Contaminated Carbon Dioxide Cylinder

  • Saturday, September 08, 2018 6:32 PM
    Message # 6660513

     This is a first for me but I thought it was important enough to share. Recently in doing a repair on a carbon dioxide manifold we noticed a strong lavender odor coming from the regulators. To make a long story short  after having the gas tested and analyzed it was discovered that the carbon dioxide cylinder contained hemp oil.

     After more research it was discovered that the  USP CO2 cylinder was used in the extraction of cannabis to produce hemp oil.  If anyone is interested I can elaborate on all of this. The reason for this post is to let people be aware that people are using USP CO2 cylinders in the production of hemp oil.

     Two other points of interest is we discovered that this is not the first time this has occurred. Gas suppliers do not want general public to know that this has occurred more frequently of late especially with the Internet explaining how to do it.  We also thought it was isolated to Hawaii but discovered that the cylinder came from Texas. 

     Remember medical gases have no older and it’s not just trusting the label that reads USP. 

    Last modified: Wednesday, October 10, 2018 9:34 AM | Anonymous
  • Sunday, September 09, 2018 11:43 AM
    Reply # 6661040 on 6660513
    Al Moon (Administrator)



    Looking forward to this topic and more at the annual MGPHO meeting in Atlanta Oct 3&4: Plus, I do have one question and a statement.




    I understand that CO2 is provide in two types of cylinders.

    I believe one has a dip tube and one does not.

    If that's is correct, which type cylinder was delivered to the medical care facility ?





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  • Sunday, September 09, 2018 1:12 PM
    Reply # 6661117 on 6660513

    Non-dip tube was delivered but if you’re using CO2 for hemp extraction you want to use a dip tube. 

     This was done by an amateur lab. 

  • Monday, September 10, 2018 7:16 AM
    Reply # 6662162 on 6660513
    Deleted user

    Don, how was this discovered?  Was the cylinder still 99+?

  • Tuesday, September 11, 2018 12:23 AM
    Reply # 6663736 on 6660513

      Odor doing a repair to the manifold that was damaged by the oil.  It still read 100% CO2 but had a high level of hydrocarbons. 

  • Tuesday, September 11, 2018 2:01 PM
    Reply # 6664855 on 6660513
    Al Moon (Administrator)

    Where do the CO2 Cylinders for the State of Hawaii originate ?

    High Hydrocarbon reading ?

    What is the threshold for Hydrocarbons in a USP CO2 Cylinder ?

    Who was the Gas Supplier ?


  • Wednesday, September 12, 2018 1:23 PM
    Reply # 6666461 on 6660513

     I don’t think were supposed to list names on the forum but it is the largest medical gas supplier in the world. 

     The CO2 cylinders are  filled and shipped in from the mainland for Hawaii. 


  • Wednesday, September 12, 2018 9:41 PM
    Reply # 6667084 on 6660513

    The USP/NF Official Monographs are silent on hydrocarbons for C02, therefor there is no upper limit. 

    I believe medical cylinders should have a vacuum pulled on them (to remove residual gases) before refilling by the gas producer, therefore in theory, should have minimal/no odor. Bob S., is this true or could there still be an odor present?

  • Thursday, September 13, 2018 2:16 AM
    Reply # 6667209 on 6660513

     George you’re right with USP there is no upper limit on hydrocarbons. There is if you’re talking about food grade. But CO2 should still not have high levels of hydrocarbons indicating that there is a problem. You are also correct that they pull a vacuum on the individual cylinders before filling them.  If there is  hemp oil inside the cylinder in a liquid form it will continue offgassing at about 70°F. 

  • Friday, September 14, 2018 7:39 AM
    Reply # 6668946 on 6660513

    Yes a vacuum should be pulled on all cylinders being filled with a medical grade product. One of the problems with Co2 is that it has a slight pungent odor. 

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