A new study has revealed that demand for healthcare electronics could approach 2 billion units per year by 2050. But unless measures are taken to reduce the environmental impact, these devices could cumulatively generate more than a million tons of electronic waste and 100 million tons of carbon dioxide by 2050, according to the study by the University of Chicago and Cornell University.

“Our hope is that this framework will guide the responsible development of next-generation wearables,” said Chuanwang Yang, postdoctoral researcher at UChicago and first author of the study.

The study revealed that as electronics have gotten smaller and more flexible, they’ve been incorporated into more uses in the field of healthcare. The ability to continuously track a patient’s blood pressure, glucose or heartbeats can help doctors and caregivers keep them stable and avert crises. 

Environmental impact

But most of these devices are designed to be disposable—even more so than consumer electronics, in many cases, since longer-term use can pose the risk of performance degradation or infection. 

The laboratory of Bozhi Tian, professor of chemistry at UChicago, found little research had been done on this ballooning market and its potential environmental impact. They joined forces with the Cornell University Prof. Fengqi You’s group to tackle this challenge, according to a press release.

Demand for healthcare electronics accelerating

“As this transformative field accelerates, society still lacks a clear understanding of its full environmental implications,” said Yang.

First, the team modeled global use of these devices. Extrapolating from current trends, by 2050, the demand for healthcare electronics worldwide could be 42 times higher than today, accounting for about 2 billion units annually. Next, the team developed a framework for measuring the environmental footprint of these devices, as per the release.

A comprehensive analysis is important but difficult, because it must pull together many threads. Tian’s team incorporated every part of a device’s “life cycle”: from the impacts of the mining required for ingredients, to the energy used in manufacturing the devices, all the way to the waste created after disposal. They judged carbon footprint, toxicity of the materials and electronic waste. 

The team revealed that even though each chip only needs a small amount of the metal, mining consumes a lot of energy and produces a lot of waste.

The study found that the printed circuit board—the “brain” controlling the device’s electronics—dominated the device’s environmental impact by a wide margin. 

“More than 70% of the carbon footprint of a device comes from the circuit boards,” said Tian.

When people discuss sustainability in devices, Tian said, the conversation is usually about plastics, or perhaps the sensors. But that only turns out to account for a small fraction of the total. For example, even if all the plastic in the devices were to be replaced with biodegradable versions, the impact only lessons by 3%, according to the team. 

The integrated circuit, meanwhile, requires precious metals like gold. Even though each chip only needs a small amount of the metal, mining consumes a lot of energy and produces a lot of waste.

The team identified two major potential solutions to lower the devices’ carbon footprint. The first is for chemists and engineers to develop new chips that can use more easily obtainable minerals, such as copper or aluminum, instead of rarer minerals like gold. Copper and aluminum are less stable than gold, which is why they haven’t been used in chips. But there may be ways to design around this problem, as per the study.

“A lot of people assumed you would have to sacrifice performance if you use more reactive metals, but our analysis suggests it should be OK if you provide extra protection for the circuitry,” said Tian. 

The second major solution is to design the devices to be modular. “More than 70% of the carbon footprint of a device comes from the circuit boards,” said Prof. Bozhi Tian.