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Wait, wait, hold the phone: > Once you use a soldering iron and you begin to melt it, then you begin to get gaseous lead and that can be inhaled and that's mor

Wait, wait, hold the phone: > Once you use a soldering iron and you begin to melt it, then you begin to get gaseous lead and that can be inhaled and that's more of an exposure problem. So the question would be, in a case like that, are they properly protected when and if that lead is mobilized? At normal temperatures, that’s Flux, not lead. “Gaseous lead?”

ghouse 3y ago
The CDC believes that: "Lead fumes are produced during metal processing when metal is heated or soldered." https://www.cdc.gov/niosh/topics/lead/workerinfo.htm https://www.cdc.gov/niosh/topics/lead/workerinfo.htm
- gjsman-1000 3y ago
  I am admittedly talking about electrical soldering, which the person quoted was also referring to, but there are different kinds. You would need to set your solder gun to about (edit 750, not 1100) degrees Fahrenheit to begin truly vaporizing the lead. Which, some soldering irons are capable of, but lead solder’s lower melting point of about 400 degrees makes the risk low. https://news.ycombinator.com/item?id=30629580 https://news.ycombinator.com/item?id=30629580
- Gordonjcp 3y ago
  The CDC believes a lot of fairly bonkers stuff that does not match up to reality. If you heated solder up to the point that lead was boiling off, your circuit board would be on fire. You cannot get lead poisoning from using leaded solder.
  - AlgorithmicTime 3y ago
    I mean if you start licking it or chewing it you might, but normal usage just wash your hands afterward and you're fine.
    - Gordonjcp 3y ago
      You'd have to eat a lot of solder. Metallic lead reacts with fuck all, basically, which is why it's such a good material for things like roof flashing. It doesn't even react particularly with the hydrochloric acid in your stomach, producing only lead chloride (which will make its way out of your body fairly quickly) and hydrogen gas (not enough to do anything fun if you burp while smoking a cigarette, but let's not take chances eh). Metallic lead is about as bioavailable as sand. No no, if you want to get lead into your system you've got to really try quite hard. Taking some lead and mixing it with tin won't get the job done, oh no, not even a little bit. You're going to want to make it into an organic salt, maybe by welding on a lovely big acetate and then getting that into your stomach. Now why would you want to do a thing like that? Well, you might be an ancient Roman, with a fondness for "defrutum", a sweet sticky confection made by boiling soured wine and grapes in a lead pot until all the water is driven off. The acetic acid rips lead out like nobody's business and gets well and truly stuck together. Oh, and it tastes really sweet too, this lead acetate, which is just the thing to liven up any Roman party if the wine's gone a bit funny in the sun. Now you've got a lovely big sugar that your digestive system will happily squish into your sensitive tissues, where it'll break up and be on its way leaving a big fat lead atom right there with nothing to bind to, until it finds something. Oh hey, you know that sugars - even with a great big lead atom weighing them down - cross the blood-brain barrier just fine, right? You couldn't design a better way to get lead poisoning. Now toss in some ergot mould because you won't eat the local wheat because everyone is going mad from something and it must be those wily locals poisoning you so you only eat rye shipped over from Rome in mouldy sacks, and pretty soon - between the brain damage from lead acetate and the hallucinogenic mould - you're ready to turn horses into senators, and tell your soldiers to blunder into midgie-infested marshes in the North of Scotland where they sink out of sight never to be seen again. Lovely.
singlow 3y ago
Maybe they really mean aerosolized particulate lead?
- gjsman-1000 3y ago
  Perhaps, but is generally accepted that as long as you aren’t soldering at ludicrous temperatures, the quantities are very small.
  - ip26 3y ago
    On the other hand, we keep finding deleterious effects from smaller and smaller lead exposure levels.
  - tristor 3y ago
    When I was taking electronics training, my soldering instructor told me most of the lead exposure was that people used to lick the tip of their soldering iron before starting heating it up, and this exposed them to lead. Now most people don't do that, but older solderers are a little... off, if you've ever met any. Rosin flux fumes are also bad and you should definitely be working under a fume hood if you do any significant amounts of soldering, even at home.
  - rolandog 3y ago
    Well, we thought the same thing about aluminum [0]. [0]: https://hero.epa.gov/hero/index.cfm/reference/details/reference_id/518577 https://hero.epa.gov/hero/index.cfm/reference/details/refere... "Exposure, bioavailability, distribution and excretion of aluminum and its toxicological relevance to humans"
- sokoloff 3y ago
  They might mean that, but they'd still be wrong. Soldering is done around 75-100°C lower than temperatures where lead is anything other than melted in meaningful quantities. There is ingestion risk of lead residue on fingers (which is the reason why eating and smoking is prohibited around soldering stations), but very low inhalation risk.
- 3y ago
mk_stjames 3y ago
It's completely an incorrect statement and this has been studied at great lengths any place there is molten lead / lead alloys. At normal atmospheric pressure, lead does not boil until over 1700 degrees C. These people constantly mistake melting point with boiling point. Unless you have very low partial pressures, there is no lead being gassed off when you melt lead at normal liquid lead temperatures. When people 'smell' something when soldering or pouring molten lead, the are smelling aeromatics that are gassing off the materials, not lead particles suspended in air. The overwhelming danger, and the reason so many people who did work with lead back in the day have high blood levels of lead, is simple contact via their hands with the materials. This guy was likely picking up lead lines, lead ingots to melt, leaded solder all day and then not washing his hands before eating lunch, or rubbing his eyes, etc. In rare cases dust with lead particles could have been inhaled but this is even pretty rare unless they were literally belt sanding lead alloy metals in an enclosed space.
- mlyle 3y ago
  > At normal atmospheric pressure, lead does not boil until over 1700 degrees C. This argument is fallacious. It is not 100C in my house, but water is evaporating and water vapor is in the air; the air is 40% saturated with water vapor. The vapor pressure of lead is pretty low at typical soldering temperatures, though.
  - hammock 3y ago
    Notwithstanding the vapor pressure, there are other ways non-boiling lead can make it into the air. Lead-core candlewicks are well studied and put tons of lead into the air as the candle burns at 500C or less
- deleted 3y ago
  [deleted]

ghouse 3y ago

The CDC believes that: "Lead fumes are produced during metal processing when metal is heated or soldered." https://www.cdc.gov/niosh/topics/lead/workerinfo.htm https://www.cdc.gov/niosh/topics/lead/workerinfo.htm

gjsman-1000 3y ago
I am admittedly talking about electrical soldering, which the person quoted was also referring to, but there are different kinds. You would need to set your solder gun to about (edit 750, not 1100) degrees Fahrenheit to begin truly vaporizing the lead. Which, some soldering irons are capable of, but lead solder’s lower melting point of about 400 degrees makes the risk low. https://news.ycombinator.com/item?id=30629580 https://news.ycombinator.com/item?id=30629580
Gordonjcp 3y ago
The CDC believes a lot of fairly bonkers stuff that does not match up to reality. If you heated solder up to the point that lead was boiling off, your circuit board would be on fire. You cannot get lead poisoning from using leaded solder.
- AlgorithmicTime 3y ago
  I mean if you start licking it or chewing it you might, but normal usage just wash your hands afterward and you're fine.
  - Gordonjcp 3y ago
    You'd have to eat a lot of solder. Metallic lead reacts with fuck all, basically, which is why it's such a good material for things like roof flashing. It doesn't even react particularly with the hydrochloric acid in your stomach, producing only lead chloride (which will make its way out of your body fairly quickly) and hydrogen gas (not enough to do anything fun if you burp while smoking a cigarette, but let's not take chances eh). Metallic lead is about as bioavailable as sand. No no, if you want to get lead into your system you've got to really try quite hard. Taking some lead and mixing it with tin won't get the job done, oh no, not even a little bit. You're going to want to make it into an organic salt, maybe by welding on a lovely big acetate and then getting that into your stomach. Now why would you want to do a thing like that? Well, you might be an ancient Roman, with a fondness for "defrutum", a sweet sticky confection made by boiling soured wine and grapes in a lead pot until all the water is driven off. The acetic acid rips lead out like nobody's business and gets well and truly stuck together. Oh, and it tastes really sweet too, this lead acetate, which is just the thing to liven up any Roman party if the wine's gone a bit funny in the sun. Now you've got a lovely big sugar that your digestive system will happily squish into your sensitive tissues, where it'll break up and be on its way leaving a big fat lead atom right there with nothing to bind to, until it finds something. Oh hey, you know that sugars - even with a great big lead atom weighing them down - cross the blood-brain barrier just fine, right? You couldn't design a better way to get lead poisoning. Now toss in some ergot mould because you won't eat the local wheat because everyone is going mad from something and it must be those wily locals poisoning you so you only eat rye shipped over from Rome in mouldy sacks, and pretty soon - between the brain damage from lead acetate and the hallucinogenic mould - you're ready to turn horses into senators, and tell your soldiers to blunder into midgie-infested marshes in the North of Scotland where they sink out of sight never to be seen again. Lovely.

singlow 3y ago

Maybe they really mean aerosolized particulate lead?

gjsman-1000 3y ago
Perhaps, but is generally accepted that as long as you aren’t soldering at ludicrous temperatures, the quantities are very small.
- ip26 3y ago
  On the other hand, we keep finding deleterious effects from smaller and smaller lead exposure levels.
- tristor 3y ago
  When I was taking electronics training, my soldering instructor told me most of the lead exposure was that people used to lick the tip of their soldering iron before starting heating it up, and this exposed them to lead. Now most people don't do that, but older solderers are a little... off, if you've ever met any. Rosin flux fumes are also bad and you should definitely be working under a fume hood if you do any significant amounts of soldering, even at home.
- rolandog 3y ago
  Well, we thought the same thing about aluminum [0]. [0]: https://hero.epa.gov/hero/index.cfm/reference/details/reference_id/518577 https://hero.epa.gov/hero/index.cfm/reference/details/refere... "Exposure, bioavailability, distribution and excretion of aluminum and its toxicological relevance to humans"
sokoloff 3y ago
They might mean that, but they'd still be wrong. Soldering is done around 75-100°C lower than temperatures where lead is anything other than melted in meaningful quantities. There is ingestion risk of lead residue on fingers (which is the reason why eating and smoking is prohibited around soldering stations), but very low inhalation risk.
3y ago

mk_stjames 3y ago

It's completely an incorrect statement and this has been studied at great lengths any place there is molten lead / lead alloys. At normal atmospheric pressure, lead does not boil until over 1700 degrees C. These people constantly mistake melting point with boiling point. Unless you have very low partial pressures, there is no lead being gassed off when you melt lead at normal liquid lead temperatures. When people 'smell' something when soldering or pouring molten lead, the are smelling aeromatics that are gassing off the materials, not lead particles suspended in air. The overwhelming danger, and the reason so many people who did work with lead back in the day have high blood levels of lead, is simple contact via their hands with the materials. This guy was likely picking up lead lines, lead ingots to melt, leaded solder all day and then not washing his hands before eating lunch, or rubbing his eyes, etc. In rare cases dust with lead particles could have been inhaled but this is even pretty rare unless they were literally belt sanding lead alloy metals in an enclosed space.

mlyle 3y ago
> At normal atmospheric pressure, lead does not boil until over 1700 degrees C. This argument is fallacious. It is not 100C in my house, but water is evaporating and water vapor is in the air; the air is 40% saturated with water vapor. The vapor pressure of lead is pretty low at typical soldering temperatures, though.
- hammock 3y ago
  Notwithstanding the vapor pressure, there are other ways non-boiling lead can make it into the air. Lead-core candlewicks are well studied and put tons of lead into the air as the candle burns at 500C or less
deleted 3y ago
[deleted]