Gallium is not known to be toxic, though there isn't a huge amount of data on its toxicity. It also has a much lower vapor pressure than mercury, even at high temperatures (it doesn't evaporate readily), so you won't inhale much. I wouldn't eat it though. Its physical properties are a lot like aluminum.<br>
<br>There's an msds <a href="http://www.espi-metals.com/msds%27s/gallium.pdf">here</a>, from which:<br><br>Health Hazard Information<br>Exposure Limits in Air: (TWA or suggested control figure): There is no specific TWA established for this product. <br>
Acute Effects: <br>Inhalation: No inhalation hazards of gallium have been identified. Good industrial hygiene practice suggests limiting exposure to all <br>repairable particulates. <br>Ingestion: Evidence suggests low toxicity potential due to poor absorption by the oral route. <br>
Skin: May cause irritation. Some sources suggest gallium may cause dermatitis, although patch testing humans with metallic <br>gallium did not cause a positive reaction. <br>Eye: May cause eye irritation. <br>Chronic Effects: Intravenous administration to humans caused metallic taste, skin rashes and bone marrow depression as well as<br>
anorexia, nausea and vomiting. May cause damage to kidneys. <br>Carcinogenicity: This product does not contain any ingredient designated by IARP, NTP, ACGIH or OSHA as a probable human <br>carcinogen. <br>Medical Conditions Generally Aggravated by Overexposure: No data found. <br>
<br><br><div class="gmail_quote">On Fri, Jun 5, 2009 at 4:54 PM, Andrew Cantino <span dir="ltr"><<a href="mailto:cantino@gmail.com">cantino@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
Isn't gallium toxic like Hg?<br>
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On Friday, June 5, 2009, Noah Balmer <<a href="mailto:noahbalmer@gmail.com">noahbalmer@gmail.com</a>> wrote:<br>
> It is fairly uncommon for liquids to expand when they fuse. I think bismuth does the same thing, and water does, as you mentioned, but don't know of anything else offhand. In the case of water it has to do with a crystal structure that requires more space than the amorphous liquid does*. I don't know what the mechanism is with gallium. It has conchoidal fracture, which is commonly seen in amorphous glassy solids, so I think it may be some other mechanism, but it may just be a very fine grained crystalline structure.<br>
><br>
> -N<br>
><br>
> *Water molecules are approximately L-shaped. When they can flow feely around each other they can spoon and hook around each other in all sorts of ways that increase the density. When they are frozen into a regular grid, the inside of the L is empty, so they are packed less densely. Pressure on ice near the melting point can disrupt the crystal structure and re-liquify it, which is one of the reasons ice skates work so well. A gallium skating pond might work too, though gallium loves alloying so much it might just dissolve the blades (it dissolves aluminum readily, don't bring it on a plane!) , and in its liquid form it's kind of sticky.<br>
><br>
><br>
> On Fri, Jun 5, 2009 at 3:48 PM, d p chang <<a href="mailto:pchang@macrovision.com">pchang@macrovision.com</a>> wrote:<br>
><br>
> Noah Balmer <<a href="mailto:noahbalmer@gmail.com">noahbalmer@gmail.com</a>> writes:<br>
><br>
>> I'm surprised to see it stored in a glass vial in that image<br>
>> though, because it expands by a few percent when it solidifies, and<br>
>> will often break rigid containers.<br>
><br>
> wow. i thought water was 'weird' that it expanded when it became a<br>
> solid. am i just mis-remembering something or is this actually common?<br>
><br>
> \p<br>
> ---<br>
> I know that you believe that you understood what you think I said, but I<br>
> am not sure you realize that what you heard is not what I meant.<br>
> - Robert McCloskey<br>
><br>
><br>
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