The Case for Lead-based Solder

[Alarm Siren]

The primary purpose and concern of RoHS is in where those restricted substances would end up after the end of the useful life of the product. The concern is not about the health of the manufacturing staff (though not using the materials covered certainly can't hurt in that regard), or the health of the user of the product (they really shouldn't be eating it anyway!).

Fundamentally, RoHS substances could be safely used in products if we, as a species, bothered to dispose of our waste properly, but we don't. Take for example Cadmium (which is also covered by RoHS). Wonderful material for making weather proof connectors and widgets, and you can also make Cadmium based paints for your ships which protect it from weathering. The flip side is that it is a carcinogen that persists in the environment for a long time.

Now in use, that Cadmium is contained and fairly inert, but when you decommission your ship where does the Cadmium go? If we disposed of it properly, it'd be fine, but instead we sell it to a wrecker who sails it to Panama (who pinky-promises to deal with the cadmium properly), strips out all the good bits, sells the husk to India who strips out the mediocre bits, then sells the remains to a Bangladeshi company who finally strips out all the uncontaminated steel and leaves the cadmium painted bits to weather away in a river basin, polluting the environment, not to mention the drinking water of thousands.

Exceptions exist to RoHS for high-reliability space, medical and military applications precisely because it is understood that the replacement materials are functionally not as good and, where long-term reliability is paramount, some sacrifices can be made on the understanding that (in theory) those materials should be properly controlled and disposed of given the nature of the application.

The medical exception, for example, only applies to equipment that will be placed inside the patient's body - such as a pacemaker. It is entirely reasonable that a pacemaker, which has to work for a decade without maintenance and the consequences for failure is the death of the patient, must use the best solder. Equally when the pacemaker is eventually replaced, it will be properly disposed of, because its both biological waste as well as e-waste at that point and there are specialised processes for dealing with that.

Frankly, given that, as a species, we haven't figured out how to not destroy our own planet, I think its entirely reasonable that I/we sacrifice a little reliability in our consumer electronics (which very rarely fail because of solder issues anyway - typically they "fail" because of planned obsolescence more than anything else) for the sake of others, for the sake of the environment, and for the sake of future generations.

What is more important - the slight inconvenience that your DVD player (might) break, or that we not fill our environment with harmful chemicals? I know which way my vote falls.

[sburrow]

Alarm Siren wrote:

The primary purpose and concern of RoHS is in where those restricted substances would end up after the end of the useful life of the product. The concern is not about the health of the manufacturing staff (though not using the materials covered certainly can't hurt in that regard), or the health of the user of the product (they really shouldn't be eating it anyway!).

Wow, that was the best explanation I've gotten yet on the topic. VERY well spoken, thank you for that. I might have my own opinions about this or that, but overall that is convincing.

But as you mentioned, there are exceptions. And where there are exceptions, there is subjectivity. And where there is subjectivity, there are humans taking advantage of this or that for their own profit and gain. And who is going to regulate these regulations? What is *their* gain?

In the end, I won't be changing from my lead-based solder because of this, because I'm just one guy playing with 80's level technology. I'm not big enough to care about. But at least I won't look down on the RoHS compliant stuff (as much) anymore. Thank you for the detailed analysis!

Chad

[Alarm Siren]

sburrow wrote:

And where there are exceptions, there is subjectivity. And where there is subjectivity, there are humans taking advantage of this or that for their own profit and gain. And who is going to regulate these regulations? What is *their* gain?

Absolutely agree, but that some people are inconsiderate or selfish is not, in my view, a valid argument to not do the right thing oneself (or in this case, to put up with the slightly inconvenient mandate). Making the situation 80% better is still 80% better than it was before.

sburrow wrote:

because I'm just one guy playing with 80's level technology. I'm not big enough to care about.

In the EU and UK, RoHS does not apply to anything you build yourself, nor to prototypes. The duty of RoHS applies to companies selling end products to the consumer. It is perfectly legal to purchase and use leaded solder for your own use, and indeed I have a roll of it at home (I live in the UK). I also have a couple rolls of non-leaded.

sburrow wrote:

But at least I won't look down on the RoHS compliant stuff (as much) anymore.

I'm glad you found my post helpful
It's something I have to be very aware of because of my work...

[Alarm Siren]

Also to address Lead more specifically, people talking in earlier posts about lead pipes and other lead-based products.

The problem with leaded solder only really becomes an issue when you improperly dispose of it (see above); but for things like lead pipes, lead-based cosmetics, and tetraethyl lead-based petrol additives, the danger is not lead but lead oxide.

Whilst lead isn't great for you at the best of times, as BDD rightly pointed out your body has a certain level of natural tolerance, and its fairly inert in its metallic form so not much is absorbed by your body anyway - unless your exposing yourself to lots of it over a prolonged period. But lead oxide is much more readily taken up by your body because it can dissolve in water and is thus, gram-for-gram, many orders of magnitude worse.

lead-based cosmetics don't contain lead, they contain lead-oxide because it is white and they use it as a white pigment. lead pipes contain lead oxide wherever there are little pockets of air (as it forms in the moisture-rich pockets), then dissolves into the flowing water and ends up in your body. Tetraethyl lead, when burnt in an internal combustion engine with fuel, generates a whole cocktail of nasty chemicals, part of which is - you guessed it - lead oxide.


As a final point:
Just because as an individual one has not experienced or seen any negative effects from something, doesn't mean those effects are not real. There are smokers who smoke a pack a day from age 12 to age 102, but those people survive that long because they were lucky, not because smoking is not dangerous. Lead may not yet have seeped out of your local rubbish tip into the ground water - and it may never do so - but that doesn't mean it doesn't happen. Individual experiences are always binary - either you experienced it, or you didn't - which is why we use statistics and research to show how the bell-curve of risks change across the population for given variables.

[BigEd]

All very nicely said, thanks Alarm Siren!

[Dog Cow]

BigDumbDinosaur wrote:

Lead occurs naturally in ground water and all living things have been ingesting water with trace amounts of lead in it for millennia. At the risk of being Captain Obvious, it’s likely evolution has caused organisms to adapt to and tolerate lead content as a matter of survival.

There's also trace amounts of asbestos in the air all around us. In this case, asbestos is just a mineral fiber that floats around.

GARTHWILSON wrote:

Without lead, solder tends to crack more easily. Consumer PC accessory boards I've gotten that were RoHS quickly got cracks in the solder connections that had to handle some stress, like an SD-card socket. Re-soldering with leaded solder fixed them, and kept them working.

Lead is extremely ductile. It's like a tree blowing in the wind: it flexes. This is why plumbers caulked cast iron pipe joints with lead: everything in a building moves at least a little bit (from foundation settlement, temperature change, and so on), and the lead in the joint is ductile and moves along with it, instead of cracking.

GARTHWILSON wrote:

I spent years in a boarding school in another country where our water came to us in lead pipes. A high percentage of those kids went on to become doctors and engineers; so I'd say the lead didn't have any negative impact on our brains.

The solution to this concern of lead supply pipes (which was a concern even 100 years ago) was to run the water for a minute or so every morning. It's only a problem when water stands in the lead pipe for hours or days at a time. Also the inside of the lead pipe develops a film or coating from the contents of the water. Once someone has flushed the stale water of out the supply pipes, the risk is greatly reduced.

sburrow wrote:

2) Lead is heavier than air, so lead isn't present in the fumes.

I would double-check the accuracy of this statement if I were you.

barrym95838 wrote:

I think the point the "zealots" may be trying to make is that smoking bans and other things like motorcycle helmet laws are designed to reduce the burden on the health care and insurance systems, to the benefit of all.

These bans on vices, including smoking, are also in a large part motivated by the dependents whose livelihoods are adversely affected, and these dependents have no choice in the matter. In your example, it's second-hand smoke.

AndersNielsen wrote:

sburrow wrote:

1) Folks back in the day lived quite longer than a lot of folks do today, but we are *told* that most people died early by "the experts". We do have antibiotics and other things keeping us alive longer than expected, and honestly just better hygiene in general (i.e. we use soap/disinfectants before surgery). But people back in the day were eating real foods and herbs, and didn't have pharma drugs. The human body is amazingly adaptive to the surrounding environment.

"Folks" most certainly did not "live quite longer than they do today". Malnutrition was one of the biggest parts of that statistic.

Death by fire (not necessarily an entire building ablaze, but also from kitchen fires) and death by suicide (self-administered poison and gunshots being typical agents) were more common in the past.

People also died from causes that have largely been eliminated in today's environment: it was more common to be killed or injured by livestock such as horses, mules, and cows. Remember that cities too were full of livestock 110+ years ago. Also, with gas lighting, people who had little experience with gas light (maybe they lived in the country, or in a small city without a gasworks) and who stayed in a hotel with gas light would make the mistake of blowing out the flame as if it were just like a candle. But they did not know to turn off the gas key, so they would go to sleep and be asphyxiated by the gas in their closed room.

[No True Scotsman]

sburrow wrote:

So many folks say the decline of the Roman Empire was due to lead pipes.

It wasn't just water pipes. The Romans cooked food in lead pots. Roman women wore makeup containing lead. It's a safe bet they were exposed to more lead than we were growing up in the 70s.

[barnacle]

Though I believe it turns out that floating in warm water somehow leaches heavy metals from people. And the Romans were awfully fond of baths, either natural hot springs or heated by fire.

Well, at least the ones who could afford the luxury.

[BigEd]

It looks like the question of the importance of lead poisoning to the Romans reappears every twenty years or so in the literature - I suppose that's the cycle of academic careers. It doesn't appear to be well-settled, which is a pity. Probably in academia it's too much of a reductive kind of idea to get serious attention, whereas in the media and popular culture it has the attraction of simplicity.

[barnacle]

There is apparently an interesting delayed link between societal violence in young people and the presence and absence of tetrethyl lead in petrol...

Neil

[ebadger]

This seems relevant to the topic:

[BigDumbDinosaur]

ebadger wrote:

This seems relevant to the topic...

As long as he didn’t chew and swallow the solder, it would have been unlikely to have any deleterious effects on him.  That said, I would never use my mouth to hold and guide the solder.

[Dr Jefyll]

Most of us have occasionally found we don't have enough hands to complete some soldering.

In another thread, I described a solution I've sometimes found useful:

Quote:

Take the spool of solder and unwind about 10 inches. Place the spool on the edge of the workbench, with the loose end extending outward and drooping down. Then, to do the actual solder joint, hold the circuit board on your knees so you can move it around horizontally; and also up and down somewhat by stretching your toes. In other words, move the connection to where the solder is, rather than vice versa. In effect, your knees function as an extra hand.

BillG remarked that that sounded uncomfortable, but...

Quote:

I start by pulling the chair a little further away from the workbench. But my posture is hardly any different than usual. Really the only difference is arching my heels off the floor slightly when it's time to actually solder. The amount of motion is less than an inch. Same for the X-Y motion -- you only need enough to fine tune your aim at the bulls-eye. Everything is 99% in place before you begin.

-- Jeff

[sburrow]

I sometimes use 'tubes' of lead solder and stick the tube in my mouth.

https://www.mouser.com/ProductDetail/Ch ... 8BhQ%3D%3D

I haven't done that in a while though, I normally find other ways now-a-days. What I need to get is some sticky-tack or play-dough, I've seen some folks use those on repair videos to hold things in just the right spot.

Chad

[anomie]

Reading this thread through I find myself thinking a lot about survivorship bias.

Not that I know or can claim much about the actual effects and what levels are needed, etc - just that any people who actually did experience significant cognitive decline, or other deleterious effect, due to lead exposure would pretty probably not be here to counteract the “we did this and we’re all fine” side of it.

That said, I do have leaded solder, but I take what I consider to be appropriate precautions, disposal, etc.