Toxic Leather Wrist Watch Bands

[boblalux]

As, like many people, I prefer wristwatch bands made from leather, I usually swop often sharp-edged metal bands, and co**BLEEP** rubber diver's bands for leather. Until recently ! When one reads about the production of leather using Chromium-6 salts for tanning which are carcinogenic, and I know not what other horrible chemicals, one shudders. I recently bought a number of leather bands on Ebay from China, which I found to smell very suspect and 'unleatherly'. The old system of using urine for tanning is relatively harmless ! Although chromium-6-treated bands don't smell, I am considering reverting to steel or rubber bands. Any comments ?

Edited April 6, 2015 by boblalux

[ro63rto]

Chromium-6 is also found in tap water.....

[Geo]

I personally won't lose any sleep about wearing a leather strap, just as I won't lose sleep about wearing watches with old radium lume. If I was involved in a trade where I was grinding leather, as in sho repairs, or scraping off old lume from watch hands, I would certainly take precautions to prevent inhalation of any dust produced.

Have you ever heard, or read about someone developing cancer from wearing a watch strap? Serous question by the way.

[boblalux]

True, I know this as a pensioned chemist.  But if the total chromium in your tap water is >0.1m/l  (EPA limit), then you had better buy bottled water to drink!

Leather treated with chromium on your watch band + your sweat, will deliver much higher values.

Bob

 

PS Have you ever heard about someone developing cancer from smoking?

Edited April 6, 2015 by boblalux

[WillFly]

I think if I was worried about wearing watch straps made from leather tanned in China, I'd simply stop buying straps made in China. As it happens, I've bought the odd cheap strap from China - but only to fit on to a a fairly average s/h watch in my collection as part of a refurbishment - not to wear regularly, if at all. I can't recall any peculiar smell from them at the time of purchase - though I'd be interested to know the actual composition of the tanning agent used in China, and whether there are any regulations coming into force through health and safety. I am aware that the toxic method tanning in China and India is an environmental disaster and a serious health hazard to the workers.

 

For wearing watches, I buy good quality straps made in Europe - but, to be honest, I couldn't tell you whether these straps are from leather tanned in the traditional way or by more modern methods. I assume that more serious controls are in force in the West and, from what I've read, tanneries are far more tightly controlled.

 

With respect, I would add that the analogy with lung cancer and smoking is perhaps not quite in the same league as cancer and wearing a watch strap...

[Geo]

PS Have you ever heard about someone developing cancer from smoking?

I sure have, my grandfather died of it at the age of seventy two, my mother on the other hand smoked like a chimney from the age of fourteen and died of heart failure at ninety! I am not a smoker by the way and detest the habit.

[boblalux]

I think if I was worried about wearing watch straps made from leather tanned in China, I'd simply stop buying straps made in China. As it happens, I've bought the odd cheap strap from China - but only to fit on to a a fairly average s/h watch in my collection as part of a refurbishment - not to wear regularly, if at all. I can't recall any peculiar smell from them at the time of purchase - though I'd be interested to know the actual composition of the tanning agent used in China, and whether there are any regulations coming into force through health and safety. I am aware that the toxic method tanning in China and India is an environmental disaster and a serious health hazard to the workers.

 

For wearing watches, I buy good quality straps made in Europe - but, to be honest, I couldn't tell you whether these straps are from leather tanned in the traditional way or by more modern methods. I assume that more serious controls are in force in the West and, from what I've read, tanneries are far more tightly controlled.

 

With respect, I would add that the analogy with lung cancer and smoking is perhaps not quite in the same league as cancer and wearing a watch strap...

I agree that the analogy is not in the same league quantitatively, but qualitatively it is.

For me the problem is, that wearing cheap Chinese watches (in between wearing a Seiko) doesn't warrant buying a leather strap costing 3x that of the watch.  Thus, from now on, steel or rubber.

[anilv]

Since I don't usually wear the same watch more than a few times a month (i suspect that ths is the same with most of us here!) I don't really view this as a threat but thanks for highlighting it.

Ani

[bobm12]

Good to know...although I've always being partial to metal bracelets/bands.

[Ishima]

I'm sure quality leather band makers wouldn't use dangerous chemicals in dangerous quantities?

Perhaps I'm being naive but for all the song and dance Hirsch makes about how anti allergenic and safe and natural their straps are, then followed by the big price tag they have, I'd be surprised if they were in any way dangerous. (I normally wear metal bracelets, but have invested in one Hirsch leather strap)

Perhaps it's just a matter of buying things of genuine quality, I know quality doesn't come free, but if it concerns you that much...

Edited April 6, 2015 by Ishima

[bobm12]

 

Perhaps it's just a matter of buying things of genuine quality, I know quality doesn't come free, but if it concerns you that much

And rightly so, nowadays even quality things are made in China, and I don't think they cater for the difference in quality advertized...at least not too much.

[MichaelArcanjo]

The amount of hexavalent chromium salts in a bracelet is much less than that of a welding glove, motorcycle gloves and miscellaneous clothing items. the dermal absorption of this salt is considered low, many workers involved in leather improvement processes may have problems due to the amount of chromium salts involved, and different exposure routes. its dermal absorption is low, but wearing a leather bracelet from someone who wears a watch sporadically would limit such exposure even further. chromium salts can cause allergies, I've heard reports of allergies from workers who used scraped leather gloves for soldering, but I've never heard of wristbands, I think hexavalent chromium is a concern but I don't see a leather wristband as a possible source to do any damage! to other forms of exposure that are much more dangerous and aggressive, such as the processing of leather itself!

[kibbler]

I can pretty much guarantee that any leather that isn't marketed as veg tanned is chromexcel.  

There's plenty of chemicals used in the tanning process for both vegetable tanning and chromexcel tanning that I wouldn't want on my skin, that doesn't mean that wearing leather is going to give you cancer.

Edited March 16, 2022 by kibbler

[spectre6000]

Chromexcel is a name brand product line from Horween (an American tannery). What you mean is Chrome tanned. Sub that term in above, and you're correct.

Vegetable tanned leather takes several months to make. The hides are scraped (flesh removed), soaked in lye (unless the end product is intended to have hair, and then I'm not sure what is substituted here), scraped again (hair removed, and at this point you have rawhide for rawhide purposes and dog treats), then soaked in a tannin solution (typically a sort of tree bark tea) for 6-9 months. In chrome tanning, you swap the tannin solution for a chromium solution soak that only takes a few days. Vegetable tanned leather is then skived (shaved to thickness), and very occasionally dyed. Chrome tanned leather comes out blue and pretty ragged looking, so it's then almost universally dyed, waxed, embossed, etc. There is a hybrid tanning process (again, I think this is a Horween thing) that does the bulk of the tanning in the chromium solution, and finishes in the tannin solution. I'm not sure it does much more than give marketers something to talk about, but I've never really worked with it. The chrome tanning process is much harder on the leather fibers, and that makes them thinner, more fragile, and less dense. As a result, it's substantially inferior to vegetable tanned leather from a mechanical perspective, but much softer/more supple, and capable of a wider variety of colors/patterns/finishes. Vegetable tanned leather can also be embossed and dyed, but is also capable of tooling and takes oils much better. 

Back to the toxicity of it though... If you work in a tannery employing the chrome process (pretty much all of them), then yeah, exposure is almost certainly something you're concerned with. Beyond the very cheapest chrome tanned leathers (which will be obvious because it's really rough and fuzzy with longer "hairs" on the back), everything I've read over the years suggests whatever chromium is left in the leather is tightly bound and not going anywhere. I'm not sure how much is left, and I wouldn't go eating it (you could conceivably eat vegetable tanned leather, but there's really no nutritional value), but the exposure risk is nil or less.

Leather and tanning is a whole domain unto itself, and a dying one similar to watchmaking. It has its enthusiasts, artisans, and practitioners, but it's a thin crowd.

Fun fact that this crowd may enjoy: Patent leather (the shiny black stuff shoes are made of) these days is plastic, occasionally plastic coated leather. Back in the day, it was a super awesome process where the leather was rubbed repeatedly with a boiled linseed oil and some sort of black (coal, carbon, vine, etc.). The linseed oil polymerizes on exposure to oxygen, and forms a hard film. This film is then buffed, and you've got a shiny black leather with a hard wearing protective coat. The process is similar to the Japaning finish employed on many a cast iron tool of the era.