Author Topic: Is 'indirect' contact with lead solder safe?  (Read 7857 times)

0 Members and 1 Guest are viewing this topic.

Offline jotwerdeTopic starter

  • Contributor
  • Posts: 18
  • Country: bg
Is 'indirect' contact with lead solder safe?
« on: November 24, 2018, 06:52:06 am »
Let's say someone solders with lead solder in a room. He doesn't clean up very well and leaves some solder residue lying on the floor.
Then, something is placed on the floor, say, a book, which touches the solder left on the floor/comes into contact with it.
Then, someone else grabs the book, which has touched the lying around solder, and reads it, coming into contact with the 'solder/lead-contaminated' book.
Now, when touching food without washing hands, is the second person at risk of getting lead into his mouth?

This is similar to coughing on your hand when sick, touching a door handle with said hand, someone else touching the same handle, eating without washing their hands and getting the bacteria of the sick one into their mouth.
 

Offline Ian.M

  • Super Contributor
  • ***
  • Posts: 13216
Re: Is 'indirect' contact with lead solder safe?
« Reply #1 on: November 24, 2018, 07:31:44 am »
Bacteria and viruses (at least in cells) are alive, they propagate and the population grows exponentially if conditions are favourable.

Lead and its compounds are mineral, they don't grow.   The question therefore is: How much contamination actually gets transferred to the second person's hands and then ingested, and is it significant in relation to permissible exposure limits?
« Last Edit: November 24, 2018, 07:33:29 am by Ian.M »
 
The following users thanked this post: jotwerde

Offline BradC

  • Super Contributor
  • ***
  • Posts: 2129
  • Country: au
Re: Is 'indirect' contact with lead solder safe?
« Reply #2 on: November 24, 2018, 07:33:01 am »
If you read my books you'll find notes and annotations made with solder. 60/40 will sub as a pencil when you can't find one.
 
The following users thanked this post: jotwerde

Offline Rerouter

  • Super Contributor
  • ***
  • Posts: 4705
  • Country: au
  • Question Everything... Except This Statement
Re: Is 'indirect' contact with lead solder safe?
« Reply #3 on: November 24, 2018, 08:20:22 am »
From point contact with lead, (e.g. many little balls of solder, scattered on a table, there mostly spheres so only a tiny area makes contact), barely any ends up transferring,

As someone who works on circuit boards and solders just about every day with leaded solder, I can say the fumes are much more harmful, Wash your hands before you eat and it will likely not contribute a measurable level even after years in.
 
The following users thanked this post: jotwerde

Offline Leiothrix

  • Regular Contributor
  • *
  • Posts: 134
  • Country: au
Re: Is 'indirect' contact with lead solder safe?
« Reply #4 on: November 24, 2018, 10:45:49 am »
Ugh.  Even eating the solder is safer than you might think.

The fumes from the flux can be harmful; and are sensitizing so they can cause problems over time.

Lead is bad for sure, especially as a child.  As an adult you pretty much have to be trying before you'll have a problem.  Wash you hands after handling it, don't eat it, you'll be fine.
 
The following users thanked this post: jotwerde

Offline GreyWoolfe

  • Supporter
  • ****
  • Posts: 3652
  • Country: us
  • NW0LF
Re: Is 'indirect' contact with lead solder safe?
« Reply #5 on: November 24, 2018, 01:26:31 pm »
Ugh.  Even eating the solder is safer than you might think.

The fumes from the flux can be harmful; and are sensitizing so they can cause problems over time.

Lead is bad for sure, especially as a child.  As an adult you pretty much have to be trying before you'll have a problem.  Wash you hands after handling it, don't eat it, you'll be fine.

I tend to solder with nitrile gloves on.  Keeps hands clean from flux residue also.  I am not the cleanest solderer.  After I clean up the board, gloves in trash, clean hands, no worries.
"Heaven has been described as the place that once you get there all the dogs you ever loved run up to greet you."
 
The following users thanked this post: jotwerde

Offline jotwerdeTopic starter

  • Contributor
  • Posts: 18
  • Country: bg
Re: Is 'indirect' contact with lead solder safe?
« Reply #6 on: November 24, 2018, 03:49:19 pm »
Thanks, everyone.

I worried about this quite a bit after reading the manual of a heat gun, which stated that "one shouldn't eat, smoke or drink in a lead contaminated room" and that "lead causes irreversible brain damage". Considering that I solder in my bedroom, this made me a bit anxious and I came to think of this question, as there sure are some lead solder balls I've overlooked lying around in it. Kinda thought I underestimated the danger, one could say. As it turns out, I rather panicked.
 

Offline jmelson

  • Super Contributor
  • ***
  • Posts: 2851
  • Country: us
Re: Is 'indirect' contact with lead solder safe?
« Reply #7 on: November 24, 2018, 04:35:32 pm »
Lead solder is not all that toxic.  A good idea to wash your hands, especially before eating, and to clean up solder residue, especially after using desoldering equipment, that can make a fine dust of it.  But, really, people have been using lead solder for centuries, and the amounts used for electronics are quite minimal.  Now, lead-lined water pipes are a whole different story.

I've been using lead solder for almost 60 years, and not been super-careful with it.  As far as i know, I have no effects from that.

Jon
 
The following users thanked this post: Vtile, jotwerde

Offline jmelson

  • Super Contributor
  • ***
  • Posts: 2851
  • Country: us
Re: Is 'indirect' contact with lead solder safe?
« Reply #8 on: November 24, 2018, 04:39:28 pm »
Thanks, everyone.

I worried about this quite a bit after reading the manual of a heat gun, which stated that "one shouldn't eat, smoke or drink in a lead contaminated room" and that "lead causes irreversible brain damage". Considering that I solder in my bedroom, this made me a bit anxious and I came to think of this question, as there sure are some lead solder balls I've overlooked lying around in it. Kinda thought I underestimated the danger, one could say. As it turns out, I rather panicked.
AHH, that is different!  Heat guns are used by idiots to remove lead-based paint from houses.  That is a totally different form of lead compound, NOT just lead and tin.  It is much more easily absorbed by the body in that form.  I say idiots, because if they are not idiots going in, they WILL be after using a heat gun on lead paint indoors.  So, this is totally different than soldering.

Jon
 
The following users thanked this post: jotwerde

Offline Alex Eisenhut

  • Super Contributor
  • ***
  • Posts: 3549
  • Country: ca
  • Place text here.
Re: Is 'indirect' contact with lead solder safe?
« Reply #9 on: November 24, 2018, 06:26:19 pm »
 |O

Good grief, if lead was as deadly as anthrax, all air pistol users would be dead within days, don't you think?

I handle hundreds of .177 pellets WITH NO GLOVES on the weekends!

Oh no!!!

Hoarder of 8-bit Commodore relics and 1960s Tektronix 500-series stuff. Unconventional interior decorator.
 
The following users thanked this post: Vtile, jotwerde

Offline Vtile

  • Super Contributor
  • ***
  • Posts: 1146
  • Country: fi
  • Ingineer
Re: Is 'indirect' contact with lead solder safe?
« Reply #10 on: November 24, 2018, 10:05:18 pm »
Yes. People are jumping on the wall with the lead these days. Mind you the gasoline were leaded in the days even then most people weren't zombies in their 20s.
 
The following users thanked this post: jotwerde

Offline d_brennen

  • Newbie
  • Posts: 3
  • Country: gb
Re: Is 'indirect' contact with lead solder safe?
« Reply #11 on: November 24, 2018, 10:59:47 pm »
As AvE always says, filter the smoke through a cigarette. And wash your hands
 
The following users thanked this post: jotwerde

Offline jack-daniels

  • Contributor
  • Posts: 36
  • Country: gb
Re: Is 'indirect' contact with lead solder safe?
« Reply #12 on: November 24, 2018, 11:33:10 pm »
Let's say someone solders with lead solder in a room. He doesn't clean up very well and leaves some solder residue lying on the floor.
Then, something is placed on the floor, say, a book, which touches the solder left on the floor/comes into contact with it.
Then, someone else grabs the book, which has touched the lying around solder, and reads it, coming into contact with the 'solder/lead-contaminated' book.
Now, when touching food without washing hands, is the second person at risk of getting lead into his mouth?

This is similar to coughing on your hand when sick, touching a door handle with said hand, someone else touching the same handle, eating without washing their hands and getting the bacteria of the sick one into their mouth.


You definitely don't want to watch this then!

 
The following users thanked this post: jotwerde

Offline Ian.M

  • Super Contributor
  • ***
  • Posts: 13216
Re: Is 'indirect' contact with lead solder safe?
« Reply #13 on: November 25, 2018, 12:00:08 am »
Lead pipes are safe enough as long as you have hard water and don't drink or cook with water from the hot tap.   The video doesn't mention iron pipes which are by far the commonest for the incoming supply in old properties.   Running a litre of water will flush out 8m of 1/2" pipe, so its a good idea to run a couple of litres from the kitchen tap before use if it hasn't been run that day, even for plastic pipes.  Don't drink from taps that don't have a direct mains water supply - cold header tanks are a breeding environment for all sorts of nasties and if poorly maintained tend to have dead rats and/or pigeons in the bottom!
 
The following users thanked this post: jotwerde

Offline basinstreetdesign

  • Frequent Contributor
  • **
  • Posts: 466
  • Country: ca
Re: Is 'indirect' contact with lead solder safe?
« Reply #14 on: November 25, 2018, 12:52:31 am »
Lead solder is not all that toxic.  A good idea to wash your hands, especially before eating, and to clean up solder residue, especially after using desoldering equipment, that can make a fine dust of it.  But, really, people have been using lead solder for centuries, and the amounts used for electronics are quite minimal.  Now, lead-lined water pipes are a whole different story.

I've been using lead solder for almost 60 years, and not been super-careful with it.  As far as i know, I have no effects from that.

Jon

Yeah, I've been using lead solder for a few decades and it hasn't affected me at all! (cough)
But I always wash my hands after working at the bench.  I do the cooking in our house so its pretty mandatory.  But to say eating it has no immediate affect is a stretch.  When Canada was young and the old Hudson Bay company was in the trapping business, they operated out of "camps" where their furs were warehoused and traded.  If some kids got rambunctious the camp doctor would give their parents a lump of lead for the kids to chew on!  It seemed to settle them right down! :o
STAND BACK!  I'm going to try SCIENCE!
 
The following users thanked this post: jotwerde

Offline cdev

  • Super Contributor
  • ***
  • !
  • Posts: 7350
  • Country: 00
Re: Is 'indirect' contact with lead solder safe?
« Reply #15 on: November 25, 2018, 01:57:41 am »
I wonder if sulfur soap or EDTA-soap would be better than regular soap for washing up after soldering? EDTA binds metals. And  thiols like lipoic acid, as well as sulfur-containing amino acids may help bind some metals.

Both tend to dry out the skin a bit more than most soaps.
"What the large print giveth, the small print taketh away."
 
The following users thanked this post: jotwerde

Offline Rerouter

  • Super Contributor
  • ***
  • Posts: 4705
  • Country: au
  • Question Everything... Except This Statement
Re: Is 'indirect' contact with lead solder safe?
« Reply #16 on: November 25, 2018, 02:36:23 am »
The soaps not much of an issue, just most people don't wash there hands well

https://worldwide.saraya.com/expertise/public-health-hygiene/hand-hygiene-in-public-settings

Have a look at the Wash part
 
The following users thanked this post: jotwerde

Offline jotwerdeTopic starter

  • Contributor
  • Posts: 18
  • Country: bg
Re: Is 'indirect' contact with lead solder safe?
« Reply #17 on: November 25, 2018, 08:14:59 am »
Just for clarification, when you all say 'wash your hands before eating', do you mean 'wash your hands before eating if you handled solder' or 'generally wash your hands before eating even if you haven't handled solder, because you've got solder lying around'? Taking the example from above, should the one who took the book wash his hands, even though he just touched the book and may not know that it's touched solder?

You definitely don't want to watch this then!
youtube.com/watch?v=djphiNHncTw

Feeling brave yesterday, I watched it. Aside from loosing consciousness twice while watching, I'd say I'm fine.
Just joking.
 

Offline Mechatrommer

  • Super Contributor
  • ***
  • Posts: 11714
  • Country: my
  • reassessing directives...
Re: Is 'indirect' contact with lead solder safe?
« Reply #18 on: November 25, 2018, 08:56:53 am »
i think i have brain damage from lead poisoning. you name it, inhale fume, direct contact and chewing. luckily it doesnt taste good. sarcasm off but seriously i think i have brain damage because lately i have tendency to buy higher BW stuffs from ebay, where's that TEA thread?
Nature: Evolution and the Illusion of Randomness (Stephen L. Talbott): Its now indisputable that... organisms “expertise” contextualizes its genome, and its nonsense to say that these powers are under the control of the genome being contextualized - Barbara McClintock
 

Offline Rerouter

  • Super Contributor
  • ***
  • Posts: 4705
  • Country: au
  • Question Everything... Except This Statement
Re: Is 'indirect' contact with lead solder safe?
« Reply #19 on: November 25, 2018, 09:05:09 am »
Mechatrommer, If the bandwidth is under 40GHz, then your still fine. once you have to apply correction curves for the characteristics of your probes, you start going mad.
 

Offline tggzzz

  • Super Contributor
  • ***
  • Posts: 21225
  • Country: gb
  • Numbers, not adjectives
    • Having fun doing more, with less
Re: Is 'indirect' contact with lead solder safe?
« Reply #20 on: November 25, 2018, 09:21:23 am »
Lead pipes are safe enough as long as you have hard water and don't drink or cook with water from the hot tap.   The video doesn't mention iron pipes which are by far the commonest for the incoming supply in old properties.   Running a litre of water will flush out 8m of 1/2" pipe, so its a good idea to run a couple of litres from the kitchen tap before use if it hasn't been run that day, even for plastic pipes.  Don't drink from taps that don't have a direct mains water supply - cold header tanks are a breeding environment for all sorts of nasties and if poorly maintained tend to have dead rats and/or pigeons in the bottom!

Precisely; beat me to it.

For 30 years I've lived in a house with lead pipes between the street and the internal stopcock. When I moved in I had the lead content measured as 49ug/l, just under the legal limit (limit is now 10ug/l). After running the cold water for 1 minute to clear out that pipe, the lead content was undetectable.

Hence for any cooking/drinking purposes I have run the water for 1 minute, and I was perfectly happy to bring my daughter up here.

I also keep tin/lead solder paste in my fridge, inside a syringe, inside a sealed plastic bag, inside a sealed plastic box.

I handle lead/tin solder whenever I do some soldering.

I do wash my hands after any such activities, but I'm not paranoid about it.
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
Having fun doing more, with less
 
The following users thanked this post: jotwerde

Offline jotwerdeTopic starter

  • Contributor
  • Posts: 18
  • Country: bg
Re: Is 'indirect' contact with lead solder safe?
« Reply #21 on: November 25, 2018, 02:24:53 pm »
I also keep tin/lead solder paste in my fridge, inside a syringe, inside a sealed plastic bag, inside a sealed plastic box.

This may sound stupid, but is there any particular reason for storing the solder in your fridge?
 

Offline mikeselectricstuff

  • Super Contributor
  • ***
  • Posts: 14117
  • Country: gb
    • Mike's Electric Stuff
Re: Is 'indirect' contact with lead solder safe?
« Reply #22 on: November 25, 2018, 02:36:18 pm »
I also keep tin/lead solder paste in my fridge, inside a syringe, inside a sealed plastic bag, inside a sealed plastic box.

This may sound stupid, but is there any particular reason for storing the solder in your fridge?
Solder paste lasts longer in the fridge
Youtube channel:Taking wierd stuff apart. Very apart.
Mike's Electric Stuff: High voltage, vintage electronics etc.
Day Job: Mostly LEDs
 
The following users thanked this post: jotwerde

Offline tggzzz

  • Super Contributor
  • ***
  • Posts: 21225
  • Country: gb
  • Numbers, not adjectives
    • Having fun doing more, with less
Re: Is 'indirect' contact with lead solder safe?
« Reply #23 on: November 25, 2018, 02:38:46 pm »
I also keep tin/lead solder paste in my fridge, inside a syringe, inside a sealed plastic bag, inside a sealed plastic box.

This may sound stupid, but is there any particular reason for storing the solder in your fridge?

Solder paste for SMD components contains liquid flux and has a shelf life. Being cooler extends the shelf life, but I wouldn't want to use that technique where repeatability is required.
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
Having fun doing more, with less
 
The following users thanked this post: jotwerde

Offline jotwerdeTopic starter

  • Contributor
  • Posts: 18
  • Country: bg
Re: Is 'indirect' contact with lead solder safe?
« Reply #24 on: November 25, 2018, 02:49:06 pm »
Solder paste for SMD components contains liquid flux and has a shelf life. Being cooler extends the shelf life, but I wouldn't want to use that technique where repeatability is required.

I noticed that you wrote paste, excluding it from my question was a typo.
Just asking cause there's no hint to keep it cool written on the one I've got.
Thanks for the info.
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf