Friday, December 4, 2009

The Environmental Impact

95 percent of electronic waste is recyclable. However, unregulated recycling can cause more harm to the environment than landfilling. While many companies, such as Apple, have safe and effective recycling programs, the majority of recycling companies export some percentage of their electronic waste to China or poor countries in Africa, where the waste is “recycled,” or destroyed and stripped of its valuable metals. Though this seems like a good thing on the surface, because components are being repurposed, unregulated recycling centers burn or dissolve the plastic components to release the precious metals: a process that releases environmental contaminants into the air, land, and water that would otherwise remain trapped and inert in landfills (Robinson 2009).

The most common type of electronic waste as of 2009 is cathode ray monitors (those big tvs with the curved screens that nobody uses anymore), which make up about 45 percent of the waste stream, but there is evidence that this is changing. We are increasingly seeing LCD products and other more advanced, technologies in the waste stream (Robinson 2009).

However, more advanced technologies tend to have new, advanced substances in them that are relatively unstudied. Platinum group metals, for example, are found in iphones and other modern hand-held devices, but little or nothing is known about their potential impact on health and the environment…except that they are getting into everything. Traces of platinum group metals, for example, have been detected in water, soil, and even snails around recycling centers in Africa. There is an exponential relationship between the growth in a country’s wealth and the number of computers per person.

Still, it is difficult to determine how the amount of e-waste will change in future years. There is currently a trend of miniaturization in the electronics industry: cell phones, cameras, and laptops are generally getting smaller. Also, computing is becoming more centralized. Cloud computing, or linking electronics into a centralized, stream-lined infrastructure, could lead to smaller amounts of e-waste as it requires less large-scale servers and other computing infrastructure components. Also, some new electronics are more recyclable and less hazardous, such as LCDs which contain much smaller quanitites of hazardous materials such as PCBs.

However, electronic lifetimes are getting shorter as companies scramble to lower prices and up profits. The average laptop is engineered to be obsolete after 2 to 3 years. Also, appliances and vehicles are becoming increasingly electronic. Many modern refrigerators and washing machines contain electronic components. This will also contribute to the e-waste stream, as appliances are not generally considered in calculations of e-waste quantities.

The average piece of e-waste is 43.7 percent metal, 23.3 percent plastic, 15 percent glass, and 17.3 percent electronics. The primary valuable components are copper, gold, and platinum group metals. The most abundant of these substances is copper. Out of the 20 million tons of e-waste generated every year, 820,000 tons of it is copper (Robinson 2009).

Printed circuit boards contain these precious metals in concentrations 10 times higher than which can be achieved through commercial mining, making it relatively practical source for these substances. To extract them, the plastics and other non-valuable components are either burned away or dissolved in acid. Both of these methods release toxins into the environment, many of which would NOT have been released had the electronic item decayed slowly in a landfill (Robinson 2009).

There are a number of substances found in electronic waste that are known to be hazardous to the environment. These include Lead, Antimony (Sb), Mercury (Hg), Cadmium (Cd), Nickel (Ni), Polybrominated diphenyl esters (PBDEs), and polychlorinated biphenyls (PCBs). When burned or dissolved in acid, this waste releases dioxins, furans, polycyclic aromatic hydrocarbons (PAHs), polyhalogenated aromatic hydrocarbons (PHAHs), and hydrogen chloride (Robinson 2009).


Lead is known to be extremely hazardous to humans and animals, and has detrimental effects on reproduction. Though lead is not known to have serious effects on the environment itself, it can accumulate in soil and water and, in that way, be transmitted to humans and other organisms. It can also be spread through biomagnification (Sepúlveda, 2010).


Antimony has toxic properties similar to that of arsenic. It is a component of polyethylene terephthalate (PET), a common type of plastic. Though it is safe for relatively short periods of time, it can eventually leech into water. This leeching occurs more quickly in more acidic environments, so if this plastic is dissolved with acid, as is a common practice in third world recycling centers, antimonly can easily enter the environment, causing serious illness and death in humans and other animals (Westerhoff 2007).


Mercury is found in many batteries and electronic devices, and is known to have serious health effects. As is well known, mercury can accumulate in the bodies of fish, and thereby be spread to all organisms that consume them, including humans. In addition, it has been observed that, in warm climates, the oxidation of mercury in the environment can be accelerated, leading to the creation of oxidized Hg atoms that are known to be associated with ozone depletion (MacDonald 2000).


Cadmium is another element that has been shown to have serious health effects. It is contained in many electronics, and can accumulate in soil, vegetation, and mollusks. Cadmium is present naturally in many vegetables and mollusks, but high concentrations due to contamination are very dangerous (Jarup 2009).


Nickel can have extremely detrimental effects on plant growth if it exists in high levels in soil. This toxicity increases with changes in soil Ph. However, there was fairly wide variation in toxicity between different types of soils, so more research is needed to assess the exact environmental effects and properties of nickel contamination (Rooney 2007). There is evidence that high levels of nickel can change the entire chemical composition of plant species. For example, St. John's Wort, a plant often used medicinally, fails to produce concentrations of the chemicals that lend it's healing properties if it is grown in high concentrations of nickel (Murch 2002).

Furans (polychlorinated dibenzo-furans, (PCDFs))

Not enough is known about the precise chemicals of furans to determine its exact environmental effects. However, studies show that it has dangerous potential for the environment in that it can promote the creation of aerosols and contribute to smog pollution. It could also be dangerous because of its ability to interact chemically with chlorine, which is often found in high concentrations on coastlines due to industrial emissions (Villanueva 2007). Furans can be carried long distances through the atmosphere, and generally accumulate at the poles. However, little is known about their effects on the environment or on global warming (Lohmann 1998)

Polycyclic aromatic hydrocarbons (PAHs) and Polyhalogenated aromatic hydrocarbons (PHAHs)

PAHs and PHAHs are released when e-waste is burned. These substances are lipophylic, and therefore accumulate in the foodchain. They have been shown to have serious health effects, including genetic damage and have been detected in foods. More research is needed to assess the impact of these substances on the environment. (ASTDR 2009)

Hydrogen Chloride

Hydrogen chloride is known to be toxic to humans. However, it can also have serious environmental effects. It dissociates in water and soil, and can cause the Ph of both to become more acidic, damaging crops and entire ecosystems. It is not, however, accumulate in plants or animals (ATSDR 2002).

Environmental effects:

PBDEs, PCBs, and PCDD/Fs do not exist naturally in the environment. Unusually high concentrations of all of these substances can be found in processing centers in developing countries as well as in the farm lands, organisms, and water in the areas surrounding them.

Polybrominated dephenyl esters (PBDEs), which are used as flame retardants, are mixed into plastic components. If the plastic is left to degrade in a landfill, PBDEs will not be released into the environment (at least not for hundreds or thousands of years). However, when plastics containing PBDEs are burned these harmful substances are released into the environment. Because they are lipophilic, (meaning they stick to lipids, or animal fats) they can accumulate in organisms, both plants and animals, and be spread throughout the food chain in a process called biomagnification. They have been shown to interfere with the immune, endocrine, and reproductive systems of all types of animals. Though these effects have never been directly observed in humans, there is likely to be an effect. (de Witt 2002)

Dioxins, primarily Polychlorinated dibenzo-p-dioxins, are released into the environment when plastic wires are burned to recover copper. The effects they produce are similar to those of PBDEs. They are not found in water, as they are hydrophobic, but they have been detected in certain aquatic plants. Though no effect has been observed on the health or growth of the plant itself, these plants are consumed by fish and mammals, who are very sensitive to dioxins. Also, it is possible that the effects of dioxins take a long time to be expressed, and it is simply to early to tell what effect they might have. In addition, dioxins can travel long distances because they are able to bind to aerosols: small particles of matter in the air. This means that they can easily be carried outside the range of recycling centers, and through ingestion and subsequent biomagnification, affect ecosystems and foodchains far from the actual site of contamination. Dioxins can also accumulate in sediment or on the surface of bodies of water. Accumulation represents a kind of sequestration, but it is possible that these captured molecules could reenter the ecosystem. Similarly, dioxins in the soil tend to remain non-volatile, but factors such as erosion and changes in soil characteristics could make them become active again (Wenning 2008). More research is needed to define their potential impact on ecosystems. Very few studies assess the impact of dioxins on plant life or soil.

Polychlorinated biphenyls (PCBs) are used as coolants and insulators for transformers and capacitors. They were banned by congress in 1976, but are still found in high concentrations in electronic waste. They are known to cause disfiguring dermatitis at high concentrations and are believed to be carcinogenic. In 1976, all fishing was banned in the Upper Hudson river due to contamination from two upstream manufacturing plants.

Platinum Group Metals

These metals have become common in electronics relatively recently due to their high stability and chemical resistance. However, these elements are known to accumulate in the environment. PGMs initially accumulate in particulate mater on the ground, in the air, and in water, and from there get incorporated into organisms. They seem to accumulate in the highest levels in water and in vegetation. More research is needed to determine what effect this accumulation can have on the environment (Ravindra 2004).


Above all, more research is needed to determine the exact environmental effects of each of these contaminants. There is already significant documentation and quantification of the presence of these contaminants at all levels of ecosystems: from soil and water to humans. We know that these substances are already out in the world. They are continuing to spread through biomagnification and, due to their lengthy lifetimes, they aren’t going away. However, there is little thorough and conclusive research on the specific impacts of each of these substances on the environment. We need to know what they are doing to ecosystems, how much of each substance elicits how much of an effect, how long it will take for us to start seeing serious break downs in lifecycles of plants and animals, and how soon these contaminants will become a serious concern for human life around the world, rather than only among third-world electronics recyclers.

Electronic waste is gaining attention from scientists and policy makers around the world, and there are several interesting efforts underway to gather more data on current conditions and develop solutions. One such project comes from Carlo Ratti of MIT’s SENSEable City lab. He and his team have developed small electronic tracking devices that, unlike GPS or RFID tagging systems, allow objects to be tracked anywhere around the world, even if the object is buried (RFID tags can only be read with sensors, and GPS systems require a direct line of sight between the sensor and a satellite). Ratti’s tags are able to triangulate an object’s location using the signals from cell phone towers, which are found all over the world, even in the poorest of countries. The tags can be affixed to different pieces of waste and then tracked in real-time for long periods of time. This data will throw light on waste removal systems, allowing us to determine exactly where waste is going and how it gets there. Though the SENSEable Lab’s current goal is to assess the state of waste in two U.S. cities, Seattle and NYC, in order to find inefficiencies in urban waste management systems, the technology could potentially be applied to studies of electronic waste. The electronic waste trade is clandestine, and by tagging electronics with these discrete devices, we could assess which companies are sending their electronic waste overseas for “recycling.” This information would allow for tighter regulation and, hopefully, an end to the trade in harmful electronic waste.