There may be issues with the leather tanning method used to
manufacture handbags, shoes, watch straps and possibly even coats or jackets.
Not all leather tanning processes used to treat animal skins are safe.
Leather Tanning
Prior to the manufacture of fashion products, the animal
skins are treated in factories called tanneries. Leather tanning is the process
of turning animal hides into a workable fabric. Leather tanning makes animal more
durable and less like to deteriorate. The customary procedures of tanning use
an acidic chemical known as tannin, from which the tanning process acquired its
name. Tannin, the chemical used in the process, is actually the German word for
oak or fir trees from where tannin was first isolated. Leather tanning includes
a process which permanently changes the protein structure of animal skin, converting
hide into different types of leathers.
Leather tanning procedures have advanced significantly since
the ancient generations and currently leather tanning can be achieved with
either vegetable or mineral techniques which use of chrome, alum, zirconium,
titanium, iron salts or other minerals.
Rawhide
The word rawhide relates to a skin which is not tanned, but treated
by cleaning the flesh, fat and hair, and then by treating it with chemicals
known as liming which uses a solution of lime; or bucking which uses wood ash
(lye). After the chemical treatment the hide is scraped over a beam with a fairly
blunt knife and then dried.
This same process can also be used as a preparation step before
the leather tanning process so as to cleanse the fibre network of the animal skin
to let the leather tanning agent penetrate without difficulty. Another process used
to unhair, degrease and desalt the animal skins prior to leather tanning, is to
soak them in water for 6 hours to 2 days. To prevent damage to the skin by
bacteria and fungi, biocides and fungicides are added to the water.
Dying
Dyes are added during leather tanning to get a variety of attractive
colors. In a visit to Morocco I was intrigued by the Moroccan Leather Tanning
Vats located on the outskirts of the old city of Fez. These vats have been in
use for centuries. Leather tanning has always been thought of as a decidedly
noxious and truly smelly skill. The leather tanning vats were typically found
on the fringes of a town. The odors were due to a mixture of urine, animal faeces
and decaying flesh. In fact, leather tanning by these old traditional methods yields
such rotten smells that tanneries still using old systems are still positioned as
far out as possible. The ancient craft of leather tanning and dying is handed down
from father to son and the craft is kept within the family for generations.
Toxic Chemicals
In order to boost leather tanning procedures, some tanneries
use toxic chemicals which are cheaper and faster than tannins. These include
·
Mercury based biocides (Banned since 1980)
·
Pentachlorophenol (PCP’S) (Banned since 1980)
·
Cyanide
·
Chromium Salts
Chrome Leather Tanning Methods
Chrome leather tanning is a nineteenth-century development, and
was implemented because it was an efficient, quick and inexpensive way of
treating animal skins. The ease and cheapness of this technique has made it the
economical choice of the mega-brands. A vast proportion of luxury goods manufacturers,
as well as contemporary brands have chosen to use chrome leather tanning over
other traditional techniques.
So why is chrome leather tanning an issue?
Chrome leather tanning is an issue because of its
environmental impact. Chromium III sulphate used in chrome leather tanning is
recognized as the most efficient and effective agent to treat animal hides.
Chrome leather tanning is significantly quicker than vegetable leather tanning
and it produces a really stretchable fabric which is great for making handbags
and other leather goods.
Chromium III compounds used in leather tanning are
significantly less toxic than Chromium VI. However chromium III oxidizes to
chromium VI by boiling and sun-drying. Chromium VI is a very toxic heavy metal
which is both carcinogenic and environmentally harmful. Unfortunately chromium VI
is often found as a waste product from leather tanning. It has been detected in
food chains and in the water supplies of both developing and developed
countries. When chromium VI leaches into the soil it is absorbed by vegetation and/or
ingested by animals. Nearly 25% of chickens in Bangladesh are contaminated by dangerous
levels of chromium VI which causes a major national health concern. Toxic
chromium salts residues in handbags etc. may affect your health.
Luxury brands use chrome leather tanning to manufacture
handbags and shoes without appreciating the environmental impact, nor the well-being
of consumers. But as long as people continue to buy chrome-tanned goods, there
is minimal motivation for luxury brands to move to the safer vegetable process which
takes longer, is more costly, and does not as successfully cover up low quality
skins.
Vegetable Leather Tanning
Vegetable leather tanning is a slower and more costly practice,
but it is much safer for the environment and safer for you! This is the leather
tanning process you should demand. Vegetable leather tanning is used by Conti of
Tuscany one of my suppliers of both men and women's exquisite Italian handbags.
Vegetable leather tanning uses the traditional tannin technique.
Tannin is found naturally in the bark and leaves of many plants such as
chestnut, oak and other trees. Tannins bind to the collagen proteins in hides
and they become less water soluble, and more resistant to bacterial contamination.
This process also causes the hides to become more flexible. Hides are stretched
on frames and immersed for several weeks in vats of increasing concentrations
of tannin. Vegetable tanned hides are used for the manufacture of handbags, luggage
as well as furniture
Leather Tanning Using Other Minerals
Other chemicals such as alum, zirconium, titanium, iron
salts can also be used to treat skins. This method is eco-friendly and are known
as “wet white” whereas chrome tanning produces a “wet blue”.
Goods That Last a Lifetime
Leathers last for a lifetime. However, many luxury brands
now manufacture goods to a much lower standard. Some luxury handbags which cost
over a $1500, will last only last for a few years before they need to be repaired.
Others will simply fall apart. Cost-cutting tricks in the manufacturing process
include:
- Makers compromise on the quality of leather tanning process
- Mega-brands use chrome leather tanning rather than more eco-friendly approaches
- The edges of handbags are finished with acrylic varnish which cause the material to crack within a couple of years. Techniques such as turned edges or burnishing which are more time-consuming should be employed because they result in a product that last for decades
- Manufacturers use poor quality hardware on their products, such as white metal rather than solid brass or plated steel
- Modern stitching techniques are poor quality. They no longer tend to use traditional saddle making techniques which are stronger and more robust
These cost cutting actions have damaged the quality of the designer brands. Handbags cannot be called if the brand has compromised on manufacturing
processes and produce items with inferior quality. A price tag on its own does
not determine if a product is luxury or not. Some brands, even some of the most
renowned names in the industry, have tainted their popularity by driving volume
production rather than quality.
It is far better practice for the mega-brands to use techniques
and procedures that mean the products will stand the test of time. The responsibility
to promote change lies in the hands of the fashion houses and luxury brands who
need to be more focused on the environment rather than financial results. It
would be a smart move for companies to label their garments with the leather tanning
method used so that the consumer can make an informed choice.
