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The aim of this study is to investigate the trace elements (TE) contents of potential biomonitors in a historical Zn-Pb mining district: apiary products (honey, royal-jelly and beeswax) lichen and moss were sampled and analysed. In spite of high TE concentrations in mining waste and soil, apiary products are free of TE contamination originating from historical mining. Lichen/moss show high TE levels, which suggest atmospheric input of local dust. Pb isotopes analysis proved the origin of TE found in lichen/moss to be mainly mining waste. These results help discuss the choice of relevant organisms for monitoring TE in the environment and bring additional data on the potential impacts of brownfields left after mining, especially on food products from apiaries.

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The trace-elements (TE) contents of honey, royal-jelly and beeswax from a historical Zn-Pb mining district have been investigated to assess potential contamination. In spite of high levels of heavy metal (As, Cd, Tl, Pb) in wastes left after mining stopped, apiary products appear to be relatively free of TE contamination. For honey, the following average levels (±standard error) were observed: Zn 571±440μgkg(-1), Pb 26±20μgkg(-1), Tl 13±10μgkg(-1), Cd 7±6μgkg(-1) and As 3±4μg.kg(-1). These results bring additional data to the potential impact of brownfields left after mining on apiary products. They also bring new data to assess potential risks linked with honey consumption and discuss legal TE contents in honey and other food products from apiaries.

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ring closure reactions ring closure reactions O 0130 23 -038 β-and γ-Lactams by Nickel Powder Mediated 4-exo or 5-endo Radical Cyclizations. A Concise Construction of the Mesembrine Skeleton. -N-alkenyl trichloroacetamides undergo under the title conditions reversible 4-exo radical cyclization. The cyclized radical is trapped in different ways leading to β-lactams. When the trap is omitted or not efficient enough, unusual irreversible 5-endo cyclization occurs affording functionalized five-membered lactams. The synthesis of bicyclic γ-lactams provides access to the sceletium alkaloids skeleton. -(CASSAYRE, J.; QUICLET-SIRE, B.; SAUNIER, J.-B.; ZARD, S. Z.; Tetrahedron 54 (1998) 7, 1029-1040; Inst. Chim. Subst. Nat., CNRS, F-91198 Gif-sur-Yvette, Fr.; EN)