Tanning with Chrome and Metal Free: differences and reflections
Many ask me for information on the types of tanning and their environmental sustainability. Is tanning ever eco friendly?
In this post I will try to explain in the clearest and most simple way the various types of tanning, their fundamental characteristics and their sustainability.
European tanners must follow European Union regulation REACH (Registration, Evaluation, Authorization and Restriction of Chemicals) a slightly “old” regulation that doesn’t satisfy the modern requests of the market by fashion operators!
Tests are being done to move on from Reach regulation and try to do Green Dressing, an organic vegetable tanning. Saga Fur has been working on it since 2011 with a German tannery. The project is still in progress.
Let’s start with the much-discussed chrome tanning.
Is Tanning with Chrome dangerous?
Well there are two types of chromium with which it is possible to tan skins: hexavalent chromium CHROME VI and trivalent chromium or CHROME III.
Chrome VI is really dangerous and is not used just for tanning but also in other industrial sectors.
Chrome VI has been classified by IARC (International Agency for Research of Cancer) as carcinogenic for man in class I.
Practically like Eternit, that we covered houses, huts, the kennels of our beloved pets with, created agricultural dividers and other things which caused us lung cancer in general silence from who obviously knew that it was highly cancerous.
If anyone has been in a tannery, our tanneries I mean not abusive ones or in posts without rules, they will certainly have asked themselves how come tanners don’t use masks despite all that stench and those fatal agents.
Why? Because our tanneries use Chrome III, which is a nutritious substance that is essential for humans.
Lack of Chrome III can cause pathologies like diabetes and heart problems.
For humans the main way to ingest Chrome III is through the food that contains it.
It seems eccessive to me to make a shopping list when we’ve got Google.
Now, I won’t tell you that drinking a bottle full is restorative but evidently it does not provoke all the damage that people are saying if it is handled and treated adequately.
Even water can be poisonous if we drink too much of it!
By duty of information it’s true that because of the oxidation processes of CHROME III during careless transport of skins, in careless prolonged re-tanning processes, in case of inadequate treatment of waste, can be turned into CHROME VI.
Let’s talk about extreme cases.
Sure, there are people that go 200 kilometres an hour in a residential area.
Thankfully, it’s not the norm
To deal with these inconveniences and for the chromium free tanning fan club there is metal-free tanning that includes all the tanning that does not use heavy metal but in which chromium has been replaced by other reagents.
ATTENTION: read carefully. I didn’t write that in METAL-FREE tanning there are only “organic products”. I wrote that there are no heavy metals.
Which are these tanning agents that are alternative to chrome?
There are synthetic tannins (generally products of the condensation of formaldehyde) combined with vegetable tannins (present in and obtained from plants), glutaraldehyde (a disinfectant used also in the hospital field this does not mean that you can drink or sniff it) and minerals, like aluminum (we also make pans to cook with it but depending on how it is treated it can be more or less toxic) and zirconium (it is found in nature and we use it for the setting of dentures but can become very dangerous even catch fire by itself) and titanium (even if we find it in many drinks as an additive it doesn’t seem so safe).
I don’t want to write a chemistry essay so click on the links above if you want information on tanning agents alternative to chromium and know how they can be dangerous for health.
The next types of tanning are classed as Metal-Free but are only for skins destined to furriers so mainly of bovine origin, sheep and for exotic skins that have nothing to do with those of fur.
Tests are done continuously on skins for fur but there are still problems being resolved because the hide of the skins remains too rigid.
The name derives from the characteristic nearly white color that the hide takes on after being tanned.
You know that I love supporting innovation and love start-ups above all the innovative ones and those that really improve everyone’s standard of life.
Crossing was founded by Dr. Beghetto of the University Ca’ Foscari di Venezia. The objective is to reach production on an industrial scale of cross-linking activators.
ACL unite a series of organic and / or synthetic materials without leaving a trace in the final product: cool, huh?
This technology can be applied for the production of metal-free, nontoxic hide, food packaging, varnish and more.
So WELL DONE to you Dr. Beghetto and to all your young team!!!
The studies of Crossing are still covered by patents so even if I wanted to go deeper I couldn’t: in due course I have no doubt that I will rush to write abll about it, and share it with you.
At the top of the scale the oldest tanning: vegetable tanning.
It has a two-hundred year history that has been passed down from generation to generation. The recipes are jealously guarded by father and son and are based on vegetable extracts like mimosa and cork.
Vegetable tanning is an ancient art and is the healthiest way to tan. It has warm colours but it does has disadvantages: the hide stains easily during the tanning process, it takes a lot of time and the colours that can be obtained are really limited.
I don’t know how much this type of tanning can be loved by the fashion world.
Yes, because despite the indisputable efforts that the tanning industry is making in terms of sustainability it is also true that it must adjust to the requests and rhythms of the faster and faster world of fashion.
A fashion that calls for faster and faster times and more and more competitive prices and so struggles to go arm in arm with vegetable tanning.
A tanning that is completely free from chemical products.
To be considered metal-free as required by the law UNI EN 15987:2012 of 2012 the concentration of the single tanning metals (CHROME, ALUMINIUM, ZIRCONIUM, TITANIUM and IRON) must be less than 0,1% so if you don’t tan skins yourself and you ask serious tanneries and you will see that the problem should not exist.
The main subject of discussion still regards materials used for tanning but also the energy used and the disposal of the waste waters are important in terms of environmental sustainability so I think it is fundamental to talk about it.
We wrote this part of the post following UNIC information website.
In the tanning industry a great use of electrical and thermal energy and water is made. The first is for the working of the machines, the second to heat the waters for the process and the tunnels where the skins are dried, the water for the baths that are used to tan.
Investments of Italian tanneries in technology and research to reduce the use of natural resources (water, methane) or transformed resources (electrical energy, chemical products) are continuing.
In 2016 for example, new cogeneration systems were set up (they allow the production of mechanical energy and heat with an evident great saving of electrical energy) and systems optimized to dose chemical products and water to perfection allow great water savings and the disposal of fewer chemical products.
To dispose of water most tanneries use specialized cooperative purifiers that are structures specialized for purifying water that companies use. The waste waters are usually pretreated by the tanneries, let’s say diluted.
There are companies specialized in the installation of systems to purify waters.
At the end of these combined procedures they let the water back into nature with safe qualitative characteristics.
As regards the emissions into the atmosphere even here cutting-edge technologies are used that have to conform with the very severe laws, both national and European, like IPCC (Intergovernmental Panel On Climate Change)
The IPCC is a scientific organism composed of scientists from all over the world that objectively evaluate climate change and the state of the ecosystem. On their considerations the standards that plants must have are evaluated, what is harmful or not for our planet and the various parameters that the emissions into the atmosphere must respect. Telling you everything in a single post regarding such a wide subject was impossible, but I think I have said a lot.
I promise to keep looking into the subject and keep you informed, if you have questions please write.
I advice you to read this post about Fake Fur
The cover photo is from Corriere Alto Milanese