A few minutes ago I was desoldering micro controllers from an old laptop of mine. Unfortunately I didn't pay enough attention to the area that I was heating with my hot air gun and eventually managed to blow a cap. I remember seeing a rather big ring of white smoke and immediately rushed outside, coughing as much as I could.

I'd like to know if there are any health concerns I should be aware of regarding the toxic smoke that came out. Can It cause serious lung damage?

It's a surface mount capacitor:

Photo of that capacitor

Source: http://img.dxcdn.com/productimages/sku_156107_2.jpg

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    \$\begingroup\$ One capacitor won't do anything to your lungs/respiratory system...Like literally nothing. \$\endgroup\$ – zack1544 Jan 12 '17 at 0:19
  • \$\begingroup\$ But if you blow up a cap due to overvoltage/reverse polarity(electrolytic)...hot material can fly at you so don't do that. \$\endgroup\$ – zack1544 Jan 12 '17 at 0:22
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    \$\begingroup\$ As an asthmatic kid interested in electronics, I remember having similar concerns the first time I really popped a cap, when I got the polarity wrong on an electrolytic. Considerable voltage and a lot of foul smelling steamy smoke ensued. I imagine repeated exposure could eventually cause poisoning, but having breathed the smoke of a lot of electronic mishaps over 50 years, I'm pretty confident in telling you not to worry about it. But as already advised, let it be a wake up call regarding eye protection. \$\endgroup\$ – Randy Jan 12 '17 at 0:37
  • \$\begingroup\$ You might die, or you might live \$\endgroup\$ – Voltage Spike Jan 12 '17 at 5:05
  • \$\begingroup\$ Are you not using a fume extractor? If you're concerned about lung damage, the smoke that comes from the flux every time you solder something is probably what you should focus your attention on. \$\endgroup\$ – Dampmaskin Jan 12 '17 at 12:52

If it was a "wet" capacitor with a gel / liquid electrolyte, that was likely either ethylene glycol (aka "anti-freeze") or boric acid (think Borax laundry soap). If it was a solid capacitor, the equivalent of an electrolyte was another film of manganese dioxide (MnO2). Wet caps usually pop, but not smoke.

Given the puff of smoke, I'd say it was likely a solid cap, because the MnO2 is an oxidizer that burns at high temperatures, such as one finds when things go "ZAP". You would have inhaled maybe a few micrograms of that, plus a few of aluminum oxide. Every time you have used a finger nail file, you have inhaled probably thousands of times more aluminum oxide than you got from that cap. Manganese oxide is used in tattoos and makeup all the time. Nothing to get excited about in the quantities you were exposed to.


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