Pharmaceuticals in the Nation's Water
The Senate is holding a hearing on pharmaceuticals in water, and the USGS is supplying information. Herb Buxton, USGS Toxic Substances Hydrology Program Coordinator, fills us in on related research and findings.
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Welcome and thanks for tuning to this episode of CoreCast. I'm Jennifer LaVista. Today the Senate Environment and Public Works Sub-Committee on Transportation Safety, Infrastructure Security and Water Quality is scheduled to hold a hearing on pharmaceuticals in water. USGS Associate Director for Water, Robert Hirsch, is a witness at this hearing.
Joining me on the phone is USGS Toxic Substances Hydrology Program Coordinator, Herb Buxton, who will fill us in on the research and findings done on this topic. Herb, thanks for joining us.
Well, thanks very much for inviting me.
Why and when did USGS get involved in research on pharmaceuticals in water?
Well, in the late 1990's we took notice of results of some of our European colleagues who had measured a heart medication in the North Sea. They were actually looking for a pesticide. And these results made us realize that there must be something with the way we use chemicals and we handle their disposal that's allowing them to be measurable in such a large water body. And that made us realize that we should be taking a second look or a closer look at these chemicals in the environment.
Explain what you mean when you suggested the way we handle our waste affects the environment.
Well, the waste that we flush, the wash waters that goes down our drain, these all have chemicals in them, chemicals like anti-bacterial soap we have on our counters, the detergents that we use, fire-retardants that my be in the clothes that we wash. These chemicals all go down the drain and they go through waste-water treatment plants.
But the waste-water treatments are not really designed to remove those trace-organic chemicals. And so, where the waste-water treatment plants may discharge to the stream, these chemicals can be found. They also could be concentrated through things like the septic systems in our homes where they go out through the wastes in our homes and they infiltrate to the groundwater system through our septic systems.
And another interesting source is animal feeding operations where there may be thousands of animals on a facility that each may get a therapeutic dose of a drug and then those wastes can enter the environment either through run-off or through application of the solid or liquid wastes to land as fertilizers.
Tell me about some of the research USGS is doing on pharmaceuticals in water.
Well, in 2002 we published our first major findings. These described the occurrence of pharmaceuticals and a number of other waste-related chemicals in the nation's streams. And I think this really defined the issue in the United States. Since then we published over a hundred-sixty papers on things like characterizing the contributions of pharmaceuticals and other chemicals from different specific sources like waste-water treatment plants and animal-feeding operations.
We've also defined the levels and mixtures of these chemicals that you find in various environmental settings and we've also characterized the potential uptake or effects on aquatic or terrestrial organisms of exposure to some of these chemicals.
Which chemicals are of greatest concern and what are their potential effects?
Well, first I should explain that we don't just investigate pharmaceuticals. In fact there are a wide range of chemicals that we consider to be chemicals of emerging environmental concern. As explained, these are detergents, fragrances, fire-retardants, disinfectants, plastics, insect-repellant chemicals and many other chemicals that are used in our homes or our businesses or places of work.
And the reasons that we look for many of these is because sometimes it's more than one type of chemical that can have a similar effect. Chemicals can interact. Their effects can be additive. They can be synergistic or antagonistic, in other words, they can affect the way each other affects an organism. And so it's very important to look at the whole suite of chemicals in the water that, say, a fish is exposed to, because that's the mixture of chemicals that is going to affect the fish.
We believe there are several potential areas of ecologic concerns that are a priority for research. Endocrine disruption and anti-microbial resistance are examples of two important ones. Endocrine disruption happens when exposure to certain chemicals interferes with the body's endocrine system. It can produce developmental or reproductive, neurological or immune related effects. Mixes of chemicals can cause this happen, the natural hormones that are created in the bodies of organisms, for example, estrogen, the female sexual hormone, is one. Also the synthetic chemicals, like the active ingredient in birth control pills is a synthetic estrogen. But there are also some of these other chemicals that we find in our waste waters that can mimic the effect of estrogens because of similarities in the way the molecules are formed.
And so, again, this is another example of why we want look at a wide range of chemicals that are actually in the water supply. Anti-microbial resistance is another example. And we're all used to our doctors advising us to make sure we take all the antibiotics in our prescriptions. That's to make sure that the bacteria in our bodies that are causing our disease or illness are all killed. And some of them don't survive with a resistance to the antibiotic that we took. But certainly when we reduce antibiotics to the environment, there's some concern that that release may expose micro-organisms in the environment and it may encourage the development or maintain the development of antibiotic resistance in an organism in the environment. And that's also a concern.
And similarly with anti-microbial resistance, it's not just antibiotics that could affect anti-microbial resistance. Exposure to some metals and perhaps even some pesticides can develop antibiotic resistance. And so, again, it's important to look for the range of chemicals that microbes would be exposed to in the environment.
Are there any other ecological effects regarding pharmaceuticals in the environment that we should be concerned about?
It's hard to give a good answer to that question. There's research being conducted now and as results come in we'll get more clarity to that answer. Some of the effects that are found, to some degree, are anticipated. Take, for example, the finding that antibiotics in the environment can affect the soil bacteria. Well, antibiotics are designed to affect bacteria. So that effect did not completely surprising although it's important to determine whether or not the bacteria in the soil are affected by the levels of antibiotics that we see in the environment, which are much lower than the doses that are prescribed to people or animals.
But there's also unanticipated effects, and a good example is decimation of a vulture population in India and Pakistan. They were actually exposed to anti-inflammatory drug that was given to cattle. And when the vultures feeded on the carcasses of the cattle they were exposed to this non-steroidal anti-inflammatory drug and suffered severe renal failure. Typical papers in the scientific literature tests for effects of several pharmaceuticals on several species and they may find an effect on one or a combination of pharmaceuticals on one of the tested species.
So, I think really, we're looking for more scientific research to come in here to give a much better understanding of what the environmental implications of pharmaceuticals in the environment are.
Do we have enough information now to know if actions should be taken to protect people from exposure to pharmaceuticals that may exist in drinking water?
The USGS does not conduct all the scientific research needed to make such assessments. We do not conduct human health related research and we have no regulatory responsibility in this area. However we work very closely with the US EPA as part of the process that they implement for protecting public drinking water. This process considers new chemicals and develops standards for chemicals in drinking water.
USGS is one of the number of sources of information that USGS uses on the levels and mixtures of chemicals like pharmaceuticals in groundwater and stream water that is used for drinking water. We have, and will continue to provide, information on pharmaceuticals in the environment as part of this process.
What can we do about this issue? Are there ways that we can help?
There are a number of things that we can do and that are being done already. Actually last year the White House Office of National Drug Control Policy issued guidelines for disposal of end-use medications. It largely involves mixing most drugs with an undesirable substance like coffee grounds or kitty litter and disposing of them in the trash. There are also a number of drug recon programs that are sprouting out around the country. This is where people can return their unused drugs to be disposed of effectively. [Jennifer: Uh-huh.]
Also industry has expressed significant interest in getting more information on the relative performance of different water and waste-water treatment processes. So they can make more informed decisions when they improve or invest in new treatment alternatives.
Herb, is there anything you'd like to add?
Just that we try to make all our results and the data that we collect available on the internet and if anybody would like to find out additional information, they should try our USGS Toxics Program website.
Herb, thank you so much for joining us.
And thanks to all of you for listening. To learn more about pharmaceuticals in water, log-on to toxics.usgs.gov. CoreCast is a product of the US Geological Survey, Department of the Interior. Until next time, I'm Jennifer LaVista.
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"Nobody's Dirty Business" by Mississippi John Hurt
Resources related to this podcast
- Statement of Robert M. Hirsch, April 15, 2008, before the Committee on Environment and Public Works, Subcommittee on Transportation Safety, Infrastructure Security and Water Quality, regarding pharmaceuticals in the environment is available online.
- Toxic Substances Hydrology Program
- Emerging Contaminants