Contami-Nation! A history of pollution and clean-up
The rise of industrial-scale chemical compounds has helped increase our quality of life, but it has also contributed to pollution and contamination of our air and water.
Adriano Cabral: At the 1964 New York World's Fair, the DuPont Chemical Company treated their pavilion's visitors to the world's first multimedia presentation.
Cabral: According to DuPont, a new world was just around the corner made possible by the limitless combinations of newly formed industrial compounds and their ever expanding uses in manufacturing, electronics, medicine and travel.
Cabral: As the showcase of the nation's space age and as a piece of American Cold War cultural propaganda, the Fair suggested there would be no limit to the expansion of the leisure class, a never‑ending improvement in the quality of everyday life. Soon everyone would achieve better living through chemistry.
Cabral: But there was a problem.
Cabral: In 1969, the spark of a passing steel train caused the Cuyahoga River in Cleveland to erupt in flames. A feeder to Lake Erie, the river was so polluted with industrial waste the flames quickly rose five stories and Lake Erie itself was soon declared dead.
In exchange for jobs and a high standard of living, companies had for decades been given a free hand with the nation's waterways without any governmental oversight, but now people across the country could look around them and see pollution everywhere, in the air, in the water and on the shore. As a result, almost 10 percent of the American population protested against pollution on the first Earth Day in 1970.
This forced President Nixon to establish the Environmental Protection Agency in 1970. Congress then passed the Clean Water Act in 1972.
One provision of the bill required wastewater treatment plants to remove the nutrients, nitrogen and phosphorus before returning the treated sewage to natural water sources. This reduced algae blooms allowing more oxygen into the water. Soon fish were returning in greater and greater numbers. The ecosystem slowly began to recover.
Ever since the founding of the EPA and the Safe Drinking Water Act, people have assumed that someone at a municipal agency somewhere is busy monitoring, regulating and removing harmful chemicals from the water, but it isn't quite that simple.
In fact, elements of everything we use to make our lives better from pharmaceuticals and personal care products, to flame retardants, from electronics to nanotechnology, end up in our water, air and soil.
Cabral: The focus on a new class of emerging contaminants began in 2002, when fish suddenly died in large numbers in the Potomac River. These fish and 80 percent of all of the male bass studied afterward were found to have female sex characteristics.
It is believed that exposure to endocrine disrupting compounds produced these results. Because the endocrine system in fish is similar to our own, this created a new worry.
This new class of contaminants is varied, virtually invisible to the naked eye, and it doesn't come from any single source. What exactly is in our water? That's just what Paul Westerhoff and his team are trying to find out.
Paul Westerhoff, PH.D, Professor, School of Sustainability and the Built Environment: Water no matter where you are in the country starts off as rain, it falls and it works its way downhill for the most part, but someone lives upstream. As the water moves down, it keeps getting touched by more and more people, by plants, by animals, by cattle, by agriculture, by other cities upstream.
We have a lot of this upstream wastewater which is in our drinking water supply. By the time the water comes to you, it's gone through a reservoir, down a river, through a water treatment plant.
Brian Biesemeyer, executive director, Scottsdale Water Resources, City of Scottsdale: People expect water in their homes 24/7. They turn on the tap. They expect water. They expect good quality water. The wastewater system we have at the water campus is I think the most advanced certainly in the state and potentially in the country.
Westerhoff: The main objectives of the water treatment plant are to remove pathogens from the water and chemicals from the water. We've employed a number of Engineer Treatment Systems to do that.
Biesemeyer: We look at contaminants both as they come into the system and as they go out of the system. We do monitor some as they come into the system to understand the reduction capabilities of our treatment processes.
Art Nunez, water reclamation director, Scottsdale Water Resources, City of Scottsdale: There's a lot of concern over personal care products, different industrial solvents, there's pesticides, there's by‑products from the chlorination process itself.
Biesemeyer: When water is sent out in the distribution system, it needs to be disinfected to ensure there's no biological contamination.
Nunez: What we do here and what's common throughout the country and many places in the world is use chlorine. We make bleach. You get a weak bleach solution. It's about .8 percent and we apply that for disinfection.
Westerhoff: It's very efficient. It's very inexpensive to use. The down side is it can react with natural materials in water. When chlorine reacts with these, it forms what are called disinfection by‑products.
These are cancer causing agents or carcinogens that we actually produce in our water as a consequence of providing safe microbial water. It creates this dichotomy of having to balance the risk of these disinfection by‑products versus the favorable level of these microbial protections.
Biesemeyer: So to remove those disinfection by‑products, we put granular activated carbon in our treatment facility.
Westerhoff: They actually go through and stick on to the sand and activated carbon. You remove the particles as best you can. Some of the water treatment plants in the valley here use membranes which are essentially polymers like socks and other materials with very small holes in it that would strain out particles that didn't settle out. Then we add some type of chemical disinfectant. Here in Arizona we use ozone.
Nunez: The ozone changes those what's left in the wastewater on kind of a molecular level and it addresses some of those what are termed compounds of potential concerns. It also addresses the formation of the disinfection by‑products.
That's something that we actually learned only over the last couple of years in doing a lot of research and pilot work here with different researchers. We actually did a lot of work with ASU and Paul Westerhoff.
Westerhoff: Our research is emerging contaminants. In the '70s, there were nitrogen and phosphorous. In the '80s, there were disinfection by‑products. In the early 2000s, there were pharmaceuticals that were essentially an offshoot of the biotechnology revolution.
Risk as it turns out balancing these hazards is a function of understanding how much you're exposed to, that is the concentration, and how toxic something is. Just because something's toxic, if you're exposed to a very low amount, your risk is low.
Cabral: How are these contaminants entering the environment? How can we measure what's there? That's what Rolf Halden and his team are studying.
Rolf Halden, director, Center for Environmental Security, ASU: We make and produce over 70,000 chemicals. How many actually get regulated? This is a very, very small amount. Actually, a lot of the chemicals that we use have never been studied in terms of their toxicology and their effect on people but also their behavior in the environment.
In our Center for Environmental Security here at Arizona State University, we are studying the movement and fate of chemicals in the environment and how they get into people and what the effects are. If you go to the wastewater treatment plant, it receives all the water that has been used by people in the city. It draws on the chemistry.
If they touch things and they wash their hands, if they eat or drink things, they excrete some of this. You see a fingerprint of all the chemistry that is present in human society.
One interesting group of chemicals that we're studying are the so‑called halogenated organics. It turns out that this type of chemistry is not naturally occurring at large quantities. It's really a foreign chemistry. It's foreign to nature.
Halden: There's really, really important opportunities to use perfluorinated chemicals, for example, in medical equipment and implants because they don't react and they can't be broken down, they're just perfect to coat surfaces and make joint replacements. They play a major role in medicine.
There also are frivolous uses of chemistry and persistent chemicals. One would be the example of the carpet protectant. Some people might have heard of Scotchgard. The product was actually a coating of perfluorinated chemicals that we applied to our sofas and carpets.
The beauty of the perfluorinated chemicals is that they repel both water and oil. No matter whether you spilled your Coke or some greasy popcorn on your couch or on your carpet, it was easy to remove.
We found out later that the building blocks that we used in order to make these Scotchgard protectants were actually getting into the environment during the manufacturing process and then were moving around and were not being degraded.
We find out that chemicals undergo long‑range transport to the Polar Regions and they rain down. We find that they go into the oceans and move from water into fish and lipids and they accumulate up the food chain. Animals such as the polar bear have an assortment of persistent chemicals in their blood and fat that is detectable.
They have probably the highest body, what we call body burden, the highest concentrations of these types of chemicals. You could say, "Well, who cares, who cares about the polar bear?" But we are top predators too. We consume a lot of meat and a lot of fat, and in that fat is a lot of the chemistry accumulated that we put out into the environment.
Ultimately, we pay the price in having convenience on the one hand in our modern life, but if we don't think it through thoroughly, then we end up in a situation where we contaminate ourselves long term. This is where we speak in generations. Mistakes we make today will lead to exposures in our children, grandchildren, future generations. Actually this can go on for centuries and millennia even.
Cabral: Of all the new contaminants, the newest to enter the environment are contaminants on the nanoscale.
Westerhoff: The nanomaterials are finding their way into every possible product you can imagine you're going to buy, from electronics, to food, to clothing. Nanomaterials are going to make our life better, faster, smaller, prettier. Nanomaterials have the opportunity to be very targeted and to deliver chemical drugs that have benefits, say, for cancer to very specific locations.
The question is what happens when this active nanomaterial with a chemotherapy agent gets into the environment. We can buy many, many products already, things that will have nanomaterial floating around in them to things that have nanomaterials embedded in them, like tennis rackets.
You can buy cutting boards and other things that will have nanomaterial coatings on them. Some will be made out of nanosilver. We have to follow that silver as you wash off the cutting board into a wastewater treatment plant.
Biesemeyer: A lot of that depends on the blend of industry and commercial uses that you have, that any community has. That's certainly something that I know the EPA and others are looking into and investigating an issue being a leader in that area as well.
Westerhoff: What we're trying to look at is understanding these exposure routes into the human body, into fish, into bacteria to understand what the consequences are.
Nunez: The reverse osmosis process is actually removing contaminants based on their ion charge and their molecular weight. We're doing that primarily because of all the concern over the compounds of potential concerns, what's in the water that could eventually make it back into a water source that we're just not even aware of, that we're not monitoring for and that a lot of people are just learning about and talking about it.
Westerhoff: We want to take advantage of these unique properties nanomaterials have that when they get in the environment there's going to be unique consequences that we haven't studied yet.
Biesemeyer: Some may still get through. I think that's where further research is needed to determine what percentage of that is and what the impact that is actually on the environment, is there an impact and what that impact is.
Cabral: Although many of these contaminants derive as a consequence from using things that make the world a much better place, some contaminants are arguably unnecessary.
Halden: A lot of us buy antimicrobial products. Why? Because that's the first stuff we grab when we reach into the shelves of supermarkets. There's lots of antimicrobial products that are being pushed by marketing to the consumers.
Principals of schools and parents get encouraged to buy antimicrobial school supplies. Markers, highlighters are containing antimicrobials, triclosan, and so forth.
Biesemeyer: We have found some triclosan, which is a disinfectant product that's used in antibacterial soaps and other materials.
Halden: Do we need antimicrobial products that are loaded with persistent chemicals? Sometimes, yes. If you undergo an operation in a clinic, I think it's a great idea to have these types of products, but for the average consumer oftentimes there is actually zero benefit of adding this type of persistent chemistry to a regular soap.
There have been studies including those by the Food and Drug Administration, an expert panel that decided that there is no measurable benefit of using these compounds in the household. If we use it and wash our hands, the contact time between the chemical and the bacteria on our hands is too short for the chemical to be effective.
The chemical is being washed into the sewer. The sewer takes it to the wastewater treatment plant. The wastewater treatment plant removes as much as it can but it can't deal with these chemicals very effectively.
About half or three‑quarters of the mass of these chemicals coming into the plants ends up in the sewage sludge. The sewage sludge then is applied on land and it doesn't degrade very quickly either there. It is actually taken up sometimes by plants and can make it back into the food supply.
We actually breed antimicrobial resistance to drugs that are in clinical use. We know that as we use more and more antibiotics and antimicrobials these chemicals actually become less and less effective and it takes many, many lives every year.
This is a huge public health problem and it's really an educational issue. People don't know about it. They have no sense that the chemicals that they get in their personal care products potentially have harmful effects on the environment and they are left with the belief that they actually help.
I think if we would put into the marketing message that you can detect triclosan in 99 percent of breast milk samples from US women, if that message would get out, people wouldn't buy all these products.
Cabral: In order to reach a point where consumers, industry and government can seriously consider these contaminants of emerging concern, more research is needed.
Westerhoff: The European Union takes its precautionary principle, they want to understand the outcome before damage is caused. I think in the US we're a little bit more willing in embracing of technology I think because we assume that companies are going to try to think about the potential to be sued or litigation over release of chemicals.
There is a long history of release of solvents into the environment of Superfund sites that have become grossly contaminated where now industries have to spend billions of dollars.
Halden: We become repositories of persistent chemistry that we churn out into the environment.
Cabral: But what if we could clean wastewater and produce energy at the same time? That's what a new startup called ARB Source is trying to achieve.
Mark Sholin, founder and CEO, Arbsource: The core of our technology is a naturally occurring class of bacteria called Anode‑Respiring Bacteria. That's A‑R‑B. The acronym is where our name comes from. If our patent pending ARB cell biotechnology process, these A‑R‑B that we grow inside of reactors, form this bio‑film.
This bio‑film enables the fast, efficient degradation of sugars, starches, proteins and other organic pollutants that are common in food and beverage wastewater streams.
The sugars and starches that flow into our reactor, they're dissolved in this wastewater. Our bio‑film eats up those materials. We end up with a much cleaner effluent output which then can be safely discharged into either municipal sewer systems or directly into the environment and as a consequence the cool electrochemistry is that we generate this hydrogen gas by‑product at very high, consistent purity. We're talking over 99 percent. It can be used for any number of different purposes.
Cesar Torres, science advisor, Arbsource. Professor, The School of Engineering of Matter, Transport and Energy, ASU: The traditional wastewater treatment plant that uses oxygen, you have to pump that oxygen, that air into the wastewater. That is highly costly for the treatment. At the same time, you produce a lot of bio mass, because they grow with a lot of energy.
The concept of the microbial electrochemical cell is now that we are going to extract some of that energy that we give to the bacteria so they grow a bit less and we get some energy out. There are a few benefits, saving hydrogen production and less biomass to handle.
Matthew Dion, lead design engineer, Arbsource: Where wastewater processing is so vital to our existence and so to be able to reduce some of the energy demand on that is extremely important. I think what we're doing is going to be able to help immensely.
Sudeep Popat, Ph.D, science advisor, Arbsource and The Swette Center for Environmental Biotechnology, ASU: In the case of the development of microbial electrochemical cells, it's a very broad range of disciplines, expertise that is needed to scale these systems up. The congregation of all these researchers with different backgrounds and working on the same technology but different aspects so that those different aspects can be improved to eventually get a more efficient technology has helped a lot in the development of these systems.
Cabral: Instead of simply perfecting this idea in the lab, Arizona State University is attempting to set this technology loose in the outside world via the marketplace.
Sholin: The best part about having ASU, and specifically The Biodesign Institute, as a strategic partner in our development is that they bring world class expertise to our scaling efforts.
Dion: One of the advantages of entrepreneurship versus just a pure lab research setting is that we're getting feedback from customers. Mark talks with the customers and figures out what exactly their needs are and what excites them as far as different parts of our value proposition.
That helps the lab research group to really focus their efforts instead of maybe pursuing a direction that would be cool from a scientific standpoint but not very helpful from a customer standpoint.
Sholin: We'll be adding so much value to the way that water is managed, in the way that waste is converted from what is right now a costly liability into a valuable resource in the form of that hydrogen gas.
Cabral: So how safe are the contaminants in our water? Do they accumulate in the environment or in us over time? The answer in short is we don't yet know.
Halden: Humanity has decided that there is something like waste, but if you look at nature, in nature there is no waste, because every input goes into a system and creates an output, but the output again becomes an input. If that wasn't so, then we would have a dead end machinery that would come to a standstill. We don't see that in nature.
Halden: We're in the process as a society right now to produce a lot of things that are incompatible with this nicely tuned machinery.
Westerhoff: We have to re‑evaluate the wastewater treatment plants and maybe think of new ways to operate them. One of these new ways we're looking at here at ASU is instead of calling it wastewater treatment, to look at it as a resource recovery treatment plant.
The bacteria that grow in a wastewater treatment plant right now, we can extract the oil out of these bacteria for fuel. The things that are left are the nanomaterials that turns out we can remove them.
All the pharmaceuticals, all the flame retardants, all the triclosans of the world that have stuck to the bacteria, we can essentially as we're recovering the oil in these metals, we're oxidizing them to carbon dioxide and harmless by‑products.
Cabral: Creative ideas, careful scientific monitoring, municipal improvements and innovative solutions in the private sector will all be needed to keep our environment safe as we continue deploying new and ever more sophisticated chemistry to maintain and expand our lifestyles.
Sholin: Entrepreneurship is really the best way to enable that development pathway. It's not just about writing a research paper, getting it published and to be done with it. We actually want to take this stuff and push it out as quickly and as effectively as possible.
Halden: We can't really say that there is a bad chemistry because chemistry is not good or bad by design. It is what it is. The choice is with us as a society of how we use these materials.