Leather-Tanning with Chromium

Chrome is used in about 90% of leather tanning operations worldwide, and its use has long been a concern in regards to its potential environmental impact.  Trivalent chromium, the form most commonly used in tanning, is naturally occurring and essential for good health.  Under certain conditions, however, trivalent chromium will oxidize and turn into hexavalent chromium.  Hexavalent chromium is carcinogenic and can pose severe health concerns for humans, animals, and the environment.

While there are other methods of tanning, such as vegetable tanning, chromium is used most of all because it produces leather that is softer and suppler than the other methods, and doesn’t discolor or lose its shape as much in water. Chromium-tanned hides also pick up more color during the dying process. For more information on how leather is made, and my source for this chromium-tanning information, click here.

Acute effects of hexavalent chromium exposure include irritation to the mouth, throat, lungs, and nose (if inhaled); skin irritation and allergic reactions (if the skin was exposed); and digestive problems, kidney damage, or liver damage (if consumed contaminated food or water).  Long-term effects of chromium exposure include lung cancer, lung irritation resulting in asthma, liver or kidney damage, impaired immune system, and reproductive problems.  For a chromium fact sheet provided by the Wisconsin Department of Health Services, and my source for the health effects of chromium, click here.

Many tanneries worldwide have strict regulations for purifying water used during the tanning process of any residues or pollutants, but a very large portion of the tanning industry operates from developing countries without such strict regulations, especially in regards to wastewater. As you can see from the chart below, the regions most impacted by chromium pollution from tannery operations is South Asia, Central America, South America, and Africa.

2011 - Population estimates are preliminary and are based on an ongoing global assessment of known polluted sites.

In addition to potentially toxic wastewater, some tanneries also produce large amounts of solid waste that contains chromium.  In some areas, these pollutants are the reason that all nearby surface and groundwater systems are contaminated with severely high levels of chromium.

For more information regarding chromium pollution deriving from tannery operations, and my source for these images and accompanying data, click here.

The People of Hazaribagh Leather

 Leather scraps laid out to dry on top of a landfill near Hazaribagh Photographed by Arantxa Cedillo

Hazaribagh is made up of an estimated 150 tanneries, somewhere between 90-95 percent of all Bangladesh tanneries. This industry rakes in roughly $663 million for the country, according to a Human Rights Watch report, and yet the local residents are living in slums that kill them. Workers of the tanneries suffer from*: 

• Premature aging
• Discolored, itchy, peeling, acid-burned, and rash-covered skin
• Fingers corroded to stumps
• Aches, dizziness, and nausea
• Disfigured or amputated limbs
• Elevated cancer rates
• Respiratory diseases

*Health conditions described by Human Rights Watch 

Many of these conditions are the results of repeated exposure to hazardous chemicals. While each of these chemicals are dangerous, a number of them are more innocuous, such as: formaldehyde, azocolorants, and petachlorophenol. All of which are known or potential human carcinogens, the health effects of which may only manifest years after exposure.

Photographed by Arantxa Cedillo Hazaribagh's Slums beside an open gutter that channels polluted effluent from nearby tanneries.

The Human Rights Watch completed interviews with as many of the Hazaribagh tannery owners as time permitted in addition to current and former employees, government officials, NGO's (non-governmental officials), and tannery association representatives. After speaking with each of them they affirmed that no tannery in Hazaribagh had an effluent waste treatment system. NONE of the 150 tanneries. 90-95 percent of all of Bangladesh's tannery industry has no waste treatment system to stop documented poisonous industrial waste products from getting into the waterways. The government of Bangladesh estimates that 21,600 cubic meters of untreated effluent is released every day. This surpasses their own regulations by many thousands of times in many instances.


The people of Hazaribagh's leather are suffering in poisoned poverty. To learn more about the disease of Hazaribagh click here

Leather Alternatives

India’s Holy Cash Cow

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ISSUE 434

Western demand for leather exacerbates inhumane treatment of animals

David Joshua Jennings

It is said that the cow is the mother of all civilization. Of all the images of India, few are more enduring or endearing than that of the cow, revered by Hindus for its life-giving milk, roaming free in the city streets. But this postcard picture belies a darker truth. India is the world’s largest exporter of leather. And whilst the killing of cows is banned in all but two states, in the world of the illegal leather trade, animal rights abuses are rife as the country cashes in on its most sacred symbol to meet the Western desire for leather.

‘According to many local council laws, slaughterhouses need to be licensed,’ says Nilesh Bhanage, head of the Plants and Animals Welfare Society. ‘But many of the slaughterhouses don’t have licences.’ Despite stringent laws in place to protect the rights of animals, illegal slaughterhouses remain unmonitored and unregulated. A source from one of India’s leading exporters of leather handbags to Britain, who asked to remain anonymous, revealed that illegal leather is commonly used. ‘It is often cheaper that way. It is not a transparent industry. There is a lot that goes on behind the scenes to cut costs and make ends meet. Animal rights are greatly compromised.’ One leading leather technologist has estimated that as much as 75 per cent of all Indian leather could come from illegal sources.

The slaughter of cattle is permitted only in West Bengal and Kerala and it is illegal to transport cows for slaughter across state borders. Neither state boasts a significant cow population, yet hundreds of thousands of cows are brought there from all over India to be killed. ‘Traders bribe officials to look the other way as they pack the cows into vehicles in such high numbers that their bones break, they suffocate and many die en route to slaughter,’ explains Poorva Joshipura, director of People for the Ethical Treatment of Animals (PETA) Europe. ‘Thousands of others are made to walk – often without food or water. If they collapse from exhaustion, herders break their tailbones or smear chilli pepper and tobacco in their eyes to make them walk again.’

‘The treatment of animals in both licensed and unlicensed slaughterhouses is the same,’ Joshipura continues. ‘Basic animal protection laws are totally ignored. Animals are dragged into slaughterhouses before they are cut open – often with dirty, blunt knives and in full view of one another – on floors that are covered with faeces, blood, guts and urine.’ Some animals, she says, are even skinned and dismembered whilst still conscious.

Britain is the third largest importer of Indian leather. Despite the mounting evidence of ill-treatment of cows, leading British retailers continue to use Indian leather in their shoes, garments, handbags and furniture. While upmarket department store Harrods refused to comment when asked what it was doing to ensure illegal leather did not end up in its products, Marks & Spencer 10 years ago became ‘the first major retailer to ban the use of cow hides sourced from India,’ according to its deputy head of corporate PR. Some US retail giants, such as Kenneth Cole and Liz Claiborne, have followed suit by boycotting Indian leather entirely.

But the inhumane treatment of India’s once sacred cows will continue as long as there is a demand for leather. As animal welfare legislation has been enforced in the West, cruel and destructive practices have been exported to the developing world. The answer, for Maneka Gandhi, former Minister for Animal Welfare and one of India’s leading animal rights activists, is clear. ‘Don’t buy leather,’ she says. ‘The best thing you can do to help these animals is to stop wearing them.’

Ambika Hiranandani, Roland Miller McCall and Salman Shaheen

- See more at: http://newint.org/columns/currents/2010/07/01/india-leather-cows/#sthash.zbkZpgrI.dpuf

The appropriate wellbeing of animals used to make leather is another factor that must be considered.  Even though there are some humane ways to use leather as a by-product, like in the case in India there are also horrible ways as well. Leather doesn’t only effect animals, but can be dangerous to humans with exposer to chemicals. Chemicals that are used to process the leather can cause harm to the environment and can pollute the air.  Let’s examine some alternatives that are safer for humans and animals.

There are alternatives to leather that do not involve animals and can have added benefits that leather doesn’t have. Pleather is way to avoid animal cruelty and has features leather does not have like it is more resistant to deposing and it can be washed easier than leather. Poromeric imitation leather is lighter and more breathable to prevent perspiration on a warmer day. Koskin is artificial leather that is good for laptop and technology cases. If more awareness is spread about the issues concerning leather, then more designers might switched from leather to another alternative.

Tannery Pollution's Effect on Plant Life

The leather tanning industry is a major source of pollution such as tannery waste-water. These waste by products pose severe environmental risks on our water and environment due to its chemical content. For example in a study completed by Mwinyihija et al. In 2005 and 2006 it was shown that Chromium-- an inorganic transition metal used in the tanning process, and exists, “in several oxidation states...with trivalent and hexavalent species of chromium being the most common forms”, have profoundly negative effects on the cellular compounds of organisms.

Plants that are grown in chromium concentrated substrates showed significant stored levels of the metal inside the plant's cells-- mostly in the root systems. The amounts of, “chromium accumulated in plant tissues resulted in significant inhibition of chorophyll, protein contents and in vitro nitrate reductase activity in test plants” (Mwinyihija 29). In layman's terms, Chromium compounds that are frequently used in the production of leather are deadly to plants and ultimately leads to reduced growth in the roots and photosynthesis components that stunt and kill the plant.

The effluent waste-water flows out of these tannery establishments and into the surrounding environments to negatively impact the ecosystems. In the video below it explores the environmental effects that a tannery in Bangladesh is having on the community, waterways, and environment.

References:

Mwinyihija, Mwinyikione. "Chapter 2: Main Pollutants and Environmental Impacts of the Tanning Industry." Ecotoxicological Diagnosis in the Tanning Industry. New York: Springer, 2010. 17-31. Print.

The Leather Industry: Hazardous To Both Humans and the Environment

Image:  Tannery in India.  Credit: © Goran Bogicevic

© Goran Bogicevic

When the average U.S. citizen hears the word “leather”, they probably think about nice jackets, shoes, purses, etc.  Little thought would be specifically given to the leather itself or how it goes from being the raw hide of an animal to a finished product.  Most people don’t realize the hazards associated with the leather industry and the impact it has on humans and the environment. 

According to PETA, in its article "Environmental Hazards of Leather", the chemicals used to turn skin into leather, including formaldehyde, coal-tar derivatives, arsenic, and cyanide-based finishes to name a few, are very dangerous and have been linked to various types of cancer.  Most leather in the U.S. is tanned using chromium, a chemical considered hazardous by the Environmental Protection Agency.

The tanning of leather also takes a big toll on humans.  The Centers for Disease Control and Prevention found that leukemia incidents among residents near a Kentucky tannery were five times the national average, and studies of tannery workers in Sweden and Italy found cancer risks being 20-50% higher than expected.

For a detailed article on the different forms and types of leather, and the leather production process, click here.
For a step-by-step introduction to the leather production process, accompanied by visuals for each step, click here.