Surface Water Contaminants
Are pharmaceuticals and personal care products really a threat?
In 1974, Congress passed the original Safe Drinking Water Act (SDWA). This bill provided regulation of public water supplies in the US; it was amended in 1986 and 1996. The SDWA authorized the EPA to set national standards to protect the public against both naturally occurring and manmade contaminants that may be present in our drinking water.
The SDWA regulations apply to each of the more than 170,000 public water systems in the US. It has long been known that some of the potential contaminants include animal wastes, chemicals improperly disposed of, pesticides, various wastes injected deep underground, and naturally occurring substances that may pose a threat to human health.
As the EPA states, “To ensure that drinking water is safe, SDWA sets up multiple barriers against pollution. These barriers include source water protection, treatment, distribution system integrity, and public information. Public water systems are responsible for ensuring that contaminants in tap water do not exceed the standards.”
In recent years, much concern has been raised about the ominous appearance of pharmaceuticals and personal care products (PPCPs) in the public water supply. The American Water Works Association (AWWA) explains that “PPCPs are a group of compounds consisting of human and veterinary drugs (prescription or over the counter) and consumer products, such as fragrance, lotions, sunscreens, house cleaning products, and others. These compounds have been detected in trace amounts in surface water, drinking water and wastewater effluent sampling conducted in both Europe and the US” (AWWA 2009).
Most likely, the level of PPCP contaminants has been increasing, as the production of PPCPs has increased. Certainly our ability to detect them has improved to the point now where elements can be measured in the parts-per-trillion range. For comparison, many drinking water standards are set in parts per billion.
Source of Contaminants
There are a number of sources for PPCPs in surface water and in the public drinking supply. The EPA states, “The discharge of pharmaceuticals and synthesis materials and by-products from manufacturing are already well defined and controlled.” A large percentage of PPCPs in the environment appears to come from unmetabolized pharmaceuticals in human waste and from other products disposed of by flushing or by being placed in the trash.
Other sources may include septic tank leaks, sewer line breaks and leaks, agricultural runoff, other stormwater runoff, and illegal discharges, according to the New Mexico conservation group Amigos Bravos.
Some of these items enter wastewater treatment plants, but many PPCPs are not among the contaminants that these plants are designed to detect and remove. PPCPs can also be found in sanitary sewers and in combined sewer overflows.
Ultimately, the EPA explains, “PPCPs are found where people or animals are treated with drugs and people use personal care products. PPCPs are found in any water body influenced by raw or treated sewage, including rivers, streams, ground water, coastal marine environments, and many drinking water sources. PPCPs have been identified in most places sampled.”
Studies Confirm PPCPs in Public Water Supplies
In 1999 and 2000, the Toxic Substances Hydrology Program of the US Geological Survey (USGS) found that “A broad range of chemicals found in residential, industrial, and agricultural wastewaters commonly occurs in mixtures at low concentrations downstream from areas of intense urbanization and animal production. The chemicals include human and veterinary drugs (including antibiotics), natural and synthetic hormones, detergent metabolites, plasticizers, insecticides, and fire retardants. One or more of these chemicals were found in 80% of the streams sampled. Half of the streams contained seven or more of these chemicals” (USGS 2002). In most cases, the USGS reports, these substances were found in concentrations less than one part per billion.
More recently, in a report released in March 2008, an extensive five-month study conducted by the Associated Press (AP) found that “A vast array of pharmaceuticals—including antibiotics, anti-convulsants, mood stabilizers and sex hormones—have been found in the drinking water supplies of at least 41 million Americans” (Donn et al. 2008).
The AP tested drinking water in 24 major metropolitan areas, but researched water suppliers in all 50 states. Its report noted that the federal government does not require any testing for pharmaceuticals, and many water suppliers generally screened for only one or two pharmaceuticals.
The AP report also noted, “In the United States, the problem isn’t confined to surface waters. Pharmaceuticals also permeate aquifers deep underground, source of 40% of the nation’s water supply. Federal scientists who drew water in 24 states from aquifers near contaminant sources such as landfills and animal feed lots found miniscule levels of hormones, antibiotics, and other drugs.”
In another study, from the summer of 2009, Amigos Bravos released the results of a water-quality study that examined various locations along the Rio Grande River. In addition to organic solids, the organization detected seven different PPCPs, including acetaminophen, a tranquilizer, caffeine, an antibiotic, and an anti-seizure medication.
Clearly, pharmaceuticals, pesticides, and other contaminants are present in many, if not all, public water supplies, albeit usually in minute quantities. The primary question is what effect these elements have on the environment, on aquatic life, and ultimately, on human health.
Effect on the Environment
G. Fred Lee, president of G. Fred Lee and Associates in El Macero, CA, has worked on numerous Superfund sites, as well as other hazardous chemical sites, and has written extensively on the topic of contaminants in groundwater and surface water.
Regarding the presence of PPCPs and pesticides in stormwater runoff, Lee notes that stormwater best management practices (BMPs) are typically used for water-quality treatment of runoff. “These aren’t designed to remove anything more than particulates. Typically, many of the pharmaceuticals and pesticides will pass right through these. We’re not treating for that at all. If the BMP involves a situation in which stormwater is injected into groundwater, then you have the potential to remove them from surface waters, but you have the potential to move them into groundwater. More and more of the stormwater runoff treatment systems involving infiltration of the stormwater into the groundwater systems.”
Some of the best environments for infiltrating stormwater present a possible hazard for groundwater. Citing a study done in Long Island, which has sandy soils, Lee notes, “Sandy situations are great for allowing a lot of infiltration, but they have very little ability to prevent pollutant transport.”
Another concern is the roughly 7,000,000 tons of biosolids produced annually by the nation’s wastewater treatment plants. The USGS notes that because these biosolids are rich in plant nutrients, about 50% of this production is sold as fertilizer for plants. A 2006 paper in Environmental Science and Technology reported that USGS scientists identified dozens of organic chemicals in the biosolids they tested, including what they described as “compounds that are pharmaceutically and hormonally active” (Kinney et al. 2006a).
USGS scientists produced a separate 2006 article in Environmental Toxicology and Chemistry, looking at soil irrigated with treated wastewater (Kinney et al. 2006b). In this study, it was found that “Pharmaceuticals in wastewater used for irrigation persist in soil for several months after the irrigation stopped for the season.” Examining soil cores over a period of time, the scientists concluded that not only did the soil retain pharmaceuticals, but there was evidence that some pharmaceuticals were transported to greater depths within the soil.
Effect on Aquatic Life
The EPA comments, regarding PPCPs and other water contaminants, that “Exposure risks for aquatic organisms are much larger than those for humans.” It lists the following increased risk
- Continual exposure
- Multi-generational exposure
- Exposure to higher concentrations of PPCPs in untreated water
- Possible low-dose effects
Specifically, the March 2008 AP report referenced above alludes to various mutations in fish physiology that are presumed to be effects from pharmaceuticals in the water.
Lee adds that it is well established that pharmaceuticals and pesticides bioaccumulate in fish, and that, in fact, this phenomenon is typically undermeasured. “What we typically find, unfortunately, is that a number of people look at drinking water MCL [maximum concentration level] as the criteria to judge stormwater runoff, but that makes no sense at all. If you have fish there, and you have chemicals like PCBs, DDT, or mercury in the runoff, then they will bioaccumulate. We do know that the pharmaceuticals are causing impaired fish reproduction and changes in characteristics of fish in surface water.”
In a November 2009 paper, Lee noted, “Limited attention is typically given in stormwater monitoring/remediation programs to monitoring for ‘toxicity’ that could be caused by chemicals that are not measured; that are toxic at levels below analytical limits; that are not recognized or identified as pollutants; or that in combination with other chemicals can cause toxicity, to aquatic life in the watercolumn and/or sediments of the receiving water.
“An example of ramifications of these inadequacies in typical stormwater monitoring is seen in experience with organophosphorus and pyrethroid-based pesticides that are used in urban and/or agricultural areas. The widespread presence of organophosphorus and pyrethroid-based pesticides causes stormwater runoff from many areas to be toxic to some forms of aquatic life, especially zooplankton. This toxicity is a violation of the Clean Water Act requirements for the control of toxics in toxic amounts.
“Concentrations of these chemicals in water at levels that are not believed to cause unaccepted human health impact or aquatic life toxicity, can bioaccumulate in aquatic organisms to levels that render the organisms unsuitable for use as food for people and hazardous to higher trophic-level organisms especially fish-eating birds and animals” (Lee and Jones-Lee 2009).
Michael Jensen, of the New Mexico-based Amigos Bravos organization notes, “The science seems quite clear that PPCPs in rivers, streams, and lakes cause harm to aquatic life, even at the very low levels (nanograms or parts per trillion) at which they are typically found. It may be the case that endocrine disrupting compounds have the most harm and this may be because animals—and humans—are designed to respond to low levels of these as part of their development and functioning.”
The EPA’s Dr. Mitch Kostich is confident that the threat to humans from PPCPs is “very remote,” but says, “For aquatic life and other non-human organisms, the story is not as clear. The rates of exposure for some organisms are potentially higher than for humans. In addition, although the safety profile of the vast majority of pharmaceuticals is well established in humans (perhaps more so than for any other class of contaminants, except radionuclides), similar dose response data is almost completely lacking in ecologically important organisms such as fish, birds, insects, worms, plants, fungi, etc.
“The limited data available suggests that a small minority of pharmaceuticals may pose some environmental threat. The strongest suggestions for the possibility of harm come from studies on the reproductive effects of contraceptives at ecologically relevant concentrations in fish, and kidney damage in vultures consuming carcasses of domesticated cattle previously treated with the anti-inflammatory drug diclofenac. Most studies on the toxicology of other pharmaceuticals in non-humans suggest that effects can only be discerned at concentrations of pharmaceutical much higher than those likely to be encountered in the environment.”
Effect on Human Health
Nearly all parties agree that little is known about the human health effects of pharmaceuticals and other contaminants in the water supply.
Jensen states, “Laboratory experiments on animals and on human tissues show impacts from PPCPs and scientists are beginning to theorize on the sorts of mechanisms that might be at work, including immune system responses and chronic low-dose exposure. The idea that chronic low-dose exposure could be harmful is outside the existing dose limit paradigm, which looks at acute high dose exposure.
“However,” he adds, “the science seems to be trending toward an impact on human health from PPCPs, added to the documented harm to aquatic life, and some speculation on impacts to crops grown in shallow groundwater with traces of PPCPs. It is a problem that needs more information in order to develop the best responses.”
In a paper titled “Unrecognized Environmental Pollutants,” Lee quoted Dr. K. Hooper of the Hazardous Materials Laboratory, California EPA Department of Toxic Substances Control: “Over the past 25 years, tens of thousands of new chemicals are introduced into commerce after evaluation by USEPA. Few (100–200) of the 85,000 chemicals presently in commerce are regulated. We have reasons to believe that a much larger number than 200 adversely affect human health and the environment” (Lee and Jones-Lee 2005).
Dr. Shane Snyder of the Southern Nevada Water Authority has a differing view. In a 2008 statement before a Senate subcommittee examining potential risks of pharmaceuticals in the US water supply, he noted that he has conducted research in this field for nearly 15 years. He told the subcommittee:
“The few pharmaceuticals we did detect in US drinking waters occurred at unfathomably low concentrations. To illustrate that point, consider this: If our study had been constrained by the ability to find these compounds at parts-per-billion levels instead of delving into the parts-per-trillion range, none of them—not a single one—would have been found…. Are we going to make decisions based upon our ability to find contaminants, or based upon
protection of public health?
“Decades ago, we could only detect contaminants at parts per million levels,” his statement continued. “Years ago, we advanced to parts per billion. We are now able to detect compounds at the parts-per-trillion level, and are breaching the parts-per-quadrillion boundary in some cases. The truth is that the concentrations of pharmaceuticals found in water supplies are millions of times lower than a medical dose.”
The American Water Works Association echoes Snyder’s thoughts. In response to the March 2008 AP report demonstrating the widespread presence of pharmaceuticals in the nation’s water, Tom Curtis, deputy executive director of the AWWA, wrote:
“Research throughout the world has not demonstrated an impact on human health from pharmaceuticals in drinking water at the trace levels at which they have been found. People regularly consume or expose themselves to products containing these compounds in much higher concentrations through medicines, food and beverage, and other sources.”
Yet, while no definitive proof appears to exist confirming a detrimental effect on human health from PPCPs and other contaminants, Lee concludes, “Based on the vast array of chemicals that are used in commerce, many of which are or could be introduced into aquatic systems from wastewater and stormwater runoff, it is likely that many other chemicals will be discovered in the future that are a threat to public health or aquatic ecosystems.”
Indeed, the EPA warns, “Some people may be more vulnerable to contaminants in drinking water than the general population. People with severely compromised immune systems, such as people with cancer undergoing chemotherapy, people who have undergone organ transplants, people with HIV/AIDS or other immune system disorders, some elderly, and infants can be particularly at risk from infections. These people should seek advice about drinking water from their health care providers.”
However, these health care providers may well be no better informed about the effect of PPCPs in the environment than the general population.
What Is Being Done, and What Needs to Be Done?
Just as there is a wide array of opinions regarding the effect of these contaminants on human health, similarly there is no shortage of suggestions about what actions should be taken at the
The American Water Works Association states, “The water community is committed to protecting public health. Water professionals are examining the occurrence of PPCPs in drinking water supplies and are paying close attention to health effects research in this area. Water professionals also are researching the effectiveness of current treatment techniques on removal of PPCPs and other organic compounds. Because of the wide array of chemical structures and properties associated with PPCPs, no one single treatment can remove them all” (AWWA 2009).
The EPA, for its part, maintains a program known as the Contaminant Candidate List (CCL), which identifies contaminants in public drinking water that merit further study. The CCL released in September 2009 contained pharmaceutical compounds for the first time, consisting of one antibiotic (erythromycin) and nine hormones.
From the EPA Office of Water comes the following statement:
“The EPA is committed to investigating the topic of pharmaceuticals in the environment and developing strategies to protect public and environmental health. Our four-pronged approach for addressing the problem is aimed at strengthening scientific knowledge; improving public understanding; building partnerships for stewardship; and taking regulatory action where appropriate. These efforts include studies into the occurrence of PPCP contaminants in fish tissue, wastewater, drinking water and biosolids, and also includes development of new analytical methods. Other projects in this area include studying the health effects of PPCPs, working with the health care industry to manage unused pharmaceuticals, and reaching out to external organizations like the National Academy of Science and the World Health Organization to better understand and evaluate potential risks and risk assessment methods.”
The USGS is working to develop new techniques to reliably measure the presence of a variety of pharmaceuticals, fungicides, and insecticides, intending to provide information on new and understudied contaminants to water-resource managers, regulators, and the public.
The Resource Conservation and Recovery Act was enacted in 1976 and regulates the management and disposal of hazardous pharmaceutical wastes, impacting both manufacturers and the health care industry.
At present, there is no regulation of discarded household pharmaceutical waste, although the EPA has urged the public to participate in pharmaceutical “take-back” programs where they exist.
Others urge that a great deal more can and should be done.
Jensen has been frustrated by “the resistance to discussing PPCPs by water providers—including our WUA [Albuquerque Bernalillo County Water Utility Authority], which has consistently denied [until recently] that PPCPs are in the river or its wastewater or the drinking water.”
Asked if other pollutants such as heavy metals or even sediment might pose a greater threat than PPCPs, Jensen says, “It is hard to say that some contaminants are ‘more serious’ given the current limitations in our understanding of PPCPs, the lack of totally effective treatment processes, and the denial that often exists—at least in public—among water providers and wastewater treatment operators. But, yes, there are serious threats to our waters and the public health: acid leaching from mines, fertilizer and herbicide and pesticide runoff from agricultural operations, development of antibiotic-resistant strains due to overuse of antibiotics in CAFOs [concentrated animal feeding operations], E. coli and other pathogens cropping up everywhere, as well as metals and sediments.”
However, Jensen is encouraged by trends he sees. “A lot is being done already. The EPA and other agencies are conducting better monitoring, developing new analytical methods that are able to reliably report results at the nanograms level, trying to determine which PPCPs are most harmful with a possible view towards standards, and investigating better treatment methods. A lot more could be done in all these areas and will take a collaborative effort by drug manufacturers, water utilities, private and public research facilities, and state and federal agencies. We urge people to contact their congressional delegation and ask them to press the agencies to do more and to help fund that effort. The media has done a good job of making the issue more visible.”
He adds, “The Associated Press stories in early 2008 showed both that many municipalities aren’t monitoring for PPCPs, but that among those that do, they are widespread. The local media here has covered the issue repeatedly—in part because Amigos Bravos has made an issue of it [and been accused sometimes of being ‘sensational’]. Municipalities need to set up drug take-back programs, although this will likely require state and federal rule changes allowing people to turn in certain classes of drugs that currently are prohibited from transfer by the named patient to a third party. This past summer, Rio Rancho held a one-day resident drug take-back program, but had to get the police and the New Mexico Environment Department involved. Perhaps a better method might be to allow designated pharmacies to take back expired or unused medications and dispose of them through licensed and regulated facilities. People need to be educated on the proper way to dispose of pharmaceuticals now—that is, not down the drain but in the trash, mixed with something unappealing—although some law enforcement representatives I have spoken with still think that some dangerous but popular prescription medications should be sent down the drain so people can’t find them in the trash.”
Fred Lee says the technology already exists to modify wastewater treatment plants to more effectively remove pharmaceuticals and other contaminants. “We know how to do it. It’s just a matter of who will pay for it. We can treat wastewater to remove these chemicals, but that would increase your sewer bill significantly. It’s costly.”
He raises another issue when it comes to treating urban stormwater runoff. “The problem with treating urban stormwater runoff is that you get such very high flows over short periods of time. So you wind up with a situation where you have to have a massive treatment works just to collect and treat the high flows. It would sit idle most of the time, but then you have a one-inch storm over a 24-hour period. In Alameda County in the San Francisco Bay area, the head of the stormwater program said that for them to collect a one-inch storm, which is not an atypical storm, over a 24-hour period, it would take 10 Oakland Coliseums in size to hold all this water.
“The problem is you have such massive flows,” he continues. “Conventional treatment ideas—like we do with sewage, where the flows are pretty steady—don’t apply. There was a study several years ago where actual treatment of stormwater runoff, the cost to the public served by the storm sewers, is on the order of dollars per person per day. It’s very high, up to 10 dollars per person per day. We’re not prepared to even begin to address that issue.”
Rather, he says, “Environmental groups have been trying for years to get the USEPA to enforce its own regulations for NPDES-permitted discharges—stormwater comes under an NPDES permit—to enforce this regulation with respect to controlling violations of water-quality standards. The EPA has not, nor will it, willingly do this, because of the cost. So we have these regulations in effect, which are not being enforced, because of the very high cost. And it’s understandable. The public won’t pay for this.”
Lee does suggest a change in the manner in which stormwater runoff water-quality monitoring is conducted. Lamenting the “grossly inadequate” present system, he has been urging monitoring agencies to increase both the frequency and the duration of monitoring to more accurately measure the presence and quantity of hazardous chemicals.
Former Centers for Disease Control and Prevention director Dr. Julie Gerberding presented somewhat of a consensus view when she stated, “One of the great things about the scientists at CDC and the scientists at EPA and elsewhere is that they’ve been able to develop instruments that can detect exquisite quantities of chemicals in water and other materials. So we can find the chemicals, but they’re at extremely low levels. We have not been able to identify any direct health effects of those very low-level exposures so far. But of course there’s a reason to continue to look, to measure, and to do more science to try to get to the bottom of the issue” (AWWA 2009).
Steve Goldberg writes on issues related to erosion control and the environment.