E-waste isn't the only problem associated with smartphone manufacturing.
While the energy required to power our devices remains significant, for devices like smartphones, tablets, and PCs, the largest share of greenhouse gas emissions now comes from the manufacturing phase. Devices have become more energy-efficient due in part to the shift to mobile platforms, as well as more complex, which increases the amount of energy required to produce each one. Life-cycle assessments of smartphones, tablets and PCs have consistently found that the production phase, including resource extraction and processing, component manufacturing, and assembly, contributes the most to total greenhouse gas emissions, in some cases as much as 80%.
Smartphones and other electronic devices are among the most resource intensive by weight on the planet–miners must dig through more than 30 kilos of rock to obtain the 100 or so grams of minerals used in a smartphone. Industrial mining scars the Earth permanently, leaving behind toxic wastewater and soil, and rehabilitation of mining areas is uncommon.