The Dark Side of Wearables: What Do We Do With Devices When They Die?

These discarded materials are in such high demand that it’s not actually the plastics and glass used to make wearables that are causing the biggest problem. Instead, according to researchers, more than 70% of a device’s carbon footprint comes from the printed circuit board (PCB) in a wearable device, which we can think of as the “brain” of the device, providing power and connectivity for sensors, Bluetooth modules, and processors that collect data such as heart rate and step count. These PCBs are made from precious metals like gold, silver, platinum, copper and cobalt, which require a lot of energy to mine even in small amounts.

Most smart devices, then, are powered by small lithium batteries—which are known to consume large amounts of water and energy in mining and production processes and can cause fires if not properly disposed of in the trash. In addition, environmental damage and human rights violations related to the production of coltan, cobalt and nickel (the basic materials for the production of electronics), and sustainability issues related to the production of wearable devices are becoming increasingly complex.

“These are important raw materials, such as coltan, cobalt and nickel, that are relevant to countries struggling to deal with civil strife,” Butler said. “Broadly speaking, the view is that most of the impact of a product is really in terms of designing it, producing it and getting it to market, but there’s another big question of what to do with it at the end of its life cycle.”

An open-pit coltan mine in Rubaya produces 15% to 30% of the world’s coltan supply.Photo: Getty Images

Cornell University researchers have proposed two solutions to this materials problem: Engineers at wearable technology companies are working on developing new chips made from more readily available minerals like copper and aluminum, and devices are designed to be “modular”—that is, made up of different parts that can be replaced individually, without replacing the entire device.

However, even copper, which carries electrical current around wearable devices, is becoming increasingly scarce. Rapid consumption is expected to outstrip supply, leading to a 30% deficit by 2035, but experts say better electronics recycling may meet demand. For example, research by Recycle Your Electronics shows that UK households have 38,449 tonnes of copper hidden in unwanted and discarded appliances – an amount they estimate is enough to meet the annual demand for copper from the UK tech industry.