Pharmaceuticals in Water

advertisement
Pharmaceuticals in Water
MANE 6960H01
Professor Ernesto Gutierrez-Miravete
Fall 2013
Sarah Mahon, P.E.
Table of Contents
1.0
2.0
3.0
4.0
5.0
6.0
7.0
Introduction
Entry Methods into Environment
Detections of PPCPs in Environment: Quantities and Locations
Effects of Pharmaceuticals in the Environment
Current Treatment Technologies
How to Address the Issues
Conclusions
1.0 INTRODUCTION
Contaminants of emerging concern (CECs) are increasingly being detected in the environment
including source water, treated drinking water, and treated wastewater. A significant number of these
CECS are pharmaceuticals and personal care products (PPCPs), including over-the-counter drugs,
prescription medication, veterinary drums, fragrances, and cosmetics. Although PPCPs are most
frequently detected in water in parts per trillion, there is a concern about the effect on humans and
aquatic organisms since certain products (specifically pharmaceuticals) are specifically designed to
affect living tissue at very low concentrations. In addition, people consume drinking water every day;
small quantities of a combination of pharmaceuticals ingested daily over a long-period of time may
have negative effects on human health. There are also potential consequences for wildlife,
specifically aquatic wildlife, that are exposed to these chemicals.
The effect of pharmaceuticals in drinking water is a relatively new field of study, and there are still
huge data gaps. This paper seeks to explore how PPCPs are entering the environment, studies into
the quantities detected in the environment, studies into environmental and human health effects,
and potential treatment or reduction of PPCPs into the environment.
2.0 Entry of PPCPs into the Environment
There are several mechanisms by which PPCPs can enter the environment, including but not limited
to the following:

Unmetabolized pharmaceuticals: The human body does not completely metabolize
medications. As a result, unmetabolized medications are excreted through urine and feces.
This can be a significant problem for people with septic systems; antibiotics and certain
strong medications used in chemotherapy can kill or retard the growth of bacteria necessary
for the operation of the septic treatment system. An overabundance of antibiotics or other
strong medication can cause septic tank failures. Sewage discharges to sanitary sewers are
transported to municipal wastewater treatment plants, which are currently not designed for
the treatment of pharmaceuticals.

Flushing: Unused and expired medications are frequently disposed by flushing medications
down sinks or toilets. This is frequently done by residents who have been told flushing is the
safest means of disposal (to prevent drugs being taken out of their trash and sold illegally).
There are also many residents who don’t know how to properly dispose of prescription
medication and don’t have access to “take-back” programs that some municipalities sponsor.
Some hospitals and long-term care facilities also flush pharmaceuticals due to complex
legislation regarding the disposal of medication; flushing is a low-cost, legal means of
disposal (see Controlled Substances Act below for more details).

Direct release: Some medications are applied topically. These medications can be
discharged directly to open waters by bathing/swimming activities. In addition, these
medications can be discharged to septic systems or sewage treatment plants through
showering activities.

Disposal from drug labs / illicit drug use: Drug labs have the potential to discharge
drug-contaminated water to septic and municipal wastewater systems. In addition, drug users
may flush drug stashes if they fear authorities may discover the stash.

Surface water runoff from agricultural fields: Many farmers use a variety of medications
to protect their livestock from certain diseases and bacteria. Similar to humans, livestock do
not metabolize all the medication and excrete excess medication through urine and feces.
Runoff from agricultural facilities can discharge directly to rivers and streams or infiltrate
into groundwater, contaminating waterbodies and/or groundwater.
Institutions such as hospitals, hospices, long-term care facilities, health care clinics, doctors offices,
and veterinary offices have the potential to dispose of large quantities of pharmaceuticals. As a
result, the Environmental Protection Agency (EPA) conducted a study of disposal practices at these
facilities. The study focused on medications that people don’t take, expired materials, and residuals
in dispensers (such as the contents of intravenous bags). The study found that there is no current
standard of disposal, and the frequency of “flushing” medications varied widely. For example, a
study conducted in 2007 of Santa Barbara, California hospitals indicated infrequent drain disposal;
however, a 2008 publication by Kansas State University concluded that 59 facilities studied disposed
of pharmaceuticals down the drain 46% of the time. (Unused Pharmaceuticals in Health Care
Industry - Interim Report, EPA)
Controlled Substances Control Act
There are a wide variety of regulations regarding the disposal of expired medication; some medicines
are regulated by federal government as hazardous waste under the Resource Recovery and
Conservation Act. Other medications, such as narcotics, opiates, and stimulants are regulated by the
Controlled Substances Control (CSA) Act. There are three methods for facilities to dispose of
medications subject to the CSA:

return to manufacturer,

destroy the medication (flushing is an acceptable means of destruction),

transfer medication to a reverse distributor
Facilities need to be registered with the CSA to return medication to the manufacturer or to transfer
medications to reverse distributors. Most long-term care facilities are not CSA registrants due to
cost, complexity, and time commitment it takes to be CSA-certified. As a result, most long-term
facilities are required to destroy the medication, and many choose flushing since it is easy, cheap, and
accessible. Due to additional regulatory restrictions in some areas (such as a ban on redistributing
medications in Arizona, Kentucky, Mississippi, New Mexico, and Texas), there are few disposal
opportunities for certain institutions.
3.0 Detections of PPCPs in Environment: Quantities and Locations
In August 2009, the EPA published a report “Occurrence of Contaminants of Emerging Concern in
Wastewater from Nine Publicly Owned Treatment Works”. In the study, the EPA discusses how
after testing for pharmaceuticals at four treatment plants, they discovered that analytical methods
were not developed to meet the needs of the study. As a result, the EPA developed methods for
detections of PPCPs during the course of the investigation. The report specifically cautions about
interpreting the results since the analytical methods used were under development during the study,
causing data quality issues during laboratory analysis. The methods developed include EPA Method
1694 for Pharmaceuticals and EPA Method 1698 for steroids and hormones. The methods can
measure up to 27 steroids/hormones and 74 prescription or OTC drugs.
The Table 5-3 below identifies total quantity of PPCPs identified in wastewater treatment plants
influent and effluent during the EPA study. Note: “groups” signify which analytical method was
used for PPCP detection.
Even though EPA Methods for testing for pharmaceuticals are relatively new, there are still a variety
of studies that have been completed documenting the presence of PPCPs in water.
According to an article from Donn, Mendoza, and Pritchard, the following are results of studies that
have been conducted throughout the United States:

In Philadelphia, 56 pharmaceuticals have been detected in treated drinking water (including
medications for the treatment of pain, infection, high cholesterol, asthma, epilepsy, mental
illness, and heart problems). Sixty-three pharmaceuticals were detected in the city’s
watersheds.

Treated drinking water serving approximately 18.5 million people contained anti-epileptic
and anti-anxiety meds in southern California.

Treated drinking water in northern New Jersey serving approximately 850,000 people
contained metabolized angina medicine and mood-stabilizers.

Sex hormones have been detected in San Francisco drinking water.

Steroid levels downstream of Nebraska feedlots were four times greater than upstream of
the feedlots.
4.0 Effects of Pharmaceuticals in the Environment
Pharmaceuticals in the environment have the potential to affect both humans and the environment.
The risks to humans are largely unknown because the concentrations of individual contaminants of
concern are so low. In addition, it is unknown how the combination of multiple PPCPs ingested
over a long period of time will affect people. Although many postulate that the effect on healthy
adults will be minimal due to the limited concentrations, there are concerns about sensitive groups
such as the elderly, people with severe allergies, people with health problems, and fetal exposure to
PPCPs that expectant mothers would typically avoid.
Although the effects on humans are still largely unknown, there have been documented negative
effects on of PPCPs on wildlife.
Pharmaceuticals have decimated the vulture population in Southeast Asia. In the early 1990s,
farmers used the anti-inflammatory drug diclofenac to relieve inflammation that could impair
animal’s ability to produce milk or plow fields. The dead cows were sent to special dumps where
vultures ate their carcasses. Between 2000 and 2007, the South Asian vulture populations decreased
by 40% each year due to renal failure caused by the diclofenac. Although the drug is now banned;
the drug still exists in some livestock, and a replacement anti-inflammatory has shown to have the
same effect on the vultures. Although the diclofenac was not released to a water body, it is an
example of how PPCPs can have a profound negative effect on wildlife.
Estrogens in water bodies have shown to cause excess feminization in fish and throw off male to
female ratio. Studies in fish upstream and downstream from wastewater treatment plants have
found more female and intersex fish downstream from plants (most likely due to increased levels of
estrogens in downstream water). Other studies have shown antidepressant medications concentrated
in the brain tissue of fish downstream from wastewater treatment plants.
Another concern regarding the increase of antibiotics in the environment is antibiotic-resistant
pathogens. Bacteria share genes across species; increased drug resistance in one species can spread to
another. Drug-resistant bacteria populations are much more prevalent in areas where antibiotics are
heavily used, such as in dairy farms and in lakes that receive effluents from hospitals.
5.0 Current Treatment Technologies
Current wastewater treatment plants are not designed to address pharmaceuticals. Currently, there
are no municipal sewage treatment plants that are engineered specifically for PPCP removal.
POTWs were designed for conventional pollutants such as suspended solids, and biodegradable
organic compounds. The conventional treatment can reduce the concentrations of certain PPCPs,
but some are completely resistant to traditional treatment. .
Some drugs, such as ibuprofen and naproxen, can be reduced by about 90% in conventional
treatment technologies. Other drugs, such as cholesterol fighters, tranquilizers, anti-epileptics resist
modern drinking water and water treatment processes. Although sewage treatment may remove
certain pharmaceuticals from water, the pharmaceuticals end up in the sludge. Since sludge is
frequently used as fertilizer, the pharmaceuticals still have the opportunity to leach into the
environment.
As of 2007, over 100 individual PPCPs have been identified in environmental samples and drinking
water. The number of PPCPs available for human consumption is growing. Prior to selling new
drugs, pharmaceutical companies do not investigate the potential for downstream effects.
6.0 How to Address the Issues
The risks of PPCPs to wildlife have started to be documented, but the risks to humans are still
unknown. Over 100 PPCPs have been detected in environmental and drinking water samples, and
the quantity has the potential to increase.
To reduce the quantities of PPCPs released to the environment from the public, there are several
steps that can be taken. The government can provide education to prevent people from disposing of
unused medication down the toilet. In addition, municipalities or manufacturers can sponsor drug
take-back programs to provide residents a place to bring unused and unwanted education.
Partnerships with health care facilities such as long care facilities will be required to reduce the
quantities these facilities flush. Due to the complex maze of regulations that currently exist; flushing
medications may be a facilities only option. Allowing facilities to easily return medications to the
manufacturer or to a reverse distributor may greatly decrease the quantities that are flushed.
To reduce the quantity of pharmaceuticals people and livestock excrete through urine and feces,
doctors and veterinarians can try to prescribe dosages based on people’s specific body chemistry and
body weight instead of a generic quantity. Many farms overmedicate on purpose to ensure livestock
don’t get sick. In addition, manufacturers can try to design medications that are absorbed by bodies
more efficiently and will break down easily once excreted. This may quicken the expiration date of
medications or require refrigeration of medications; which will decrease convenience that people
have come to expect.
To get a better idea of the quantities and locations of PPCPs in water, additional monitoring of
water supplies is recommended to determine if additional treatment methods are necessary.
. 7.0 Conclusions
The presence of PPCPs in water is a relatively new area of concern, and the full effects on people
and the environment is still unknown. Although potential consequences are not fully understood,
there are still steps people can take to reduce the quantities of PPCPs that are released into the
environment. This is a complex problem that will require the participation of governments,
businesses, residents, and PPCP manufacturers.
References
Drugs in the Water. Harvard Health Publication: Harvard Medical School.
http://www.health.harvard.edu/newsletters/Harvard_Health_Letter/2011/June/drugs-in-the-water Published June
2011, Accessed November 24, 2013.
Donn, Jeff, Mendoza, Martha, and Pritchard, Justin. Pharmaceuticals lurking in U.S. drinking water. Associated Press,
March 10, 2008.
Health Care Industry Unused Pharmaceuticals Detailed Study 2007-2009 Data Collection and Outreach. US
Environmental Protection Agency, September 22, 2009.
Hernando, M. Dolores, Gomez, Jose, Aquera, Ana, and Fernandez-Alba, Amadeo R. LC-MS Analysis of Basic
Pharmaceuticals (beta-blockers and anti-ulcer agents) in wastewater and surface water. Trends in Analytical Chemistry,
Vol. 26, No.6, 2007.
Kan, Usman and Nicell, Jim A. Refined Sewer Epidemiology Mass Balances and their application to heroin, cocaine, and
ecstasy. Environment International 37 (2011) 1236-1252.
Konkel, Lindsey. Flying the coop: antibiotic resistance spreads to birds, other wildlife. Environmental Health News,
November 5, 2013.
Memorandum of Understanding on sustainability of Federal Collaboration on Pharmaceuticals in Drinking Water.
Between the EPA Office of Water, USDA Agricultural Research Service, FDA, and the USGS.
Occurrence of Contaminants of Emerging Concern in Wastewater from Nine Publicly Owned Treatment Works. US
Environmental Protection Agency, August 2009.
Onsite Sewage Treatment Program. University of Minnesota http://septic.umn.edu/factsheets/medicationsandseptics/,
accessed November 24, 2013.
Pharmaceuticals and Personal Care Products (PPCPS), http://www.epa.gov/ppcp/faq.html, accessed November 11,
2013.
Pilot study of pharmaceuticals and personal care products in fish tissue. US Environmental Protection Agency.
http://water.epa.gov/scitech/swguidance/ppcp/fish-tissue.cfm, Accessed 11/10/13.
Pilot Study of Pharmaceuticals and Personal Care Products in Fish Tissue. US EPA, March 2009.
Publicly Owned Treatment Works (POTW) Wastewater Sampling Study.
Research in Action: Pharmaceuticals. USEPA, http://www.epa.gov/eerd/research/pharmaceuticals.html, accessed
11/10/13.
Schwab, Bradley W. et al. Human Pharmaceuticals in US Surface waters: A Human Health Risk Assessment. Regulatory
Toxicology and Pharmacology 42(2005) 296-312.
Shah, Sonia. As Pharmaceutical Use Soars, Drugs Taint Water & Wildlife. Yale Environment 36. Accessed at
http://e360.yale.edu/feature/as_pharmaceutical_use_soars_drugs_taint_water_and_wildlife/2263/Posted April 15,
2010.
Unused Pharmaceuticals in the Health Care Industry: Interim Report. US Environmental Protection Agency, August
2008.
Download