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Astat w chemii i medycynie

100%

Pruszyński M. , Bilewicz A.

tom [Z] 58, 5-6

403--425

Astatine, element 85, is the heaviest halogen. The first synthesis of' 211At was performed by Corson by irradiation of 209Bi target with a-particles. Most of the chemical studies have been done using this isotope. Astatine is one of the most difficult clements to study from a chemical point of view, and our knowledge of its compounds is rather incomplete compared to what we know about other elements. For this there are several reasons, especially that the astatine have very short-lived isotopes which make it impractical to obtain weighable amounts of the element. Therefore, chemical studies of astatine can be performed only with very low concentrations - concentrations much less than the impurity levels commonly present in an experimental system. Radionuclide 211At has been newly discovered within development of nuclear medicine, because it has a lot of diserable and advantageous properties, that are required in cancer therapy. It's potential application was recognized due to the radiotoxicity associated with emission of a particle and that of its daughter 211Po. This review presents current knowledge about chemistry of astatine, especially its inorganic chemistry (e.g. valence states, anionic complexes of astatine with halogenides and pseudohalogenides ions etc.). Moreover, information is given about synthesis of some organic compounds of astatine. Special attention was paid on labelling of biologically active molecules with 211At and their potential applications in nuclear medicine.

Zawartosc metali ciezkich w tkankach swin z rejonu oddzialywania przemyslu miedziowego

58%

Kolacz R. , Dobrzanski Z. , Kroliczewska B. , Kolodziej P.

2000

tom 27

nr 1

341-349

Zawartość wybranych pierwiastków toksycznych w produktach pszczelich

58%

Madras-Majewska B. , Jasinski Z. , Zajdel B. , Gabka J. , Ochnio M. , Petryka W. , Kaminski Z. , Sciegosz J.

tom 82

nr 3

The development of industry, intensive agriculture and the automotive industry has contributed to a massive increase in pollution of the environment. The many pollutants accumulating in the environment include toxic elements (Hg, Zn, Cu, Pb, As, Cd) whose natural content in soil and the atmosphere is very small. Honeybees (Apis mellifera L.) are entirely dependent on flowering plants that provide them with nectar and pollen. They also make use of plant buds, from which they collect propolis. Therefore, since 1998 in the Apiculture Department of the Faculty of Animal Science research has been conducted on the content of heavy metals in bee products from all over Poland (108 apiaries, 324 colonies). The content of mercury and lead in propolis, honey and beebread was analysed. The results obtained were satisfactory, as the average mercury content (0.00027 mg/kg) and lead content (0.0485 mg/kg) of honey was low and did not exceed accepted norms in any of the samples tested. Moreover, the average content of mercury (0.00091 mg/kg) and lead (0.2885 mg/kg) in the beebread did not exceed the norms in any of the samples. The only product in which the average content of mercury (0.00491 mg/kg) and lead (9.6621 mg/kg) exceeded the norm was propolis. The results show that in most areas of Poland there is no danger of contamination of bee products with mercury and lead. Our findings and a review of the results of other authors clearly indicate that bee products such as propolis, honey and beebread can be used as bioindicators of environmental pollutants such as heavy metals.