Toxicity of organolead compounds

Seinen W, Vos JG, van Spanje I, Snoek M, Brands R, Hooykaas H (1977a) Toxicity of organotin compounds. II. Comparative in vivo and in vitro studies with various organotin and organolead compounds in different animal species with special emphasis on lymphocyte cytotoxicity. Toxicology and Applied Pharmacology, 42(1) 197-212. 

The major organolead compounds found in the environment are the tetraalkyllead compounds and their di- and trialkyl decomposition products. Elevated levels of tetraalkyl-leads have two possible sources either (i) anthropogenic leaded petroleum inputs or (ii) environmental methylation of natural lead compounds. While the former is well established, the latter is the subject of some controversy in the literature. Interest in the environmental methylation process derives from the increased toxicity of methyllead compounds compared to their inorganic analogs. 

In what sense are the toxicities and environmental effects of organolead compounds particularly noteworthy ... 

Practical use of organolead compounds will be hardly extended due to their high toxicity and the possibility of sustainable pollution of the environment by the lead compounds. In this connection it must be indicated that the production of tetraethyllead, which achieved 270,000 tons by 1964 only in the USA, started to be reduced at the end of the 20th century. 

Hypervalent compounds are common in the case of lead, rather than the tetrahedral ones ". However, the coordination chemistry of hypervalent lead compounds has been much less studied than that of hypervalent organotin compounds, probably due to the well-known high toxicity of organolead derivatives. The progressive lowering of the three-center interaction for the group 14 column of the Periodic Table and the marked drop for lead can be accounted for in terms of the relativistic effect. ... 

The harmful effects of organolead compounds are considered to be much greater than those of inorganic lead. The toxicity of aUcyllead species diminishes in the sequence R4Pb R3Pb" — ... 

McClain, R. M. and Becker, B. A. (1972). Effects of organolead compounds on rat embryonic and fetal development Toxicol. Appl. Pharmacol., 21, 265 McClain, R. M. and Becker, B. A. (1975). Teratogenicity, fetal toxicity and placental transfer of lead nitrate in rats. Toxicol. Appl. Pharmacol., 31, 72 McConnell, P. and Berry, M. (1978). The effects of undernutrition on Purkinje cell dendritic growth in the rat. J. Comp. Neurol., Yll 159 McConnell, P. and Berry, M. (1979). The effects of postnatal lead exposure on Purkinje cell dendritic development in the rat. Neuropathol. Appl. Neurobiol., 5, 115... 

Organolead compounds are pollutants in air, water, soil, and sediments. The toxicity of organolead species depends on the organic groups bound to the Pb atom. Lead has four stable isotopes ( Pb, Pb, Pb, and Pb) and isotopic analysis of Pb can be used for geological dating and to track environmental processes and sources of Pb species. 

Because of their toxicity, all organolead compounds should be handled in well-ventilated fume-hoods. Workers should wear rubber gloves. Residues should not be thrown down sinks. 

The use of organolead compounds as paint biocides was also widely recognized, but tiiese lost out to the less toxic and better accepted organotin monomers and polymers. ... 

A book on biological effects of organolead compounds comprises a series of reviews on physiological properties and toxicity of Pb(C2H5)4 [438]. 

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