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How to decontaminate liquid biohazard waste WITHOUT bleach? (contains guanidine - (Dec/08/2011 )

I will soon do some DNA extractions from human blood, with a procedure that involves buffers containing guanidine thiocyanate. I figure that the waste after the procedure will contain the blood with potential biohazards AND guanidine thiocyanate.

Usually I decontaminate liquid biohazard waste with bleach, however bleach can't be mixed with the guanidine thiocyanate. How can I decontaminate the biohazards in the waste so I can dispose it as chemical waste?

I feel like this must be a common thing since there are plenty of extraction kits that use guanidine thiocyanate. But the company couldn't recommend any bleach alternatives and I have not found anything online.


The guanidine is a chaotrope - it is very very likely to kill anything living (or viral or prion) in the extraction process. However, you could autoclave or incinerate the waste, you would need an approved unit for each method however.


I agree it is likely to kill everything, but I am trying to comply with regulations for disposing it properly. I can't find any EPA-registered disinfectants for bloodborne pathogens that contain guanidine thiocyanate. I am looking here

I'm sure someone has had to do this since so many kits use guanidine thiocyanate.


Do you have a biosafety officer where you work/study? They should be the person you contact, as it is their job to know the answer to these types of questions.




Virkon would probably oxidise the guanidine in the same manner as bleach, but I don't think it would release Cl gas like bleach would.