Design 40A - Winter 2013
Research Assignment: Brita Water Filters – The Raw Materials
The products that we use on a daily basis are much like bacteria - we know of their existence and we know of their prominence, yet we fail to critically think about them unless we are explicitly told to do so. As students of design, it is essential to be aware and in some cases almost hyperconscious of the products that surround us. While aesthetics, practicality, and functionality are all important aspects of having a successful product, it is also our responsibility to be conscious of the full process of bringing a product to fruition. The product that we chose to look at are Brita water filters. As human beings, one of our essential needs is accessibility to clean water. This being a class that touches on the issue of sustainability, it seemed appropriate to look at a product that not only provides clean drinking water, but is working to greatly reduce the use of disposable plastic water bottles.
Throughout the duration of this research paper, we will take a look at one of the most important aspects of product design- the raw materials. While visually, the Brita filter seems to be fairly simplistic in both it’s design and material choices, it’s important to delve deeper into the concept and really look at the chemicals, compounds, and other materials that go into creating a single Brita water filter. In addition, we will also explore a concept we have touched upon this quarter - Cradle-to-cradle design, an approach that is a holistic economic, industrial, and social framework that seeks to create systems that are efficient and essentially waste free. We will critically analyze the Brita Filters using three of the five certification criteria: Material health, material utilization, and assessment of energy used for production.
To give myself a solid foundation and a basis to begin researching for this essay, I attempted to communicate and solicit information from Brita themselves. I navigated through their website and found a contact form in which I asked specifically about the plastics that are used in the making of their products. To my surprise, I received a reply less than a week later, though I believe the information is based on a template as I found similar information online. They broke the product down based on the application of the specific plastics. The body of the pitcher are made of either NAS - a styrene based plastic or SAN - Styrene Acrylonitrile; the lids and filter housings are made of Polypropylene plastic; and the handles are made from Santoprene.
Before we delve into the plastics used for the casings and housing of the Brita filter, we should look at the materials that are used to actually filter the water. According to the Brita website, the cartridges contain a combination of ion exchange resin and silver impregnated activated carbon. According to the United States Patent Office, Ion-Exchange Resin was patented on February 1, 1949 with the statement, “This invention related to synthetic resins, and deals particularly with the resins adapted for use in ion exchange in the treatment of water and other liquid [...] Such resins may be used, for example for the removal of hardness in the softening of water for domestic or industrial use”. Generally speaking, resins are organic substances that are found in plant secretions. Further information provided gives us a better understanding of how the resins look in appearance and how they are chemically created, “The resins are prepared as spherical beads 0.5 to 1.0 mm in diameter. These appear solid even under the microscope, but on a molecular scale the structure is quite open. Water is softened by using a resin containing Na+ cations but which binds Ca2+ and Mg2+ more strongly than Na+.” Though the process seems to have an fairly involved chemistry, the environmental implications of creating these ion exchange resins are not bad at all. Chemist David Alchin states, “The waste water for disposal after regeneration contains all the minerals removed from the water plus salt from the spent regenerates. These are concentrated into a volume equivalent to 1-5% of the treated water throughput. Disposal is not usually a problem as the load on waste treatment systems is low compared with at from many other industrial processes”. The second component to the filtration system is silver impregnated activated carbons. Generally speaking, activated carbons are forms of carbon that are processed to be riddled with small, low volue pores that increase the surface area available for adsorption or chemical reactions and are typically derived from charcoal. While activated carbon can be produced using a number of different materials (eucalyptus, saw dust, rice husk, coal, wood, lignite) one of the most popular versions are manufactured from coconut shells as it is harder and has a higher surface area than any other material allowing for greater adsorption. By implementing another chemical process, these activated carbons can be impregnated with silver. According to the patent from 1974, “Metallic silver is impregnated on activated carbon when activated carbon is added to an aqueous solution of a silver salt. For example, 0.1 wt. percent silver activated carbon, which is the composition most frequently used, is prepared by adding activated carbon to about 500 ppm silver nitrate solution”. A simple Google search shows that both of these products are readily available by manufactures from all over the world, although the exact source for use by Brita’s production unit remains a secret. Overall, we see that chemical processes that were patented many years ago, are still being used for implementation in water filtration devices such as the Brita filter.
Now that we have tackled the materials involved in the actual filtration of water, we can look at the plastic components. The production of these plastics are equally important to look at to get holistic sense of the manufacturing process. First, we will take a look at NAS (polystyrene based) and SAN plastics (Styrene Acrylonitrile) which are typically used for the body of the Brita filter. NAS is a trademarked plastic that is very similar to polystyrene manufactured by Nova Chemicals, the largest producer of styrene/polystyrene in North America. Regarding NAS plastic, they state, “it provide stress hazing and surface crazing resistance superior to acrylic, and exhibit virtually no reaction to popular automatic dishwashing detergents, drying agents, and household cleaners. When sterilized by Gamma or electron-beams, NAS resins recover clarity quicker than acrylic, with minimal yellowing”. Aside from the trademark, NAS is not much different from general polystyrene plastics in the sense that it is synthetically based from single moleculed styrene, a liquid petrochemical (deriving from petroleum). In order to create various shapes (as illustrated by the various body types of the Brita filter), the polystyrene is typically either extruded or injection molded. Similarly, SAN plastics are also used in the bodies of Brita filters. IDES Incorporated, a database of technical information regarding various plastics state, “ The SAN copolymer generally contains 70 to 80% styrene and 20 to 30% acrylonitrile. This combination provides higher strength, rigidity, and chemical resistance than polystyrene, but it is not quite as clear as crystal polystyrene and its appearance tends to yellow more quickly”. The difference between NAS and SAN is the addition of acrylonitrile which is another type of monomer based off of the chemical compound C3H3N. It is also considered to be a Class 2B carcinogen, by the International Agency of Research on Cancer. This certainly brings up some concern as that means that it could possibly be carcinogenic. Moving back to the idea of cradle-to-cradle, we can take a look at material health, material utilization and recycling capabilities. In terms of material health the American Chemistry Council states, “Based on scientific tests over five decades, government safety agencies have determined that polystyrene is safe for use in foodservice products. For example, polystyrene meets the standards of the U.S. Food and Drug Administration and the European Commission/European Food Safety Authority for use in packaging to store and serve food”. This is obviously good information to hear, and makes sense considering the product is still being sold. More than likely a product that would be found using unsafe materials would create backlash from consumers and the product would need to be modified or completely discontinued. While these plastics are cannot be recycled, Brita themselves offers a recycling program via their website, where they are taken in and eventually incinerated. In terms of overall waste from the incineration of these plastics the American Chemistry Council States, “, when polystyrene is incinerated in modern facilities, the final volume is 1% of the starting volume; most of the polystyrene is converted into carbon dioxide, water vapor, and heat”.
The next plastic that we must deconstruct is Polypropylene, which in the Brita filters, typically make up the lids and filter housing units. IDES Inc. states, “This polyolefin is readily formed by polymerizing propylene with suitable catalysts, generally aluminum alkyl and titanium tetrachloride. Polypropylene properties vary according to molecular weight, method of production, and the copolymers involved”. It is considered to be one of the most important plastics as it is can be used for a variety of different things and is also affordable. Similarly to the NAS and SAN plastics, polypropylene can also be molded or blown into very specified shapes and designs. One of the advantages to using polypropylene plastics is that it is indeed recyclable. This means that although the body of the Brita Filters cannot be recycled the rest of the unit can be, which can prove to be difficult as the majority of individuals would not bother to separate the various plastics.
The last plastic that is used in the manufacturing of Brita Water filters is Santoprene which is used for the soft-grip handles of many of Brita’s products. Much like NAS was a trademarked type of plastic, Santoprene is a trademarked thermoplastic elastomer, by Exxon Mobil. Exxon states that Santoprene are composed of “high-performance elastomers that combine the best attributes of vulcanized rubber – such as flexibility and low compression set – with the processing ease of thermoplastics”. They continue by stating Santoprene TPVs can be injection molded, extruded, blow molded or thermoformed, and clean scrap from these operations can be reused. Santoprene TPV is recyclable in the polyolefin recycle stream. IDES looks at Thermoplastic Elastomers and states, “ TPEs are a family of polymers that can be repeatedly stretched without permanently deforming the shape of the part. Unlike rubber-like elastomers, they do not require curing or vulcanization, as they are true thermoplastics. Thermoplastic elastomers have replaced rubber in many applications, most importantly the automotive industry” This thermoplastic elastomer is a very small part of the Brita Filter, yet is equally complex in the ways that it is formed and put together.
In conclusion, we see that there is more to a product than meets the eye. It is much more than coming up with ideas, designing, choosing colors, and going into manufacturing. There are actual reasons behind each and every material choice and each of these materials has an embodied energy that most individuals would not tend to think about nor care about. As stated in the introduction, it is our responsibility as designers to keep all of these things in mind. We must be conscious of the choices that we make to not only ensure that our product works well, but to be able to make educated decisions regarding the design process. While I feel successful in the sense that I was able to find information in regards to the majority of the parts of this product, it was difficult to be sure about where and how these materials are obtained by the company as industry trade secrets are usually not found online. I was able to make educated assumptions based on other research and readings that I stumbled upon. All in all, this was an eye opening assignment that required us to dig past the surface and to learn about a dimension of design that often goes unnoticed.
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"Brita: Frequently Asked Question." Brita Incorporated, n.d. Web. <http://www.brita.net/faqs_household.html>.
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Manning, Kevin. “Re:Materials Used in Brita Filters”. Message to Brita. 22 February 2013. E-mail.
Mitsumori, Nobuo, Takeda, Chikahiro, Miyasako, Hideichi. “Method of treating silver impregnated activated carbon” Patent 3,294,572 26 December 1966
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 Manning, Kevin. “Re:Materials Used in Brita Filters”. Message to Brita. 22 February 2013. E-mail.
 "Brita: Frequently Asked Question." Brita Incorporated, n.d. Web. <http://www.brita.net/faqs_household.html>.
 Luaces, Enrique. “Ion-Exchange Resin” Patent 2,460,516. 1 February 1949.
 David, Alchin. "Ion Exchange Resin." (n.d.): n. pag. New Zealand Institute of Chemistry. Drew New Zealand. Web. <http://nzic.org.nz/ChemProcesses/water/13D.pdf>.
 Saha B., Tai M.H., Streat M. Study of activated carbon after oxidation and subsequent treatment characterization // Process safety and environmental protection - 2001. - V.79
 OSMOSIA. Coconut Shell Activated Carbon Factory. “Coconut Shell Activated Carbon” Web. <http://coconutshellcarbon.com/>
 Mitsumori, Nobuo, Takeda, Chikahiro, Miyasako, Hideichi. “Method of treating silver impregnated activated carbon” Patent 3,294,572 26 December 1966
 AMCO Polymers LLC. “Plastics - Nova Chemicals” Web. <http://www.amco.ws/plastics/nova.asp>
 IDES Inc. “Styrene Acrylonitrile (SAN) Plastic” Web. <http://plastics.ides.com/generics/47/styrene-acrylonitrile-san>
 US Department of Labor. OSHA - Toxic and Hazardous Substances: Acrylonitrile. Web. <http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_id=10065&p_table=standards>
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 Staff (2010–2011). "Q & A on the Safety of Polystyrene Foodservice Products". American Chemistry Council. Retrieved 2011-06-14.
 Franklin Associares. "CRADLE-TO-GATE LIFE CYCLE INVENTORY OF NINE PLASTIC RESINS AND FOUR POLYURETHANE PRECURSORS." (n.d.): n. pag. American Chemistry Council. Web. <http://plastics.americanchemistry.com/LifeCycle-Inventory-of-9-Plastics-Resins-and-4-Polyurethane-Precursors-Rpt-and-App>.
 IDES Inc. “Polypropylene Plastic” Web. <http://plastics.ides.com/generics/39/polypropylene-pp>
 "Santoprene Thermoplastic Vulcanizate (TPV)." Exxon Mobile - Chemical, n.d. Web. 13 Mar. 2013. <http://www.exxonmobilchemical.com/Chem-English/brands/santoprene-thermoplastic-vulcanizate-tpv.aspx?ln=productsservices>.
 IDES Inc. “Thermoplastic Elastomer Plastics” Web. <http://plastics.ides.com/generics/53/thermoplastic-elastomer-tpe>
March 13, 2013
The Life Cycle of a Brita Filter through Waste and Emission
Since its inception in Taunusstein, Germany in 1966, Brita has sworn to observe and uphold its mission in providing clean drinking water to millions and reducing plastic water bottle waste through its Brita water filter. However, I will argue that the Brita water filter is more of a danger to the environment, than a solution, according to Brita. In examining the waste and emissions of the Brita’s life cycle through the raw materials acquisition, manufacture, distribution, recycling methods and waste management of a Brita filter. Even though Brita argues in its sustainability mission statement that, “from production to dispatch, the environment is always a prime consideration,” but in terms of their manufacturing practices the environment is not considered when manufacturing a Brita filter. First, one of the raw materials used to produce a Brita filter, coconut shells, are acquired from poorer countries, such as India and the Philippines through harmful practices that have devastating consequences to the natural environments of these countries. In addition, through the three other secondary raw materials; Polypropylene Plastic, Styrene Acrylonitrile, and Polystyrene there is an abundant amount of CO2 emissions produced in just manufacturing one Brita filter. In addition, in promoting sustainability through their corporation mission statement, Brita has implemented a recycling program since 1992, which has been more successful in Germany than the United States, to combat waste. However, this is another issue of contention I will argue that is more harmful than sustainable to the environment, due to the already pollutant plastic products used in the filter and the harsh processes implemented to break down the filter. Finally, although Brita claims to be an environmentally conscious and clean distributor of water filters, it is simply inaccurate and hypocritical, considering the entire lifecycle of the Brita filter, from the extraction of coconut shells in India to breaking down and burning the “recycled” plastic filters in Germany, it emits non bio-degradable plastic waste and C02 emissions into the environment.
There are several raw materials that make up the structure of the Brita filter, one primary material, and the rest include secondary materials because they are not found in the environment, resulting in an unsustainable and toxic product, both for the consumer and the environment. First, the Brita filter is made of granulated active carbon, which originates from the primary raw material coconut shells, located in countries, such as India. According to the Production and Marketing of Coconut in India Report, an estimated 11.2 million coconuts were harvested in India alone, and as a result of this high demand, extraction methods, such as chopping down trees and burning natural land to grow more coconut trees are preferable methods to gaining profit for less developed countries, such as India (Singh). In addition, there are three main secondary sources found in a study by the University of Vermont, which are chemical composites that make up the lightweight and somewhat durable structure of the Brita filter. The first is Polypropylene Plastic (a thermoplastic polymer), in which 248.7 grams is used to make one Brita filter, and consequently emits 845.58 grams of CO2 emissions into the environment. Next, Styrene Acrylonitrile, in which 390.5 grams are needed for one Brita filter, and then produces 1.597145 Kg. of CO2 emissions. Finally, the third main secondary raw material, Polystyrene, using 290.5 grams, emits 128.55 grams of CO2 emissions. Therefore, to produce one Brita filter utilizing these raw materials produces a complete total of 2.571165 Kg. CO2 into our environment. In addition, not only are the production of these raw materials harmful to our environment, but also to consumers drinking from the Brita filters which claim to “clean” water, but at the same time emitting CO2 and harmful toxins from the plastic container itself. According to Environmental Health News, “New chemicals – with unknown toxic properties – are present after heating commercial polypropylene plastics during manufacturing” and as a result is affecting consumers, making it even more that dangerous that scientists are still unaware what specific toxins are affecting us. However, one aspect of the manufacturing process that has made significant progress is through the manufacturing plants and headquarters use of energy. For example, the three major Brita headquarters in Germany, Switzerland, and Great Britain are powered by green hydroelectric power, and the German headquarters is saving 2,540 tonnes of CO2 per year (Brita). As a result, when Brita claims it “cares about the environment” and is helping to make its protect “sustainable”, it should be regarded as an inaccurate and flawed statement based on the how they acquire the raw materials and the manufacturing process of the Brita filter.
Despite its extremely harmful structure, Brita has committed to using transportation in distributing Brita filters that is less harmful to the environment, although they still primarily rely on oil and diesel powered transportation. According to the Brita web site, their transportation includes the following; “90 % land, 9 % air, and 1% sea” (Brita). With their founding base location in Taunusstein, Germany along with other corporation plants located in Great Britain, Switzerland, India, California, and more, their goal is to have an “increased presence globally” to make transportation and distribution of materials easier and more effective. According to Brita, effective global and national routes have made it more efficient for their company to transport goods, however in using land transportation, which typically includes diesel trucks; this is an extremely flawed aspect on Brita’s plan of sustainable progress. However, as an example of their transportation system, to distribute a shipment of Brita filters by a diesel truck from their United States headquarters in Oakland, California, to a Target in New York is a little more than 2,900 miles. According to the United States Environmental Protection Agency, one gallon of diesel fuel emits 10,180 grams of CO2 per diesel truck, and for a Brita filter distributor truck to transport a shipment from California to New York would result in 1,933,333 grams of CO2 (EPA). Brita even admits in a 2007 sustainability report that the company’s methods of distribution and transportation are “still in development in terms of sustainability and protecting the environment” (Brita). Also, according to the Los Angeles Times, “Brita is one of many companies still lagging” in finding a sustainable means to transport its goods, which will only cause continued CO2 emissions and pollutants in our fragile ecosystem (Carpenter). Although there are no sources that go into depth in exactly what routes or what type of specific trucks are used to transport Brita filters, it is clear that by primarily using diesel fueled vehicles to transport products long distances results in a large amount of CO2 emissions. In addition, Brita’s transportation and distribution of its merchandise globally and nationally produce a vast amount of CO2 emissions, based on their primary use of land transportation resulting in another flawed aspect of the supposedly “clean and eco-friendly” Brita filter.
In an attempt to appear more socially and environmentally responsible, Brita was the first water filter manufacturer to implement a recycling program since 1992, which has mostly succeeded in Germany more than the United States, to reduce the amount of filters from ending in waste. However, although Brita claims it can “recycle” a filter, which is very inefficient, to begin with since one only lasts every 2 months for the average family, their form of recycling is severely problematic and should not be considered recycling. According to Brita, every one in five Brita filters are recycled in Germany, and the statistics are unknown for United States consumers, and even though this is a promising start it is still not effective enough to be labeled effective or sustainable change (Brita). First, the consumer either drops it off at a Brita related store or mails it to a Brita headquarter that is closest to them and all the filters are transferred to the Taunusstein headquarters. These are the following steps in Brita’s process for recycling filter: “ First, filters are broken up and the filter material is separated from its plastic housing. Second, the plastic material of the Consumer filters under goes preliminary cleansing and is then ground up. The resulting plastic granulate is passed on to the plastics industry to be reprocessed for various purposes. The plastic materials of the Professional water filters are also passed on for reprocessing. Third, Activated carbon and ion exchangers – the contents of the filter cartridge – are also separated and processed in this special facility at Brita. Fourth, the activated carbon is returned to its manufacturer where it is reactivated and used again for processes such as the treatment of waste water. Fifth, the ion exchangers remain at Brita where they undergo a complete regeneration process in which, over the course of a series of treatment stages, they gradually become just as effective as a new material. Final heat treatment once again guarantees hygienic purity. At the end of this process the ion exchangers comply with all functional and hygienic quality standards that are expected of brand new ion exchangers. This is assured by strict external and internal checks. The recycled ion exchangers are then used for the production of household water filters” (Brita). Although Brita has made notable initiative in implementing a recycle program that could eventually help to stem the amount of waste and CO2 emission caused by Brita filters, however it cannot alleviate the fact that the raw materials will never be able to be bio-degradable or sustainable. In addition, last year Brita sales resulted in $5,193,000; begging the question of how many of these plastic, non bio-degradable filters are already sitting in waste dumps and how many more will be thrown away due to the increasing large demand to purchase unnecessary commodities, such as the Brita filter (Brita). It is impossible to know how many Brita filters have been dumped in landfills, and how many will be thrown away just this year, but in terms of the sales it appears to be disastrous the amount of Brita filters being sold and in our fast paced consumer society they will eventually be thrown away, resulting in more pollution and toxins from the plastic made Brita filter.
In conclusion, by examining the waste and CO2 emissions of the Brita water filter life cycle, I was able to determine that it is an extremely harmful and threatening process both to the environment and consumer’s health. First, the raw materials used are not only toxic and threatening to the environment in themselves, but also the way they are acquired can be extremely harmful to the environment. In using the secondary raw materials; Polypropylene Plastic, Styrene Acrylonitrile, and Polystyrene it creates an inexpensive and durable product, but at a major cost due to each of their relatively high emissions in CO2 and toxins when heated. Furthermore, the types of transportation Brita utilizes to distribute its products, on a global and national scale is also very inefficient and unsustainable. Through a majority of land transportation, along with air and sea, this leads to the company’s dependence on diesel fuel as a means of energy, which produces high amounts of CO2 emissions per gallon of diesel fuel, especially as the main U.S. headquarters is located in Oakland, CA, resulting in great distances of travel for truck routes cross country. In addition, though Brita has attempted to implement various sustainable initiatives, such as providing hydropower energy to power their headquarters in Europe and launching a recycling program since 1992, it will never be enough to reverse the damage they have already done and continue to do to the environment because of the main material manufactured in their product: plastic. Furthermore, as sales continue to rise and demand for unnecessary items like the filter increase; it will take a major toll on the space in our landfills and continue to unleash more toxins in our environment. Finally, although Brita claims to be an environmentally conscious and effective and sustainable alternative to plastic water bottles through their water filters, it is simply inaccurate and flawed. In considering the entire lifecycle of the Brita filter, from the extraction of coconut shells in India to breaking down and burning the “recycled” plastic filters in Germany, it emits non bio-degradable plastic waste and C02 emissions into the environment that will continue to have a serious and devastating impact on our precious environment.
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