investigation on the soil to mushroom transfer parameters for 137Cs and 40K radionuclides, as well as for some stable elements and heavy metals. The results of transfer factors for 137Cs and 40K were within the range of 0.06–3.15 and 0.67–5.68, respectively and the most efficiently transferred radionuclide was 40K. The TF values for 137Cs typically conformed to a lognormal distribution, while for 40K showed normal distribution. Statistically significant correlations between 137Cs soil to mushroom transfer factors and agrochemical soil properties have been revealed. Although the concentration ratios varied within the species, the most efficiently transferred elements seems to have been K, followed by Rb, Zn, Cu, Cd, S, Cs and Hg.

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. , Finlay , R. , Botton , B. and Chalot , M. ( 2000 ): Differential responses of ectomycorrhizal fungi to heavy metals in vitro . – Mycol. Res. 104 : 1366 – 1371 . http://dx.doi.org/10.1017/s0953756200003166

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Adriano, D. C., 1986. Trace Element in the Terrestrial Environment. Springer-Verlag. New York. Alapi, K. & Győri, Z., 2003. Investigations on mud on heavy metal

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