How often do you wash hands after working with electrical equipment?

[Jay112]

Do you only wash your hands after handling parts that you know contain lead?

Do you always wash your hands after handling parts that you know contain lead?

Do you wash your hands after handling a lot of equipment, because most likely there was lead in there somewhere?

Do you wash your hands even if the equipment is RoHS certified?

Do you think some of the (cheaper) products labeled as RoHS certified aren't actually certified?

Is there a history of electrical engineers suffering from lead poisoning, similar to how the hat makers in the past were known to suffer from side effects of mercury poisoning (like the "Mad Hatter")?

[Monadnock]

yes, yes, no, no, don't know, not that I've heard.

 I did go for lead testing a few years back and my levels were elevated, although not enough to be a problem.

[gnavigator1007]

Somewhat ironically, I wash my hands everytime I pull myself away for a cigarette. 

[bson]

Lead doesn't turn unto vapor until over 1600C, temperatures never reached soldering.

[made2hack]

Usually when I am done for the day OR, I break for lunch, OR I break for coffee / snacks, OR, I break for the bathroom.

Unless I have used some other type of solution like adhesives, epoxy or am working on a really dusty / dirty equipment. But I also have nitrile gloves handy.

To answer your questions, none of the reasons is that I come in contact with lead solder.

[helius]

I wash my hands after handling parts at hamfests because a lot of them are just plain grimy.

Is there a history of electrical engineers suffering from lead poisoning, similar to how the hat makers in the past were known to suffer from side effects of mercury poisoning (like the "Mad Hatter")?

No, absolutely not. Lead metal is poorly absorbed by the body and very unlikely to poison anyone.
What is common with all cases of lead poisoning (from eating paint, leaching from old pipes, etc) is that they are ingesting oxides of lead, which are far more toxic.

[Zero999]

Lead doesn't turn unto vapor until over 1600C, temperatures never reached soldering.

Yes, that is true. Lead doesn't get hot enough during soldering to evaporate. I'd suspect more led is absorbed though the skin when handling lead solder.

[CatalinaWOW]

About the same amount as after any other activities.  You are far more at risk from bacteria, greases, resins, and any number of other things than from the lead.

Lead fear, like radioactivity fear is promulgated by folks who have no idea what numbers are, or how to use them.  Since they don't have this tool the choices become binary.  It is either good, or bad.  Lead which is bad when put into the air by the ton as a byproduct of combusting leaded gasoline, or in paint which might be a problem for anyone who actually eats the paint gets translated into "Lead is bad".

[helius]

Lead doesn't turn unto vapor until over 1600C, temperatures never reached soldering.

Yes, that is true. Lead doesn't get hot enough during soldering to evaporate. I'd suspect more led is absorbed though the skin when handling lead solder.

1750C is the boiling point, but what you actually care about is vapor pressure. Over 550C the vapor pressure of lead is substantial. If you use a 750C iron and dwell on joints for a long time it could be a problem, but you will know something is wrong when all your components stop working from overheating.
Lead metal is not absorbed through the skin. Even mercury is very poorly absorbed this way.

[AndyC_772]

I tend to wash my hands after handling electronics before eating - but it's nothing to do with lead, and more to do with flux residue from soldering.

[thisguy]

What is common with all cases of lead poisoning (from eating paint, leaching from old pipes, etc) is that they are ingesting oxides of lead, which are far more toxic.

My hands can be darkened from handling solder to the point that when I wash my hands, the runoff water is slightly discolored. I wonder how much of this is lead oxide. I also wonder how much could be absorbed by inadvertently rubbing my eyes or by eating snacks without washing first. I have no idea if it's a risk, or if it is, how much unwashed eye-rubbing/snack-eating I'd have to do to for it to be a significant risk.

I try to remember to wash my hands after soldering.

[Tandy]

I don't care about lead and am mad as a box of frogs as a result.

[Ysjoelfir]

I wash my hands at random occasions, like... when I feel dirty? I don`t care if the parts I handle contain lead (which most of them do as I mostly have vintage stuff around), I even hold the leaded solder with my mouth sometimes... Didn't harm me at all for now..
What really makes me feel like washing my hands is when I work with stuff that is realy dusty or sticky. I hate that.

[roffvald]

Usually when I take a bathroom break or a food break. Also use alot of moisturizer lotion as I tend to neglect gloves when slathering stuff up with IPA which dries my hands out.
Not too worried about the lead, more of a habit and to get any flux residue off.

[Mechatrommer]

sometime i chew the lead but i wash my hand at least 5 times a day... having said that, lead.. err or more precisely solder, is not in my taboo regime... reply to this 5 pages i dont care.. because i proved you wrong so far..

[Jay112]

There were so many neat and useful comments on this thread! I just wanted to thank everyone for responding!

Usually I would reply more to a thread I start, but I'm out of my league when there are so many replies by experienced folks.

[Dave]

I usually wash my hands after soldering, partly because of lead and mostly because of sticky rosin residue that gets on your fingers one way or another.

I don't feel the need to wash my hands after working with other electronic equipment, because even the used equipment (and I have a lot of it) always gets the scrubby treatment before I'm comfortable working with it. I always tear things down, fix things if they need fixing, wash them piece by piece and reassemble when dry. Last weekend I took on a grimy 33120A, now it looks like a new unit.

[IanB]

Do you only wash your hands after handling parts that you know contain lead?

Do you always wash your hands after handling parts that you know contain lead?

Do you wash your hands after handling a lot of equipment, because most likely there was lead in there somewhere?

Do you wash your hands even if the equipment is RoHS certified?

Do you think some of the (cheaper) products labeled as RoHS certified aren't actually certified?

Is there a history of electrical engineers suffering from lead poisoning, similar to how the hat makers in the past were known to suffer from side effects of mercury poisoning (like the "Mad Hatter")?

Lead is not an indicator for washing your hands. What is this crap?

You should wash your hands when they are dirty, before eating, after using the bathroom, and so on. Did your mother teach you nothing?

(By the way, I would be quite happy to suck on a lump of lead. Metallic lead is not actually very harmful.)

[Muttley Snickers]

^^^This^^^^

I remember as kid on fishing trips chewing sinkers all day long when nothing else was biting, did me no harm that I am aware of.   

[Circlotron]

I wash my hands after handling parts at hamfests because a lot of them are just plain grimy.

Yeah, those hams should spend less time in the shack and more time in the shower. 

[IanB]

I remember as kid on fishing trips chewing sinkers all day long when nothing else was biting, did me no harm that I am aware of.   

Yes, we used split shot as fishing weights and the easiest way to close a lead weight around the line was to squeeze it shut between your teeth. Quite harmless.

[German_EE]

If the equipment was dirty then I clean my hands (and the workbench) afterwards. I also wash after using WD40 as it tends to taint whatever I touch afterwards.

[Psi]

I'm always careful when using solder paste, especially when stenciling. That stuff gets all over the place.

I once handled some really old RF transistors and a few had some random powder on them.
It gave me a really bad migraine within 10min. Best theory is that the powder was probably beryllium oxide.

[Muttley Snickers]

One of my first jobs involved the installation of antenna masts and prior to the advent of silicone sealants we used a bitumen based product called Ormonoid, black as tar it was and nobody instructed me to use a stick when applying it so I used my hands instead, sticks like shit to a blanket.

Similar can as this.

[KL27x]

I know guys that use lead-free when they aren't required to for fear of lead.

I know a guy that holds solderwire in his mouth while working.

Me, I wash my fingers and equipment quite frequently, simply because I can't stand my own finger oils. I'm not particularly paranoid about lead. I just try to not touch my eyes or mouth while working and to wash before I eat.

[Whales]

I wash my hands after handling electronics, regardless of whether I think they're leaded or not.  If I only ever handled clean electronics then my only concern would be ingesting heavy metals, but I also handle burned/failed and elderly electronics too. 

[coppice]

You should wash your hands after handling electronics, but its lead content is largely irrelevant. The lead generally stays where it is. However, flux, seepage from capacitors, and various breakdown products from ageing components can be quite nasty.

[BurningTantalum]

It's supermarket trollies that really bother me...
My bench only has MY dirt on it.

BT

[Psi]

I know guys that use lead-free when they aren't required to for fear of lead.

LOL, the flux in the lead free stuff is far worse than leaded+rosin

[Whales]

What are our sources for all of this information?

[MadModder]

The first question is kind of funny. Only after handling lead, but for example never after a visit to the toilet? 

I wash my hands when they are visibly dirty, and when I know I have touched something that I would never put my mouth on.
And when I am about to handle something that must not get dirty fingerprints.
I don't think I have ever washed my hands after using leaded solder or using my old equipment full of wonderful leaded solder, if they're not visibly dirty.
I guess I just forget.
It's far worse inhaling the flux fumes in my opinion, than getting a minuscule amount of leaked electrolyte on your tongue.
For those that do not know, the taste is quite bitter. Like denatured alcohol... :p

[Jay112]

I do appreciate the humor on this thread, including taking the word "only" literally, and also about washing the hands before smoking cigarettes.

I also would like to see some more sources for some of this information. I'll probably do a little studying here and there on some of the things mentioned above, and I'll share links if I find them useful.

I thought this stackexchange answer was very thorough:
http://electronics.stackexchange.com/a/19086/83333
(The top answer, with 53 votes).

[Jay112]

This was a good paragraph:

Rosin cored solder fume is a well established respiratory sensitiser, and is one of the main causes of occupational asthma in Great Britain. Colophony fume is generated at temperatures above about 180 C, well below the temperatures associated with soft soldering. So significant concentrations can be evolved. The higher the temperature, the more fume is generated.  The lead free solders introduced since the Restriction of Hazardous Substances Directive was implemented in 2006 tend to have higher melting points than the traditional lead:tin types. So, ironically, the elimination of lead for environmental reasons has led to a potential for increased exposures to a potent asthmagen in the workplace.

https://diamondenv.wordpress.com/2011/01/06/lead-exposure-during-soldering/

[AndyC_772]

What are our sources for all of this information?

Have you learned nothing? This the internet!

Nobody needs actual sources for information, 'trusty' meters don't need checking or calibrating, and no person has ever actually derived practical benefit from something they learned on a degree course.

[Jay112]

The following page had some neat info that I'll quote below: http://store.curiousinventor.com/guides/how_to_solder/kind_of_solder
It also was well referenced.

Lead boils at over 3000 °F, and in most cases soldering tips should be kept below 750 °F, so it is highly unlikely that gaseous lead is present in the fumes. The fumes are actually from the flux boiling, which still isn't great for you--many of the chemicals found in cigarette smoke are found in flux fumes: formaldehyde, toluene, alcohols, and hydrochloric acid to name a few. Most of the public health literature indicates that asthma is the major health risk from soldering fumes (not cancer or lead poisoning). When acquired, it is permanent and can cause hyper sensitivity so that even small amounts of fumes bring on attacks. Surprisingly, scientists have not been able to determine what exactly in the fumes cause the health defects, nor what amounts are harmful. Yet, the British health department has set exposure limits of .05 mg/m^3 over 8 hours and .15 mg/m^3 over 15 minutes. I believe these limits have been shown to provide a safe work environment and also one for which the necessary systems / filters are financially reasonable.

The conspicuous lack of emphasis on lead poisoning in all the research done by the UK health department implies that these particles are of little concern.

It had a link to a Weller page that said that lead-free solder fumes are more toxic and require better ventilation, but the page doesn't seem to exist at that address anymore.

[CatalinaWOW]

For those who want scholarly justification try some of the following.

http://jama.jamanetwork.com/article.aspx?articleid=256412
This is a widely cited paper on the epidemiology of lead poisoning.  In the first page summary (which is free) are several pertinent facts about lead poisoning.

https://www.cdph.ca.gov/programs/olppp/Documents/medgdln.pdf
Good summary of health effects, ingestion paths and efficiencies.  No direct information on typical exposure in electronics work.

http://www.aafp.org/afp/1998/0215/p719.html
This has a list purported to be the industries most associated with overexposure to lead.  Electronics use of solder is not on the list, but there is no quantitative evidence backing the list.

http://www.hse.gov.uk/statistics/causdis/lead/lead.pdf
This shows blood levels in industries which Britain regards as significant exposures to lead.  You can put the information together to show that even in the worst industries (smelting lead for example) exposures are marginally acceptable.  Electronics does not show explicitly in the list, though it may crop up in the "other" category. 

After reading through these and others I remain convinced that solder is low on the list of hazards we face.  Don't eat it.  Don't sweep your bench onto your meal.  Staying away from the flux fumes will keep you safe enough from the lead vapor.

[Tandy]

AFIK the main reason for removal of lead from electronics was primarily an attempt to keep lead out of the water table from landfill. While it is a good thing to reduce exposure to harmful substances often the risks are grossly overstated by people who don't have the full facts. I love in a house built in the 1930's and the water company will not replace the lead pipes that supply water to the house because the amount of lead is considered within safe limits.

We used to have multiple sources of lead in fairly high doses particularly from leaded fuel, but now most sources of lead exposure have gone, fuel, paint, plumbing are all lead free now and children aren't sucking on miniature lead soldiers any more. My personal take on it is that a typical hobbyist use of lead solder and components isn't going to have any significant impact. However in order to comply with safety rules the lead solder we sell has to carry advice to wash your hands simply because we live in a world where the lawyers are in control.

Chances are that the cleaning products that you use to try and keep yourself and your home clean and smelling 'nice' are causing you more harm. Volatile organic compounds in fragranced products have been shown to cause damage to DNA.

[Cerebus]

Lead doesn't turn unto vapor until over 1600C, temperatures never reached soldering.

No, lead can exist only as a gas/vapour above its boiling point (2022K, 1746C) but that doesn't mean that lead vapour doesn't exist below that temperature. Just as water vapour exists between its freezing point (strictly triple point) and its 100C boiling point.

I can't find a phase diagram for Lead or a Lead-Tin eutectic alloy that extends high enough in temperature to show the vapour phase, but it's there. I can tell you that the melting point of lead is 600K (327C) and the vapour pressure of lead is 1 Pa by 978K (705C) and keeps going up until it reaches ~100kPa at boiling point. If you compare the vapour pressure with that of any of the gases that make up air (including water vapour) it's pretty clear that the absolute quantity of lead vapour that could drift off into the air from molten solder at temperatures compatible with life is tiny but to say it doesn't exist is, strictly, incorrect.

[Cerebus]

I spent too long at school and university in laboratories to have anything other than an instinctive handwashing reflex if I've been involved in any activity that might conceivably, possibly resulted in me picking up anything one might describe as contamination. Microbiology labs are the best training for this - it's not the possibility of contaminating yourself that matters so much as that you might contaminate what you're working on and render your efforts to date worthless.

So electronics attracts no more or less handwashing, for me, than any other activity.

About the same amount as after any other activities.  You are far more at risk from bacteria, greases, resins, and any number of other things than from the lead.

Idiots. You missed idiots from the list, by far the most dangerous thing in my opinion.

Lead fear, like radioactivity fear is promulgated by folks who have no idea what numbers are, or how to use them.  Since they don't have this tool the choices become binary.  It is either good, or bad.  Lead which is bad when put into the air by the ton as a byproduct of combusting leaded gasoline, or in paint which might be a problem for anyone who actually eats the paint gets translated into "Lead is bad".

I'm pretty much convinced that the harm done to your health by worrying about the things people, particularly the Daily Mail¹, tell you to fear as threats to your health does more harm than all the ostensible threats put together.

[Editted to add:] I can smell the Hasselback potatoes baking in the kitchen over which I have just poured a mixture of

• Olive oil - apparently supposed to make me live forever.
• Butter - apparently this will kill me.
• Rosemary - full of Volatile Organic Components which surely are the devil incarnate

As to what the Daily Mail would have to say about the sausages, peas, Italian carrots and gravy that is going with these I dread to think.

¹ The Daily Mail is a tabloid, right wing British daily national newspaper catering to the middle aged of middle England which can't go a day without publishing a headline that "X causes cancer", or some other left field, baseless, and marginal health claim or health fear. Political rather than medical problems are all blamed on immigrants and foreigners (Daily Mail code for anyone who's not got pasty white middle English skin). Substitute your local equivalent.

[helius]

One of my first jobs involved the installation of antenna masts and prior to the advent of silicone sealants we used a bitumen based product called Ormonoid, black as tar it was and nobody instructed me to use a stick when applying it so I used my hands instead, sticks like shit to a blanket.

I recently patched some pavement with a similar product that contained asphaltum. Not only was it extremely sticky, but it also smelled like cat piss. I resorted to using naphtha to clean it off my hands.
There are antiseptics made of coal tar ("ichthammol") which while looking very similar are actually not that sticky.

[Audioguru]

Maybe medical people were worried that pregnant ladies were soldering and eating the lead in solder? I am a guy and I worked with leaded solder all my life and I never got lead poisoning because I never ate the stuff. For many years copper water pipes were soldered together with leaded solder and nobody got lead poisoning. My drinking water comes from a lake that has lead down there and nobody is poisoned. 

[bson]

By the way, you can get poisoned by silver also.  Yet it's used for utensils; in fact I just spent a few hours polishing a bunch.  No signs of poisoning yet... 

[Jay112]

By the way, you can get poisoned by silver also.  Yet it's used for utensils; in fact I just spent a few hours polishing a bunch.  No signs of poisoning yet... 

I believe this is different because it takes a much higher intake of silver to get poisoned. People die every year in the USA from drinking too much water too, but generally it would be very difficult for someone to be able to drink that amount without trying hard. Whereas with something like lead, we know that children can get seriously harmed by it from playing in contaminated dirt and not washing their hands before eating. The amount of lead on their hands is miniscule and invisible, yet it still poisons them.

Also, I just wanted to mention that the common argument that "I've done such-and-such for years, but it hasn't harmed me" isn't good science, since lots of people can say the same thing about smoking cigarettes as well. My grandpa chain-smoked every day of his adult life and lived happily and healthily until the age of 95. I used to be a smoker for years too, and noticed no negative consequences on myself, but that doesn't mean that smoking is safe nor that it doesn't harm other people.

I don't think anyone here was relying on such arguments as their sole evidence, and I think it's still useful to share information like that, but it should be used with the rest of the available evidence.

[IanB]

Whereas with something like lead, we know that children can get seriously harmed by it from playing in contaminated dirt and not washing their hands before eating. The amount of lead on their hands is miniscule and invisible, yet it still poisons them.

Do you have a reference for that? How do "we" know that such is the case?

[Jay112]

Whereas with something like lead, we know that children can get seriously harmed by it from playing in contaminated dirt and not washing their hands before eating. The amount of lead on their hands is miniscule and invisible, yet it still poisons them.

Do you have a reference for that? How do "we" know that such is the case?

The topic of childhood lead poisoning is non-controversial, with every major health organization in the world agreeing on the causes and effects. Of course this doesn't mean that the information they're asserting is correct, but that does give me freedom to say that "we know" this, since there is a general consensus on the data. It's similar to saying that "we know" cigarettes are harmful.

Since there are countless studies and references that show how harmful lead exposure is to children, it feels silly to make a list of them. But here's one from the World Health Organization that is a good summary:
http://www.who.int/ceh/publications/leadguidance.pdf

Here is a quote from that document about what I wrote above, but please read the entire document before complaining about this specific quote:

Ingestion is the most common route of exposure to lead for children. Once
lead has been swallowed, it enters a child’s body by absorption from the
gastrointestinal tract. Children’s innate curiosity and their age-appropriate
hand-to-mouth behaviour result in their bringing lead-containing or leadcoated
objects, such as contaminated soil or dust, to their mouth, and
thus greatly increase their risk of exposure.

Would anyone like to provide some sources that say it's safe for children to ingest lead? Good luck finding them.

[GreyWoolfe]

[Editted to add:] I can smell the Hasselback potatoes baking in the kitchen over which I have just poured a mixture of

• Olive oil - apparently supposed to make me live forever.
• Butter - apparently this will kill me.
• Rosemary - full of Volatile Organic Components which surely are the devil incarnate

Shame on you, you forgot the garlic

[IanB]

The topic of childhood lead poisoning is non-controversial, with every major health organization in the world agreeing on the causes and effects. Of course this doesn't mean that the information they're asserting is correct, but that does give me freedom to say that "we know" this, since there is a general consensus on the data. It's similar to saying that "we know" cigarettes are harmful.

From the context of your comment you made it sound like lead is a major environmental hazard that children everywhere will become exposed to. Yes, lead ingestion is harmful, but I don't believe the average child playing in average dirt will become exposed to lead poisoning.

[CatalinaWOW]

I went off and put together the following chart using various sources.  There are flaws in some of the sources and assumptions, but I think it is close to correct.  The point is that vapor pressure is not the critical factor, as that determines the equilibrium.  We never reach equilibrium in our labs.  The evaporated lead cools immediately and has no effect on whether more lead comes out of the joint.  The graph is based on evaporation rate, and plots the amount of lead put into the air per second for a typical solder joint.  If all of this lead were transmitted into you it would be the dose you get from soldering.  But only a fraction of that will end up in you, depending on your ventilation, size of lab, how close your face is to the work and many other factors.  Your lifetime limit on lead collection to keep your blood below the accepted range is pretty tiny, about 20 milligrams.  Using values from the chart and assuming that all of the evaporated lead ends up in you, if you keep your iron cool (350C), you can solder for about half a million hours before getting your 20 milligram dose.  Hard to do in one lifetime. If you really run your iron hot (550C) you need to pay attention to ventilation and other hygiene practices as the dose could be achieved in under 20 hours of soldering.

This is all consistent with the anecdotal information most people here have related.  If there were a extremely serious problem with this lead exposure there would be many reports of problems.  Not like the cigarette case where there are huge numbers of observed lung cancers to go with the admittedly large number of people who live a long life of smoking with minimal problems.

[Jay112]

@CatalinaWOW: Thank you so much for your helpful and informational posts. I just wanted to note, (not that you were accusing me of this), that I don't personally think the lead-solder case is anything like the cigarettes case, and that whenever I had mentioned cigarettes it was for contrast. I completely agree with you that the lead-soldering case is opposite of the cigarette case, since the bulk of the evidence shows that soldering with lead is generally safe.

I think it's very evident from the information shared here that the biggest danger when soldering is from inhaling the fumes from the flux. Some people took that to mean that lead poisoning isn't a problem in this country, which I disagree with, since the WHO document I linked to says the damages from lead poisonong in the US cost society over $40 billion per year. But obviously most of that poisoning is from other sources besides solder, and it seems that even the official health organizations recognize that.

I think this was a high quality thread, and I thank everyone for their contributions.

[CatalinaWOW]

One final note.  All of the literature indicates that lead is far more dangerous to juveniles.  The recommended exposure levels are at least a factor of four lower, and the consequences of minor poisoning are more severe.  Those raising or advising children (cutoff is a little unclear but definitely for the under 10 group, probably should carry on to 17 or more years) should use extra care on solder exposure.

[Cerebus]

If you really run your iron hot (550C) you need to pay attention to ventilation and other hygiene practices as the dose could be achieved in under 20 hours of soldering.

Excellent work that man!

The quantities at higher temperatures really surprise me, as being higher than I'd have imagined. And while this poses no practical risk to us with our puny irons and tiny joints I wonder what it means for plumbers with big hot propane or MAPP torches?

[Jay112]

That's a good point about the plumbers. It's interesting that Wikipedia lists plumbing as one of the risky jobs:
https://en.wikipedia.org/wiki/en/Lead_poisoning

In addition, lead miners and smelters, plumbers and fitters, auto mechanics, glass manufacturers, construction workers, battery manufacturers and recyclers, firing range instructors, and plastic manufacturers are at risk for lead exposure.[71]

This is an amazing quote from the same paragraph:

Parents who are exposed to lead in the workplace can bring lead dust home on clothes or skin and expose their children.[78]

[Mr.B]

That's a good point about the plumbers. It's interesting that Wikipedia lists plumbing as one of the risky jobs:

Most plumbers these days wouldn't know what copper pipe and solder was.
I think they are more at risk from the solvents used in PVC pipe cement than lead...

[helius]

At higher temperatures (>550C), lead fumes are not the only concern. Many other metals such as nickel and zinc are a health hazard when heated during casting, brazing, or welding operations.

[Cerebus]

That's a good point about the plumbers. It's interesting that Wikipedia lists plumbing as one of the risky jobs:

Most plumbers these days wouldn't know what copper pipe and solder was.
I think they are more at risk from the solvents used in PVC pipe cement than lead...

At this point I'd pass you over, if she was here, to my ex-wife who once worked in the reproductive toxicology research group at ICI who could tell you all the nasty things paint and glue solvents and adjuvants can do to your 'gentleman parts'. Take home point - don't put paint or solvent rags in your trouser pockets.

[edy]

What about washing BEFORE handling electronic equipment? I am worried about oil from the skin causing issues, like when they say to use gloves when changing halogen bulbs. Thoughts?

[Cerebus]

What about washing BEFORE handling electronic equipment? I am worried about oil from the skin causing issues, like when they say to use gloves when changing halogen bulbs. Thoughts?

It definitely matters if you're dealing with the sensitive high impedance parts on test equipment, hence the plethora of guard rings in electrometers and the like. Washing your hands won't help with these much though as you'll replace the oils on your skin within a few minutes of washing them - careful handing and gloves are the way to go here.

[3db]

Somewhat ironically, I wash my hands everytime I pull myself away for a cigarette.

Classic 

[csmithdoteu]

I wash all the time, before and after. Firstly, the human body is dirty and greasy. Look at a bit of copper clad after I've been using it for 10 minutes:



Secondly, I noticed something a couple of years ago when watching a video of Jim Williams repairing a scope, that he licked the solder before he used it. I'm wondering if that his Alzheimer's was linked to this habit in some way.

[hibone]

Detective Monk's thread I guess. 

If one is not careful enough may end thinking that birth is a fatal illness. No one has ever survived.

[N2IXK]

Well, life itself is a 100% fatal, sexually transmitted disease, after all.....

[djacobow]

^^^This^^^^

I remember as kid on fishing trips chewing sinkers all day long when nothing else was biting, did me no harm that I am aware of.   

Double this.

Same boat here. I used to chew on sinkers and always used my teeth to tighten them into the line.

Not saying I'm not brain damaged, but I don't feel brain damaged. :-)

[djacobow]

I know a guy that holds solderwire in his mouth while working.

BTDT. Sometimes you need a third hand!

[VK5RC]

I would be just a bit careful with solder or solder dust,  while lead is pretty insoluble at room temperature,  the stomach (pH approx 1) I suspect may be quite good at converting it to a lead salt, which may then be soluble (i don't know for sure).
The only study I know has looked at keen builder type Hams and not found elevated blood lead in a semi-random sample.  Erich Heinzle VK5HSE wrote this up in the September quarter of QEX.
The state where I live has a town that smelts (Port Pirie) a significant proportion of the world's lead,  the soil in that town is contaminated and good studies have shown the drop in IQ related to blood lead levels. While the smelter has given many work it has also indirectly maimed many generations.
Lead in soil levels is also raised next to busy roads (residual lead from leaded petrol).
I think a bit of common sense is all that is needed. 
Interesting re the flux vapours,  I have a sneaking suspicion re plasticisers from cable insulation (but no evidence).

[chris_leyson]

To be honest, I would be more worried about Lithiun than Lead. Batteries going into landfill, water table etc.

[Whales]

Hmm.  So far we know:

• Lead (atleast on its own) is toxic
• Flux smoke can cause respiratory issues
• Lead does not evaporate at normal soldering temperatures
• Electronics & soldering involves hazards other than lead and flux.

We have also found investigations into:

• Lead exposure from non-soldering professions
• Hazards other than lead from soldering
• Effects of lead on people
• Lists of professions where lead contact is likely

Does anyone know of any investigations into "exposure to lead through soldering" or "exposure to lead through electronics work"?  I'm beginning to believe this has not been investigated/results have not been published.

This source linked by Jay112 has some second-hand information about an investigation in a workplace RE lead exposure in workers due to soldering, concluding they had negligible lead exposure.  Does anyone know where this investigation was done/if there are any more details available?''

Something I have heard IRL and online is that "lead-tin solders are not absorbable in the body".  Does anyone know of evidence relating to this?

[CatalinaWOW]

The only evidence I have contradicts the statement that solder is not absorbed.  See the following.

https://www.nlm.nih.gov/medlineplus/ency/article/002822.htm

The article suggests that solder will poison you if you do something really stupid - eating large amounts of solder.  This is consistent with the reports of waterfowl being poisoned by eating lead shot, and also consistent with the reports here of biting (but not swallowing) lead sinkers without bad outcomes.

As for specific exposure to lead during soldering you might consider the following - a health examination of an manufacturing operation that runs both wave soldering lines and solder paste heat reflow lines.

https://www.cdc.gov/niosh/hhe/reports/pdfs/2007-0201-3086.pdf

You can compare it to your own soldering to see if you are concerned, but the CDC did not find anything particularly worrisome in the evaluation.   It is worthy of note that they found lead on the workers hands even after hand washing.  But it is also worth thinking about how lead that can't be removed by handwashing will somehow wipe off onto food and get into your mouth where it might be harmful.

There should be lots more information of this type at the following location

https://www.osha.gov/opengov/healthsamples.html#download

[Whales]

It is worthy of note that they found lead on the workers hands even after hand washing.  But it is also worth thinking about how lead that can't be removed by handwashing will somehow wipe off onto food and get into your mouth where it might be harmful.

You have a couple of interesting points here.

(1) Do soaps actually remove heavy metals?  I guess if they are embedded in the oily layer of your skin they should, but what if you wash your hands, return to work and wash your hands again?

(2) Even though the lead does not wash off does not mean it will not end up being consumed.  If has to go somewhere and leave the hands somehow, otherwise you would eventually end up with solid metal hands.  Although you suggest the amount of lead that may enter your food may be low, do we know how this looks over a long time period? 

[Whales]

Thanks for the links Catalina.

https://www.cdc.gov/niosh/hhe/reports/pdfs/2007-0201-3086.pdf

You can compare it to your own soldering to see if you are concerned, but the CDC did not find anything particularly worrisome in the evaluation.   It is worthy of note that they found lead on the workers hands even after hand washing.  But it is also worth thinking about how lead that can't be removed by handwashing will somehow wipe off onto food and get into your mouth where it might be harmful.

From the above:

We collected hand wipe samples for lead from 23 MS and 37
DAS employees at lunch and asked whether they had washed
their hands just prior to providing the wipe sample. Seven of
the 60 wipe samples (3 from MS, 4 from DAS) showed a color
change indicating the presence of lead. Three of the four wipe
samples collected from DAS that tested positive for lead were from
employees who had washed their hands prior to sample collection.

This is pretty crappy on the tester's part.  If I had been handling this stuff for years without washing my hands, I probably wouldn't tell them the truth.  Also hand-washing can be anything: a quick one-hand rinse to a five-minute long scrub.   How is everyone even washing their hands?  What are the concentrations needed to change the colour of the test samples?  I wonder how the wipes collected lead if the hand-washing was ineffective.

(Some of these questions may have been answered, I'm only skim reading through the doc ATM.  Apologies if I miss something)

There is also the possibility the lead came from after they washed their hands:

[...] We also sampled a larger surface area
inch by 12 inch) of the break room tables to ensure that they
were clean and found detectable levels of lead and tin in one of the
break rooms.  [...] 

[coppice]

This is pretty crappy on the tester's part.  If I had been handling this stuff for years without washing my hands, I probably wouldn't tell them the truth.  Also hand-washing can be anything: a quick one-hand rinse to a five-minute long scrub.   How is everyone even washing their hands?  What are the concentrations needed to change the colour of the test samples?  I wonder how the wipes collected lead if the hand-washing was ineffective.

Copper on the skin makes your skin feel strange, so you know its there. It takes some vigorous washing to eliminate that feeling. I expect most metals are just as hard to thoroughly remove from your skin, but you need lab tests to detect if most of them are present. People who work with radioactive materials carry tags which monitor their exposure. There is nothing similar for people working with a wide variety of toxic materials that are hard to detect visually.

[Brumby]

Contact with lead doesn't influence my hand washing.  Handling anything grungy does.

[Cerebus]

The article suggests that solder will poison you if you do something really stupid - eating large amounts of solder.  This is consistent with the reports of waterfowl being poisoned by eating lead shot, and also consistent with the reports here of biting (but not swallowing) lead sinkers without bad outcomes.

We should be careful of comparisons between species. For a start, toxicity mechanisms may be very different at the biochemical level. Secondly, waterfowl are a particularly dangerous comparison. The physical lead shot may be in the system of waterfowl for much longer as they almost certainly deliberately ate them along with small stones to store in their gizzards where they would be used as, effectively, an abrasive to help break food down. The abrasive action would release more lead and the shot would be present over a longer period than that just passing through the digestive system of a mammal.

[helius]

The lead shot eaten by wildlife are also frequently laying in a wet brackish environment that oxidizes the lead, making it more bioavailable.

Personally lead is way down my list of toxicity concerns in dealing with electronics, after things like cadmium plating, beryllium dust, glass fibers, and contact cleaners. Rather hazardous electronic cleaners like hexane, trichloroethylene, and bromopropane are still sold for the industry.