Wednesday, July 28, 2010

This Is A Truly Awesome Video, And It's Why I Think The Water Industry Is So Important.


Solidarités International: Water talks from La Boite Concept on Vimeo.

Wednesday, July 21, 2010

Pharmaceuticals & Personal Care Products in Drinking Water: Part 2

Potential Effects

So what are the potential effects of these very low levels of EDC’s and PPCP’s? The effects can be of two sorts: environmental and human health.

Environmental

Environmental issues can arise when the compounds interact with organisms in the environment, especially aquatic organisms. These aquatic critters are particularly susceptible to problems because not only do they drink the water, they are submersed in it. They are in intimate contact with the water, and whatever is in it, 24/7, so any adverse effects from chemicals in the water can be amplified. Studies abound regarding fish and amphibians changing sex, or showing androgynous characteristics due to exposure to EDC’s in wastewater effluent. There are also many indications of effects on invertebrate aquatic species as well. These issues in and of themselves seem sufficient to require monitoring and treatment to remove these compounds from wastewater effluent, thus protecting these susceptible organisms from being exposed. But treatment can be problematic and should be approached with caution. More on that later.


Human Health

Human’s encounter these compounds through the water we drink. Drinking the recommended volume of 2 liters per day, the average persons exposure to these compounds is extremely slight, given that they are present at such very low concentrations (remember, parts per trillion). Although it may seem a little troubling to be drinking something that has elements of someone’s shampoo in it, is it really something that can adversely affect our health? Should we spend the millions of dollars it would cost to remove these compounds? And remember, no big anonymous corporation somewhere can be made to pay for all of this; the problem is a result of the actions of each and every one of us, and we all will pay for any “solution” in our water rates. The answer to these questions is a resounding, “No one knows!”. There is very little, if any, toxicological data regarding consuming any of these compounds, so no one knows what the effects might be, or even if there are any. When it comes to pharmaceuticals, there are large quantities of data on what happens to people when they consume them at vastly higher concentrations for short periods of time, but not on what happens when they are consumed in very low concentrations for long periods of time. And what are the consequences of consuming a mixture of these compounds? Are there synergistic effects, where a mixture can be more potent than the individual compounds separately? Sort of a “The whole is greater than the sum of the parts” scenario? Again, unfortunately, no one knows; even less, if any, data exists on this subject. So should we treat the water we drink for these compounds or not? There’s no easy answer, but maybe looking at what happens when we treat the water will help.

Treatment

 
The treatment techniques for dealing with EDC’s and PPCP’s in wastewater and drinking water are pretty much the same. They consist or reverse osmosis to remove them, or oxidation to break them apart. Oxidation can consist of the traditional technique of adding chlorine, or what’s known as advanced oxidation.

Reverse osmosis consists of using pressure to force the water through a membrane. In theory, the water passes thru and everything else remains behind and is filtered out. But in practice, only some or most of the impurities are filtered out; others pass through the membrane and remain in the water, so it’s only a partial solution at best. In addition, the impurities that are filtered out are still there in a very concentrated form that has to be disposed of by dumping it in the ocean or injecting it into a deep well. Since the EDC’s and PPCP’s still get dumped back into the environment, maybe this is really no solution at all.

Oxidation by chlorination is a common practice well established in the industry and used for many years both to treat for certain impurities and to disinfect the water. However, when it comes to EDC’s and PPCP’s, it does only a very limited job, leaving many of these compounds intact.


Advanced oxidation involves adding ozone or peroxide to the water, then subjecting it to high intensity UV light. This two step process is very effective at breaking chemicals of almost any sort into smaller pieces. But the key thing to remember is that it does not make them disappear; it does not reduce them all the way to their atomic constituents; it simply breaks large molecules into smaller ones. The resulting smaller pieces are still present in the wastewater effluent or drinking water that has been treated. What are those smaller pieces? Are they harmful, either to people or organisms in the environment? Are they more or less of a problem than the chemical compounds we started with? Once again, we have to say we just don’t know, because we don’t even know what smaller molecules we are producing in most cases, much less anything about how they react with humans or the environment.



One chemical that has been studied a bit is carbamazepine, and how it breaks down when subjected to advanced oxidation. The researchers had the following observation in regard to this process:

“The three (breakdown) products were determined to be 1-(2-benzaldehyde)-4-hydro-(1H,3H)-quinazoline-2-one (BQM), 1-(2-benzaldehyde)-(1H,3H)-quinazoline-2,4-dione (BQD), and 1-(2-benzoic acid)-(1H,3H)-quinazoline-2,4-dione (BaQD)…Currently, there are no data available on the biological effects of the formed oxidation products.” Ozonation of Carbamazepine in Drinking Water: Identification and Kinetic Study of Major Oxidation Products Derek C. McDowell,, Marc M. Huber,, Manfred Wagner,, Urs von Gunten, and, Thomas A. Ternes, Environmental Science & Technology 2005 39 (20), 8014-8022

So, the major issues can be broken down into two questions. First, should we treat for EDC’s and PPCP’s in wastewater to protect the environment? The effects of these compounds on the environment are known and demonstrated, so maybe we should. The risk does remain that we could be creating a bigger problem because we don’t know the effects of the new, smaller molecules we are creating in the treatment process. So in addition to treatment, we should implement extensive environmental monitoring. Second, should we treat for these compounds as a part of the drinking water treatment process? There are no known toxicological effects of these compounds on humans, and we have virtually no information on what the breakdown products from treatment even are, much less their toxicity, so maybe we shouldn’t treat drinking water this way. Of course, if we treat wastewater effluent and discharge the breakdown products into the environment, they will eventually find their way into our drinking water (remember the whole water cycle thing), but they could be attenuated by natural processes in the environment before becoming drinking water. That’s something else to carefully monitor.



There are definitely no easy answers to this complex issue. The worst thing that we could possibly do is rush toward regulations and treatment regimens that we have no idea are required, could possibly cause more harm than good, and would substantially increase everyone’s water bills. If you would like more information on this subject, a good place to start is the EPA website at http://www.epa.gov/ppcp/

Monday, July 19, 2010

Pharmaceuticals & Personal Care Products in Drinking Water:
Part 1

Intro

Pharmaceuticals, personal care products, endocrine disruptors, emerging contaminants – all of these terms have been in the news frequently in relation to drinking water, getting tossed around like a soccer ball at the World Cup. But what are they, what do they mean to the average person, and should anyone be overly concerned about them? Let’s take a look at the issue and see.

The Jargon

Endocrine Disrupting Compounds (EDC’s) – These compounds are anything that can interfere with the endocrine, or hormonal systems, of living creatures. Primarily, we are talking about vertebrates, especially people. Compounds in this class include things that we have known about for a long time, like nitrate or atrazine; or chemicals that have been more recently discovered in drinking water sources, such as estradiol or bisphenol A.

Pharmaceuticals & Personal Care Products (PPCP’s) – These obviously include pharmaceutical compounds, like carbamazepine (to control seizures) and fluoxetine, also known as Prozac, which is very commonly found in many water sources; I guess we really are a Prozac Nation (Elizabeth Wurtzel, Riverhead Trade, 1994). Personal Care Products include the literally thousands of compounds found in the products we all use every day, like tooth paste, deodorant, shampoo, and shave cream; and include chemicals that are fragrances, surfactants, disinfectants, coloring agents, preservatives, etc.

Compounds of Emerging Concern (CEC’s) – These are any of a host of chemical compounds not currently regulated, for which little if any toxicological data exists, but which cause concern because of their presence in drinking water sources and in drinking water itself.

If this isn’t confusing enough, many EDC’s and PPCP’s are CEC’s, but not all; PPCP’s can be EDC’s, and vice versa, but not necessarily; and not all CEC’s are PPCP’s or EDC’s. It’s an alphabet soup of acronyms referring to literally thousands of compounds that cause confusion among water professionals and the public alike.

Where are they and how do they get there?

All of these compounds can be found to one degree or another almost everywhere you look:
  • Found in Surface Waters
    • Lakes, streams, ponds
    • Urban and rural areas
  • Found in Groundwaters
    • Wells
  • Found in Finished Water
    • Drinking water plant effluent
    • Drinking water in the distribution system
  • Found in effluent from wastewater treatment plants
    • Water discharged to the environment
    • Water for reuse and recycle projects

These compounds get into the environment from a whole host of sources. The pharmaceuticals taken by people are partially excreted in their urine, which passes through wastewater treatment plants unaffected and wind up in the environment. Hospitals dispose of tons of pharmaceuticals annually, either by dumping them in the sewers or land filling them, where they may potentially leach into the environment. Personal care products are used by all of us every day in fairly large quantities, all of which end up going down the drain, into the waste stream, and out into the environment. These compounds also come from manufacturing facilities, concentrated animal feeding operations (CAFO’s), and agricultural and urban runoff. "The Environmental Life Cycle of Pharmaceuticals ," a diagram by C.G. Daughton of the EPA’s National Exposure and Research Lab in Las Vegas, does a great job of showing the complexities of this issue.


"The Environmental Life Cycle of Pharmaceuticals ," by C.G. Daughton [illustration published in: Daughton, C.G. "Pharmaceuticals as Environmental Pollutants: the Ramifications for Human Exposure," In:
International Encyclopedia of Public Health, Kris Heggenhougen and Stella Quah (Eds.), Vol. 5, San Diego: Academic Press; 2008, pp. 66-102]


The pathways for other PPCP’s and EDC’s into the environment are no less complex. Having said all that, the large majority of these compounds are found at extremely low levels. Analytical results in the range of nanograms per litre (ng/L), or parts per trillion (ppt), are common. To give that some perspective, here’s some comparisons of what a part per trillion means:
  • One inch in 1.6 million miles
  • One second in 32,000 years
  • One cent in $10 billion
  • One square foot of the state of Indiana
  • One drop in 20 Olympic swimming pools
As you can see, a part per trillion isn’t much, but is it significant? We’ll talk about that in the next post.

Sunday, July 4, 2010

The Water Cycle

Early in every child’s education, they begin to be taught about the water cycle; the endless and life giving recycling of our water through our ecosystem. In its simplest form, the water cycle consists of a simple loop, with water evaporating into the air, where it forms clouds that rain water back on the Earth, like this illustration from Northern Michigan University Department of Education for use with fourth grade students:



And it is taught worldwide, as exemplified by this illustration from the Royal Water Processing Unit, located on the West Coast of Andhra Pradesh in India, which has been serving the local community with premium quality ground water since 2002:



As our understanding progresses, we may start to see the water cycle as a bit more complex, like this one from the United States Geologic Survey (USGS):



But in our modern, complex, industrialized world, the water cycle actually looks a great deal more like this:

http://www.recycledwater.com.au/index.php?id=49

The water cycle is as much composed of wastewater treatment plants and agriculture and industry as it is about evaporation and rivers and rain. Unfortunately, we don’t tend to look at it that way, especially those of us in the water industry. We tend to be concerned with only our little part of the cycle, whether it’s the production of drinking water, or the treatment of wastewater, or storm water management. But in order for us to be good stewards of those individual parts of the water cycle, we each need to start being more involved in the entire process.

Compartmentalizing the segments of the water cycle has led to a disconnect with how the entire process works, and the impacts that each of the segments has on the others. Pharmaceuticals excreted or rinsed down the drain pass through wastewater treatment plants and have effects on the environment and show up in drinking water many miles away. Surface water treatment plants drawing water from a major river may dump waste products from the treatment process back into that same river, effecting the environment and other drinking water treatment plants downstream. Storm water may wash oil from streets or pesticides from agricultural operations into rivers and streams, effecting the environment as well as drinking water from treatment plants that draw from those surface waters. Each and every process that uses water affects every other user of water. In other words, it affects each and every one of us.

This is not only an important concept for each and every person to come to terms with, but it is especially important for those of us in industries that are directly involved with water in one form or another. Too often, the many different industries and services directly involved in dealing with water have worn blinders, concentrating only on their particular part and not concerning themselves with how it affects the other parts. But this has to change; all members of the water community must begin to work cooperatively to ensure that our water resources remain clean and healthy for the environment and for ourselves. The emphasis there has to be on the word cooperatively. Storm water management, wastewater treatment, and drinking water treatment need to be seen as a whole, and projects developed that address all of these concerns simultaneously. More wastewater treatment effluent needs to be reused and recycled, whether to recharge groundwater aquifers, in use as irrigation water, for environmental purposes, or for direct potable reuse. Storm water should be treated to remove trash and contaminants and then used to recharge groundwater or for environmental purposes. Drinking water must be conserved through projects such as using grey water for home irrigation, retrofitting with more efficient appliances, re-thinking our concept of a nicely landscaped yard, or taking shorter showers. And regulations need to be developed that disburse responsibilities associated with meeting those regulations equally among all parties involved.

This process has actually begun in water related industries already, and it’s critical to the environment and to the sustainability of our water supplies that it continues, but it has a long way to go. Let’s all hope that it goes quickly and smoothly.