Are cotton T-shirts a sustainable product? originally appeared on Quorathe place to gain and share knowledge, empowering people to learn from others and better understand the world.

Answer by Suzanne Sadedin, evolutionary biologist, on Quora:

Are cotton T-shirts a sustainable product? 

Yes, but really no.

Cotton is sustainable in the sense that it’s a natural fiber produced by plants. We can always grow more of it; it doesn’t intrinsically require resources that we can’t replace. And it’s biodegradable; it breaks down in a fairly short time once discarded and leaves no trace.

This contrasts with synthetic fibers like polyester, which are generally produced using non-renewable resources (fossil fuels) and do not biodegrade effectively. Instead they shed huge numbers of particles which create very long-lasting pollution.

However, in practice cotton production is unsustainable. Between 1989 and 2014, the Aral Sea has nearly completely dried up. You can’t call your crop sustainable when it’s largely responsible for drying up an entire sea.*

Cotton is touted as a drought tolerant crop, but in reality, as the National Cotton Council of America notes, its “extreme sensitivity to adverse environmental conditions is unique”. Competitive industrial-scale yields are only obtainable with precise watering schedules. Consequently, cotton production is water-intensive: it can take 2700 liters to produce a single T-shirt. World cotton production between 1997 and 2001 used 256 gigaliters of water. And since water and cotton travel and are consumed across national boundaries, it’s almost impossible to police:

About 84% of the water footprint of cotton consumption in the EU25 region is located outside Europe, with major impacts particularly in India and Uzbekistan. Given the general lack of proper water pricing mechanisms or other ways of transmitting production-information, cotton consumers have little incentive to take responsibility for the impacts on remote water systems.

Industry claims that better water management has addressed this problem are belied by numerous studies showing ongoing increases in consumption and declines in groundwater (e.g. thisthisthis, and this).

But the problem is more than water usage. For industrial-scale production, cotton crops need to be treated with extraordinary quantities of pesticides and herbicides. Despite efforts to reduce this via genetic engineering and other methods, a 2017 report shows cotton production is still the fourth largest consumer of agricultural chemicals. In many places, reductions in pesticide use have not been sustained and/or herbicide use has increased.

2014 study estimated that pesticides in the United States cause $9.6 billion of damage annually. The US is only the world’s third biggest cotton producer, after India and China, which have generally weaker environmental regulations. Numerous studies of cotton-producing communities show “impairment of the nervous system, lower neurobehavioral performance, delayed puberty, breast milk contamination, blood abnormalities as well as many acute symptoms such as nausea, respiratory problems, dizziness and convulsions.” According to fashion designer and environmentalist Katharine Hamnett, cotton-related pesticide use causes “350,000 farmer deaths a year and a million hospitalisations.”

As a 2015 paper put it:

In biotechnology, agricultural economists have pushed forward agendas without understanding the ecological bases of the crop production problem and in the process they often wrongly filled the information gaps… The adherence to doctrines that exclusively accept or select observations and disregard fundamental ecological principles for supporting scientific claims imposes serious limitations on their conclusions and has been a hindrance to progress in agricultural research [85]. In India and elsewhere, subsistence farmers often lack a clear understanding of pest control issues that trapped them on a pesticide treadmill (e.g., [11]) and now onto a biotechnology treadmill [33] and that ignores the impending collapse of ground water levels for irrigated cotton [26]. Subsistence farmers, especially in areas with low but high variable yields can ill afford the high costs of industrial farming technologies that contribute to bankruptcy and in some suicide cases.

And that’s not even considering the environmental impact of dyes and shipping.

So: which fabrics are environmentally friendly? In short, none. Some industry sources say fashion is the world’s second biggest polluter.

Organic cotton uses less pesticides. But it needs even more water and land than conventional cotton because more of the crop is lost to pests. Plus, in many places, organic producers use “natural” pesticides which aren’t necessarily less toxic than synthetic ones.

The most-touted alternative is hemp. Compared with cotton, hemp uses one quarter the water, very little pesticide, and about half the land. But its production is labor-intensive, requires specific soil conditions and is subject to a lot of regulation. Overall, hemp production uses slightly more energy than cotton.

So how can we be clothed yet environmentally responsible? Simple.

Opt out of the fashion industry. Buy high-quality durable clothes that you will be happy with for many years. And/or buy them second hand.

That might seem like a big sacrifice, but it isn’t necessarily. Second hand clothes come in a much wider range of styles than current fashions, so you actually have more choices. They’re often better quality, and they’re invariably cheaper.

There’s a silly social stigma against wearing the same clothes repeatedly. But if Steve Jobs, Mark Zuckerberg, Barak Obama, and Albert Einstein all did it, it can’t be that bad of an idea, can it?

*Rivers that feed the Aral Sea were diverted in the 1960s by the USSR, primarily but not exclusively for cotton irrigation. The Aral Sea has been drying up ever since. See: Shrinking Aral Sea

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