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disposal of "contaminated" plates - (Mar/20/2014 )

Hallo,

 

I am curious how your labs deal with contaminated agar plates.

 

Most of my work is done in a L2 lab. In my opinion you should trow contaminated (but unused) plates away in the specific waste bins (for biological waste).

 

However, I seem to be the only one that thinks this.

The general idea is that contaminated plates should simple be put in the regular waste bins. The reason they give me is that its just airborne contamination and nothing "bad".

 

I do not agree with this.

 

What are your ideas?

-lucilius-

You mean with 'contamination' just not sterile anymore (whatever type of bacteria is growing)?

-hobglobin-

hobglobin on Thu Mar 20 19:24:08 2014 said:

You mean with 'contamination' just not sterile anymore (whatever type of bacteria is growing)?

Indeed, plates that have been contaminated.

And yes: whatever type of bacteria/fungi/yeast is growing on the plates.
 

-lucilius-

These should be treated as contaminated waste.

-Phil Geis-

Phil Geis on Thu Mar 20 22:12:37 2014 said:

These should be treated as contaminated waste.

I agree completely, however I am in a similar situation where "from the top" this rule is also stated that plates that were poured and got contaminated (at your bench for example) are not regarded as biowaste. They are also just town in the waste bin.

Its sad how it sometimes is in academia.

-pito-

Phil Geis on Thu Mar 20 22:12:37 2014 said:

These should be treated as contaminated waste.

 

You do mean to trow it in the biological waste bins?

-lucilius-

I mean treat these as you would any media exposed to microbes - inoculated by intent or otherwise.  Whereas this is unlikely to run afoul of fed regulatory attention unless you're regulated by FDA, many state EPA's regulate disposal of hazardous (including biological wastes) and would likely find this practice in violation.

 

This is a pretty cavalier disregard for safe practices. 

 

Let me ask one more - how do you dispose of inoculated plates that showed no apparent growth?

 

To your question, i suggest you clearly communicate your concern.  No one knows what's growing on the plates.  In any case, have your management document the practice they demand by SOP. Folks may be less cavalier when they have their name associated with a questionable practice.

 

Here's the OSHA lab standard for info:  https://www.osha.gov/Publications/laboratory/OSHA3404laboratory-safety-guidance.pdf

You'll read - "Employers may use the list below as a starting point for technical and regulatory information about some of the most virulent and prevalent biological agents and toxins"

Included in that list is the relevant comment - "Molds and Fungi. Molds and fungi produce and release millions of spores small enough to be air-,water-, or insect-borne which may have negative effects on human health including, allergic reactions, asthma, and other respiratory problems."

 

Not that OSHA is esp. smart (molds ARE fungi) but this caution is relevant to your concern.

-Phil Geis-

Strongly agree with Phil. I personally would not want to work in that lab. Others in the lab are also probably cavalier about level 2 pathogens. Complain.

-phage434-