[SpellForce]

Hi,
I would like to know how dangerous is to work with 2,4 dinitrophenol, in an open container, under 26 degrees? Its concentration is around 1mM...
Is it releasing toxic gases? Should I wear glases and a mask? In the product description, they made it look really dangerous, but I wanna know how people work with it?

Thank you.

[discodermolide]

What solvent is it dissolved in?

[SpellForce]

LB, growth media for bacteria.

[Babcock_Hall]

Just speaking offhand, my guess is that ingestion is the main route by which it would show its toxic effects.  However, I would wear gloves and avoid direct contact with skin anyway.

[SpellForce]

And what about gases and evaporation?

[discodermolide]

At 1 mmol the amount of phenol in the gas phase will be vanishingly small. So don't worry about it, it's an aqueous solution.
If you are still worried use it in a fume hood and keep your gloves on.

[SpellForce]

The problem is that I have to use it in a petri dish, within a microscope, so fume hood is out of the picture. However, I use fume hood to weight it out. But it changed color of LB to light yellow and that scared me a bit, so I quit the experiment and put all in one container. Now I dont know where to dispose the container...

[billnotgatez]

Lysogeny broth (LB)
??

[SpellForce]

Yes, Lysogeny broth.

[discodermolide]

The problem is that I have to use it in a petri dish, within a microscope, so fume hood is out of the picture. However, I use fume hood to weight it out. But it changed color of LB to light yellow and that scared me a bit, so I quit the experiment and put all in one container. Now I dont know where to dispose the container...

I would expect the solution to be slightly yellow. So don't worry about that.
It's good to have respect for the chemicals you are working with, but please don't be scared.
Send the container for incineration.

[Borek]

In the product description, they made it look really dangerous

They always do.

You work with a 1 mM solution, most likely small volumes, but let's say 100 mL in total. That means 1 milimole, or 0.018 grams (18 mg). Assuming you drank it (which I assume you will not), and assuming your body weight of around 70 kg (no idea if you are female/male/tall/small, but it all doesn't matter much when checking order of magnitude), you would consume around 0.25 mg/kg of body weight. Wikipedia article on http://en.wikipedia.org/wiki/2,4-Dinitrophenol says

Case reports have shown that an acute administration of 20–50 mg/kg in humans can be lethal.

That's 100 times higher dose. Sure, you should treat your reagents with care and take normal precautions, but I am absolutely sure there are far more dangerous chemicals in your lab.

[SpellForce]

Ok, thank you guys for this, I really appreciate it.

I just have one more question. It says that it is light sensitive... What does it actually mean?
I am shining light into my petri dish, containing LB + DNP (from microscope, in 5 ml, around 2h), is this damaging its stability, or induces some evaporation? I can work under dark environment, but then also until I weight it out and dilute it, it is not in the dark.

Sorry for such basic questions, but I need to make sure I do everything right.

[Babcock_Hall]

Ordinarily, when I see LB, I think it stands for Luria broth.

[Mellitic]

The yellow color is certainly normal for nitrophenols.  As others have said, just wear your PPE and remove your gloves quickly if you get any solution on them, and you'll be fine.  As for light sensitivity, as long as you are not using a high-pressure halogen lamp or working in direct sunlight, it should be stable for a while.  Don't worry about evaporation; its vapor pressure is 2 × 10^-10 atm (in compairison water is 0.03 atm).

Also, since no one else has mentioned it yet, be aware that DNP is explosive.  You shouldn't mess around with old bottles or any bottles with crap on the lid.  It's not all that shock-sensitive, but to be extra cautious, just don't use more than a gram, don't grind the powder or concentrated mixtures, and keep you solutions more dilute than <15% w/w.