PPCPs' Double Life
Experts are concerned about the potential health and environmental impacts of contaminants from pharmaceuticals and personal care products that survive municipal wastewater treatment
Each and every one of us contribute to water pollution. "Not I," you
say? Well, if you use personal care products, such as shampoos, lotions, or antiperspirants,
you do. If you take any kind of medication, over-the-counter or prescription,
you do. Each year, thousands of tons of chemicals from pharmaceuticals and personal
care products (PPCPs) infiltrate our environment with little or no resistance.
PPCPs include all drugs, over-the-counter and prescription, and any products used
for personal care, such as fragrances, cosmetics, sunscreens, antiseptics, and
soaps. In the United States, the top prescribed drug in 2005 was hydrocodone with
more than 100 million prescriptions, and according to the American Academy of
Dermatology, and the average adult uses at least seven different skin-care products
each day. And many households dispose of expired or unwanted medication by simply
flushing them down the toilet.
A Big Dose of Reality
PPCPs live a double life. We need many of them to stay hygienic and healthy,
but they are believed to adversely affect the environment. Whenever we pop a
pill, its effects continue long after the ailment is alleviated. In fact, up
to 90 percent of oral medications pass through our bodies unchanged, and those
compounds end up at water treatment facilities that are not equipped to remove
them. The same is true for chemicals from personal care products. Aside from
the aesthetic results, chemicals from products that are applied topically are
easily washed off and end up in the environment. Researchers at the Johns Hopkins
Bloomberg School of Public Health found 75 percent of triclocarban, an ingredient
found in antibacterial hand soap, which is toxic when ingested, remained intact
after treatment in a wastewater facility. It accumulates in wastewater sludge,
which is then used to fertilize citrus fruit, soy bean and carrot crops.
"Typical wastewater treatment facilities, secondary, and tertiary treatment
plants are not designed to remove PPCPs from wastewater," said Karin North,
associate engineer with the City of Palo Alto's Environmental Compliance Group.
PPCPs are currently unregulated, and with no means of specific removal, municipal
wastewater, health, and environmental professionals are concerned. PPCPs are
constantly flowing into the environment with unknown cumulative and synergistic
effects. They are designed to produce biological effects, even at therapeutic
doses, which means that even at low concentrations, they remain active and may
deviate from their original intent and cause different reactions in the environment.
Mounting Evidence
Recent monitoring studies have found low trace levels of PPCPs
in the parts-per-trillion and -billion, comparable to one drop in an Olympic-sized
swimming pool, in soils, sewage treated effluent, surface water, groundwater,
and even drinking water around the world. In Canada, researchers at Edmonton's
Enviro-Test Labs, found carbamazepine, an epileptic drug, and emfibrozil, a
cholesterol reducing drug in the drinking water of four cities. Germany has
been studying PPCPs for the past decade. Thirty-one different PPCPs were found
in 40 German rivers and streams. The antidepressant, fluoxetine, better known
as Prozac, was found in trace amounts in groundwater in England. The most notable
state-side study was conducted by the U.S. Geological Survey (USGS) in 1999-2000,
where 139 rivers in 30 states were tested and found that 80 percent of streams
contained 31 different drugs. U.S. studies have also confirmed the presence
of PPCPs, such as naproxen, estrone, and clofibric acid in drinking water. Thanks
to new technology capable of detecting low concentrations, it is no longer a
question of if these compounds are in our waters -- they are. A flood of new
questions has emerged with no answers; most importantly, what are their effects?
Side Effects
We are ingesting low traces of medication we don't need or want. Sensitive
populations, particularly pregnant women and children, are believed to be most
susceptible to any negative effects, but studies have not shown any impacts
on human health as of yet. The Biogeochemistry Research Group at Harvard School
of Public Health is currently studying PPCPs to develop a ranking system to
identify which compounds pose the most significant threat to humans and the
environment.
To date, most of the research has been focused on aquatic environments. There's
a lot we don't know yet, but what we do know is that PPCPs are blamed for various
negative effects on marine life. Populations of male fish are being feminized
when exposed to wastewater containing low concentrations of estrogen from oral
contraceptives. They are growing ovaries, suffering from low sperm count, producing
egg proteins usually found only in females, and in some cases, trying to lay
eggs.
Antidepressants, including Prozac, Zoloft, and Paxil have been linked to significantly
delayed metamorphosis in amphibians, which may seriously impact their survival
rate. Fish and amphibians are sensitive to subtle environmental changes and
serve as biological indicators that may predict future effects on other species.
Increased use of antibiotics has created antibiotic-resistant pathogens, and
trace compounds from antibiotics may exacerbate the problem. USGS found ampicillin-resistant
bacteria in every U.S. river tested in 1999. Combating drug-resistant bacterial
strains will require more expensive and more toxic alternatives, which, without
PPCP removal, will only cause a cyclical, snowballing effect.
What Works and What Doesn't
Municipal wastewater treatment facilities are not always successful in removing
PPCPs from wastewater. "There are thousands of PPCPs, each chemical with
different characteristics, some are water soluble, some tend to sorb into solids,
and some are a little of both. Therefore, some PPCPs are removed or degraded
during the normal treatment process and some are not," North said. "Many
PPCPs sorb into solids which are often land applied. The sheer volume and constant
input of PPCPs to the wastewater treatment plant results in a constant discharge
of PPCPs to the environment, which results in a pseudo-persistence."
The EU project, POSEIDON, was formed to assess technologies for PPCP removal.
Participants in this project included researchers from various European countries,
such as Germany's Federal Institute of Hydrology and ECT Ecotoxicology Gmbh;
Eawag; the Swiss Federal Institute of Aquatic Science and Technology; France's
Suez Environment and universities from Finland, Austria, Spain, and Poland.
The final
results were published in June 2005. They indicate:
- Biological degradation and sorption are the main mechanisms for PPCP removal
during municipal wastewater treatment.
- Ozonation of treated effluent substantially reduces PPCP content.
- Some PPCPs are degraded significantly during anaerobic sludge digestion.
- Removal by sorption onto suspended solids is an important mechanism for hydrophobic
and positively charged compounds.
- Stripping is not relevant for PPCP removal in state-of-the-art municipal wastewater
treatment.
- A rough estimate of PPCP concentration in raw wastewater is directly proportional
to the amount of PPCPs sold.
- During irrigation and soil passage, most of the PPCPs (more than 80 percent)
are sorbed or degraded. However, the irrigation can lead to a pollution of
groundwater with iodinated contrast media (ICM).
- Ozonation or advanced oxidation processes (AOPs) are able to substantially
reduce the contamination of groundwater prior to irrigation of treated wastewater.
- Acidic drugs, such as diclofenac, bezafibrate, and ibuprofen that are removed
easily during wastewater treatment are subject to additional removal during
post- treatment steps like polishing lagoons, gravel filters, or infiltration
ponds. Conversely, neutral substances, such as diazepam and carbamazepine,
that show poor removal rates during wastewater treatment, remain stable during
post-treatment steps as well as in the groundwater. The polycyclic musks tonalide
and galaxolide were significantly removed during wastewater treatment and
post-treatment steps, but showed no significant further reduction during groundwater
flow.
- With few exceptions, coagulation and flocculation are inappropriate to remove
PPCPs.
- Ozonation is a very effective treatment process to oxidize PPCPs. Currently,
there is no indication that the formed oxidation products are toxic.
- Disinfection with chlorine and chlorine dioxide does not lead to a general
oxidation/removal of PPCPs. Only a few PPCPs were transformed.
- Activated carbon is a powerful process to remove PPCPs. Only a limited number
of PPCPs, such as iodinated contrast media and the antibiotic, sulfamethoxazole
show insufficient affinity to activated carbon.
- Nanofiltration and ultrafiltration/powdered activated carbon (PAC) are powerful
processes to remove PPCPs.
What Can We Do Today?
Most wastewater professionals agree that the first step is source control. One
way to accomplish this is by educating the public about how to properly disposal
of medication. "We must first look at the low-hanging fruit, which is the
unwanted or expired medication that people have historically and traditionally
been told to flush down the toilet as poison control measures, North said. "Now,
we would rather people bring them to their health hazard waste site or to a
collection event."
Currently, pharmacies in the United States are not allowed to accept unwanted
or expired medication, but in May 2006 the Bay Area Pollution Prevention Group
(BAPPG) held Safe Medicine Collection Events at 32 locations throughout the
San Francisco Bay area. More than 3,500 pounds of unused or expired medications
were collected at senior centers, city hall, and pharmacies, mostly Walgreen's.
"The goal is to provide residents with an easy disposal option and to increase
public awareness," North said.
As the United States is still in the pilot-program stage, Europe, Australia,
and Canada are leading the way in instituting permanent medication-return programs
at pharmacies. The National Return and Disposal of Unwanted Medicines, known
as the RUM program in Australia, allows the return of unwanted or expired medication
to any pharmacy, at any time. The medicines are then incinerated. The government
pays for disposal and advertising. The RUM program started in 1998 and collected
696,241 pounds of unwanted or expired medication in 2005. Canada has a similar
program that collected 52,800 pounds in 2004.
Unknown Fate
The U.S. Environmental Protection Agency (EPA) began formally tracking pharmaceuticals
and PPCPs in 2002 and is conducting research to determine potential negative
effects.
"The EPA formed the Federal Inter-Agency Task Group on Pharmaceuticals
in the Environment in January 2006, with a goal is develop research strategies
by 2007," said EPA spokesperson Enesta Jones. "PPCP research has also
been identified as one of the top 14 short-term, cross-regional priorities."
PPCPs are on the map, but it will be years until we learn the results of all
these studies. As we wait, the use of PPCPs will certainly continue, if not
increase, only adding to a larger problem to clean up years from now.
Is My Water Safe to Drink?
With the public becoming more aware of PPCPs, municipal utilities will
be receiving calls from concerned residents. Though there are not a lot
of answers yet, utilities have a responsibility to calm their concerned
customers. Here are some suggestions, courtesy of Southern Nevada Water
Authority, for representatives of municipal drinking water and wastewater
treatment plants when communicating with the public:
- Keep in mind, to the average person "parts per billion/trillion"
means contaminants are present, and that causes concern. They feel as
though water should be contaminant-free. This is impossible, so if a
contaminant doesn't warrant removal, the reason must be explained.
- Due to the lack of answers, the public needs to feel that utilities
are taking a serious, proactive approach. Use lay terms and everyday
language instead of technical jargon to describe current measures. For
example, "We're working hard to find out whether or not these compounds
are harmful at low levels, and if they are, we will try to figure out
the best way to remove them."
- Give them real-world examples of other sources of exposure. For example,
soy products such as tofu, soy milk, and soy sauce contain millions
of times more estrogen than drinking water containing trace concentrations,
or stress how someone would need to drink hundreds of thousands of gallons
of water every day to match one Advil tablet.
- Never use cost as a reason to avoid implementing new or additional treatment
options.
- Assign a primary contact who is knowledgeable and friendly to discuss
the issue with the public.
- Develop and maintain a Web site on the topic and include articles from
agency publications. Customers will feel their utility is staying current
and wishes to serve as a source of information.
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U.S. Universities Involved in PPCP Studies
Harvard University
Columbia University
Duke University
Johns Hopkins University
Tulane University
Villanova University
Carnegie Mellon University
State University of New York at Stony Brook
Washington State University
Baylor University
University of Cincinnati
University of Washington
University of Delaware
University of North Carolina
University of Alaska Anchorage
University of Kansas
University of Arizona
University of Hawaii
University of Georgia
University of Tennessee
University of New Mexico
University of Minnesota
University of Oklahoma |
This article originally appeared in the 09/01/2006 issue of Environmental Protection.
About the Author
Sherleen Mahoney is a Web managing editor at 1105 Media.