The wasted materials in question are in high demand — so much so that it isn’t actually the plastic and glass used in the manufacture of wearables that poses the biggest problem. Instead, according to the researchers, more than 70% of a device’s carbon footprint comes from the printed circuit boards (PCBs) housed within wearable devices — what we can think of as their “brain”, which powers and connects sensors, bluetooth modules, and the processors that collect measures like heart rate and steps. These PCBs are made using precious metals like gold, silver, platinum, copper, and cobalt — which, even if used in tiny quantities, require huge amounts of energy to be mined.
Then, most smart devices are powered by small lithium batteries — known for their intensive water and energy consumption in mining and production, and the fires they can cause if disposed of incorrectly in bins. Add to that the environmental damage and human rights abuses associated with the production of coltan, cobalt, and nickel — the essential materials for producing electronics — and the sustainability concerns linked to the production of wearables devices get more and more complex.
“These are all critical raw materials, and coltan, cobalt and nickel, for example, are all linked to countries that are having difficulty with civil unrest,” says Butler. “So broadly, the view is that most of the impacts of a product is actually in design, production, and getting it to market, but there is still another significant issue, which is around how you deal with it at the end of life.”
An open pit coltan mine in Rubaya, which produces 15 to 30% of the world’s supply of coltan.Photo: Getty Images
The Cornell researchers propose two solutions to this materials problem: that wearable tech companies’ engineers work on developing new chips made from more easily obtainable minerals like copper and aluminium, and that devices are designed to be “modular” — aka, out of distinct parts that can be replaced individually, without needing to replace the entire device.
Yet even copper, which moves the electric current around wearable devices, is growing increasingly scarce. Rapid consumption is expected to outpace supply, leading to a 30% deficit by 2035 — but experts say that better recycling of electronics could potentially meet the demand. Research by Recycle Your Electronics, for example, shows that UK households are sitting on 38,449 tons of copper hidden within unwanted and thrown-away electricals — an amount they estimate is enough to fulfil the UK’s annual demand for copper among tech.