HUMAN PRACTICES
Initial Project Application (Mining)
Tailings ponds hold a sort of twisted beauty. As visually pleasing as they may be, seeing a pond running red and brown begs the question of why. Upon further inspection, the beauty gains its aforementioned twist; that red water is composed of chemical byproducts, ores, and sediments, among other substances. While the beauty of these toxic waters led to an initial attraction, the problem they posed was what ultimately forged a relationship between this year’s Waterloo iGEM team and the idea of treating effluent. The fact that the formation of what is essentially a chemical soup is a normal practice of the Canadian mining industry planted the seed for an idea that developed into much more.
This chemical soup is called mining effluent, and it is defined as any type of deleterious substance that is made as a result of mining operations.2 Mining effluent can contain dangerous substances such as arsenic, lead and cyanide, as well as copper, nickel and zinc.2 Initially, helping purify and remediate these toxic ponds using a bioreactor seemed like a promising goal to work towards. Mining in Ontario is not as heavily regulated as one would hope, so our team saw an opportunity to resolve a problem that would have implications all the way up to the provincial government. Upon discussing with different government employees from the mining sector as well as with Mr. Brian Montgomery, we realised that metal recovery would be the best way that our idea could fill a hole in the mining industry. However, the focus on metal recovery ended up shifting our project direction to a whole new industry, for a variety of reasons.
The biochemistry of our proposed system to recover metals is quite complicated, requiring very specific conditions to ensure both the survival of the metal-binding proteins and that the metal being recovered is in a state that allows it to be recovered. The initial idea of recovering iron from the effluent was discarded due to the complexity of the equilibrium between iron ions in different oxidation states when it is dissolved in water. While Fe2+ is water soluble, but Fe3+ tends to form solid Fe(OH)3.1 Because the effluent flowing through the column would contain iron in both of these forms, the presence of the solid Fe(OH)3 would end up clogging the system. Despite this setback to the initial plan, Mr. Montgomery’s insight brought our attention to other metals, namely cobalt, nickel and copper. Our research into cobalt-binding proteins, nickel-binding proteins as well as how cobalt and nickel are typically found in effluent waters (e.g. cobalt is often being found in sediments, while nickel often binds to other substances and forms compounds such as nickel sulphate), led the project away from recovering these metals as they would not be compatible with the bioreactor that had been designed.3,4 Conversely, due to the abundant literature on copper-binding proteins and copper’s prevalence in multiple types of wastewaters, using a bioreactor to recover copper proved to be a very feasible idea.5,6
While our decision to shift to copper ensured that REMINE would be a functional bioreactor, it exposed a gap in the implementation of the project. As Mr. Montgomery pointed out, copper was not the most sought after metal for recovery processes in the mining industry, nor was it a large component of most mining effluent. While this may have initially seemed like a roadblock, the shift away from mining ended up paving the way to greener pastures as REMINE settled in nicely within wastewater treatment in the electronics manufacturing industry.
Finding a New Application (Electronics)
Once the project direction shifted towards metal recovery, the electronics manufacturing industry seemed like a natural fit for REMINE. Due to the industry’s diversity, to simply say that REMINE was a ‘good fit’ for electronics manufacturing was not good enough. What started out as an answer to our implementation issue quickly gave way to more questions: what type of electronics would REMINE be best suited for, and where along the manufacturing process could REMINE best be implemented? For this decision to be finalized, a variety of different avenues were explored and assessed.
Initially, electronic waste recycling seemed like a promising area to focus on. Recycling copper is up to 85% more energy efficient than producing it from primary ores.7 This was an encouraging statistic, but upon further inspection, REMINE did not prove to be compatible with this type of process. Currently, most electronics recycling methods utilize hydrometallurgical processes which primarily aim to precipitate solid copper from wastewater to form a sludge, during the recovery process.7,8 This posed a major challenge, as having copper ions in solution is critical to the proper functioning of the REMINE column. Furthermore, electronic waste recycling is predominantly composed of physical waste which is not suited for our system.
Electronic waste recycling was not the only idea discarded due to solubility issues, electroplating faced the same unfortunate outcome. Initially, this process seemed like a good fit for REMINE’s implementation, due to the fact that plating typically includes copper, among other metals.9 However, the process of recovering copper from electroplated objects involves precipitation, coagulation, flocculation and sedimentation.9,10 On the flip side, the recycling industry presented an interesting case of business ethics that our team further analyzed through independent research and stakeholder consultation. Furthermore, communicating with stakeholders from Aevitas Hazardous Waste Management confirmed that precipitation was an industry standard as a way of allowing the safe disposal of the metals in solution. Conversely, REMINE aims to replace precipitation steps altogether, by recovering the copper present in the solution. Electrowinning and electrorefining were also discarded due to the use of electrolysis as an industry standard.11,12 The electrolysis process is cheap, efficient and leads to solid deposits of pure copper, so REMINE was once again left without holes to fill.
While investigating electroplating, another issue arose: pH level. Many metal recovery processes use a specific pH as part of the precipitation procedure and often lower it to very acidic levels.9,10 For example, in the case of electroplating, prior to precipitating the desired metal(s), the pH is often around 3.5.9 Even if REMINE had no involvement in the precipitation process, another challenge to overcome was going to be finding a process involving a pH at which the proteins could function.
Despite the setbacks endured, the beauty of the electronics manufacturing industry is that, above all else, it is diverse. After countless hours researching, a feasible option was finally found.
Metal finishing is a process similar to electroplating, where the surface of an object is altered to improve durability and appearance.13 The process of metal finishing generates wastewater, and the current procedures for managing this wastewater are not very efficient.14 Part of the inefficiency of this process is the drag caused by the wastewater having to travel through different tanks before it has been fully processed.15 Current metal finishing procedures require wastewater to travel through multiple pH altering tanks, in order to precipitate the metals out of solution.15 However, having wastewater with dissolved copper ions in solution is exactly what REMINE needs. REMINE could easily fit into the metal finishing wastewater treatment process by being inserted after the first pH adjustment tank. This tank could be used to make the pH suitable for the proteins in the column and then the protein-friendly wastewater could be pumped through REMINE, allowing for copper to be recovered and reused, instead of undergoing further downstream wastewater treatment processes. After the copper is recovered, the wastewater could continue through the normal treatment process and be safely discarded.
While the path to metal finishing was rocky, gaining insight into different areas of the electronics manufacturing industry, even those that were not compatible with REMINE, allowed us to find an area to implement our project that has real benefits for the industry, financial feasibility and that would be compatible with a bioreactor such as REMINE.
Why Recovery and Not Simply Removal?
When implementing a novel synthetic biology product, there are countless hurdles that must be addressed to get the proposed solution from our lab into its practical application. In general, a significant knowledge gap exists between those creating the solutions and the stakeholders expected to use and engage with it. Processes and design work can be explained, but factors such as cost, efficiency and accessibility are aspects that can speak to the industries and individuals involved in product use and success.
In the development of REMINE, it was crucial to analyze our final product in every step of the way, from a stakeholders’ perspective. Diverse discussions with industry representatives as well as our own critical thinking helped guide the thorough development of our product. Early discussions with Brian Montgomery in particular, a mining regulations lawyer, helped focus the scope of our project in a number of ways to optimize the feasibility of our project, specifically through elements that would increase its value in the eyes of stakeholders.
One perspective monitored by our members investigating economic considerations was the cost-effectiveness of REMINE. With exact specifications of the product’s scalability, as well as the inability to account for labour and maintenance costs, it would not prove effective to perform an exact quantitative financial analysis of our method of electronic wastewater purification compared to current methods.
Instead, a qualitative approach was taken where we analyzed the specific features of our system compared to current methods. This led us to realize what features would significantly impact the cost of our system and make it more desirable than the current industrial solutions.
After analyzing current filtration methods, it was evident that our goal was to be able to release treated electronic manufacturing wastewater into the environment after metal extraction. However, these methods did not explain how the remaining ionic residue was handled after its recovery. The giant question mark left by current methods prompted us to find an answer; not just to prove our system as superior, but to consider approaches possibly not yet implemented by the electronics industry as a whole.
Brian Montgomery aided us in recognizing the value of the metals left in our column; their disposal may come at a greater cost than their own value. He mentioned that there are no current effective methods of recovering the filtered metals, and if it could theoretically be recovered and sold for profit, REMINE would hold its place as a never-before seen innovation.
Copper, in particular, is incredibly valuable to the electronics industry. 61% percent of all copper mined is turned into some sort of electric conductor.16 This prompted our process design to account for recoverability; if we can recover the metal ions filtered out of the wastewater, we will possess an asset that can be re-sold to those in the metals market. Copper has extensive physical properties as a conductor, and as a result, its high demand in the electronic industry is not going away any time soon.
Being able to design the product around that granted it an element of cost-effectiveness unlike the other waste treatment methods currently in place. With the ability to recover and resell copper filtered out of the wastewater at $4.82/kg, REMINE will end up paying for itself.17
A zero-cost approach to environmental accountability is a much more attractive phrase to stakeholders that highlights the pure practicality of the product. It would cost approximately $1.92 USD in operating costs per pound of copper mined to continue to obtain copper from mining alone, as well as the crucial environmental considerations.18 After establishing its role in the industry, REMINE can continue to develop with the sound support of key stakeholders.
Environmental and Health Impacts
With the growing concern for environmental damage caused by heavy metal pollution from electronics manufacturing, REMINE seeks to address this nationwide issue. From an electronic product’s conception to its eventual discard, by-products such as chromium, nickel, and copper are released into local ecosystems19, which often results in irreversible damage. REMINE aims to remove and recover copper, a metal that poses significant risk to aquatic life and human health at high concentrations.20
Similar to other pollutants, copper’s significant impact is due to its tendency to bioaccumulate.21 In its particulate or ionic form, copper travels easily through the water system, leaching into surrounding soils.21 “In plants, elevated copper exposure causes reduced growth, photosynthesis, respiration and nitrogen fixation”.20 As a result, autotrophic diversity is reported to be visibly diminished in regions of high ground copper concentration.21
Further along the food chain, where metal concentrations grow significantly from prey to predator, the amount consumed by other organisms greatly exceeds the recommended intake.22 In a toxicity study on the cumulative effect of copper in aquatic organisms, food consumption, embryonic development, and overall growth were found to be diminished.22 Furthermore, when above the 100 μg/L threshold, the pond snail species Lymnaea luteola were observed to stop feeding completely as well as total inhibition of egg development.22 This effect may be attributed to the denaturation of certain proteins necessary for homeostasis, along with various other responses to overwhelming concentrations of heavy metal within the cell.20,24
When approaching the impact of copper accumulation in the human body (through drinking water, primarily, as well as plant and animal consumption), it is essential to consider the adverse effects on health and well-being.21 In Canada, drinking water ideally has ≤ 1mg/L of copper, however the Maximum Acceptable Concentration (MAC) is 2mg/L.25 This limit is proposed to avoid severe short and long-term bodily harm and illness, such as gastrointestinal distress, liver cirrhosis, kidney damage, and anemia.25,26 The impacts of copper on human life are widespread, even going so far as to have a disproportionate impact on those living in countries or communities of lower socioeconomic status due to ‘informal’ processing, where material is exported to areas “lacking adequate infrastructure for safe dismantling of waste goods”.27
As detailed above, there are multidimensional contributing factors of copper pollution, resulting in a cumulative negative impact. An aspect of key importance to Human Practices is the consideration of economic and social incentives for REMINE, and its integration to the overall implementation of our project. By investigating the diverse range of harmful impacts on aquatic biota, health, and ethical treatment of waste, we seek to address the urgent matter at hand with the proposed solution.
Policies and Regulations
To elucidate legislative procedures that the implementation of REMINE faces, it is important to consider the national approach to e-waste, as it reflects many obstacles in iGEM Waterloo’s problem space. Through our research, we came across the conception and application of Canada-Wide Extended Producer Responsibility, which represents the complete life cycle of integrated human practices. What follows is an overview of this executable, the full text of which can be found in our references:
Given the rapidly developing landscape of modern technology and ensuing economic exploitations, we willingly turn a blind eye to the ugly truth behind its damaging impact. The individual consumer in developed nations enjoys the convenience that metal-plated electronics bring on the daily, while the vague task of waste processing is left to facilitating agencies. Up until a decade ago, the majority of such protocols were referred to as Product Stewardship in Canada, which translated to regionally specific programs funded by taxpayers and/or environmentally allocated funds.28
Recognizing the continuous efficacy disparity between national efforts and our G8 nation counterparts, particularly in the treatment of solid waste, the Canadian Council of Ministers of the Environment drafted the Canada-Wide Action Plan for Extended Producer Responsibility (CAP-EPR), a jurisdictional program which aimed to shift the economically draining process of treating products at their end of life stage upstream.29 This is an initiative that many now recognize as one of Canada’s greatest environmental success stories. In the following text, a thorough examination will be conducted pertaining to the mechanism behind its successful implementation, how such regulations impact Waterloo iGEM’s targeted problem space of e-waste, and challenges/next steps for Canada as a nation.
As formally defined within the document, EPR is “an environmental policy approach in which a producer’s responsibility for a product is extended to the post-consumer stage of its life cycle”. With a two-phased approach, where Phase 1 sought to establish working protocols for major sources of pollutants including electronics and electrical products, the targeted deadline was set to be in 6 years. Starting with a quantitative outline of Canada’s waste diversion stats at the time, Figure 1 comprehensively reports waste production, disposal, and diversion in each province/territory.
To highlight areas of regional interest, Ontario’s diversion rate falls short of the already low national average of 22%. The detrimental impact of this continuous pattern is evident from an environmental aspect—landfill overflow, pollution, ecosystem degradation, etc. However, the other incentive taken into consideration is the economic opportunity of recovery, especially from precious metals found in e-waste:
Achieving a disposal rate of 500 kg/capita by 2030, however, would inject about $10 billion directly into the Canadian economy by increasing the recovery of paper, metals and plastics.29
As another benchmark, it is important to note that initially, four provinces had some form of EPR, specific to electronics.29
Over the next couple of years, a structured approach to implementation swept the nation. A combination of strategies such as policy and regulation amendments, cost breakdowns, and stakeholder analysis proved to be crucial to municipal and manufacturing co-operation, partnerships that often present major strife in most environmental actions. Such areas are of high interest to the Waterloo iGEM Human Practices subteam, as it embodies a full scale application of targeted principles. As described in the 2014 progress report, the creation of the non-profit Electronic Products Recycling Association (EPRA) was an essential component in bridging the chasm between industry and regulatory decrees. By centralizing the united goal through an established channel of communication, manufacturers were supported directly in the adoption of regional specifications. In certain regions, industry leaders have initiated voluntary electronic waste diversion programs, whose operations are independent from government mandates. Overall, eight provinces have fully adopted complete producer responsibility for electronic products at their end of life. The net quantifiable impact from the initial starting numbers is as follows:
While total waste disposed of has increased by about 8% over the past decade, the per capita amount of waste disposed of in Canada has decreased by about 2%. Diversion highlights from Statistics Canada show that from 2000-2010 the total amount of waste diverted to recycling or organic waste processing facilities increased by 33%.30
It is also noted that there are signs of positive environmental impacts over the five years, which goes beyond decreasing landfill occupancy.30
In essence, the conception and implementation of EPR programs in Canada encapsulate human practices on a nationwide level. Upon the identification of a notable problem, regulations, economic considerations and feasibility were accounted for through the comprehensively drafted action plan. For Waterloo iGEM as a team with multi-dimensional considerations, understanding the complete process of even one regulatory action plan is essential for real-world applications. Through CAP-EPR, current struggles we see in legislative documents with harmonization and community outreach realized on a national level, which indicates a potential for improvement beyond Waterloo iGEM. By acting on identified problems, Canada sends a seemingly small yet significant message to the international electronic industry. Mandating corporate producers of waste to take full responsibility through a co-operative approach is essential for the eventual paradigm shift on environmental accountability:
This provides incentives to producers and importers to design their products with less environmental risk, reduced use of toxic and hazardous substances, enhanced ease of product disassembly and with other factors reducing their products’ overall environmental footprint.29
As noted by the final update of September 2017, this ‘design-for-the-environment’ is yet to be realized, which remains to be a common theme in all large-scale manufacturing.31
Economic Impact
When analyzing the profitability of copper production, the value has remained relatively static over the past ten years. The value of Ontario’s production of copper was $1.4 billion in 2006 and $1.3 billion in 2015.32 Ontario mining companies use scaling (relative change of copper production per year) in order to understand how production will change in the future with the average expected change. Economically, the extraction of metals creates value by providing jobs, infrastructure development, government tax revenue, and leverages Ontario’s competitive advantages for international trade.32 The REMINE project creates another sector of metal extraction for profit. As a cyclical industry, selling prices are dependent on world markets while federal and provincial corporate tax payments vary greatly annually. The impact is beyond mineral extraction and processing. Metal recovery is linked to many other industries and sectors in the economy, including transportation, construction, equipment manufacturing, environmental management, geological services, education and research. This is key to considering the diverse fields of innovation that REMINE takes from. It will not only play its environmental role, but it significantly contributes economically in the collection of metals, integration into infrastructure, and financially optimizing the wastewater management process in a completely new way.
Business and Ethics
While examining electronics recycling as a potential implementation pathway, we came across rather interesting business practices. Electronics waste (e-waste) is often outsourced to developing countries for very low processing and maintenance costs due to the lack of regulated business practices: “material is exported to countries lacking adequate infrastructure for safe dismantling of waste goods”.27 The informal recycling practices can include men, women and children aiming to “recover valuable materials by burning devices to melt away non-valuable materials, using mercury and acids to recover gold, and dismantling devices by hand to reclaim materials of other value”.33
However, the problem lies in the treatment of workers. “Usually they do not wear protective equipment and lack any awareness that they are handling dangerous materials”.33 The lack of personal protective equipment when directly treating hazardous e-waste is linked to a myriad of health problems including: spontaneous abortions, stillbirths, congential malformations, abnormal thyroid function, and more.33
We had the opportunity to speak with a stakeholder within electronics recycling, Rolando Velasquez, from Call2Recycle. In our conversation, we asked about the factors relating to the increased desire for unethical outsourcing, aside from the financial incentive. The two main factors Rolando mentioned are traceability and consumerism. Traceability is the process of tracing a product's life cycle, from production to waste. New legislation in Canada added pressure on electronics manufacturers by making them liable for the traceability of products they put into the market. Rolando mentioned that manufacturers would partner with different recycling companies in order to trace their products progression from beginning to end uses; however, the cheapest method of recycling happens to be outsourcing to developing countries. Consumerism describes consumer behaviour, as the increase in demand for electronics increases production and therefore increases the amount of waste that needs to be treated.
REMINE, although currently intended for the manufacturing industry, hopes to extend its applications to various industries (e.g. mining, recycling) due to the modularity of our designed system. Collaboration with dominant and ethical e-waste recycling companies, like Call2Recycle, can help decrease the occurrences of unethical business practices specifically aimed to increase profit as opposed to upholding the dignity, respect and safety of workers.
As with every year, there never seems enough time to explore our project to the full extent it deserves. This year was no exception, and with the global pandemic our works seemed even more restricted than usual. However, the iGEM season must come to an end. What follows is a list of next steps and future directives for our project:
It would be of interest to explore the environmental impacts of other common electronic manufacturing wastewater pollutants. This would both be beneficial to help source other metals of value of interest to recover as well as direct the lab and math teams on what proteins to research if we were not to focus on copper.
To look into remote communities and how their wastewater is being addressed. These communities are not as well described within the CAP-EPR but are of interest to our team.
Finally, we would be interested in analyzing the value of extracted copper and compare it to traditional methods of copper harvesting (primarily mining).
References
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