The heteropolyanions [Bi 2 W 22 O 74 (OH) 2 ] 12-(1) and [X 2 W 20 M 2 O 70 (H 2 O) 6 ] (14-2n)-(X ) Sb 3+ , Bi 3+ ; M n+ ) Fe 3+ , Co 2+ , Zn 2+ ) (2-7) have been synthesized as alkali metal and ammonium salts, respectively, and characterized by elemental analysis, infrared spectroscopy, and X-ray crystallography. These tungsto bismutates and antimonates reveal one common feature: the trivacant -B-XW 9 O 33 Keggin fragment as the structural building unit. Formally, the unit can be derived from the Keggin structure by removing one trimetalate fragment, W 3 O 13 , and a 60°rotation of one of the remaining W 3 O 13 subunits around the X-O W3X bond vector (the subscript indicates the element(s) bonded). The unshared pair of electrons of the respective central, pyramidally coordinated heteroatom Sb III or Bi III prevents formation of the complete spherical structure. In the presented heteropolyanions 1-7, two -B-XW 9 O 33 units are connected by two WO 2 groups. Further stabilization of this hitherto unknown bis-decatungsto ion [X 2 W 20 O 70 ] 14-is reached either by addition of two formal fac-WO 3 anti-Lipscomb's rule units to give the bis-undecatungsto bismutate [Bi 2 W 22 O 74 (OH) 2 ] 12-(1) or by addition of two M n+ (H 2 O) 3 groups (M n+ ) Fe 3+ , Co 2+ , Zn 2+ ) forming the large, transition-metal-substituted heteropolyanion clusters [X 2 W 20 M 2 O 70 (H 2 O) 6 ] (14-2n)-(X ) Sb 3+ , Bi 3+ ; M n+ ) Fe 3+ , Co 2+ , Zn 2+ ) (2-7).

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Information about heavy metal concentrations in food products and their dietary intake are essential for assessing the health risk of local inhabitants. The main purposes of the present study were (1) to investigate the concentrations of Zn, Cu, Pb, and Cd in several vegetables and fruits cultivated in Baia Mare mining area (Romania); (2) to assess the human health risk associated with the ingestion of contaminated vegetables and fruits by calculating the daily intake rate (DIR) and the target hazard quotient (THQ); and (3) to establish some recommendations on human diet in order to assure an improvement in food safety. The concentration order of heavy metals in the analyzed vegetable and fruit samples was Zn > Cu > Pb > Cd. The results showed the heavy metals are more likely to accumulate in vegetables (10.8-630.6 mg/kg dw for Zn, 1.4-196.6 mg/kg dw for Cu, 0.2-155.7 mg/kg dw for Pb, and 0.03-6.61 mg/kg dw for Cd) than in fruits (4.9-55.9 mg/kg dw for Zn, 1.9-24.7 mg/kg dw for Cu, 0.04-8.82 mg/kg dw for Pb, and 0.01-0.81 mg/kg dw for Cd). Parsley, kohlrabi, and lettuce proved to be high heavy metal accumulators. By calculating DIR and THQ, the data indicated that consumption of parsley, kohlrabi, and lettuce from the area on a regular basis may pose high potential health risks to local inhabitants, especially in the area located close to non-ferrous metallurgical plants (Romplumb SA and Cuprom SA) and close to Tăuții de Sus tailings ponds. The DIR for Zn (85.3-231.6 μg/day kg body weight) and Cu (25.0-44.6 μg/day kg body weight) were higher in rural areas, while for Pb (0.6-3.1 μg/day kg body weight) and Cd (0.22-0.82 μg/day kg body weight), the DIR were higher in urban areas, close to the non-ferrous metallurgical plants SC Romplumb SA and SC Cuprom SA. The THQ for Zn, Cu, Pb, and Cd was higher than 5 for <1, <1, 12, and 6% of samples which indicates that those consumers may experience major health risks.

Two tris(oxouranium)-substituted Keggin and Dawson sandwich-type tungstophosphate heteropolyanions NaI2[(UO)3(H20)6(PW9034)2]21 H20 (1) and Nalsl(UO)3(H20)6(PEW15056)2]'27 H20 (2) have been prepared by reaction of uranium sulphate with [PW9034] 9-and [P2W15056] 12-, respectively, in aqueous media at 4.7 pH. The products were characterized by elemental and thermal analyses, IR, UV-Vis spectroscopy and magnetical susceptibility. The results of these studies suggest that the compounds obtained from Keggin and Dawson trilacunary anions are 2:3 sandwich-type complexes and both exhibit a square antiprismatic stereochemistry for uranium(IV) with retention of polyoxometallate parent structure.

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