Soldering vapor/fume toxic ? + solder help please

Thread Starter


Joined Mar 24, 2016
Hey guys

I finished my first prototype (rgb led controller with Arduino) and want a more permanent solution.

So I bought some perf board, a solder station (45W 150*C - 450*C) and helping hands (and other stuff). I heated the solder pen up to around 330*C Like suggested by a lot of youtube videos. But before actually soldering stuff to the perfboard, I wanted to practice first. I stripped some wires, put them in the helping hands and put the solder pen against the copper wire (again suggested in a lot of youtube videos). Then when the copper was hot of a few seconds I applied the solder to the copper and it worked.

Now my question is if the vapor/fume that came of it while applying the solder is toxic. I used 60/40 (Sn/Pb) solder Link -

I didn't breathe it in, but I wonder how toxic it is, any solutions , place a fan next to it to suck it away ?

Thanks in advance


Joined Sep 20, 2005
It is not very toxic, just might irritate your lungs if you are sensitive. I just try to not breath it in, or gently blow at the soldered point to get the smoke off my face if it is really annoying.


Joined Jan 18, 2008
The organic components in the flux can cause irritation. For example, rosin contains abietic acid (, which is a known respiratory irritant.

As for lead, its vapor pressure is <10^-6 mm Hg at typical soldering temperatures (see: ), which is considerably lower than zinc or cadmium at the same temperature.

I agree with the general advice that soldering with lead-tin alloy is not a concern for the hobbyist.



Joined Oct 15, 2009
As stated the "smoke" is flux and is a mild irritant for some. (may get sore throat/coughing/dizzy/upset stomach,etc...)
However.. The danger with leaded solder is not in the fumes as soldering temperatures are not sufficient to vaporize the lead.
Its that small lead particles that blow around/get on your hands/clothes/desk, etc.. and you can transfer that into your mouth/food,etc..

So.. Use a fan to keep the smoke away from your face and always clean your work surface/surrounding area as well as wash your hands before you eat/drink/smoke/bit your nails,etc....
No open food or drink around you..
Follow the same "hygiene" with any solder.

But again as stated for the "average hobbist" that only maybe solders for a few minutes a few times a week if that its usually not an issue at all.. but still wash,etc..
The concerns are with those that solder for 40+ hours a week and are in continual contact with it.. You can be exposed to enough in a regular work shift to exceed OSHA recommended daily limits,etc..

oh and you will get some that say they have been doing it their entire life sucking on the roll of solder and have no ill effects.. Thats just silly.. The hazards are proven and the dangers are there..
I've been a smoker for 25+ years and feel totally fine.. That doesn't mean it hasn't effected me..
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Joined Jan 18, 2008
I've been soldering for over fifty years, with no ventilation and no ill effects.
I agree, but your comment brought a laugh to me. In the early 90's, I got back into RC models and started with composite sailplanes. Being composite, I used modern automotive finishes to get a great gloss. As a lot had changed since the early 60's, I visited a small shop in PA to see what he did for safety. The proprietor made the same comment -- except he was a crazy as a loon.

So, the ultimate question is, if you had lead toxicity, would you notice it? ;)


Hypatia's Protege

Joined Mar 1, 2015
Now my question is if the vapor/fume that came of it while applying the solder is toxic
If you're concerned about rosin and Pb fumes, an air purifier featuring an activated charcoal filter will greatly reduce said contaminants -- That said, Pb vapor is essentially a non-issue at the temperatures involved whereas the rosin (and pyrolysis products thereof) would pose a (significant) issue only in the case of sensitized individuals or where marked respiratory decompensation is manifest --- Re: Pb, the larger issue, as stated in a previous post, is that of particle dissemination and, to a lesser extent, contamination during handling --- So... Observe good 'technique' - and I daresay you'll survive to prototype another day:D

Best regards
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