The air-water distribution ratio K1, ether-water distribution ratio K2, and solubility in water were measured for 17 nitrosamines, 3 nitrosamides, and 1 nitrosocyanamide. For K1, air was analysed either by UV absorption of ethanol extracts or by gas chromatography. K1 at 37 degrees C varied from less than 2 X 10(-6) to 4.5 X 10(-3), with 11 compounds showing K1 greater than 10(-4). A literature analysis provided data on the carcinogenicity of these N-nitroso (NNO) compounds toward the esophagus, nose, and liver of the rat. This compilation of data on physical properties and carcinogenicity of NNO compounds was then analysed in terms of: a) safety of workers handling either solutions of volatile NNO compounds or animals treated with these compounds, b) analytic methdology, and c) possible correlations between K1-, K2-, and solubility-characteristics, and carcinogenicity. Overall correlations were not observed. However, within each of five chemical groups, K1 and K2 tended to be associated positively with esophageal and nasal carcinogenicity and negatively with hepatic carcinogenicity. Water solubility showed the opposite associations.

Recent studies in the cholecystectomized guinea pig( 1 ) , have shown that dehydrocho-§ Prepared acoording to the method of Crick, Hanper, and Raper by Boots Pure Drug

Agaritine (A), an ingredient of the cultivated mushroom of commerce Agaricus bisporus, was administered by subcutaneous injection to two groups of randomly bred Swiss mice. In the first group the animals of both sexes were treated at a 100 micrograms/g body weight basis five times at weekly intervals, while in the second group the mice received a single A treatment of 100 micrograms/g body weight for females and 50 micrograms/g body weight for males. The administration of the compound resulted in no detectable carcinogenic effect in the animals. Since some of the breakdown products of A were shown to be carcinogenic in mice and the mushroom itself was found to be mutagenic, the field is discussed in the light of the obtained results.

Administration of either Escherichia coli asparaginase or guinea pig serum to C3H/HE mice with the 6C3HED lymphosarcoma is followed by depression of glycine in the tumor. This decrease in cellular glycine concentration does not occur in a tumor resistant to asparaginase. The inhibition of the lymphosarcoma by asparaginase can be reversed by intraperitoneal injection of asparagine or glycine. This reversal appears to be specific because lysine, threonine, serine, and aspartic acid were ineffective. Loss of cellular glycine may be more important than loss of asparagine because of the requirement for glycine in purine synthesis.

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