How concerned should I be about Lead (Pb) content of free machining metals?

[JAndrew]

HMEM,

I've been doing more projects with 12L14 steel and looking at future projects with brass alloys. 12L14 and most machinable brasses have a Lead (Pb) content of a couple percent. How fearful should I be of this Lead.

Maybe I'm just oversensitive to this topic because I live in California "The Land of Infinite Cancer Warning Labels" but I feel more concerned about it since I have a young child in the house. Lead can be bad stuff for small children.

The other day I was sanding some 12L14 with emory cloth and the shiny dust was all over me afterwords. I wear a dedicated shop apron and take off my dedicated shop shoes before going into the house (and sometimes my other clothes too). It brings to mind so many other questions though...

Should I be wearing a dust mask for that type of sanding? Should I wash these clothes separate from other laundry?

When I think about it I want to say, "Nah the lead is trapped in a steel or brass matrix..." but I don't really know how serious the risk is...?

Are leaded brass alloys skin safe for jewelry type items? etc...?

Any insight from the safety keen would be greatly appreciated.

-JAndrew

 

[goldstar31]

I think that you are possibly being over influenced by what you read and consequently are being brain washed. Of course it is true that ingesting lead will probably be harmful, there are lots of other things which will be a lot worse for you and your family.

I'm 83 and a big bit and have had all sorts of 'influences' in those years. I had a lot of lead, some of it came out of the ends of guns but a great deal more came out of leaded petrol/gasoline. On the latter, there is far more danger coming from carbon emissions from exhaust fumes from fuels that have no lead.

I'm sitting here as a bit of an old dodderer- but I am sitting here. Others are not around anymore. There are three 'Goldstars' left from my generation. I've just had a letter from one who is recovering from a heart attack. Eddie was one of my assistants, he never smoked, never drank alcohol, was half starved rather than being overweight. I got him another shilling a day because he was a vegetarian and wouldn't eat the poor food that we had to eat. But my poor lad is a lot worse than me. The other Goldstar had his ears blown out- working on Spitfires and ingested 100 octane fuel that Merlins took. He washed the oil out of his overalls in aviation fuel- and put them on again. He technically died sometime ago- on the slab- has had new hips and knees being overweight and so on. He's still around, still chasing the opposite sex at 84 and has had a prostatectomy. Go figure!

Me, I still can get into my old suits, I've played about with lead, paints, weights, car body metals, smoked, drunk like a fish- and eaten all the wrong foods.

On a even more serious note, my son in law is a senior consultant heart surgeon who is skinny like me but I seriously doubt that he will make 55 years.

There is something called 'The Genes', it is still unexplored territory or territory which needs a lot of further research.

If you have these genes, you have them. If you haven't- tough.

I hope that you are like me- Lucky.

Norman

 

[JAndrew]

Goldstar31,

Thanks for the reply. You're probably right about "being over-influenced." That was no joke above about cancer warning labels. California puts these Prop. 65 warnings on anything even remotely toxic telling you in so many words "YOU WILL GET CANCER AND DIE FROM THIS!"

True story, where I work we got a shipment of new coffee cups with the plant logo printed on the side. On the bottom of each cup was a Prop 65 Cancer warning! I guess the paint used for the logo had something remotely hazardous in it so they all had to be labeled by CA law! The management hummed and hawed about whether to even hand the mugs out. When they finally did very few people took them!

As to the lifespans, I agree that "genes" play a big role but I also think the temperment of the person has a big effect. I bet your son-in-law, being a heart surgeon is stressed out all the time. That won't help.

When my mother struggled and finally passed of cancer I believe it most mostly due to her lack of desire to live. Being a manic depressant or a nervous nelly can't be good for your body.

Thanks for the repl. We'll see if anyone else has any insight.

-J.Andrew

 

[barnesrickw]

Lead poisoning is more of an issue for children under the age of three. It causes drain bamage. Not to say I would breathe copious amounts of fumes and dust 8hrs a day for many years. I think someone brought up the point of lead propelled by gunpowder is the most dangerous. The exposure limit is about 50micrograms per cubic meter of air for eight hours a day. So if your shop has no airflow and is very small I would wear a mask and change my shop clothes before I play with my children. Here is what OSHA has to say about it. https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=standards&p_id=10030

 

[barnesrickw]

12l14 steel contains at most 0.35% lead by weight. Let's assume your shop is 20 m^3, you would have to machine about 13 pounds per hour for 8 hours a day of 12l14 per day, converting it all to dust you breathe to reach the 5 micrograms per cubic meter for 8 hours a day to reach the exposure limit for lead. I think. (0.000005g/m^3)*20m^3 or .0001g for your shop. 1pound equals 454 grams (don't ask how I know that one) divided by .0035 for the % lead in 12l14 = the amount of that steel you have to mill to reach the exposure limit.

 

[Tin Falcon]

J

I think there is no need to worry.
If you have not done so read the shop safety sticky thread in the safety sub fora.
The main thing I will say. is use basic industrial hygiene practice in your home shop.
Clean off the machine after using.
Wash your hands before eating smoking or using the bathroom.
Have good ventilation .
Probably not a good idea to wear the same clothes in the shop that you sleep in.
If you have a young child or grandchild you may want to wear an apron or smock/labcoat to keep possible contamination off the clothes you are wearing while young kids are on your lap.

If you are sanding or grinding any metal without flood coolant. Like most of us do from time to time a little more caution may be in order like wear a dust mask and put the work clothes in the washing machine at the end of the day.


The one metal I will not bring in my shop is berilium copper. That stuff has a bad rep.

IMHO having a using lead in the shop in pure or alloy form is useful and not a big deal .
If when I need to melt it I work out side . And I do my welding and most grinding outside as well just better ventilation and less chance of contaminating the shop and my home.


As far as working with lead I did a lot of lead casting as a teen both inside with a range hood over the work area and outside.
I have a healthy intelligent son and just recently a healthy grandson.

Tin

 

[Gordon]

J


Probably not a good idea to wear the same clothes in the shop that you sleep in.

Tin

Does that mean that I cannot take a nap in the afternoon in my shop? If I go into the house for a nap my wife will find other things for me to do.

 

[Tin Falcon]

Does that mean that I cannot take a nap in the afternoon in my shop? If I go into the house for a nap my wife will find other things for me to do

LOL
Did not think of that one.
Interesting Point . Well your shop your rules. My point is do not wear your pJs in the shop then crawl into your bed in the bedroom. Honey!!!!! there's is swarf in the bed again!!!!
I think you get the point here follow hygiene rules that keeps the shop dirt out of your personal life . Do not cross contaminate the wife, kids, grand kids, dog or cats with harmful chemicals or metal dust.
Tin

 

[goldstar31]

I think that we have drifted a little from the Pb( lead) dangers but the overall point is health( I think)
So what about mercury? We've all read about the Mad Hatter, the story written for a little girl who tried to become the Queen of England. Perhaps you missed the real story of Alice Pleasance Liddell, but she did. However, the story points to somewhere to mercury poisoning as well. Oddly, many of us have mercury in our dental fillings or at least, use oldies have. Are we concerned or simply, have we forgotten? One thing seems certain, my better half( her view) is that she played with mercury from broken thermometers along the top of her school desk. Believe me, I also enjoyed it. But my better half( ?) spent her life playing with more and more of the stuff -mixing dental amalgam- with her fingers. Is she merely a one off- an exception to the rule? Well, she has already celebrated 50 years since she qualified as a dental surgeon- so she started 4 years before that. But, and it is a big but, she joined her year at a banquet in Newcastle upon Tyne and half the 'intake' or was it 'Inn-take' were alive and kicking at the 'bun fight' despite doing the same risky procedures. One, oddly had time to edit two books on model engineering.

One wonders about statisticians, perhaps they should meet real people.

Me, I'm sticking with Genes concept.

Keep well, mind the buses and keep away from wars

Norman

 

[Tin Falcon]

FYI i just posted a thread discussing shop ventilation and dust collection.
http://www.homemodelenginemachinist.com/f19/ventalation-22595/#post241599
Tin

 

[Till]

12l14 steel contains at most 0.35% lead by weight. Let's assume your shop is 20 m^3, you would have to machine about 13 pounds per hour for 8 hours a day of 12l14 per day, converting it all to dust you breathe to reach the 5 micrograms per cubic meter for 8 hours a day to reach the exposure limit for lead. I think. (0.000005g/m^3)*20m^3 or .0001g for your shop. 1pound equals 454 grams (don't ask how I know that one) divided by .0035 for the % lead in 12l14 = the amount of that steel you have to mill to reach the exposure limit.

Unfortunately this is not the case. There is no direct relationship between lead concentration in the air and lead concentration in the blood.
This is mainly because of the protective filtering characteristics of the lungs (ingestion is much less dangerous).
Bigger particles stick to the mucus in the lungs, get transported outside and won't do much harm. Very small particles matter, as they end up in the alveoles where the lead enters the blood. (Dust, vapors)
Separation of big particles looks good in terms of weight, but allows the dangerous "nanoparticles" to pass so the impact on health remains the same... It's comparable to diesel particle filters.

 

[goldstar31]

We Brits get our education( such as it is) from watching a rather amusing TV program called QI-( Quite Interesting)

One of the snippets was about- lead poisoning and obviously came to discuss the ill fated Sir John Franklin Expedition to find the North West Passage in Canada. Lead poisoning was suspected as being the culprit and which came from lead solder used to can food. It wasn't really the cause of the deaths because that came from- eating each other.

 

[barnesrickw]

Somebody else sets the limit. I just did the math assuming all the lead in the material machined became dust that added to the limit. I guess my point was I don't think most hobbyist are going to be milling 13 pounds of 12l14 all day.

 

[JAndrew]

All,

Thanks for the replies. Seems like the consensus is that what I'm doing is probably good enough or even overkill. I will be making one change though...Anytime I sand any leaded metals from here on out I'll probably hit them with a little WD-40 just to keep the airborne dust down.

I didn't realize that 12L14 has less than 1% lead content. I thought it was more. Even California says brass alloys with less than 1% lead are safe for use so I guess I need not sweat it.

Anyone know the answer to my one remaining question about leaded brass not being used in jewelry due to skin contact? I read that somewhere but can't seem to find any affordable brass stock that has no lead content. I ask because I'd like to make a couple slide whistles for the kiddo's and was planning on using brass tube before I read that.

Thanks again all.

-J.Andrew

 

[Nerdz]

If I recall correctly, some door knobs are made out of brass because they are anti-microbial. Copper has the property of "killing" bacteria, as does stainless steel (takes a bit longer though). A quick search on google using the terms "Brass door knobs kill germs" brings up a ton of results. The only reaction your children might have is if they are allergic, plus as far as brass goes I think they would have to ingest the powder. As I was told when I was buying a house (in reguards to old windows); the only way you can get lead poisoning is if you chew on the window sills (I live in a area where old houses are common)

Actually, now that I think of it, the website where I get jewelry supplies from, Sells brass for Jewelry!

 

[barnesrickw]

Brass tarnishing is probably the big jewelry issue. It's probably the copper in the brass that kills the bacteria.

 

[Wizard69]

Lead in steel isn't likely a problem for you? It is however a problem for small children if they get ahold of it an ingest it.

However lets be realistic here, when it comes to safety there is no place in a workshop for a small child, especially one not closely supervised. In the average shop there are massively more dangerous things than lead as far as the safety of a small child goes. Let's be honest a child can die or be partially dismembered in a shop quicker than you want to imagine. The ugly truth is children just can't grasp the dangers of mechanical things. Or electrical, chemical or other dangers. Think about what would happen if a child got into a paint / solvent cabinet for example.

So in a nut shell if there. Is a small child in the house YES you need to be concerned about safety. However lead would seem to be a minor issue in comparison to the more immediate problems. In a nut shell keep the kids out of the shop until they can grasp the safety issues or be prepared to dedicate your attention to supervising them.

 

[Nick Hulme]

Lead in steel isn't likely a problem for you? It is however a problem for small children if they get ahold of it an ingest it.

Credible scenario for the ingestion of enough material to prove a hazard?