Institut fur Organische Katalyseforschung an der Universitat Rostock e.V., Buchbinderstrasse 5-6, 18055 Rostock, Germany.

The rhodium-catalyzed amination of aromatic olefins and the palladium-catalyzed amidocarbonylation of aldehydes are presented as new atom-efficient methods to yield biologically interesting amines and N-acyl amino acids. Copyright 1999 John Wiley & Sons, Inc. Med Res Rev, 19, No. 5, 357-369, 1999

PMID: 10502740, UI: 99434380

Int Arch Occup Environ Health 1996;69(1):33-8

Cyto- and genotoxic effects of coordination complexes of platinum, palladium and rhodium in vitro.

Bunger J, Stork J, Stalder K

Department of Occupational and Social Medicine, Georg-August University Gottingen, Germany.

The growing industrial use of platinum group elements as catalysts, especially in automobile exhaust detoxification (trimetal catalytic converters), is causing increasing occupational and environmental pollution. The cytotoxic and mutagenic properties of industrially used coordination complexes of platinum, palladium and rhodium were investigated using the neutral red cytotoxicity assay on two established cell lines and the Salmonella typhimurium/microsome test system (Ames test). Cytotoxic effects of the platinum complexes, measured as ED50, occurred at test concentrations of 0.2 mM. The analogous palladium salts tested were 3 times less toxic with ED50 being 0.6 mM, while the rhodium salts proved to be 30 times less toxic (ED50 = 6 mM). Levels of toxicity of the different complexes of a particular metal did not differ significantly from each other, which indicates that the metal itself is responsible for the toxic effects. In the Ames test, the spontaneous mutation rates increased by factors of 3 to 20 when the four tester strains were exposed to the platinum complexes. The analogous rhodium compounds proved to be considerably less mutagenic, and palladium demonstrated no mutagenic potential. As all of the four tester strains contain different mutations, the mutagenic potential of platinum and rhodium complexes appears to be based on a variety of mechanisms that damage DNA. From these in vitro experiments, it can be concluded that water-soluble complex salts of rhodium are less toxic and have a smaller mutagenic potential than the analogous platinum complexes. For palladium there is no evidence of any mutagenic property. From this point of view, the development of a catalytic converter containing predominantly palladium may be a possible means of minimizing potential health risks from this exhaust detoxification technique.

PMID: 9017432, UI: 97169889

J Nutr 1975 Dec;105(12):1607-19

Nickel deficiency and nickel-rhodium interaction in chicks.

Nielsen FH, Myron DR, Givand SH, Ollerich DA

Nickel deficiency was produced in chicks under near optimal growth conditions. This judgment is based on the finding that chicks fed the experimental diet supplemented with nickel had a very satisfactory growth rate, over 600 g in 4 weeks. To induce nickel deficiency, chicks were raised in plastic cages located inside plastic isolators and were fed diets (containing 2-15 ng of nickel/g) based on dried skim milk, acid-washed ground corn, EDTA-extracted soy protein, and corn oil. In 2 experiments, controls were fed 3 mug of nickel/g as NiCl2-6H2O. In experiment 3, instead of 1 control group 25, 50, 250, and 2,500 ng/g of supplemental dietary nickel as NiCl2-6H2O were each given to separate groups of chicks. Nickel deprivation resulted in: ultrastructural changes in the liver with the most obvious abnormality in the organization of the rough endoplasmic reticulum; altered gross appearance, reduced oxidative ability, and decreased lipid phosphorus in the liver; altered shank skin pigmentation that was associated with a decrease in yellow lipochrome pigments; and lower hematocrits. Deficiency also tended to increase the thickness of the legs and size of the hock; decrease the length:width ratios of the tibias and femurs; and decrease the plasma cholesterol. None of the signs of deficiency were seen in chicks fed diets containing at least 52 ng of nickel/g. In one experiment, a group of birds was fed 50 mug of rhodium/g of diet as (ClRh(NH3)5)SO4 to ascertain whether rhodium is a metabolic antagonist of nickel. Supplemental rhodium increased the hematocrits and liver oxidative ability of both nickel-deficient and -supplemented chicks, and increased total liver lipids, liver lipid phosphorus, and liver cholesterol in the nickel-deficient chicks alone. Rhodium did not increase the signs of nickel deficiency.

PMID: 1195022, UI: 76071236