# Where to solder, concerns about fumes

#### -live wire-

Joined Dec 22, 2017
912
I'll probably get this fume extractor, as a reasonable precaution. Or maybe I'll spend a little more and get one like this. My main concern with lead is that it is a hazard to have around. I don't just want to reduce my exposure slightly. I also want to eliminate the possibility of a pet or family member getting significant exposure to lead.

#### OBW0549

Joined Mar 2, 2015
3,566
This one would be even better, as it could double as a work table. Plus, with the steel grate top, there's no danger of you getting sucked into the air intake.

#### dl324

Joined Mar 30, 2015
12,678

#### -live wire-

Joined Dec 22, 2017
912
I read that article and one thing that infuriated me was the "it's okay because it's natural" argument. You don't go into the woods and eat random mushrooms you find. Nor do you sell them and say "well, they're natural, so don't worry". Regardless of the source, it has certain chemicals in it, which still have the same effect.

#### Raymond Genovese

Joined Mar 5, 2016
1,658
This thread reminded me of something I read about red LEDs having more lead than other colors. This amused me because lead isn't used in the manufacturing of red LEDs.

https://newatlas.com/led-bulbs-found-to-contain-toxic-metals/17876/

View attachment 154252

I suspect their technique was flawed and the lead came from solder used for assembly.
At first I was not going to respond to this as it is a bit off-topic, and then I thought that it is, in a way, very much on topic. It illustrates well, the difficulty of getting good data and the extant misrepresentation that takes place which serves to cloud the data (and give rise to charges of overreaction and so on) that is very much part of the topic.

I remembered something about this from several years ago, so I spent the last hour or two trying to find the study to see for myself. What I easily found was an apparent press release from the University (NOT from the authors of the study) https://www.ledsmagazine.com/ugc/20...riendly-contain-toxic-metals-study-finds.html and MANY "soft" news-type blurbs and several "rebuttals", such as this one https://www.ledsmagazine.com/articles/2011/02/study-looks-at-toxic-metal-content-of-leds.html (which is particularly reasonable).

So, here's my point, the "press release" and many of the news reports (look for yourself) are misleading. To be more accurate, in my opinion, the press release is misleading and the news reports based on the press report were, as you might guess, even more misleading and were poorly summarized for impact (I doubt some of the writers of those news reports ever read the actual study, but I am speculating). Some were clearly defensive (e.g., http://www.remphos.com/images/RemPhos-letter-on LED-Environmental-Impact-150622.pdf).

At this point, I was still looking for the actual &*#@ published study! (see this thread https://forum.allaboutcircuits.com/...s-without-going-bankrupt.148575/#post-1268133). Persistent to a fault, I finally found it here

[click on PDF on the right side]

I am not a materials scientist, but I don't see anything wrong their methodology or design. I see their results as very limited and literally begging for follow up. They used Red, Yellow, Green, Blue and White. There were high and low intensity varieties for each, except White.The study was funded by NSF.

Read it for yourself and correct me if I am wrong. Basically, they ordered 9 (N I N E) LEDs from a local CA manufacturer (their name is given and I looked at the site and I think that they are manufacturers). Then they analyzed the LEDs, fresh out of the box. The analysis methodologies that they used appear to be well-justified and somewhat standard for this kind of work.

They found, in a SINGLE Red LED, Pb that was (~8 times I think) higher than the legal state standard. There was either no detectable lead in any other LEDs or the amount was 1000 times less than that one LED.

There were issues with Copper, nickel and silver in various LEDs (see the table).

Now, on the one hand, what they found is what they found and it is not trivial. To be clear, however, I would want to know how representative the data are as because that is a huge factor in determining the significance and impact of the results.

As a scientist, I want to know what the heck was different about that LED?!

I know very well that first you have to accurately report what is, and then you get to start trying to learn why it is. I give credit to the scientists, they reported what they found, how they found it and they interpreted their results with regard to environmental/regulatory context. If I had reviewed the manuscript, my first request would have been for the authors to address the limited generality of their findings (it is there, but somewhat couched in the usual 'more studies are needed...').

There are two points that I find unacceptable and sad.
1) I can't easily find the answer to my question - is this typical with LEDs - what are the means and SDs from followup studies using a larger n and from multiple sources. Why can't I get that front and center in 2018 when the study came out in 2011? Do I just not know where to look?

2) Media coverage of science and technology frequently, but no always, sucks.

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#### -live wire-

Joined Dec 22, 2017
912
Sounds like fake news!
I would be highly skeptical of a purely observational study but they additionally did testing. It seems to actually be more legitimate. Obviously citing sources would be far better but it seemed not completely terrible.

Regarding red LEDs, I heard that they commonly use non-RoHS materials to make them red. But then I assume they would be marked as non-RoHS. And I have over 20 red LEDs lying next to this computer, stuck to a magnet, as I write this.

Joined Jul 18, 2013
22,642
My main concern with lead is that it is a hazard to have around. I don't just want to reduce my exposure slightly..
I grew up when lead was used in everyday paint, lead pipes, all sorts of applications.
White lead was also favorite in machining etc.'
In the 80's I helped maintain a Railroad manufacturing facility where white lead was used to press on car wheels on to the car axles.
Long time operators of the press-on machine appeared to succumb to some kind of cancer before, or just after retirement in disproportionate numbers?
Max.

#### MisterBill2

Joined Jan 23, 2018
8,215
This thread reminded me of something I read about red LEDs having more lead than other colors. This amused me because lead isn't used in the manufacturing of red LEDs.

https://newatlas.com/led-bulbs-found-to-contain-toxic-metals/17876/

View attachment 154252

I suspect their technique was flawed and the lead came from solder used for assembly.
Just as a precaution, I very strongly suggest that everybody refrain from eating red LEDs! Eating them may lead to serious health problems. I read it on the internet and so it must be true!!!

#### joeyd999

Joined Jun 6, 2011
4,477
Just as a precaution, I very strongly suggest that everybody refrain from eating red LEDs!
Maybe they're made with red dye #2?

#### Sinus23

Joined Sep 7, 2013
246
We are going to need a real cancer scientist, not just a doctor but a scientist up in here. All seriousness aside. I pretty much do what many members have suggested before they even suggested it because it comes natural as basic precautions like breathing in before you solder a joint, blow the fumes away when you're done and have some air circulation like open a window.

I'm somewhat sure that I breath worse things while walking to the store or a bus stop in a city that has more than 20K vehicles going from a to z every day. Oh and the whole industry complex output in close range.

#### MrChips

Joined Oct 2, 2009
23,077
Without attempting to diminish the concern that the TS has for safety, I believe that one has to put the risk factor into perspective. There are risks in everything we do. There is a risk to health and life just climbing out of bed.

The risk to health and life just crossing the street is greater than that of occasional soldering.
Do you drink bottled water from plastic bottles? There is research that links male infertility to the presence of plastics in our environment.

Would you dare stick your head in a microwave oven (even if you were allowed to defeat the door interlock)? Of course not.

We want to minimize all risk where we possibly can and have some control.
So for starters, stop drinking bottled water.

And while I'm at it, there is demonstrable fact that the use of smart phones is dangerous to your health (and even non-users) because of its addictiveness, behaviour modification abilities, and tendency to cause distraction.

#### shortbus

Joined Sep 30, 2009
8,432
Without attempting to diminish the concern that the TS has for safety, I believe that one has to put the risk factor into perspective.
Just an observation. It seems from past posting of the thread starter, that the risk seems to be piing off his mom/wife, if he doesn't do something.

#### dl324

Joined Mar 30, 2015
12,678
Regarding red LEDs, I heard that they commonly use non-RoHS materials to make them red. But then I assume they would be marked as non-RoHS.
The problem here is that you can't make general statements about how LEDs are attached to the lead frame (no lead is used in the manufacture of the LED die), and how the leads are treated. You can't tell the difference between a RoHS and non-RoHS LED by looking at an assembled LED.

Back in the 70's, HP used conductive epoxy to attach the LED cathode to the lead frame. Leads were sometimes silver plated or tinned with solder. Some manufacturers solder the die to the lead frame.

The problem with the UC study is that they didn't give manufacturers or part numbers, so they're making some incorrect assumptions. That makes their study flawed.

#### Raymond Genovese

Joined Mar 5, 2016
1,658
The problem with the UC study is that they didn't give manufacturers or part numbers, so they're making some incorrect assumptions. That makes their study flawed.
No.

The manufacturer and part numbers (as well as additional details) that they used appeared in the supplementary information as per the text in the article (typical publisher decision to reduce pages).

You can see this for yourself here: https://pubs.acs.org/doi/suppl/10.1021/es101052q/suppl_file/es101052q_si_001.pdf Table S-1

#### jaredwolff

Joined Jul 1, 2017
58
While other folks here don't have a problem with it, I definitely do not do any soldering and flux work without nitrile gloves and fume extractor. In some cases the flux is the nastier of the two. Most factories that I've worked with and visited have some type of fume extractor for their workers. I don't go a day of soldering without using mine. Here's link to it.

Paranoia? Maybe. I only have one set of lungs and I intend on keeping them until the day I don't.

#### -live wire-

Joined Dec 22, 2017
912
While other folks here don't have a problem with it, I definitely do not do any soldering and flux work without nitrile gloves and fume extractor. In some cases the flux is the nastier of the two. Most factories that I've worked with and visited have some type of fume extractor for their workers. I don't go a day of soldering without using mine. Here's link to it.

Paranoia? Maybe. I only have one set of lungs and I intend on keeping them until the day I don't.
Why would you use nitrile gloves?

#### MrChips

Joined Oct 2, 2009
23,077
Why would you use nitrile gloves?
It is like using a prophylactic, if you want to be safe while doing whatever you are doing.

#### MrChips

Joined Oct 2, 2009
23,077
Better to be safe than sorry.