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More worry about ethidium bromide contamination - (Apr/30/2006 )

Hi,

I know this has probably been done to death but unfortunately I have had a very obsessive-compulsive and paranoid approach to ethidium bromide contamination. There are a couple of reasons for this.

Firstly I haven't always followed the correct protocols: for instance, I used a pen (that also doubled as a USB drive) whilst wearing a nitrile glove that had touched an EtBr-containing gel. (It was more than a year ago and I don't know if there was much if any actual gel on the glove.) I didn't think about it at the time, but my worry has been that I've transported the USB drive around the place and then things that the USB drive have touched would be contaminated with EtBr, posing a risk to others, and these things touched by those things etc would then pose a risk of contamination to others... Also I dropped a small amount of gel on the floor (quite a bit smaller than a Minty, I suppose) but didn't clean it up for ages and have then been worried that places I've walked on would be contaminated with EtBr.

Secondly, I either have followed the correct protocols or have done things that, while still dubious, are less dubious than those written above...eg, touched the thermal cycler or papers in the lab with contaminated gloves on that I don't intend to touch ungloved, or used the microwave we use to melt the gels with contaminated gloves...but then others have touched things such as the buttons on the microwave or the thermal cycler. Would them touching these things pose a risk to themselves or to others (if they then touched other things)?

I know this worry has quite an obsessive-compulsive nature, and I have read other posts on this forum saying, for instance, that 18x less revertants were caused by a single cigarette than by x amount of ethidium bromide- but I really do need reassurance (and references if possible), I really don't enjoy this worry!

Thanking you in advance,

Matthew

-flametrees-

I should hasten to add, I now take far better precautions in terms of my own personal protection against potential EtBr contamination than those two incidents mentioned in the previous post.

-flametrees-

QUOTE (flametrees @ May 1 2006, 09:25 AM)
I should hasten to add, I now take far better precautions in terms of my own personal protection against potential EtBr contamination than those two incidents mentioned in the previous post.



Yes there is a risk.
However, when you cross the street, there is a risk that you are killed, when you eat, there is a risk of salmonellose, when you run after the bus, there is a risk you have a heart failure.
Don't think anymore about what you did, but try know to reduce risks as much as possible.
human do mistakes, stupid guys insists in their mistake and smart guys learn from their mistakes
OK, smile, now you are careful. wink.gif

-Missele-

hi
i tend to think as you for the people who touch gels and directly after their pipettes and light-buttons, door handles.... that drives me crazy. So for all that is EtBr related, i wear gloves, and for the rest, i wash regulary my hands... can't do an other way.

-fred_33-

Ethidium bromide is basically harmless as it can't get through your skin. If you want to worry about something worry about breathing in chloroform which is a known human carcinogen.

Daniel

-Daniel Tillett-

I would take handheld UV lamp and check the areas or devices that you think are contaminated, You will see if EtBr is there.
But honestly, if you would have been member of my lab, I would have screamed at you like hell. I am not paranoid about EtBr as such but I am hell paranoid about the way people handle it and risk other life!!

-Jiang M-

Thank you to all those who have replied to my post. I have read previously (although on forums rather than in the literature) that EtBr binds more strongly to protein than it does to DNA, and also will not cross the lipid bilayer (is it actively transported into human cells...?).

Regarding the UV lamp, I performed an experiment of my own and rubbed a gel I had been using with an Eppendorf tube (now safely in the biohazard bin!) and had a look under the UV illuminator, it did not glow so therefore would it be safe to assume that there are negligible risks in terms of anything my glove had touched (I assume I didn't rub my gloved fingers in the gel!)

Also there would be negligible risk in terms of people touching things that had touched things that had touched EtBr etc and then eating, placing their fingers in their mouth or other routes of entry?

Thank you once again, and if anyone has any more responses to my post or any responses to the queries in this post please send them forth!

-flametrees-

QUOTE (Jiang M @ May 3 2006, 05:15 PM)
I would take handheld UV lamp and check the areas or devices that you think are contaminated, You will see if EtBr is there.
But honestly, if you would have been member of my lab, I would have screamed at you like hell. I am not paranoid about EtBr as such but I am hell paranoid about the way people handle it and risk other life!!


The thing that really get me going is people who spill phenol on things and don't clean it up - I have been burnt a number of times over the years by phenol on centrifuges and door handles.

-Daniel Tillett-