EtBr safety procedures

Jim Owens jow at
Wed Jun 16 09:28:08 EST 1993

In article <123285 at> Patricia Foster, pfoster at writes:
>   I am truly amazed at what people are reporting about lab practices.
>Here at BU we are under very strict regulations.  Our radiation
>protection office has been very tight since I have been here 
>(8 years), and the chemical safety office has gotten stricter
>since OSHA regulations went into effect last year.  The chemical
>regulations have been particularly burdensome as the university
>has required every laboratory to keep up-to-date inventories, all
>the MSDS's, and usage and disposal protocols for *every* chemical,
>even NaCl.  This represents a lot of wasted effort, coming out of
>research time and money.  So why aren't the rest of you out there
>subject to the same regulations?

By and large we are.  It's a function of how vigorous (nasty?) the
enforcers can be.  For example, at NIH OSHA regulations are unknown at
the lab level unless someone in authority asks our safety people about
them, but at WRAIR, where my wife works, there was a lot of noise about
OSHA regulations over a year ago.  Life was difficult for a while, then
the safety people seemed to lose interest in the follow-up.  They are
relying more on the new state-of-the-art building that will replace the
80-year old facility in 1996 to meet OSHA regulations.  Perhaps, BU
cannot afford damage suits as well as DHHS and DOD?

>  BTY, I am a mutagenesis person and I would like to see the
>actual data on the mutagenicity of bleached EtBr.  Can someone
>give me the reference where the numbers are actually given.

One of the messages in this or the other thread with the same name has a

>Bleach is, after all, a powerful oxidizing agent.  Also, remember
>that dilution is an effective and approved method for disposing
>of low-level hazardous materials. 

I don't know if our safety people ever published their results, but one
of them told me three or four years ago that in their hands the oxidation
products of EtBr were just as toxic as the starting material.  They had
no recommendations for how us lab rats could make EtBr safe for disposal.
 What that means in practice, in my group at least, is that we dispose by
dilution usually.

Jim Owens

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