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| Fig. 1: Primitive e-waste sorting in Agbogloshie, Accra, Ghana (Source: Wikimedia Commons) |
Electronic waste, or e-waste, is an umbrella term encompassing all electronic devices that have reached end-of-life and are disposed of through donation, recycling, or regular waste streams. The United States Environmental Protection Agency (EPA) defines e-waste as a subset of used electronics comprising materials with reusable or recyclable value that, when properly treated, can reduce the effective waste dumped into landfills in the US and abroad. [1] The high costs of domestic e-waste disposal in developed countries has pushed a significant but unquantified proportion of e-waste recycling streams to developing countries such as China, India, and Africa. [2] For instance, a study of e-waste disposal in Italy commissioned by the EPA found that while it cost $64,000 USD to process and dispose a container of 15,000 tonnes of e-waste legally in Italy, it only cost $5,000 USD - more than ten times less - to ship and dispose of the same amount of e-waste illegally to countries in Asia. [3] The final destination of as much as 80% of global e-waste cannot be traced and is likely dumped in landfills or illegally traded to developing countries for recycling. [4] Exacerbated by the increasingly early obsolescence of electronic products - in just 5 years from 2000 to 2005, the average lifespan of a personal computer decreased from 4.5 years to 2 years - and our ever-growing consumer market that pushes out newer, faster, and shinier electronic gadgets every year, the global e-waste footprint is projected to double every 16 years and has already grown from 33.8 million tonnes in 2010 to 53.6 million tonnes in 2019. [5,6]
When we think of recycling electronics, our minds naturally jump to the "high value" electronics, such as cell phones, laptops, and computers. For these high value electronics, e-waste recycling is a profitable business. Since precious metals in e-waste are more abundant than those mined in ores - between 0.5-15 ppm of gold can be extracted from gold ores, compared to 10,000 ppm in central processing units (CPUs) - leaching metals from high-value electronics can actually decrease energy consumption and pollutant emissions compared to extraction processes using natural minerals. [7] As a case study, let us examine the estimated number of obsolete computers in the US in 2020, which is projected to be 100 million units. [8] Assuming an average of 10,000 ppm (by weight) of gold in each computer CPU and an average CPU mass of 45 g, this gives us the following potential gold recovery [7,8]:
| 1.0 × 108 CPU × 0.045 kg CPU-1 × 10000 × 10-6 | |
| = | 4.5 × 104 kg gold recoverable |
For the primary production of 1 kg of gold in Germany, the energy demand is 240 GJ and the associated carbon emission is 16 tons of CO2. This compares with 8 GJ and 1 ton of CO2 associated with 1 kg of recovered gold from e-waste. [9] Given our estimate of the recoverable gold from obsolete US computers and assuming a similar domestic energy and carbon cost to e-waste gold extraction, this is the equivalent of approximately 1.04 × 1016 Joules of energy consumption reduction and 7.4 × 105 tons of carbon emission reduction vis-a-vis primary gold production.
On the other hand, the situation with "low value" electronics, such as lamps and microwaves, is less than ideal. The good news is that most electronics, regardless of their value, can be recycled; the bad news is that it is not always in the recycling companies' financial interest to do so. [10] For "low value" electronics that have neither precious metal components nor a high resale value, the overhead costs of recycling facilities are often too high to be considered profitable, and the more economical, if less environmental, option is to dispose of these low-value e-waste parts in sanitary landfills. [10] For the low-value sector of e-waste consisting of mixed plastics, chemicals, and metals to actually be recycled properly will likely require both government subsidization and enforced legislation. [2]
The Extended Producer Responsibility (EPR) is a concept that relies on electronics companies to shoulder the environmental responsibility of recycling post-consumer products. The Waste Electrical and Electronic Equipment (WEEE) is a electronic waste management program and recycling policy that many countries follow. In Taiwan, where recycling is backed by financial incentives from the government, the EPR concept plays out as a tax system, in which producers and importers of electronics are required to pay recycling fees based on their sales and recycling rates. Taking into account factors such as the cost of collection and treatment, the number of obsolete units of an electronic device, and other administration costs, the following equation breaks down the recycling fee imposed on Taiwanese tech companies under the EPR system: [11]
| R | = | W (C α +
E1 α1 +
E2 α2) +
L - F S |
where R is the recycling fee US$ per unit, C is the collection and treatment cost per unit US $ per unit, α is the target collection fraction, α1 is the fraction of waste properly disposed that is not recycled, α2 is the fraction of waste products littered but not properly disposed of, E1 is the averaged environmental cost of unrecycled but properly disposed products (e.g. sanitary landfill or incineration) in US $ per unit), E2 is the averaged environmental cost of littering for unrecycled and improperly disposed products in US $ per unit, W is the estimated obsolete amount (No. of units), F is the fund balance amortization ($), L is the administration cost of recycling ($), and S is the forecast of annual new sales (No. of units). [11]
As we can see from the equation above, if the ratio W/S is small (many new sales compared to obsolete units), even if the ratio of wasted products (recycled or improperly disposed) is high, the recycling fee does not rise substantially, which may not disincentivize companies from rapidly pushing out new, profitable electronics products and paying the recycling fee. Not to mention, most of the developed countries that are the primary producers of e-waste do not have this kind of regulatory system in place.
Perhaps the most notorious aspect of e-waste streams is the health risk associated with improper disposal and recovery. In a 2005 sample of 154 children in Guiyu, China, where over 60% of families are tied to the e-waste recycling business, alarming levels of toxic heavy metals such as lead and cadmium were detected in the bloodstreams of the children. [12] More than 70% of Guiyu children had blood lead levels (BLLs) greater than 10 µg/dL and over 20% had blood cadmium levels (BCLs) greater than 2 µg/dL compared to only 39% and 7%, respectively, of children in Chendian, a neighboring town in which clothing manufacturing, rather than e-waste processing, is the leading industry. [12] Blood lead levels averaged 15.30 µg/dL among residents of Guiyu as a whole while the BLL among residents in China as a whole averaged to approximately 8 µg/dL - almost half the amount. [13] While heavy metal exposure is known to cause a myriad of adverse health effects in children, including lower birth weight, reduced lung function, hyperactivity disorder, and DNA/chromosome disorder, adults are equally at risk. [14] Heavy metal exposure in adults has been linked to increase risks of cancer and other pathological diseases. [15] In a study of e-waste recycling workers in Accra, Ghana, urine samples collected from the workers showed signs of iron, antimony, and lead contamination. [16] Furthermore, in many of these primitive e-waste recycling sites, workers sort through metals and plastics without gloves or other protective equipment, as shown in Fig. 1, leading to direct skin contact and exposure to toxic materials.
Despite being one of the largest exporters of e-waste, the United States is the only developed country that has not ratified the Basel Convention on hazardous waste, which controls the international trade of hazardous wastes and requires "notice and consent" to countries importing e-waste. [17] To make matters worse, in a survey conducted across 19 universities in the US that included faculty, staff, and undergraduate and graduate students, only 18-20% of students were aware of proper e-waste disposal options, compared to 40% of faculty and staff, and very few participants were aware that low-value electronics, such as lamps and air conditioners, also constituted e-waste. [18] These trends contrast sharply with the recycling guidelines and adherence in East Asian countries like Japan, where stricter governmental regulation of waste streams, through legislations such as The Law of Promotion of Effective Utilization of Resources, establishes a recycling-based economic system promoting the collection, reuse, and reduction of waste by businesses. [19] This system in turn allows for consumers to receive and use "appliance recycling tickets" to arrange for waste appliances to be directly collected and processed. [19] For the US, on top of the lack of legislative guidelines and financial incentives for Americans to properly dispose of electronics, adherence is even more difficult when the public is not aware of what constitutes e-waste. This poses the troubling question of whether the US government has a moral duty to do more in educating the American public and regulating its domestic and international e-waste streams in a more transparent manner.
At the end of the day, however, the answer to the growing global e-waste problem lies beyond simply leaching precious metals for repurposing. The "dirty" truth is that many electronics recyclers that claim to seek a "zero landfill" goal do not recycle the waste they collect whatsoever and instead sell them to junkyards in developing nations, as it is cheaper to export the waste than to recycle it. That is to say, even if all consumers in developed nations adhered to e-waste disposal guidelines perfectly, much of the global e-waste streams would still be illegally exported to developing countries and improperly handled. Reusing and reducing electronic products, either by purchasing refurbished or secondhand products or skipping out on that tempting new iPhone upgrade, are far more effective measures for reducing global e-waste traffic - by reducing demand. But perhaps this is at odds with the very core of our capitalist world.
© Elaine Lui. The author warrants that the work is the author's own and that Stanford University provided no input other than typesetting and referencing guidelines. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
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