Another one worries about ethidium bromide contamination - (Sep/08/2007 )

Hi all
I know this may sound crazy,but I just can't get rid of these ideas
I worked in a lab for like 3 or 4 weeks,at first everything seemed goes well until one day I found that when a labmate carried a gel whih 0.5 ug/ml EtBr to the image equipment,a drop of buffer droped from the gel to the floor.After that I found this seemed to happen every day.And a few days ago a labmate told me that a gel once falled from his hand to the floor and scattered,he just picked them up mechanically.I was not in lab that day so I don't know which area is possibly contaminated.
Then I become worried.caus when i stepped on the floor,my shoes could be contaminated,then when I walked back to my dormitory about 600 meters from the lab,is it possible that the some residual EtBr on my shoes would contaminate the dormitory floor? And even worse,the electrical outlet of my dormitory was on the floor ,so once or twice I may accidently step on the charger of my cellphone battery.then when I use my cellphone,my finger....and then I may touched food with my fingers ,I may went to the washing room and touched my....well,you know what I mean.
Ok,OK,I know I may goes too far,but these ideas keeped troubling me these days,I really need some advice.

usage of EthBr should follow strict rules in a lab; to monitor contamination, try to find EthBr with UV-light (f.i. flow UV lamp if ambulant) if it has become dark in the labs; ask your security official for advice

I have no idea how much EtBr it takes and exposure for how long will give significant risk of carcinogenesis but reading the description, I fear you are not only cautious which is good but slowly slipping into a state of phobia.

well asically you don't lick your floor ?
i would say the EtBr is "diluted" on the road of your 600meters. I don't think contamination is still there. If you're truly scared, you may change your shoes after your lab day. These were shoes for the lab only.

Yes I think I'm kinda phobia now
I have change a pair of shoes for lab use only
what's troubling me now is that should I throw the things away that might be contaminated in my dormitory?

Well, you can use something else such as SYBR Green, GeneFinder, Goldview instead of Ethidium Bromide, these materials are not considered as carcinogens. Nucleic acids stained with SYBR Green and GeneFinder could be visualized under blue light (I don't know if Goldview could), the excited light is green or green-yellow. All of the three fluorecent dye can be excited under UV as EtBr does. The latter two GeneFinder, Goldview are from Chinese companies, their prices are close to EtBr.

The sunlight you are exposed to going to and from the lab is more carcinogenic than the EtBr. As are any number of mold compounds in the soil you are walking over.

1) EtBr has not been shown to be a carcinogen AT ALL. It is a mutagen to bacteria.
2) The amounts you are talking about are in the nanogram range.
3) If this continues to bother you, I'd suggest a change in majors.
4) You need to worry about the truly dangerous chemicals like phenol and formaldehyde

thank you guys,really appreciate,
I feel much better now.