Christopher M. Teaf

The Passaic River Creel/Angler Survey: Expert Panel Review, Findings, and Recommendations

A Creel/Angler Survey (CAS) was conducted to provide site-specific information on recreational fishing in the lower six miles of the Passaic River (Study Area). Information collected during the CAS will be used to develop site-specific exposure factors, including fish consumption rates, for use in the human health risk assessment required by an Administrative Order on Consent as part of the Remedial Investigation/Feasibility Study for the Study Area. An expert panel was convened to provide an independent opinion regarding the need for, design of, and implementation of the CAS. The expert panel was charged with evaluating whether the conduct of a CAS is necessary to support an accurate risk assessment for the Study Area and whether the proposed CAS is sufficient to characterize local fish consumption behavior for risk assessment purposes. The expert panel agreed that a CAS is necessary and concluded that the proposed CAS, with specific modifications to the study design and data analysis, would provide the information necessary to estimate site-specific fish consumption rates. Revision of the CAS to accommodate the expert panel recommendations enhanced the quality of the data collected and ensured that the data will support the assessment of human health risks from consumption of fish from the Study Area.

Current Risk Assessment Approaches to Address Petroleum Hydrocarbon Mixtures in Soils

Products that exist as complex chemical mixtures, such as petroleum products, are used widely in commerce, and accidental releases of these products into the environment have led to thousands of contaminated sites nationwide. Developing sound estimates of potential health risks posed by these sites is challenging because of the composition of these products, their behavior in the environment, and the paucity of toxicological information available for many of the component compounds. In developing risk based cleanup goals for petroleum products and other complex commercial mixtures, the simplest approach is to assume that the entire mixture is comprised of the most toxic constituent, particularly when standards are unavailable for each of the components of the mixture. This approach often results in excessively conservative regulatory goals; thus, methods are needed which more accurately reflect the actual composition and aggregate toxicity of the mixture. Three approaches for the development of risk based...

Human Health and Environmental Risks Associated with Contaminated Military Sites

Public health interest in the investigation, evaluation and remediation of abandoned Soviet military bases in Central and Eastern Europe has intensified as the ownership, and hence the future use, of these facilities has come under the control of the host country in which the base is located. Some of the sites are located in or near heavily populated areas, and in some cases the intention is to convert the base and its associated infrastructure to other uses, including residential housing or commercial facilities.

Risk assessment as a tool for water resources decision-making in Central Asia

Risk Assessment, Risk Management and Risk Communication: Principles and Applications.- Assessment, Management and Cleanup of Radiological Contamination in Water: Methods and Challenges.- Engineering Considerations Regarding Withdrawal, Testing, Treatment, Distribution and Reuse of Water.- Implementation of Health-Based Guidelines for Water Supplies in Europe and Central Asia: Management Considerations for Municipal Authorities Regarding Water Quantity and Quality.- Approaches to the Evaluation and Protection of Groundwater and Surface Water in Situations with Competing Regional Uses.- Successfully Managing Multiple Uses of Water: Practical Aspects and Case Studies.- Radioactive Contamination of Aquatic Ecosystems: Source, Transfer and Countermeasures.- Ecological Risk Assessment Through Landscape Science Approaches.- Impact of Oil Field Activities on Water Resources.- Water Resources and Sustainable Development in Central Asia: Roles of Risk Assessment and Risk Management.- Risk Assessment in Kazakhstan.- An Introduction into the Environmental Performance of Sustainable Development in Mongolia.- Selected Industrial and Energy Related Facilities in Central Asia: Examples of Water Resource Impacts.- Analysis of Possible Risks Associated with the Application of Water Resources in Kyrgyzstan.- Status and Problems of Water Resources in Azerbaijan.- Risk and Environmental Impact Assessment Decision Making for Management of Water Resources in Kazakhstan.- Problems and Perspectives of Saving Sarez Lake.- Assessment of the Influence of River Runoff Regulation on Ecological Situation.- The Importance of Scientific Cooperation among Asian Countries in the Study and Risk Assessment of Water Resources in Central Asia.- Water Resources and Risk Assessment Considerations in Armenia.- Water Resources and Risk Assessment Considerations in Uzbekistan.- IV. Conclusion and Workshop Recommendations.- Abbreviations and Acronyms.

Nickel Carcinogenicity in Relation to the Health Risks from Residual Oil Fly Ash

ABSTRACT Epidemiological studies of workers in the nickel industry, animal exposure studies, and reports on the potential mechanisms of nickel-induced toxicity and carcinogenicity indicate that only crystalline sulfidic nickel compounds have been clearly established as carcinogenic or potentially carcinogenic in humans. This observation indicates the need to modify and update regulatory approaches for nickel to reflect noncancer toxicity values for some individual nickel species. Analysis of nickel compounds in residual oil fly ash (ROFA) indicates that sulfidic nickel compounds (e.g., nickel subsulfide, nickel sulfide) are not present. Thus, the potential for emission of carcinogenic nickel compounds from residual oil fly ash appears to be low. Preliminary reference concentrations (RfCs) for a number of nickel compounds, based on non-carcinogenic endpoints, are proposed on the basis of the benchmark dose approach in conjunction with NTP data for nickel species.

Natural Background and Anthropogenic Arsenic Enrichment in Florida Soils, Surface Water, and Groundwater: A Review with a Discussion on Public Health Risk

Florida geologic units and soils contain a wide range in concentrations of naturally-occurring arsenic. The average range of bulk rock concentrations is 1 to 13.1 mg/kg with concentrations in accessary minerals being over 1000 mg/kg. Florida soils contain natural arsenic concentrations which can exceed 10 mg/kg in some circumstances, with organic-rich soils often having the highest concentrations. Anthropogenic sources of arsenic have added about 610,000 metric tons of arsenic into the Florida environment since 1970, thereby increasing background concentrations in soils. The anthropogenic sources of arsenic in soils include: pesticides (used in Florida beginning in the 1890’s), fertilizers, chromated copper arsenate (CCA)-treated wood, soil amendments, cattle-dipping vats, chicken litter, sludges from water treatment plants, and others. The default Soil Cleanup Target Level (SCTL) in Florida for arsenic in residential soils is 2.1 mg/kg which is below some naturally-occurring background concentrations in soils and anthropogenic concentrations in agricultural soils. A review of risk considerations shows that adverse health impacts associated with exposure to arsenic is dependent on many factors and that the Florida cleanup levels are very conservative. Exposure to arsenic in soils at concentrations that exceed the Florida default cleanup level set specifically for residential environments does not necessarily pose a meaningful a priori public health risk, given important considerations such as the form of arsenic present, the route(s) of exposure, and the actual circumstances of exposure (e.g., frequency, duration, and magnitude).

Soil Cleanup Goal for Dioxin Using Probabilistic Risk Assessment Techniques

ABSTRACT State regulators in Florida recently approved a first-of-its-kind probabilistic risk assessment (PRA) for determining an alternative residential Soil Cleanup Target Level (SCTL) for dioxin (32 ng/kg TEQ). The default residential SCTL (7 ng/kg TEQ) is based on a single, deterministic calculation with numerous conservative assumptions, resulting in an overly conservative value far beyond the regulatory mandate (i.e., 10−6 increase in cancer risk). Conversely, this PRA used a Monte Carlo simulation to estimate risk for all members of a large population using a combination of scientific data and professional judgment, with final details developed during negotiations with regulators. The simulation parameters were defined probabilistically and reflect the ranges of values for the following exposure variables: body weight, exposure duration, exposure frequency, fraction from contaminated source, soil ingestion rate, and relative bioavailability. Other variable and uncertain parameters were treated deterministically per direction from the regulators. The state also required that a pre-supposed high-risk subpopulation be analyzed separate from the full receptor population. Despite the conservativeness of the alternative SCTL, this PRA represents a significant step toward more realistic estimates of human health risks caused by environmental contaminant exposure.

Risk Assessment Applications Beyond Baseline Risks and Clean-Up Goals

Historically, the phrase “Risk Assessment” brought to mind a thick Superfund-type baseline risk assessment or clean-up goal derivation document filled with pages of tables with endless seemingly unrelated algorithms and numbers. Over the last decade, the principles of risk and exposure assessment have gained wide-reaching acceptance and are increasingly utilized to help solve other environmental impact, occupational health, or risk mitigation design problems. The typical objective of the classic risk assessment is the evaluation of current or future risks from exposure to contaminated media within the framework of a regulatory waste management or remediation program. Risk-based techniques are increasingly being used on a voluntary basis (i.e., outside of the standard regulatory arena) to demonstrate the presence, absence, or extent of environmental or health-related concerns in specific exposure circumstances. Likewise, a risk or exposure evaluation may be useful in determining the need for, or the legitimacy of, a public health advisory, alone or in conjunction with remedial or mitigative actions. Finally, risk-based techniques often find their way into the courtroom. Three case studies are presented in which riskbased solutions were employed to assist in resolving environmental or health-related issues: (1) a reversal of a fish consumption advisory; (2) an evaluation of arsenic in soil on and adjacent to a school facility; and (3) a challenge to a case of alleged methyl bromide exposure in a litigation context. In each case, the use of risk assessment principles was employed beyond the classic baseline risk assessment to address an applied problem of toxicological significance.

Conclusion & Workshop Recommendations

The materials presented at this Advanced Research Workshop provided a detailed overview of the role played by risk assessment in the management of water resources in Central Asia and elsewhere. The experts from NATO countries presented a detailed information on methods to assess problems related to water quality and quantity on a municipal level, using international, peer reviewed indicators, and international instruments for the fight against water-related diseases. The Central Asian countries inherited from the former Soviet Union system a normative/methodical approach to application of numerical environmental management criteria, which has no specific option for risk assessment, and in most of these countries water resources are the exclusively property of the State. The transition to a market economy requires new methods to manage the use of water resources, and to assess and prevent negative consequences to the environment. Currently, the methodology of environmental risk assessment is a new, rapidly developing interdisciplinary scientific approach not only in the Central Asian countries but also in other countries of the Commonwealth of Independent States. There is an urgent need for the introduction of risk assessment methods in the environmental decision-making process in this part of the world.