Gas Aerosol Treatment

This method was first used by Auerbach when she investigated the mutagenicity of mustard gas. The advantage of this method is the rapid diffusion of the agent into living tissues. The treatment dose can be controlled precisely by regulating gas concentration and duration of treatment. 

By treating newly deposited eggs with CO2 gas, Tazima and Ohnuma found that CO2 was effective for the induction of androgenesis and gynogenesis, as well as polyploidy. They exposed eggs from wild-type females, which had been mated to double recessive pe re males, to CO2 gas shortly after deposition. 

Studies with nitrogen carried out in the same way were completely ineffective. 

The degree of the mutation response to chemical compounds depends on several factors. The mutation curve rises with increasing dose, reaches a plateau at a certain dose (concentration), and then falls off. But what we actually found after treatment with various compounds was not simple due to the interaction of a number of variables. Major variables are dose of chemical, developmental stage of germ cells, metabolic activation of the chemical, and others. Since observed mutation frequencies are the product of interaction among all these factors, they vary more or less from experiment to experiment. 

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