EtBr substitution - (Oct/17/2006 )
Hi all !
I'm new on this great forum 
Our safety department wants to get rid of EtBr in all our labs. We will have to work with Sybrsafe...and if Sybrsafe is not satisfying (with small and poorly intense bands on little agarose gels ... where sybrsafe gets out of the gel too fast), we will have to use gelred...
After consulting the gelred MSDS, I saw that it was also an intercalant, was also mutagenic in the Ames test in bacteria. What do we know about toxicity on eucaryotic cells ? What about the fact that gelred is dissolved in DMF (very toxic too) ???
I don't understand this new battle against EtBr... 
Has anyone seen this substitution policy in another lab ?
I dont get it, whats the big deal with EtBr, as long as people wear gloves and are careful
my lab has been looking for alternatives to EtBr... and not much success... tried
1-methlyene blue
2-sybre green
3-zinc imidizol
EtBr remains the fastest and strongest staining.
We've switched to Sybrsafe for all of our work, and see little difference from EtBr. I personally don't see the point, but it seems to make the students feel safer. You know, the fumes.... ;-}
I have seen people handling stained gels without gloves. While I never do that, I will report if those ppl get mutated.
P.S.-> they KNOW it is a powerful mutagen.
Princeton University H&S states this:
Trace amounts of ethidium bromide in gels should not pose a hazard. Higher concentrations, e.g., when the color of the gel is dark pink or red, should not be placed in laboratory trash. EHS recommends the following:
Less than 0.1% ethidium bromide: place in laboratory trash
http://web.princeton.edu/sites/ehs/chemwaste/etbr.html#gel
But I bet that your colleagues do use more than that minimal amount.
People!
remember:
Intercalation is a term used in host-guest chemistry for the reversible inclusion of a molecule (or group) between two other molecules (or groups). The host molecules usually comprise some form of periodic network.
Intercalation is found in DNA intercalation and in graphite intercalation compounds.
These structural modifications lead to functional changes, often to the inhibition of transcription and replication processes, which makes intercalators potent mutagens.
DNA intercalators are often carcinogenic, such as benzopyrene diol epoxide, bisbenzimide, aflatoxin, or ethidium bromide.
Maybe we use a very a little quantity today, and... tomorrow and the day after tomorrow... and so on... not so good....
bye.
M.