No abstract

275ChemInform Abstract The properties of the bimetallic complexes, where the only variation is the energy of the bridging ligand's π system, are studied. The lowest energy electronic absorption band is assigned as a MLCT process, where the acceptor state is localized primarily on the bridging ligand. Unlike the Ru complexes analogous to (IVa) and (IVb), the bimetallic Re containing complexes show no luminescence. The complexes (III) and (IV) display two reductions and one oxidation. The second reduction may be due to a metal-centered Re(I)/Re(0) process for (IIIa) and ligand centered for (IIIb) and (IIIc). A third reduction is observed for (IVa) and (IVb). A comparison with the analogous Ru complexes show that the Re(CO)3Cl moiety is more effective in stabilizing the reduced forms of the heterocyclic ligands than (Ru(bipy)2)2+ (yields not given).

No abstract

No abstract

An observational biomonitoring study was conducted involving adults and children in households that purchased and applied a cyphenothrin-containing spot-on product for dogs as part of their normal pet care practices. The 3- to 6-yr-old children had greater exposure than the adult applicators in the same house, 3.8 and 0.6 μg/kg body weight, respectively. The mean measured values in children were 13-fold lower than those estimated using the U.S. Environmental Protection Agency (EPA) current standard operating procedures (SOP) for pet products (assuming 5% dermal absorption), although the maximum absorbed dosage of one child on one day was equivalent to the default value derived from the SOPs. With regard to potential human health risks, it can be concluded that despite the inherent conservatism in both the exposure and toxicology data, the margins of exposure (MOE) were consistently greater than 100 for average, 95th percentile, and maximum exposures. More specifically, the results of this study demonstrated that the MOE were consistently greater than 1,000 for mean exposures and exceeded 100 for 95th percentile and maximum measured exposures, which clearly indicates a reasonable certainty of no harm when using the cyphenothrin spot-on products. It is also noteworthy that Sergeant's spot-on products containing cyphenothrin currently sold in the United States have lower weight percentages of active ingredient and lower applied amounts than those used by all but two of the participant households in this study.