Disposing of petri dishes

[deleted-630769]

I am doing an experiment which involves growing bacteria and setting it underneath a UV light. After I have grown the bacteria and done the experiment what are the proper steps I should take the getting rid of the pretri dishes I have used (They are plastic I will be disposing of them). Can I just throw them away with the bacteria inside? or should I take more steps? Also is it safe to open the petri dishes to dispose of the bacteria? I have seen numerous articles saying not to open the dishes once the bacteria is inside.

[17eugenekim]

Hello there,

Glad to see you're aware of lab safety! The answer to this question ultimately depends on what the bacteria is. If you are doing an experiment like that, I am assuming it is non-pathogenic. Please make sure to check before you follow the next steps!

Though you could technically throw them away as normal (bacteria are everywhere, after all), to be absolutely certain that you're not letting dangerous bacteria go, you should disinfect the dishes. You can do this with just regular bleach. Give it a swirl in the dishes, making sure it's hitting all the surfaces, and dump it. Be careful not to get the bleach on your skin or eyes! Wear protection if necessary!

[SciB]

Hey,

I'd just like to jump in here to add something to Kim's great answer.

- You should always sanitize Petri dishes containing nutrient agar, even if you are using the harmless E coli K12 bacteria. Pathogenic bacteria are found everywhere and they can grow on the agar after you have put it in the trash and possibly infect a person handling the trash later.

- The bleach, Clorox usually, does not need to be used at full strength to kill bacteria. Diluting it to 10% and letting the Petri dishes soak in a pail of this is sufficient for sanitizing.

- Whenever doing any kind of lab work ALWAYS wear eye protection, disposable gloves and a lab apron or coat.

Sybee