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Kamanjah over at Right to vape found this document on NASA's look at using Propylene Glycol as a coolent and their investigations into it's toxicology.
Spacecraft Maximum Allowable Concentrations for Selected Airborne Contaminants: Volume 5
Pretty interesting read, or the bits i could understand were.
	
		
			
		
		
	
			
			Kamanjah over at Right to vape found this document on NASA's look at using Propylene Glycol as a coolent and their investigations into it's toxicology.
Spacecraft Maximum Allowable Concentrations for Selected Airborne Contaminants: Volume 5
Pretty interesting read, or the bits i could understand were.
				
		