E-waste, Pollution, and a Sense of Scale

Usually when e-waste is discussed, the story defaults to a post-consumer view of the problem: e-waste is what happens when people (consumers) throwaway their devices. Of course, post-consumer discarding happens but this is actually the smallest part of the overall waste arising from electronics. Much more waste, by far, happens in electronics manufacturing long before consumers even purchase their devices. What can we learn about electronic discards in the form of pollution from manufacturing and a sense of scale?

There are public sources of data that can help answer this question. The three NAFTA countries — Canada, Mexico, the US — each maintain pollution release and transfer registries (PRTRs). The European Union (EU) maintains a similar database. All of these databases publish information about the releases and transfers of pollution at the level of individual facilities across many sectors of the economy, including computing and other electronics manufacturers.

A very brief geohistory of PRTRs

The first PRTR database was established in the United States under a 1986 law called the Emergency Planning and Community Right-to-Know Act (EPCRA). The name of the law marks out an ethical conviction that people are entitled to know about the chemicals being released into the environment where they live by industrial facilities located nearby. EPCRA was partly a response to the Union Carbide disaster in Bhopal, India but also to at least a decade of grassroots environmental activism in the US (Bullard, 1994; Gibbs, 2010).

EPCRA created the Toxic Release Inventory (TRI), a publicly available database of chemical releases from industrial facilities. TRI is a mandatory reporting program that covers three broad classes of chemicals:

  • those known to cause cancer or other chronic diseases in humans
  • those that cause acute harms to human health
  • those that cause significant adverse environmental effects


PRTRs similar to the US TRI came about in Canada, Mexico, and the European Union in the early- to mid-1990s. Currently, some 44 other countries around the world operate PRTRs.

PRTR data and the electronics sector

The map below plots the magnitude and type of chemical releases at the facility level for the computer and electronic manufacturing sector in the US (click here for a live version of the map). One of the things the map shows us is that pollution from this sector is ubiquitously albeit unevenly distributed across the US. We may associate the ‘tech’ industry with Silicon Valley, but the facilities involved in the manufacture of computers and electronics products are located all over the US (Silicon Valley does show up on the map below. Here are two live maps I created about the region: Chemical Releases in Silicon Valley and Productionscapes).

Chemical releases from the computer and electronics sector, 1991-2015. Click here for live map.

There is also a more subtle lesson in the map above. The map deliberately violates a cartographic convention about how to use colour to depict information. Conventionally, there should be only so many colours as there are data categories. Yet, when it comes to toxicant chemical releases from the computer and electronics sector, there are so many chemicals in use that there are not enough distinct colours to match.

Chemical releases from the industry overflow our ability to fully know them in the sense of cartographic convention. They spill beyond knowability in several other ways as well, as the images below suggest.

Number of toxicants tracked in various PRTR systems. Circles are proportional to number of toxicants tracked.

PRTR data are available for all NAFTA countries and for the EU. NAFTA data are collated by the Commission for Environmental Cooperation (CEC). The image above shows the number of toxicants tracked in each of the three NAFTA countries individually, the CEC, and the EU. The size of circles are proportional to the number of toxicants tracked.

Among the NAFTA countries, the US actually tracks the largest number of chemical pollutants released by industries (695 chemicals). Mexico and Canada track many fewer such toxicants (398 and 324 respectively). Meanwhile, the EU tracks only 91 chemical pollutants. When the list of chemicals tracked by each jurisdiction are compared, however, only 10 are common to all. This means that the same industrial sector (e.g., computer and electronics manufacturing) will look very different from a pollutant releases perspective across these jurisdictions even if the same underlying industrial processes are in use or, indeed, even if the same company with facilities in multiple jurisdictions were examined.

Scaled comparison of number of chemicals tested and found toxic (yellow circle) compared to the number of chemicals tracked in PRTRs of NAFTA and EU (blue circle at tip of arrow). Circles are proportional to scale.

The problem of knowing pollution from PRTR data becomes more profound if you consider the difference in scale between the number of chemicals tracked by PRTRs and the number of chemicals tested and found toxic. Such testing is tracked in the Chemical Abstracting Service. In the image above, the large, yellow circle is proportional to the number of chemicals tested and found toxic while the blue arrow points to the tiny dot proportional to all chemicals tracked by the PRTRs of the CEC and EU. This means that even in the US, the jurisdiction that tracks the largest number of toxicants released by industry (695 chemicals), only some 0.36 percent of all chemicals tested and found toxic are even tracked. This leaves over 99.6 percent of toxic chemicals invisible to citizens, regulators, or other concerned groups.

The scale of unknowability becomes even more profound when comparing the total number of chemicals available for industrial uses to those tested and found toxic. The red circle in the image below is proportional to the number of industrial chemicals available for use as of August 2018. There were approximately 153,000,000 such chemicals. The blue arrow points to the dot representing all those chemicals tested and found toxic. This means only 0.12 percent of all chemicals available have even been tested for toxicity.

Scaled comparison of all chemicals available for industrial use as of August 2018 (red circle) versus all chemicals tested and found toxic (yellow circle at tip of arrow). Circles are proportional to scale.

Of course, the electronics manufacturing sector doesn’t necessarily use all the chemicals that have been tested and found to be toxic or all of those in the ever expanding group of synthetic chemicals becoming available for industrial applications. But it will use some of them. PRTR data show us that.

Our inability to fully know pollution released from the electronics manufacturing sector is made more tangible if we consider a concrete example. Apple Computers publishes a list of its top 200 hundred suppliers (Apple deserves credit for making this supplier list public). The list includes street addresses and this allows the locations of those suppliers to be mapped. Doing so gives us an important result: we see that Apple’s supply chain involves many national jurisdictions, only a select few of which operate PRTR systems (see map below).

Map of Apple’s top 200 suppliers (blue dots). Countries in which those suppliers locate and which have a PRTR system are show in green. Those countries where suppliers are located, but which have no PRTR system are shown in yellow.

The map above of Apple’s suppliers shows us several important things. Not surprisingly, Apple’s supply chain is globally but unevenly distributed. The firm has suppliers in Asia, Europe, North and South America. However, of its suppliers in Asia, a large number are in China and in various countries of South and Southeast Asia. Neither China nor any of the countries in the region currently operate a PRTR system (Japan and South Korea are exceptions). As a consequence, although we can know the location of some of Apple’s suppliers in these regions, we are currently unable to know what and how much pollution they release. Apple is, of course, just one major brand (albeit an important one). Other brands will have similarly globally but unevenly distributed supply chains with similar consequences in terms of being able to know — or not know — about pollutants released from their facilities.


One might argue that we need to fill in the massive gaps in knowledge about pollutant releases from manufacturing before we act to curb that industrial pollution. More knowledge in this regard would be better, but lobbying for more disclosure before acting is a disingenuous move. It supports the status quo while deferring regulatory and policy action into an ever receding future horizon. The status quo is about externalizing pollution and its costs from the manufacture of computers and electronics. Although we don’t know — indeed cannot know — enough to fulfill people’s and communities’ right to know about what and how much facilities near them are releasing, we do know enough to act. Relevant action will focus on changing what happens in manufacturing, before pollution becomes pollution. This could mean expanding the number of toxicants that industries are required to report. It could mean regulating out the use of certain chemicals. It could mean requiring manufacturers to internalize the costs of the pollutants they release. Other options, like other worldings, are possible.


Bullard, Robert D. Dumping in Dixie: Race, Class, and Environmental Quality. 2nd ed.. Boulder: Westview Press, 1994.

Gibbs, Lois Marie. Love Canal and the Birth of the Environmental Health Movement. Washington: Island Press, 2010.