Liability Associated with Emerging Constituents of Concern In the Environment
Modern industrialized societies rely on thousands of chemicals in everyday life, for agricultural, manufacturing and domestic applications. As of September 2014, there were more than 45 million organic and inorganic substances listed in the CAS registry of the American Chemical Society, with about 4000 new substances added each day.
In contrast to classic “priority pollutants” (or persistent organic pollutants), such as PCE, PCBs or PAHs, whose primary sources are industrial solvents/drycleaners, transformers and combustion processes, many of the “emerging contaminants” of current interest have domestic waste as their predominant source – either in the form of sewage or septic tank effluent or landfill leachates.
Research is documenting with increasing frequency that many chemical and microbial constituents that have not historically been considered as contaminants are present in the environment on a global scale. These "emerging contaminants" or “emerging constituents” or “contaminants of emerging concern” are commonly derived from commercial, residential, municipal, agricultural, and industrial wastewater sources and pathways. Types of contaminants include some pharmaceuticals, lotions, soaps, sunscreens, insect repellents, household cleaners, over-the-counter medications, herbicides, pesticides and chemicals used in manufacturing such as bisphenol A (BPA). See table below for a partial list of detected constituents.
U.S. EPA and several states are working to improve its understanding of a number of CECs, particularly pharmaceuticals and personal care products (PPCPs) and perfluorinated compounds among others.
These newly recognized contaminants represent a shift in traditional thinking as many are produced industrially yet are dispersed to the environment from domestic, commercial, and industrial uses.
"Emerging contaminants" can be broadly defined as any synthetic or naturally occurring chemical or any microorganism that is not commonly monitored in the environment but has the potential to enter the environment and cause known or suspected adverse ecological and (or) human health effects. In some cases, release of emerging chemical or microbial contaminants to the environment has likely occurred for a long time, but may not have been recognized until new detection methods were developed. In other cases, synthesis of new chemicals or changes in use and disposal of existing chemicals can create new sources of emerging contaminants.
While not a public health issue, the emerging contaminants have been detected in drinking water supplies at trace levels and can affect some consumers’ perception of drinking water quality. In fact, an independent survey conducted recently indicated that 63 percent of Americans are concerned about pharmaceuticals and other contaminants in their drinking water. In California where the water will soon be almost as valuable as gold, and with the plans for using more and more of recycled water, the presence of these constituents in the water is of major concern.
Emerging Constituents are usually unregulated chemicals. However, regulatory requirements will change as new information is developed. To that end, additional data are needed to characterize the presence and persistence of Emerging Constituents in various water sources. This information, along with epidemiological and toxicological data, is used to set priorities for developing new drinking water standards, new water quality standards, new state notification levels and new monitoring requirements.
Once Emerging Constituents have been detected, the question naturally arises as to what effect, if any, these compounds may have on people and the environment. Several different regulatory agencies share responsibility for determining the acceptable concentration of these chemicals. This is a formidable task as there are tens of thousands of chemical compounds in common use. Consequently, state and federal authorities rely on sales/usage information and monitoring data (from studies such as this one) to help determine appropriate research and regulatory priorities.
Emerging Constituents are not targeted for removal by filtration or other treatment processes, but continue on to other water sources. As water moves from its origin (headwaters) through cities and downstream, each reiteration of this process works to concentrate those compounds not removed in either the drinking water or wastewater treatment process. Although Emerging Constituents can be removed by some modern facilities, not all treatment facilities are equipped to effectively remove Emerging Constituents. Traditional wastewater treatment does not effectively remove these Emerging Constituents, allowing them to move into the environment even after water has been treated.
The Sarbanes-Oxley Act of 2002 established new standards for all U.S. public company boards, management and public accounting firms. This landmark legislation triggered massive changes to virtually every aspect of corporate governance, business processes and management controls, financial management, external reporting and disclosures, independent auditing, and securities regulation. Similar legislation to improve corporate governance and management has also been enacted internationally.
Environmental liabilities – and their impacts on corporate financial statements – have not escaped the changes brought on by Sarbanes-Oxley. Stakeholders are seeking a higher level of accuracy and assurance when it comes to resolving environmental liabilities arising from legacy contamination. All of this overlies the "routine" technical complexities inherent in environmental remediation, including: uncertainties in the nature and extent of subsurface contamination; ever-tightening cleanup levels; changing regulatory requirements; emerging contaminants of concern; multiple technological approaches; impacts on facility operations and real estate values, and external drivers such as stakeholder reaction/acceptance. The responsibility to deliver this higher level of accuracy and assurance typically falls to corporate environmental managers, their staff, and their external environmental consultants and advisors.
In response to these changing requirements and expectations, the environmental and management professions have developed new standard practices/guidance, analytical methods and software tools for improving the cost estimating and cash flow management for environmental liabilities.
The effects of emerging claim and coverage issues on the insurance business are uncertain. As industry practices and legal, judicial, social and other environmental conditions change, unexpected and unintended issues related to claim and coverage may emerge. These issues may adversely affect the business by either extending coverage beyond the underwriting intent or by increasing the number or size of claims. Examples of emerging claims and coverage issues include, but are not limited to:
· judicial expansion of policy coverage and the impact of new theories of liability;
· the assertion of "public nuisance" or similar theories of liability, pursuant to which plaintiffs seek to recover monies spent to administer public health care programs, abate hazards to public health and safety and/or recover damages purportedly attributable to a "public nuisance";
· medical developments that link health issues to particular causes, resulting in liability claims;
· claims relating to unanticipated consequences of current or new products
Biological Activity of Steroid Hormones in U.S. Streams
Testing of U.S. streams has detected glucocorticoid and androgen biological activity. In a collaborative study between the National Cancer Institute (NCI), Laboratory of Receptor Biology and Gene Expression, the U.S. Geological Survey (USGS), and others, scientists studied the potential for the biological activity in streams of glucocorticoids and androgens hormones—both potential endocrine-disrupting chemicals. Scientists tested water samples using a new cell-based bioassay that tested for molecular responses triggered by the presence of glucocorticoids and androgens in water. They found glucocorticoid and androgen activity in 27 and 35 percent of the water samples, respectively, potentially indicating the widespread occurrence of these hormones in streams.
Glucocorticoids—steroid hormones commonly referred to as "stress hormones"—are known for their potential to decrease immune responses. Glucocorticoid-based pharmaceuticals (hydrocortisone and prednisone, for example) are widely prescribed to relieve inflammation. Androgens are anabolic steroidsthat affect the development and maintenance of male characteristics, as well as other physiological functions. Depending on the timing of exposure, glucocorticoids and androgens can affect the endocrine systems of living organisms, but unlike estrogenic chemicals, not much is known about their occurrence in the environment.
USGS scientists provided extracts for testing from more than 100 water samples from streams and rivers located in 14 States. The testing method the NCI researchers developed allowed them to detect the activation of cell receptors or genes that respond specifically to glucocorticoids or androgens. Activation of fluorescently tagged cell receptors led to visual evidence of the presence of glucocorticoids or androgens in the samples of stream water. Other molecular methods were used to confirm that specific genes were turned on.
Considering that both glucocorticoids and androgens influence body development and metabolism, and have the potential to influence normal reproductive, endocrine, and immune system function, their presence in the environment has potential implications for wildlife and human health.
Chemicals from Land-Applied Biosolids Persist in Soil
Soil sampling in Eastern Colorado indicated that some chemicals introduced to nonirrigated farmland through biosolids application persisted through 468 days, and some chemicals were sufficiently mobile to be detected in soil as deep as 126 centimeters below land surface.
A study by scientists from the U.S. Geological Survey (USGS) and Colorado State University-Puebloshows that some chemicals in biosolids that are applied to nonirrigated farmland are sufficiently persistent and mobile to move into the soil beneath farm fields. Biosolids are the treated solid-waste component of wastewater treatment plant effluent; about 50 percent of the biosolids produced in the United States are applied to land as a fertilizer.
The field-scale study was initiated in 2007 in a semi-arid environment in eastern Colorado on land with no previous history of biosolid application. Typical agronomic practices were employed in the study. The biosolids, soil, and crop were monitored for a year and a half, which enabled the evaluation of the persistence and movement of contaminants from biosolids into the soil column after biosolid application.
Measurements indicate that nonylphenols (commonly used in detergents and other manufacturing), benzo[a]pyrene (a polycyclic aromatic hydrocarbon and byproduct of incomplete combustion of organic matter), diethyl phthalate (commonly used in plastics), d-limonene (a solvent obtained from citrus fruits), HHCB (galaxolide, a polycyclic organic musk used in fragrances), and triclosan (an antimicrobial) had migrated downward through the soil by 468 days after application. The study also showed indications that uptake by mature wheat plants was minimal. Soil and biosolid samples that were collected before and after biosolids application and incorporation in the soil were analyzed for 57 chemicals of potential environmental concern. During harvest, wheat samples were collected from control fields and from fields on which biosolids had been applied.
Complex Mixture of Contaminants Persists in Streams Miles from the Source Natural processes in stream ecosystems such as dilution and microbial degradation are known to attenuate some contaminants to below levels that can cause harm to ecosystems. However, a team of U.S. Geological Survey (USGS) scientists has shown that many chemicals discharged from municipal wastewater treatment facilities persist for miles downstream at levels known, or suspected, to cause adverse health impacts to aquatic organisms—including endocrine disruption in fish. The study also showed that these persistent chemicals occur in complex mixtures with unknown ecological consequences.
Overall, there were 73 organic chemicals detected in the effluent from the Boulder, Colorado, wastewater treatment plant (WWTP) and 56 chemicals detected in Boulder Creek stream water below the WWTP discharge point. There were 98 organic chemicals detected in the effluent from the Ankeny, Iowa, WWTP and 71 chemicals detected in Fourmile Creek below the WWTP discharge point.
The mixtures contained metal complexing agents, detergent degradation products, personal care products, pharmaceuticals, steroidal hormones, pesticides, and other compounds. The highest concentration compounds (greater than 100 micrograms per liter) detected in both WWTP effluents were ethylenediaminetetraacetic acid (EDTA – a metal complexing agent) and 4- nonylphenolethoxycarboxylate (a detergent degradation product).
Concentrations of pharmaceuticals were lower (less than 1 microgram per liter), and several compounds, including carbamazepine (a drug used to control seizures) and sulfamethoxazole (an antibiotic), were detected throughout sections of the two streams that were studied.
The results, published in Environmental Science and Technology, are part of a long-term study of the fate, transport, and ecological effects of the wastewater discharged into two streams (Boulder Creek, Colorado, and Fourmile Creek, Iowa) from municipal wastewater treatment plants. In a unique field application, the scientists used a sampling approach that involved multiple locations along the streams (Lagrangian) to ensure water samples and chemistry were representative of a parcel of water as it flowed downstream from the point of wastewater discharge. Many of the contaminants from the complex mixture of multiple types of chemicals (see text box) showed little decrease in concentration, other than that due to dilution, as they flowed down the approximately 6- to 8-mile segments of the streams studied. Importantly, some of these contaminants persisted at concentrations that are known, or suspected, to cause sublethal health effects to exposed organisms. Furthermore, several chemicals in the complex mixtures identified in this study are steroidal hormones and/or other chemicals that mimic estrogen, which could have additive health effects. The ecological consequences of the complex contaminant mixtures the scientists identified are poorly understood.
This study was funded by the USGS Toxic Substances Hydrology Program and Hydrologic Research and Development Program. Additional support was received by the U.S. Environmental Protection Agency.
Detergents in Streams May Just Disappear
The Story of 4-n-nonylphenol Biodegradation in Stream Sediments
USGS scientist measuring pH and other water properties on the banks of Fourmile Creek, Iowa, before collecting a sediment sample for laboratory biodegradation experiments
Since about 2000, U.S. Geological Survey (USGS) scientists have been finding the chemical breakdown products (degradation products) of household detergents in streams downstream from wastewater treatment plants WWTPs. Detergent degradation products are among the most frequently detected compounds in stream samples and are among the compounds measured at the highest concentrations. Environmental professionals are concerned about these compounds because scientists have shown that a class of degradation products known as nonylphenols can disrupt normal hormonal (endocrine) function in fish. To help determine the environmental fate and transport of detergent degradation products discharged into streams from WWTPs, USGS scientists assessed the potential for naturally occurring microorganisms to remove one common detergent degradation product (4-n-nonylphenol) from stream sediments.
This process of natural degradation by microorganisms is called biodegradation. In a laboratory setting the scientists tested the ability of 4-n-nonylphenol to biodegrade naturally in the environment using actual stream sediment from three streams. Sediments were collected from upstream and downstream of WWTP discharges. The experiments demonstrated that naturally occurring microorganisms that inhabit the stream sediments can biodegrade 4-n-nonylphenol in sediments under oxic (with oxygen) conditions in the laboratory; however, no biodegradation was observed in the laboratory under anoxic (without oxygen) conditions. These results help explain the presence and absence of these compounds in the environment, and may suggest ways to enhance natural removal mechanisms. For example, WWTP practices that produce high dissolved-oxygen concentrations in sediment and water downstream of wastewater discharges could improve the potential for natural removal. Environmental professionals, water resource managers, and WWTP managers can use this information to develop sound programs and practices regarding the occurrence of emerging wastewater contaminants in the environment.
Reference
Bradley, P.M., Barber, L.B., Kolpin, D.W., McMahon, P.B., and Chapelle, F.H., 2008, Potential for 4-n-nonylphenol biodegradation in stream sediments: Environmental Toxicology and Chemistry, v. 27, no. 2, p. 260-265, doi:10.1897/07-333.
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