how hazardous are these substances really ?

walter23 said:

This is terrible advice. An MSDS is just as valid for casual, low scale users, or chemical laboratories using small quantities, as it is for large scale industrial operations. In fact, an MSDS tells you just how relevant it is for low scale use vs. large scale use by virtue of the information on toxicity, acceptable exposure levels, reactivities, and the likes. It's full of very useful information.

For example, using a couple of random example compounds: something like KCN (potassium cyanide) is very toxic (a gram or so can kill you if ingested), irritating, liberates toxic cyanide gas if heated or reacted with certain subjestances, etc. Potassium dichromate (a more relevant example for photographers) is acutely toxic and will give you cancer with repeated exposure to small amounts. These are all properties that would be relevant to you whether you've got 1 gram of it sitting in a bottle on your desk or a 10 ton vat of it sitting in a large scale industrial facility, and this information is all available in the appropriate MSDS.

Click to expand...

walter, that was a Richard Knoppow quote that I posted:

Richard Knoppow on Pyro toxicity: Source (http://www.viewcamera.com/pyro.html)

“Pyrogallic acid is toxic but one must be careful in interpreting MSDS: mostly they are written for industrial users of substances who use and store them in very large quantity.

In our laboratory at work, we have a large MSDS library which I consult frequently. I agree with Knoppow that one must be careful in interpreting any MSDS. Different MSDS on the same chemical often give contradictory information.

And all too often, the MSDS appears to be selling a corporate position.

I would have to agree with Tom in this.

The MSDS is often written for laypeople who are involved in fire and rescue operations. They have to know how to treat a substance in a hurry in case of injury or fire. The MSDS is a generic paper that often gives misleading information just for safety sake.

PE

To paraphrase a temperance slogan of many years ago, a drop of nicotine on the tongue of a mouse is enough to kill a man. I don't mean to make light of these things, but only of the ways some (not among us) use to describe their danger. Also, I like to let everyone know that I am still alive after all these years of doing things that could have killed me if I had not been a bit careful. Who else remembers the Women's Temperance League?

Among some of the most dangerous chemicals I dealt with was a cyanide bath used for cleaning trumpets and other brass instruments prior to lacquering. I was repairing musical instruments part time while studying chemical and aeronautical engineering (a long story) and was told by the boss man of the hazards involved. The bath had to be kept quite basic to prevent generation of cyanide gas. Scary, ain't it?

john_s said:

Blue nitrile gloves are available at my local (not very good) supermarket, so I would think that they would be easily available.

Click to expand...

My local Walgreens carries nitrile golves and they are not expensive.

Photo Engineer said:

Unfortunately, during a workup I had an accidental spill of selenium oxide in dimethyl sulfoxide. Jordan will recognize the danger of that combination.

It did penetrate the skin and I could taste garlic and oysters for a day.

Click to expand...

PE - The garlic taste could have been from the DMSO as well - hard to tell which would have caused the taste in this case. But SeO2 only takes a few tenths of a gram to get you with sking contact appearantly.

The DMSO was oysters! The garlic was Selenium in some form or another. It was awful tasting and I smelled funny. People on the bus going home were asking what that odd chemical odor was. I knew!

PE

Photo Engineer said:

The DMSO was oysters! The garlic was Selenium in some form or another. It was awful tasting and I smelled funny. People on the bus going home were asking what that odd chemical odor was. I knew!

PE

Click to expand...

As a grad student and as a post-doc I did a fair amount of work with a 0.5 M solution of sodium azide in DMSO. Great source of N3- for making organic azides, but I was absolutely terrified of getting it on my skin. If any significant quantity had gotten through, I don't know if I would have lived to describe the taste

We had one grad student become a vegetable from inhaling methyl sufate by accident, and another was killed by an accidental prick from a GPC syringe. The chemical in that minute amount, about 1 micro liter or less was lethal within a few minutes. These were not at our school, but at another one in the same city.

PE

Photo Engineer said:

The DMSO was oysters! The garlic was Selenium in some form or another.

Click to expand...

Oysters - Interesting. I've always heard garlic for DMSO, but I see wikipedia mentions both oysters and garlic.

I don't like oysters, but I do love garlic...

DMSO is a byproduct of the wood pulp industry. It is found in dandelions and is foraged heavily by animals about to hibernate, as it reduces ice crystal formation in cells. It has a heavy unpleasant smell suggestive of oysters in its pure form.

It is non-toxic itself, but by virtue of it being an almost perfect solvent and being able to penetrate skin, mixtures of it with toxic substances becomes quickly lethal. This is why it is banned today. It was being used in sports as a solvent for pain killers which mixture was then spread on injuries for instant relief. This only led to more injury.

At one time, solutions of DMSO and asprin were available as a rub for the head. It gave instant relief there as well, for headache as the asprin hit the brain almost instantly.

The danger lies in having something else hit the brain instantly as well. Too many people tried that route and didn't survive.

It has been recently found that DMSO added to emulsions while making them gives higher speed and finer grain. See proceedings of the ICIS 2006 for the information.

PE

Photo Engineer said:

We had one grad student become a vegetable from inhaling methyl sufate by accident, and another was killed by an accidental prick from a GPC syringe. The chemical in that minute amount, about 1 micro liter or less was lethal within a few minutes. These were not at our school, but at another one in the same city.

PE

Click to expand...

What was in the GPC syringe? Me2SO4 as well?

Well, IDK, but my understanding was that it was newly synthesized and the GPC was going to be used to get information about the mix in the pot. The syringe was being carried along with some others, down a hall to the analytical lab when someone ran into the person carrying the tray. One of the syringes pricked him.

The needles were pointing outward with the barrels in the tray for stability IIRC. IDK why they didn't use a bigger tray for safety. They were apparently using a small glass EP tray.

The story travelled fast among the grad students all over the city at all 3 major Universities.

PE