The Environmental Impact of Smartphones: Understanding Their Life Cycle

Smartphones have become one of the most essential tools in modern life, serving as communication devices, entertainment hubs, productivity aids, and even health trackers. However, while convenient, smartphones contribute significantly to environmental issues. In 2022, global electronic waste (e-waste) reached a record 62 million tons, with 5 million tons coming from small IT and telecommunication equipment, including mobile phones, laptops, GPS devices, and routers. Alarmingly, only 22 % of the total e-waste was formally collected and recycled [1].

To make more sustainable choices when purchasing or disposing of a smartphone, it is crucial to understand its life cycle, which consists of five key stages:

1. Product Design and Sourcing Materials

The design phase plays a crucial role in determining a smartphone’s durability, longevity, and environmental footprint. Essential materials such as iron, gold, aluminum, lithium, copper, rare earth elements (mainly neodymium, praseodymium, dysprosium, gadolinium, and terbium), and plastics are necessary for the components of high-tech electronics, enabling the device’s advanced functionalities.

However, extracting these resources has significant environmental consequences, including greenhouse gas emissions, depletion of natural resources, and pollution. Opting for alternative or reduced materials can help conserve energy, protect ecosystems, and reduce environmental harm.

2. Manufacturing

Once the raw materials are extracted, they must be transported, processed, and assembled into smartphone components like screens, circuit boards, and batteries. These components are then refined and put together to form the final product.

According to a study by N. Lövehagen and colleagues, manufacturing a single smartphone generates approximately 50 kg of CO₂ equivalent (CO₂e), making it the most environmentally damaging stage of the life cycle [2].

3. Transportation and Distribution

After production, smartphones are packaged and shipped to retailers and consumers worldwide. The packaging industry is changing due to concerns over plastic waste, which contaminates the environment, pollutes oceans, harms wildlife, and introduces microplastics into living organisms. As a result, regulatory measures have been implemented to minimize plastic use, encourage recycled materials, and promote sustainable packaging alternatives [3]. Common eco-friendly packaging materials include responsibly sourced wood-based products, paper, carton, bamboo, bagasse (sugarcane), and other plant-based alternatives such as rice, corn, and wheat fibers.

Transporting smartphones globally involves air, sea, and land shipping. Among these, air transport is the most carbon-intensive, producing 155 million tons of CO₂ while moving 303 billion tonne-kilometres of cargo [4]. In contrast, sea transport, although emitting a higher total of 657 million tons of CO₂, moves a significantly larger volume, 101,486 billion tonne-kilometres, making it a more efficient option.

Land transport is divided into rail (170 million tons of CO₂, moving 10,842 billion tonne-kilometres) and road transport, including trucking and urban deliveries (2,230 million tons of CO₂, transporting 26,807 billion tonne-kilometres). As a result, companies prioritize sea and land transport over air travel to minimize carbon emissions.

4. Usage

The usage phase of a smartphone refers to the period when a person actively uses the device. On average, a user keeps a smartphone for about two to three years before replacing it. The main reasons for replacement include:

Aesthetic obsolescence – Upgrading to a newer model for appearance or design reasons.
Technical obsolescence – The phone becomes slow, damaged, or has poor performance.
Functional obsolescence – The phone is no longer compatible with the latest operating system updates [5].

5. Collection and Recovery

The final stage of a smartphone’s life cycle occurs when the device is no longer in use. The way a phone reaches its end-of-life depends on the reason for its replacement. Around the world, old phones are collected mainly through two methods: trade-in programs and independent waste collectors or recycling companies.

Trade-in programs allow consumers to return their old smartphones to the manufacturer in exchange for money or a discount on a new product. This system encourages responsible disposal and reduces electronic waste.

Independent waste collectors and recycling companies operate similarly, offering payments based on the phone’s condition and value. Once collected, old smartphones follow one of three main processes: reuse, refurbishment, or recycling.

Reuse

Reuse is the most straightforward process. If a phone is still functional, it goes through cleaning, minor repairs, and depollution (removal of harmful substances) to make it suitable for reuse. Many recycling companies resell these devices directly to consumers or businesses. Reusing smartphones extends their lifespan and reduces the need for new materials, lowering their environmental impact [6].

Refurbishment

Refurbishment involves restoring old smartphones to like-new condition. This process includes depollution, dismantling, deep cleaning, and repairs before the phone is put back on the market. Often, refurbishment is carried out in the same factories that originally produced the devices or They are sold to refurbishment and repair shops. Like recycling, refurbishment helps reduce the demand for raw materials and minimizes environmental harm [1].

Recycling

Recycling is the most complex process. It involves dismantling smartphones into separate components such as screens, batteries, casings, circuit boards, and other electronic parts [7]. Some older phones (and modern smartphone in lesser quantities) contain hazardous materials like arsenic, beryllium, antimony, cadmium, lead, mercury, and nickel, which must be carefully removed to prevent long-term health risks.

In an effort to reduce the environmental impact of smartphones, manufacturers are working to replace harmful materials with safer alternatives. For example, polyvinyl chloride (PVC) and phthalates have been substituted with thermoplastic elastomers, and brominated flame retardants (BFRs) are being replaced by metal hydroxides and phosphorus compounds. These changes make recycling easier and reduce toxic emissions when plastics are incinerated [8].

Once harmful substances are removed, the components are shredded, and valuable materials such as plastic, aluminum, cobalt, rare earth elements (REEs), glass, steel, and precious metals like gold and silver are recovered. These materials are then reintroduced into the supply chain, reducing the need for new raw materials and minimizing electronic waste.

By properly managing the end-of-life stage of smartphones, we can significantly reduce their environmental impact and promote a more sustainable electronics industry.

References

[1] Cornelis P. Baldé, Ruediger Kuehr, Tales Yamamoto, Rosie McDonald, Elena D’Angelo, Shahana Althaf, Garam Bel, Otmar Deubzer, Elena Fernandez-Cubillo, Vanessa Forti, Vanessa Gray, Sunil Herat, Shunichi Honda, Giulia Iattoni, Deepali S. Khetriwal, Vittoria Luda di Cortemiglia, Yuliya Lobuntsova, Innocent Nnorom, Noémie Pralat, Michelle Wagner, Global E-waste Monitor 2024. International Telecommunication Union (ITU) and United Nations Institute for Training and Research (UNITAR), Geneva/Bonn, November 2024. (accessed February 7, 2025)

[2] N. Lövehagen, J. Malmodin, P. Bergmark, S. Matinfar, Assessing embodied carbon emissions of communication user devices by combining approaches, Renewable and Sustainable Energy Reviews 2023. https://doi.org/10.1016/j.rser.2023.113422

[3] Nathalie Bödtker-Lund, In the wake of plastic pollution, the era of pauperization begins, PulPac 2024, Sweden. (accessed February 7, 2025)

[4] Suzanne Greene, Freight Transportation, MIT Sustainable Supply Chains Initiative, USA, 2023. (accessed February 7, 2025)

[5] NSYS Group Team, Average Device Lifespan: How LONG Does a Cell Phone Last?, NSYS 2024. (accessed February 7, 2025)

[6] Environmental Protection Agency (EPA), Basic Information about Electronic Stewardship, Environmental Protection Agency, USA. (accessed February 7, 2025)

[7] Enviropass, Recycling Electronic Equipment- How does it work?, (accessed February 7, 2025)

[8] Apple, 2024 Environmental Progress Report, 2024. (accessed February 7, 2025)