how to dispose of e.coli cultures?

[twistii]

hi, i have grown some e.coli cultures for quite a while now and im wondering how to dispose of them? i dont have access to an autoclave or any biohazard bags... how can i safely dispose of my e.coli k12 strain petri cultures using household materials? would immersing them in 99% alcohol work? could i immerse them in the alcohol and let it sit for an hour and then take out the petri dishes with gloves on and put them in a trash bag and throw them away?

[amyC]

Hi - This is a very good question. The following information from the Science Buddies Project Guide I think will help:

Note on Clean-up and Disposal

When you are completely done with your experiment, you will need to decontaminate any plates you used. More than likely, you will not have access to an autoclave for sterilization. Another way to decontaminate your experimental materials is to use disinfectants. The best disinfectant is household bleach at 10% strength. You can make a 10% bleach solution by mixing one part of regular laundry bleach (e.g. Clorox®) with 9 parts of water. Other general common household cleaning reagents are also effective at decontaminating bacteria, and can be used. Decontaminate plates by carefully opening, and pouring a generous amount of disinfectant (i.e., 10% bleach) onto the agar surface. Leave the plates to soak for at least an hour. The sterilized, decontaminated plates, can then be disposed of in your regular household garbage, but ONLY after sterilization, as described, is complete.

This information appears in the "Microorganisms Safety Guide": https://www.sciencebuddies.org/science- ... fety.shtml

Amy
Science Buddies

[deleted-212476]

Another good way to get rid of bleep like that is to put them in a bag with kitty litter, coffee grounds, or soil and then dispose of them in the garbage. This is how people in nursing homes get rid of un-used/ expired medicine when a bio-hazard bag or cement aren't available.