Industrial Health Risk Assessment for Routine Workers in a Military Paint Shop

An industrial health risk assessment was conducted for employees engaged in routine tasks in a military paint shop. These workers handle a variety of compounds, including chromates, volatile organic compounds, and isocyanates. A risk assessment conforming to well-accepted, widely used guidance was conducted. The site-specific assessment incorporated data on task durations and personal protective equipment (PPE) use. The estimated chronic daily intake (CDI) for routine on-site workers was compared to U.S. Environmental Protection Agency (U.S. EPA) Reference Doses (RfDs) to estimate the likelihood of non-cancer effects. When the U.S. EPA's Integrated Risk Information System (IRIS) lacked RfDs for compounds, efforts were made to utilize surrogates or guidance from other agencies. For carcinogenic effects the CDI was multiplied by the U.S. EPA slope factor and the resultant risk estimate compared to target incremental risk ranges. Using PPE recommended by the site's industrial hygiene department, it is anticipated that the U.S. EPA non-cancer threshold hazard index (HI) of 1.0 and target incremental cancer risk (R) of 10^?4 to 10^?6 will not be exceeded. However, under baseline modeling assumptions (i.e., no use of PPE), the concentrations of chemicals of potential concern (COPC) present in the air during routine operations suggest a potential health hazard. The baseline estimates emphasize the importance of proper PPE in the paint shop workplace and use of site-specific information in modeling.

     

Framework for Human Health Risk Assessment

The views expressed in this paper are those of the authors and do not necessarily reflect the views or policies of the USEPA. The U.S. Government has the right to retain a nonexclusive royalty-free license in and to any copyright covering this article. The U.S. Environmental Protection Agency has recognized the need to develop a framework for human health risk assessment that puts a perspective on the approaches in practice throughout the Agency. In response, the USEPA's Risk Assessment Forum has begun the process of developing a framework for human health risk assessment. This paper provides some additional background to the previous review of the framework efforts and notes the Agency's extramural efforts to begin the process of integrating and harmonizing risk assessment approaches for all human health endpoints.     

Use of the reference dose in risk characterization of drinking water contaminants

Regulatory decisions should be made in the most expert and informed way since they are precipitated by real and perceived threats to public health, under the glare of public scrutiny. The development of environmental regulations require a three‐step paradigm, collectively called risk analysis. This paper will address the risk assessment practices required under the Safe Drinking Water Act (SDWA) Amendments of 1986 to determine a Maximum Contaminant Level Goal (MCLG, nonenforceable health goal) which should result in no known or anticipated health effects, and allows adequate margin of safety. The end product of this risk assessment, risk characterization, and risk management encompassing control options and nonrisk analysis are combined to derive the Maximum Contaminant Level (MCL, enforceable standard). Furthermore, this paper discusses the U.S. Environmental Protection Agency's efforts in exploring new and improved noncancer risk assessment approaches providing the basis for MCLGs for the protection of human health.     

A lifestage approach to assessing children's exposure

Understanding and characterizing risks to children has been the focus of considerable research efforts at the U.S. Environmental Protection Agency (EPA). Potential health risks resulting from environmental exposures before conception and during pre‐ and postnatal development are often difficult to recognize and assess because of a potential time lag between the relevant periods of exposure during development and associated outcomes that may be expressed at later lifestages. Recognizing this challenge, a lifestage approach for assessing exposure and risk is presented in the recent EPA report titled A Framework for Assessing Health Risks of Environmental Exposures to Children (U.S. EPA, 2006 ). This EPA report emphasizes the need to account for the potential exposures to environmental agents during all stages of development, and consideration of the relevant adverse health outcomes that may occur as a result of such exposures. It identifies lifestage‐specific issues associated with exposure characterization for regulatory risk assessment, summarizes the lifestage‐specific approach to exposure characterization presented in the Framework, and discusses emerging research needs for exposure characterization in the larger public‐health context. This lifestage approach for characterizing children's exposures to environmental contaminants ensures a more complete evaluation of the potential for vulnerability and exposure of sensitive populations throughout the life cycle. Birth Defects Res (Part B) 2008. © 2008 Wiley‐Liss, Inc.     

Current Perspectives on Issues in Risk Assessment Methods

The Office of Research and Development (ORD) of the U.S. Environmental Protection Agency was reorganized in 1995 to follow the risk assessment paradigm developed by the National Research Council. With the reorganization, a number of different research strategies and plans were developed on problem-driven topics (e.g., arsenic, particulate matter, and microbial pathogens/disinfectant byproducts) as well as on core research (e.g., ecological research, human health risk assessment research, and pollution prevention research). The human health risk assessments research strategy, which is currently under development, addresses a variety of issues which affect all human health risk assessments. These include mechanism of action, variation in response, aggregate risk, and effect on public health. While all of the issues that have been identified are important, the challenge to ORD is to identify which will have the greatest impact on improving risk assessment so that resources can be most strategically applied.     

Predicting restoration outcomes based on organizational and ecological factors

For restoration to be an effective strategy to reverse large‐scale habitat loss and land degradation, funding programs need policies that promote selection of and commitment to projects that can reasonably be expected to succeed. Programmatic project selection practices have received minimal formal evaluation, despite their importance. In this study, we considered the extent to which a program needs to consider both ecological and organizational factors during project selection in order to minimize the incidence of project failure. Our assessment of a long‐term program that funds ecological restoration efforts across Minnesota (U.S.A.), based on project records, manager surveys, and field surveys, yielded several broadly relevant insights. First, factors well understood to confer ecological resilience (level of landscape alteration and starting condition) were clearly associated with restoration outcomes, regardless of time‐since‐initiation of restoration. Second, restoration of low‐resilience ecosystems is typically a labor‐ and skill‐intensive enterprise for organizations that undertake them. Our analysis revealed four organizational limitations, in addition to insufficient funds, that hindered capacity to keep projects on‐track: lack of planning and goal‐setting, inadequate staffing, leadership change, and incomplete records. Third, to reduce risk, programs do not necessarily need to avoid challenging projects, but do need to consider whether organizations proposing restorations have adequate internal capacity to competently plan and to sustain actions for a duration sufficient to restore ecological resilience. If a restoration is degraded enough to require human intervention to recover, the outcome of a project is as likely to reflect its organizational reality as much as its ecological circumstances.     

Indicators for Human and Ecological Risk Assessment: A U.S. Environmental Protection Agency Perspective

Assessment of risk to public health or environmental resources requires competent characterization of stressors and corresponding effects. Because of the complexity of most stressor-response relationships, it is impossible to completely characterize all the variables, so a select set of measurements is made to reflect the most critical components. Such measurements, or indicators, are included in monitoring programs to estimate trend, stressor source, or magnitude of effects and lead to thresholds for management action or restoration. Although a wide variety of programs and program objectives exists, there are some common challenges for indicator development, including a strong link to management actions. Indicator measurements used in U.S. Environmental Protection Agency (USEPA) risk assessment activities must stem from collaboration among managers, risk assessors, scientists and stakeholders. The primary objective of the USEPA's Fifth Symposium of the National Health and Ecological Effects Research Laboratory was to improve health and ecological risk assessment through dedicated sessions that maximized interaction and discussion among these groups. Existing measurements were challenged for appropriateness, efficiency and scientific validity. Emerging science was explored for greater understanding, better interpretation, and improved methodology. A secondary objective was to uncover and exploit common indicators and supporting data for human health and ecological models.     

Large‐Scale Zostera marina (eelgrass) Restoration in Chesapeake Bay,Maryland, USA. Part II: A Comparison of Restoration Methods in the Patuxent and Potomac Rivers

In response to systemic losses of submerged aquatic vegetation (SAV) in the Chesapeake Bay (east coast of North America), the U.S. Environmental Protection Agency's (EPA) Chesapeake Bay Program (CBP) and Maryland Department of Natural Resources (MD DNR) have considered SAV restoration a critical component in Bay restoration programs. In 2003, the CBP created the “Strategy to Accelerate the Protection and Restoration of Submerged Aquatic Vegetation in the Chesapeake Bay” in an effort to increase SAV area. As part of this strategy, large‐scale eelgrass (Zostera marina) restoration efforts were initiated in the Patuxent and Potomac Rivers in Maryland. From 2004 to 2007, nearly 4 million Z. marina seeds were dispersed over 10 ha on the Patuxent River and almost 9 million seeds over 16 ha on the Potomac River. Z. marina seedling establishment was consistent throughout the project (<4%); however, restored eelgrass survival was highly dependent on restoration site. Restoration locations on the Patuxent River experienced initial Z. marina seedling germination, but no long‐term plant survival. Restored Z. marina on the Potomac River has persisted and expanded, both vegetatively and sexually, beyond initial seeding areas. Healthy Z. marina beds now cover approximately five acres of the Potomac River bottom for the first time in decades. The differential success of Z. marina restoration efforts in the two rivers is evidence for the necessity of carefully considering site‐specific characteristics when using large‐scale seeding methods to achieve successful SAV restoration.     

Chromatographic evaluation of the toxicity in fish of pesticides

Ecotoxicity assessment is essential before placing new chemical substances on the market. An investigation of the use of the chromatographic retention (log k) in biopartitioning micellar chromatography (BMC) as an in vitro approach to evaluate the toxicity in fish of pesticides (acute toxicity levels as pLC(50)) is proposed. A heterogeneous data set of 85 pesticides from six chemical families with available experimental fish toxicity data (ECOTOX database from U.S. Environmental Protection Agency (EPA)) was used. For pesticides exhibiting non-polar narcosis mechanism in fish (non-specific toxicity), more reliable models and precise pLC(50) estimations are obtained from log k (quantitative retention-activity relationships, QRAR) than from log P (quantitative structure-activity relationships, QSAR) or ECOSAR (ECOSAR program from U.S. EPA).     

Universal influenza vaccination: the time to act is now

Annual influenza epidemics create a significant public health burden each year in the United States. That influenza continues to pose a public health threat despite being largely preventable through vaccination is indicative of continuing weaknesses in the U.S.'s public health system. Moreover, the burden of annual influenza epidemics and the fragility and instability of the capacity to respond to them underscore the U.S.'s ongoing vulnerability to pandemic influenza and highlights gaps in bioterrorism preparedness and response efforts. This article examines the burden of annual influenza epidemics in the U.S., efforts to combat that burden with vaccination, shortcomings of influenza vaccination efforts, and how those shortcomings exemplify weaknesses in pandemic influenza and bioterrorism preparedness efforts. We make the case for establishing an annual universal influenza vaccination program to assure access to influenza vaccination to anyone who can safely receive vaccination and desires it. Such a program could greatly reduce the annual burden of influenza while advancing and maintaining U.S. pandemic influenza and bioterrorism preparedness and response efforts.     

Framework for Human Health Risk Assessment

The U.S. Environmental Protection Agency has recognized the need to develop a framework for human health risk assessment that puts a perspective on the approaches in practice throughout the Agency. In response, the Agency's Risk Assessment Forum has begun the long-term process of developing a framework for human health risk assessment. The framework will be a communication piece that will lay out the scientific basis, principles, and policy choices underlying past and current risk assessment approaches and will provide recommendations for integrating/harmonizing risk assessment methodologies for all human health endpoints.     

Initial Risk-Based Screening of Potential Brownfield Development Sites

Brownfield redevelopment is sustainable only when it is a transparent process protective of public health. The objective of the brownfield health risk screening matrix is to provide a scientifically based, transparent process to evaluate human health risks on proposed redevelopment sites as well as a framework that can be critically evaluated by both environmentalists and the community in general. Public discussion and understanding of current health risk assessment, as well as the risks specific to each brownfield redevelopment site, are essential for an effective brownfield redevelopment program.

The Brownfields Redevelopment Program was started by the EPA in 1995 and seeks to use already contaminated sites rather than contaminate even more greenfields. Two of the biggest difficulties are making redevelopment profitable and protecting human health. Traditional human health risk assessment evaluates single chemical exposures and identifies the level below which no adverse effect will occur to the most sensitive subgroups of the population. For cancer–causing chemicals the risk must be lower than 1:1,000,000. When brownfield redevelopment sites are associated with high cost, extensive time and unmanageable uncertainty, additional greenfield sites will become contaminated and the contamination on current brownfield sites will remain un-remediated.

The citizens' advisory group addressing brownfields in a southern New York county has developed a risk matrix to evaluate the uncertainty of the available data, the toxicity of the known or suspected contaminants and the likely exposure routes for each brownfield site in the county. The matrix categorizes sites as high, medium or low risk according to exposure groups. The risk matrix complements the triad approach currently being developed by EPA to identify and manage project decision uncertainties, addresses uncertainty as well as toxicity and has the potential to reduce the cost of traditional health risk assessment at brownfield redevelopment sites.     

Application of GMOs in the U.S.: EPA research & regulatory considerations related to soil systems

During the last 20 years recombinant biotechnology has resulted in the development of organisms with unique genetic compositions, some of which are for intentional release to the environment. While concerns have been raised that such organisms may be capable of inducing transient unintended environmental effects, longer-term perturbations to soil processes and non-target species effects have yet to be demonstrated. In parallel with the growth of the commercial biotechnology industry has come a significant growth in regulatory review processes intended to evaluate the risks of these GMO products. Under the Toxic Substances Control Act (TSCA), certain new microbial products that undergo pre-manufacture review are examined for human and environmental risks using data and other information received in accordance with the U.S. Environmental Protection Agency’s (EPA’s) “Points to Consider” guidance document. In the risk assessment process, carried out under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and the Federal Food, Drug and Cosmetic Act (FFDCA) authorities, EPA evaluates both microbial pesticide products and plants with pesticidal properties to determine if Federal safety standards are met. For all pesticide products, including genetically engineered pesticides, EPA receives testing of product composition and chemical properties, human health effects, environmental effects on non-target pests, and the fate of the pesticide in the environment. The EPA’s Office of Research and Development supports risk assessment research related to such GMO products. This paper focuses on relevant EPA research and regulatory examples related to soil effects considerations for GMOs.     

Seasonal detection of human viruses and coliphage in Newport Bay, California

Recent studies have shown that the fecal indicator bacteria (FIB) currently used to indicate water quality in the coastal environment may be inadequate to reflect human viral contamination. Coliphage was suggested as a better indicator of human viral pollution and was proposed by the U.S. EPA as an alternative indicator for fecal pollution in groundwater. In this study, we investigated the occurrence and distribution of FIB, F+ coliphage, and PCR-detectable human adenovirus and enterovirus for an entire year at 15 locations around the Newport Bay watershed, an important southern California estuary for water recreation and an ecological reserve. Peak concentrations and prevalences of FIB and F+ coliphage were associated with winter storms (wet weather). Human adenoviruses and enteroviruses, however, were detected by PCR in approximately 5% of samples collected in the summer (dry weather) but only once in wet weather. These results demonstrated that FIB and coliphage have similar seasonal and freshwater-to-saltwater distribution patterns, while the detection of human viruses depends on a distribution pattern that is the opposite of that of FIB and coliphage. This research suggested that coliphage and FIB share similar environmental sources, while sources of human viruses in Newport Bay are perhaps different.     

Human exposure to endocrine disrupters: carcinogenic risk assessment

Human exposure to endocrine disrupters (EDs) is widespread and is considered to pose a growing threat to human health. Recent advances in molecular and genetic research and better understanding of mechanisms of blastic cell transformation have led to efforts to improve cancer risk assessment for populations exposed to this family of xenobiotics. In risk assessment, low dose extrapolation of cancer incidence data from both experimental animals and epidemiology studies has been largely based on models assuming linear correlation at low doses, despite existence of evidence showing otherwise. Another weakness of ED risk assessment is poor exposure data in ecological studies. Those are frequently rough estimates derived from contaminated items of local food basket surveys. Polyhalogenated hydrocarbons are treated as examples. There is growing sense of urgency to develop a biologically based dose response model of cancer risk, integrating emerging data from molecular biology and epidemiology to provide more realistic data for risk assessors, public, public health managers and environmental issues administrators.     

Assessment of reproductive risks

In the regulatory process, the hazards posed by potentially toxic agents to the female and male reproductive systems and to developing young are evaluated by risk assessment procedures. In this paper, toxicity testing and the regulatory process are discussed, with emphasis on risk assessment. The suggested testing protocols of the Pesticide Assessment Guidelines (U.S. EPA) are presented as an example of testing that might be done to produce toxicity data for an agent. Protocols and end points that are utilized in testing for reproductive effects are described. Included are acute, subchronic, chronic, and short-term tests. The four components of reproductive risk assessment (hazard identification, dose-response assessment, exposure assessment, and risk characterization) are examined. Effects of dibromochloropropane on rabbit testicular parameters are used to demonstrate approaches that could be taken in doing a reproductive risk assessment. Research needs for screening methods, adequate dose-response testing, toxicokinetics, end point development, and extrapolation methods are identified. Finally, this paper discusses selected areas in which changes in reproductive risk assessment are anticipated, as well as the mechanism for influencing the nature and extent of those changes.     

Can Ecological Receptors Really Be At Risk?

Birds and mammals at hazardous waste sites are routinely modeled for their potential to display harmful toxicological effects as a result of their exposures to contaminants. Although standard desktop measures of the potential for toxicological endpoints to be reached commonly suggest that these receptors should be at ill health (e.g., experiencing reproductive impairment), evidence is lacking from the field that such effects are occurring. Plausibly, the excessive time lapse (frequently several decades) from contaminant release event to site ecological risk assessment, can explain the disconnect. Aided by their relatively brief life spans, these modeled ecological receptors have produced multiple generations to date and may have outbred the chemical stress. In light of the absence of observed health impacts in birds and mammals since the creation of the U.S. Environmental Protection Agency's Superfund program, there may be no need to continue assessing the health of these species. Additionally, given the very few reported instances of observed health effects at terrestrial sites, it may be prudent to replace risk assessment with impact assessment as the essence of a revamped ecological assessment process.     

Framework for the Integration of Health and Ecological Risk Assessment

The World Health Organization's International Programme on Chemical Safety (IPCS), the Organization for Economic Cooperation and Development (OECD), and the U.S. Environmental Protection Agency have developed a collaborative partnership to foster integration of assessment approaches for human health and ecological risks. This paper presents the framework developed by that group. Integration provides coherent expressions of assessment results, incorporates the interdependence of humans and the environment, uses sentinel organisms, and improves the efficiency and quality of assessments relative to independent human health and ecological risk assessments. The paper describes how integration can occur within each component of risk assessment, and communicates the benefits of integration at each point. The goal of this effort is to promote the use of this internationally accepted guidance as a basis for harmonization of risk assessment.     

Seasonal Detection of Human Viruses and Coliphage in Newport Bay, California

Recent studies have shown that the fecal indicator bacteria (FIB) currently used to indicate water quality in the coastal environment may be inadequate to reflect human viral contamination. Coliphage was suggested as a better indicator of human viral pollution and was proposed by the U.S. EPA as an alternative indicator for fecal pollution in groundwater. In this study, we investigated the occurrence and distribution of FIB, F+ coliphage, and PCR-detectable human adenovirus and enterovirus for an entire year at 15 locations around the Newport Bay watershed, an important southern California estuary for water recreation and an ecological reserve. Peak concentrations and prevalences of FIB and F+ coliphage were associated with winter storms (wet weather). Human adenoviruses and enteroviruses, however, were detected by PCR in ~5% of samples collected in the summer (dry weather) but only once in wet weather. These results demonstrated that FIB and coliphage have similar seasonal and freshwater-to-saltwater distribution patterns, while the detection of human viruses depends on a distribution pattern that is the opposite of that of FIB and coliphage. This research suggested that coliphage and FIB share similar environmental sources, while sources of human viruses in Newport Bay are perhaps different.