Pervasive and Persistent: Constituents of Growing Concern
January/February 2011
Introduction
Is the water consumed by people everyday safe to drink or should there be concern about unregulated contaminants, many of which are the remnants of commonly used pharmaceutical and personal care products?
The question has moved from the science community to the realm of mainstream conversation as it relates to water quality regulations. While new regulations are probably far from completion, the issue has the attention of scientists, regulators and water agency personnel.
“People want to know if we are going to regulate these,” said Bruce Macler, regional toxicologist with the U.S. Environmental Protection Agency (EPA). “We use a huge amount of organic chemicals [and] my job is to pay attention to these things, not ignore them.”
Macler and other scientists spoke about constituents of emerging concern (CEC) at a November water quality and regulatory conference in Ontario, Calif.
Such constituents include pharmaceuticals and personal care products (PPCPs). They enter water through the use of items such as soap, shampoo and sunscreen, improper disposal of unused medicines, excretion of unabsorbed medications and accidental spills. Most are treated to near-zero detection limits but the threads of others elude the process and remain in drinking water sources.
CECs are changing the focus of water quality monitoring to some degree because most programs focus only on chemicals upon which there is sufficient scientific evidence to indicate they may pose an increased risk to human health and aquatic life at high levels.
“We don’t know what they may be doing to us at these levels but at this point we don’t have any reason to believe they are having an effect,” Macler said. “It’s probably not much or we would have seen something already.”
According to a May 2010 report, Source, Fate, and Transport of Endocrine Disruptors, Pharmaceuticals, and Personal Care Products in Drinking Water Sources in California, trace levels of CECs were found in water at 32 sampling locations in the Delta, State Water Project facilities, Colorado River and Santa Ana River. The report, published by the National Water Research Institute (NWRI), said “the general consensus is that there is no evidence of human health risk from low levels of the commonly detected [endocrine disruptors] and PPCPs in drinking water or drinking water supplies. Nonetheless, more toxicologi¬cal studies of PPCPs are needed.”
The number and amount of chemicals in use today is voluminous. More than 80,000 chemicals are currently approved for use under federal law and each day 42 billion pounds are pro¬duced in or imported into the United States, according to the State Water Resources Control Board (State Water Board).
Thousands of unregulated chemicals in water are being sorted through in an attempt to see if and where a threat to public health exists and how to best approach it. Some of the unknown contaminants are endocrine disruptors with the ability to interfere with the body’s distribution of hormones and current regulations “may not be reducing these risks,” Macler said.
The focus on CEC has been assisted by the ability of laboratories to detect them at heretofore untraceable levels in water and the emphasis on recycled water use. Last June, a panel of scientific experts commissioned by the State Water Board to recommend modifications to its Recycled Water Policy reported that “many CECs are potentially present in recycled water, but the detection of many of these chemicals is so recent that robust methods for their quantification and toxicological data for interpreting potential human or ecosystem health effects are unavailable.”
Because of the uncertainty, the State Water Board believes CECs should be monitored according to their potential threat to human health, such as endocrine disruption. The agency is moving from a “somewhat scattered approach” toward a science-based framework that puts it in the position for a “rational reason” behind which CECs are monitored and the required action at certain detection levels, said Jonathan Bishop, chief deputy director.
“The point of the Recycled Water Policy was to help incentivize the use of recycled water and part of that was trying to address concerns that CECs are a potential problem,” Bishop said. “We are trying to have a rational way of looking at it so we are not impeding its use because we need the resource and we need to use it responsibly.”
Agencies that recycle water are closely involved with the regulatory development, seeking to ensure that new rules to monitor CECs are put forward in a uniform, cost-effective manner using the best science. Dave Smith, managing director with WateReuse California, said the panel’s CEC monitoring recommendations meet his organization’s criteria. Monitoring requirements for existing groundwater recharge projects are quite different from one another and “some of this variability is based on inconsistent thinking and criteria so we are suggesting those monitoring programs should be reviewed and not just allowed to continue.”
Despite appearing in infinitesimal amounts, CECs in water do catch the public’s attention. An Associated Press report in 2008 received national coverage with the revelation that CECs were in the drinking water of 24 major metropolitan areas. Among the drugs detected were antibiotics, anti-convulsants, caffeine, anti-depressants and veterinary medicines. Triclosan, a common antimicrobial agent that is suspected to have adverse effects on aquatic life, is pervasive because it eludes wastewater treatment and is highly stable for long periods of time.
Subsequent polling revealed a substantial degree of concern by respon¬dents, many of whom have switched to bottled water.
The AP report “caused quite a stir,” even though the revelations were things experts already knew, said William Cooper, a professor at the University of California, Irvine’s Urban Water Research Center. The existence of pharmaceuticals in wastewater in low concentrations reflects the con¬tinuous and growing use by people for a number of conditions, from high cholesterol to erectile dysfunction. “It’s a huge market – $240 billion,” he said. “Pretreatment is not an option – we are all the point source.”
The use (some would say overuse) of antimicrobials has the unintended result of creating “super bugs,” bacteria that have adapted and become much more resistant, Cooper said.
Assuring people that their water is safe to drink becomes more challenging with the release of each new report on CECs. Those studying the issue say it is to some degree driven by external influences. “Public perception is very powerful,” said Richard Pleus, managing director at Intertox, a scientific consulting and research firm in Seattle. “Consumers are understandably concerned with any amount of a CEC that may appear in drinking water. However, those same chemicals are necessary for everyday life. The issue is one of dose or rather when does a chemical cease to be beneficial and become toxic.”
With improved drinking water quality, the question becomes: what is the remaining risk to human health from unregulated contaminants? In lieu of a yes or no answer, Macler framed the question differently, saying “maybe the glass isn’t half empty or half full, but too large,” and that maybe federal regulations have already addressed the significant drinking water risks.
“For all the attention, regulations, treatment and costs, we don’t know the extent to which we are making a difference,” he said. “We don’t know much about waterborne disease or the large scale public health risks from contaminated drinking water. We have no direct means to track changes in health outcomes from our regulations. The extrapolations from controlled animal studies to impacts on humans in their day-to-day world are hard to validate. Since our risk assessment methods are conservative, we are likely overestimating the annual health impacts from drinking water.”
Nonetheless, more investigations are focusing on where CECs are found, the type of chemicals detected and the connections, if any, to human health. From the ecological side, scientists know that some CECs at part-per-trillion levels can impact aquatic species such as fish and frogs through altered hormone levels and decreased reproduction rates. Keith Maruya, principal scientist with the Southern California Coastal Water Research Project, said water quality officials are focusing on the link between CECs in the environment, their effects and “what’s the smart thing to do.”
“We know they are out there and we are aware there can be effects at low levels, but the bottom line is we have not seen a link to [CECs] and fish populations crashing in the ocean,” he said.
Scientists are working to put together priority lists of CECs based on their existence and possible health impacts. The task is not easy and must incorporate lower detection levels, determining the synergistic effects of different chemicals and accounting for the new products coming on the market. “We have to identify toxic levels based on scientific research and medical studies,” Pleus said.
The scientific inquiry into CECs coincides with efforts at EPA to de¬velop a “new vision” for drinking water regulations that includes contaminant grouping, Macler said. The agency compiles a “contaminant candidate list” that includes many CECs and will have drinking water utilities gather data. But there are no plans to pursue CECs in a regulatory manner.
“EPA’s current take is that there is no evidence that pharmaceuticals and personal care products in the environment cause human health effects,” Macler said. “The levels in the environment are so low relative to the levels known to have clinical effects, that no effects are predicted.”
This issue of Western Water, based on presentation at the November 3-4, 2010 Water Quality Conference in Ontario, Calif., looks at CECs – what is known, what is yet to be determined and the potential regulatory impacts on drinking water quality.
Click here to purchase a copy of the complete article.
Editor’s Desk
Famous Authors and their Water Quotes or Misquotes…
Recently, two literary giants have been quoted in the debate over California water issues: Samuel Taylor Coleridge and Mark Twain. In the case of both authors, the full story over their water quotes is an amusing one.
Several members of Congress in recent years have quoted portions of Coleridge’s poem “The Rime of the Ancient Mariner” in their arguments for and against environmental legislation. School children all know the quote, “Water, water everywhere but not a drop to drink…” Perhaps you, like me, didn’t quite remember the entire poem. It tells the story of a mariner who uses his crossbow to shoot an albatross that had been guiding the ship through a dangerous passage. This fatal action sealed the crew’s fate and they were adrift in a windless sea. As Coleridge said,
“Water, water everywhere,
And all the boards did shrink,
Water, water, everywhere,
Nor any drop to drink.”
Some critics of Delta pumping cutbacks quote Coleridge to show that there is an abundance of water but not enough is going to farms and cities due to judicial interpretations of the federal Endangered Species Act. Others use the quote to show that endangered species shouldn’t be harmed or society – like the mariner – will pay the consequences. Mike Doyle of McClatchy Newspapers recently wrote about politicians quoting the Coleridge poem to make varying points. He wrote that Coleridge “could never have guessed how he’d be conscripted into California’s partisan water wars.”
I contacted Mike to let him know what I knew about another famous quote. There is a familiar quote attributed to Mark Twain, “Whiskey is for drinking, but water is for fighting.” The whiskey quote has been around as long as I have been in the water world but I recall in earlier days it was picked up by a few people with the comment, “I think it was Mark Twain who said…” Later it became set in stone that Mark Twain said it. That’s why years ago I called the Mark Twain Library to verify the quote. The librarian said the quote has never been found in any of Twain’s written works. The librarian told me it may have been in one of his speeches but they had no record of it. Recently I pulled up the site www.twainquotes.com and the site notes, “This quote has been attributed to Mark Twain, but until the attribution can be verified, the quote should not be regarded as authentic.”
So what is the point of exploring the meanings and origins of poems and quotes? I think it makes us more precise in our use of language and helps us use lit¬erary analogies and quotes correctly – to the best advantage. One thing I believe, people will still quote Mark Twain and use the whiskey quote because the fighting over water will continue – and it is a great quote! However, maybe they will pref-ace the quote by saying, “Mark Twain should have said…!”
In the News
Scientists Urge Lower Public Health Goal for Perchlorate
Prompted by new information about the effects of the chemical perchlorate on infants, state officials are proposing to lower the public health goal in drinking water to 1 part per billion (ppb). The U.S. Environmental Protection Agency on Feb. 2 announced plans to regulate perchlorate under the Safe Drinking Water Act.
One ppb is roughly equivalent to one teaspoon in an Olympic-size swimming pool.
A public health goal (PHG) is not an enforceable regulatory standard but an advisory for the Department of Public Health in reviewing the existing state drinking water standard, or maximum contaminant level (MCL), for perchlorate. The current MCL is 6 ppb. The department must set its drinking water standards as close to the corresponding PHGs as is economically and technically feasible.
“New research about perchlorate’s potential to affect the health of California babies has led [our] scien¬tists to develop this revised public health goal for drinking water,” said Joan Denton, director of the Office of Environmental Health Hazard Assessment (OEHHA). “The revised goal reflects infants’ enhanced susceptibility to the health effects of this chemical.”
Perchlorate is a chemical that can occur naturally and also may be released by fireworks, rocket fuel and various industrial processes. Exposure to perchlorate can affect infant brain development, growth and other key body functions. Perchlorate is known to damage the thyroid’s ability to take in and process iodide, which is a nutrient essential to brain development, growth, heart function and other systems. The draft PHG is based on data on how much water infants consume per pound of body weight.
Public health advocates said a lower MCL is long overdue because of the threat perchlorate poses to sensitive populations.
“The special susceptibility of young infants is the main reason why the new perchlorate PHG is lower than the last one,” said Gina Solomon with the Natural Resources Defense Council. “The prior regulation neglected to consider the breastfed infant, and also the significant water consumption of bottle-fed infants. In addition, people with nutritional iodine deficiencies are at much greater risk of adverse effects from perchlorate. That’s why getting enough dietary iodine – from seafood or, less ideally, from iodized salt – is so important for pregnant women and children.”
Those responsible for cleanup actions believe the 6 ppb standard is justifiably safe and that lowering the number could threaten supplies and raise water rates without appreciable benefit. “Public health protection is of the utmost importance and the science on perchlorate has been abundantly clear for more than five decades: trace levels found in the environment do not pose a threat to public health,” the Perchlorate Information Bureau said in a press release.
The Perchlorate Information Bureau is supported by Aerojet, American Pacific Corporation, ATK and Lockheed Martin. Lowering the MCL to 1 ppb “would necessarily entail substantial costs for water purveyors and consumers and take more water supplies offline – all at a time when the state (most especially farmers in the Central Valley) is already facing historic, severe drought and massive reductions in water supplies,” according to the press release.