Concentrations of Metals, Metalloids, and Chlorinated Pollutants in Blood and Plasma of White Stork (Ciconia ciconia) Nestlings From Spain.

The aim of this study was to determine the levels of different inorganic elements (lead [Pb], mercury [Hg], and arsenic [As]) and persistent chlorinated pollutants (including polychlorinated biphenyls [PCBs] and organochlorine pesticides [OCPs]) in blood and plasma of White stork (Ciconia ciconia) nestlings from northwest (NW) Spain. The concentrations of PCBs were lower than the limit of detection in all samples. The OCPs γ-HCH, 4,4'-DDE, HCB, and endosulfan were detected most frequently in plasma from White stork nestlings. These OCPs were detected in 98, 54, 39, and 37 % of all samples, respectively. However, the concentrations of organic pollutants were lower than the risk thresholds for birds. The mean levels of the inorganic elements Pb, Hg, and As were found to be 36.92 ± 33.48, 16.48 ± 12.87, and 9.813 ± 13.84 µg/L, respectively. These levels were also lower than the risk thresholds for birds. This study not only provides a snapshot of the levels of both inorganic and organic contaminants in wild White storks in NW Spain, it also provides a useful baseline for biomonitoring levels of the measured contaminants in this area.

Non-destructive multibiomarker approach in European quail (Coturnix coturnix coturnix) exposed to the herbicide atrazine.

The effect of orally administered atrazine (25 or 100 mg/kg on days 0, 5, and 10 of the experiment) was studied in European quail (Coturnix coturnix coturnix) on four non-destructive biomarkers: fecal porphyrins, blood glutathione-S-transferase, glutathione reductase, reduced glutathione, and malondialdehyde (MDA). Uroporphyrin I (UPI) and coproporphyrins I and III (CPIII) were the main porphyrins detected in feces. The lowest dose of ATZ caused a significant (P < 0.05) increase in UPI and CPIII at day 5, and the highest dose of ATZ caused an induction of CPI and a significant (P < 0.05) decrease in MDA levels at day 30.

Synthesis, structure, and magnetic properties of three new one-dimensional nickel(II) complexes: new magnetic model for the first one-dimensional S = 1 complex with alternating ferro-ferromagnetic coupling.

Three new one-dimensional nickel(II) complexes with the formulas trans-[Ni(N-Eten)2(mu1.3-N3)]n(ClO4)n (1), trans-[Ni(N-Eten)2(mu1.3-N3)]n(PF6)n (2), and cis-[Ni(N-Eten)(mu1.1-N3)2]n (3) (N-Eten = N-Ethylethylenediamine) were synthesized and characterized. Complex 1 has the P2(1)/c space group and consists of a structurally and magnetically alternating one-dimensional antiferromagnetic system with end-to-end azido bridges. Compound 2 has the P1 space group and has alternate units in its structure but consists of a magnetically uniform one-dimensional antiferromagnetic system with end-to-end azido bridges. Complex 3 has the I2/a space group and may be described as a structurally and magnetically alternating one-dimensional ferromagnetic system with double azido bridged ligands in an end-on coordination mode. The chi(M)T versus T plots for compound 3 suggest an intramolecular ferromagnetic interaction between adjacent NiII ions and metamagnetism at low temperature (below 10 K). The magnetization measurements versus applied field confirm this metamagnetic ordering. In order to describe the magnetic data of this compound we developed a general formula for the magnetic susceptibility of the isotropic ferro-ferromagnetic S = 1 Heisenberg chain in terms of the alternation parameter alpha (= J2/J1); this assumed a variation of chi(M)T versus the length N.

A Metamagnetic Two-Dimensional Molecular Material with Nickel(II) and Azide.

Bridging azido ligands transmit both ferro- and antiferromagnetic interactions. The sheetlike structured complex [Ni(µ-N(3))(2)(N,N-Et(2)-N'-Me-en)](n) (see picture) exhibits a range of magnetic behaviors at low temperature. Short-range ferromagnetic and three-dimensional antiferromagnetic ordering compete, giving metamagnetic behaviors. N,N-Et(2)-N'-Me-en=N,N-diethyl-N'-methylethylenediamine.

Synthesis, structure, and magnetic properties of two new ferromagnetic/antiferromagnetic one-dimensional nickel(II) complexes. Magnetostructural correlations.

Two new one-dimensional nickel(II) complexes were synthesized and characterized: [Ni(N,N-dimethylethylenediamine)(N3)2] (1) and [Ni(2-aminoethylpyridine)(N3)2] (2). The crystal structures of 1 and 2 were solved. Complex 1 crystallizes in the monoclinic system, space group P2(1)/n with a = 10.569(2) A, b = 7.331(4) A, c = 12.9072(8) A, beta = 111.324(10) degrees, and Z = 4. Complex 2 crystallizes in the monoclinic system, space group P2(1)/c with a = 12.299(5) A, b = 14.307(2) A, c = 12.604(3), beta = 106.72(2) degrees, and Z = 4. The two complexes are similar and may be described as one-dimensional systems with double-azido-bridged ligands in end-to-end and end-on coordination alternatively. The end-on moiety is almost identical for 1 and 2, but the end-to-end moiety is different in each structure: for 1 this part is almost planar but for 2 is nonplanar. In both cases the Ni atoms are situated in similar distorted octahedral environments. The magnetic properties of the two compounds were studied by susceptibility measurements vs temperature. The chi M vs T plots for 1 and 2 show a global antiferromagnetic behavior with a maximum near room temperature for 1 and at very low temperature for 2. J values for 1 and 2 were deduced from the spin Hamiltonian -sigma(J1SiSi+1 + J2Si+1Si+2). The computational method was based on the numerical solution for finite systems of increasing size. J values for 1 were J1 = -187 cm-1 and J2 = +77 cm-1 and for 2 J1 = -28 cm-1 and J2 = +73 cm-1. The positive values correspond to end-on azido ligands and the negative values to end-to-end azido ligands. Since the geometries of the [Ni(N3)]2 moieties involving the end-on azido ligands are almost the same in the two structures, the ferromagnetic coupling is nearly identical in the two compounds, while the significantly different antiferromagnetic couplings reflect the near planarity of the end-to-end Ni2(N3)2 fragment in 1 and its twisted geometry in 2.