# Liquifying metal and toxic fume exposure

I just read a very entertaining Youtube comment thread on a video where TheBackyardScientist melts tin on the stove in his (enclosed) kitchen, the proceeds to cook a steak on it.

According to the mass of commentaries (and votes), what he did was idiotic due to the toxicity of the fumes released when melting the tin, and the fact that he was in an enclosed space without a respirator.

Reading about tin and organotin compounds a bit, nothing is mentioned about them being 'released' upon melting, but rather that they are a particular subset of compounds of tin, and some happen to be toxic.

Regarding 'metal fume fever' and its causes, it seems that it is a small subset of metals that when oxidized could cause nervous system damage, in which tin does not take part.

Aside from burning yourself horrendously, what dangers are associated with the melting of (we can assume nearly pure) tin, particularly in a closed space? Is what he did really that dangerous?

• None of the organic compounds of tin would survive till the melting point of the metal. As for the rest, well, when compared to other heavy metals, tin is not all that dangerous. – Ivan Neretin Feb 5 '16 at 17:45
• The "pure" tin probably had more than a bit of lead. Such a stunt in a kitchen in which you're going to eat is just absolutely stupid. – MaxW Feb 5 '16 at 19:49
• Copper pots, kettles and food cans used to be TINNED because it was a relatively inert metal. As a metal there is little risk, metal fume fever is usually transient but can be very bad from zinc, not sure of tin. Tin dust would be the result of grinding or other ways of powdering it, seems not to be a significant issue here. Fearmongering is not a word but it is a modern trolling sport. – KalleMP Dec 3 '16 at 22:48

Aside from burning yourself horrendously, what dangers are associated with the melting of (we can assume nearly pure) tin, particularly in a closed space? Is what he did really dangerous?

According to the SDS for tin metal from Sigma-Aldrich, tin metal (at the purity level for the product mentioned here, which is <= 100% and may not be that of what was used in the video you mentioned) is not a hazardous substance or mixture.

There is some danger specifically relating to inhalation of tin dust or aerosols (see sections 6.1 and 7.1 in the linked document):

6.1 Personal precautions, protective equipment and emergency procedures Use personal protective equipment. Avoid dust formation. Avoid breathing vapours, mist or gas. Avoid breathing dust.

7.1 Precautions for safe handling Avoid formation of dust and aerosols. Further processing of solid materials may result in the formation of combustible dusts. The potential for combustible dust formation should be taken into consideration before additional processing occurs. Provide appropriate exhaust ventilation at places where dust is formed.

In section 8.2 (Exposure controls) it is noted that:

Respiratory protection Respiratory protection is not required. Where protection from nuisance levels of dusts are desired, use type N95 (US) or type P1 (EN 143) dust masks. Use respirators and components tested and approved under appropriate government standards such as NIOSH (US) or CEN (EU).

In section 11.1 (Information on toxicological effects, a subsection of Toxicological Information), information pertaining to toxicity can be found. Inhalation here will refer to tin dust or aerosols that can be inhaled:

Acute toxicity

LD50 Oral - Rat - male and female - > 2,000 mg/kg (OECD Test Guideline 423)

LC50 Inhalation - Rat - male and female - 4 h - > 4.75 mg/l (OECD Test Guideline 403)

Dermal: No data available

If the tin was/is at the near 100% purity level, the main risks associated with handling it are associated with the formation of dust (workplace inhalation limits are given in section 8). The HMIS (Hazardous Materials Identification System) ratings in section 16 are 1 for health hazard, 0 for flammability and physical hazard, and no value assigned for chronic health hazard.

Conclusion: Assuming the person in the video did not inhale or ingest tin dust (a proposition that largely becomes moot after it has melted, in any case), there appears to be little to no danger associated with the activity with respect to melting tin in a closed space (especially such a small amount of it).

• :-( First I doubt that some knuckle head who wanted to try cooking with molten tin is going to spend hundreds of dollars for high purity tin. Second cooking with it is different than just melting it. Once you melt it is going to oxidize some and the oxide will form a skin on the surface. I'd be very worried that the oxide would concentrate the heavy metal impurities in the tin. So all in all cooking with molten tin is a stupid stunt that shouldn't be tried. – MaxW Feb 6 '16 at 18:18
• @Maxw tin is a bit more active than lead, and, more importantly, tin is widely used to cover tin cans. Thus, lead-free tin is not an issue. The stunt is no more stupid than consumption of $\ce{K4[Fe(CN)6]}$ – permeakra Feb 6 '16 at 21:29
• I did XRF for years. I understand that "pure" tin used in such a stunt could be safe, but I doubt the ability of most to understand what "pure" tin is. Very few people would have the ability to adequately test tin for impurities. Buying high quality tin (reagent grade) is very expensive. Cooking a steak with molten tin is just a stupid stunt that should not be repeated. Downplaying the risk is a disservice to the idiots who might be inclined to repeat the stunt. – MaxW Feb 6 '16 at 21:56

I have re-tinned some old copper cookware; no fumes, but it is not easy to get a mirror surface. I believe all old copper cookware is tin coated (essentially pure tin). "Tin" cans have less than a 0.001 in. coating of tin on the outer surface for corrosion protection; various organic coating are used on the interior. For salvage ,the tin is removed chemically. Zinc is another story. It is impressive to see a "zinc boil" in brass overheated in a foundry ($\ce{Zn}$ vapor pressure > atmospheric). I have had "zinc chills", you get over it in a day. But I do recommend avoiding $\ce{Zn}$ vapor (ie zinc oxide).