Think you’re Well Travelled? You’ve got Nothing on your Shirt.

Where do your clothes come from? It’s a question that can apparently be answered with an awkward neck twist and a glance at a label.

In the UK, we make very few of the clothes that we wear. The majority are imported from a handful of export-oriented manufacturing countries, predominantly in Asia. In total, just over 20% of our apparel comes from China, followed by almost 11% from Bangladesh. A little lower down comes Cambodia, whose annual 40,000 tons account for just under 4% of the UK’s clothing needs.

At first glance, those seeing the word “Cambodia” on their label would seem to have a fairly good idea of where their garment has come from. Those curious enough to attempt a quick google might note that the vast majority of exports from here depart via the seaport of Sihanoukville in the South West of the country. At 9851 nautical miles (18,244 km), it’s a considerable distance for your shirt, blouse, or jacket to have travelled, but in reality, this is only the final act of a far longer story.

Unlike other garment exporting countries such as Indonesia, Bangladesh, or Vietnam, Cambodia does not have a primary textile industry and no integrated production capacity of its own. This means that Cambodian factories have to import intermediary textile materials for garment manufacturing from abroad, in many cases only providing the finishing touches to garments that are already partly completed. So, although your garment says it’s from Cambodia, it may also have come from further afield: a lot further.

During the last four years for which data was available, 2015-2019, 89,721 tons out of a total 161,455 tons of textiles that the UK imported from Cambodia can be indirectly linked to China’s direct supply of knitted fabrics, manmade staple fibres and cotton products to Cambodia. However, given China’s geographic size, we need to be more specific.

The majority of China’s garment industry is centred, for logistical reasons, in the coastal provinces of Jiangsu, Zhejiang, Guangdong and Hubei, which lie a relatively modest 1366 to 3231 nautical miles from their next stop in Cambodia. Raw material production, though, is a different matter. With some 84% of China’s domestic cotton production located in the far Western province of Xinjiang, the materials which are processed in China’s coastal factories must first complete a journey of between 3000 and 4300km as railroad freight: a distance roughly equivalent to that separating London and Lagos.

So before your garment labelled “Cambodia” arrives for the first time on Cambodian soil, the raw materials from which it is made have travelled between 5530km and 10284km, by a combination of sea or rail, adding a huge hidden carbon cost to the manufacture of the final garment. Yet this, again, is only part of the story.

Although China is the word’s largest grower of cotton, producing over a quarter of the world’s total crop, its status as the world’s premier apparel manufacturer means that demand considerably outstrips supply. China produced 6.07 million metric tons of raw cotton in 2018/19, but consumed 8.95 million, leaving a shortfall of over thirty percent of total usage.

China compensates for this shortfall with imports from across the globe, but the largest share of imports – accounting for 88% of the total – come from five countries: Australia, The United States, Uzbekistan, India and Brazil. The distances travelled by these imports vary from 1351km, between Tashkent in Uzbekistan and Xinjiang, to 35,688 km, between Los Angeles and Shanghai.

In this context, the label “Cambodia” on clothing purchased in the UK reflects only one stop along a vast global network of transportation. At a minimum, the materials contained in the t-shirt that you pick up from Gap, Primark, Walmart or Marks and Spencer, amongst many other leading retailers, has travelled 25,140km to reach the shop in which you buy it. At its maximum extent, however, it may have travelled up to 64,216km on its way to you: over one and a half times the circumference of the Earth.

A supply chain of this length is alarming in its own right, yet its broader implications are starker still. International shipping contributes roughly 3.5% of global greenhouse emissions, meaning that lengthy global journeys such as these hugely increase the carbon footprint of the goods they transport. Whilst a typical t-shirt might be expected to produce 6.75kg of carbon in the course of its production and sale – only 4.4% of which is emitted in transportation – these vast, hidden distances problematise the basic calculations we make about the sustainability of our apparel.

At its minimum extent, the transportation of a single Cambodia branded t-shirt would be expected to emit 47g of C02: 7.1% of the carbon emitted in its production and 50% more than the estimates used by sustainability advocacy groups such as the Carbon Trust. At its maximum, each t shirt will have been responsible for 103g of CO2 on its journey around the world. That’s over 15% of the total emissions created in its production and more than triple the average value on which carbon footprints are calculated.

In the context of a single t shirt, this may not seem like much, but scaling this up to the whole of the UK-Cambodia apparel trade puts these figures into stark perspective. Transporting the annual 40,000 tons of clothing the UK receives from Cambodia is generally estimated as producing 8304 tons of C02. Yet the true figures is between 13,400 and 28,770 tons. That’s up to 20,466 tons unaccounted for: the equivalent of 4,422 cars being driven for a year.  

Figures like these shine a light on the otherwise invisible systems that undergird our everyday lives, casting doubt on some of the broader assumptions we make about sustainability. The lack of transparency surrounding global supply chains means that many sources of emissions are either hidden or significantly underestimated. The circuitous journeys undertaken in the course of manufacturing processes speak to the scale of the challenge presented by trade networks in achieving sustainability. Their very complexity impedes detailed analysis and undermines accountability, concealing a significant proportion of carbon emissions from public view.  

Like so many of the items we purchase and use on a daily basis, the single country origin label sewn into a shirt is an illusion, just one stop along a global journey of assembly that is anathema to the sustainable production and a key stumbling block in the fight against climate change. Understanding this hidden geography is the first step to tackling the carbon footprint concealed within the hidden underwiring of our global economy.