CBRA Bulletin - March 2009

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This new Community-Based Risk Assessment (CBRA) Listserv is sponsored by the Environmental Protection Agency (EPA) and managed through the EPA's National Center of Environmental Research (NCER). Please feel free to forward the listserv messages to interested colleagues or ask them to join!

News and Opportunities | Featured Resource | Featured Science Articles

News and Opportunities

EPA/NCER Funding Opportunity:
Cumulative Risk Assessment The Environmental Protection Agency (EPA), as part of its Science to Achieve Results (STAR) program, is seeking applications from interdisciplinary teams to address research needs that currently limit the ability to conduct cumulative risk assessments. This unique Request for Applications (RFA) seeks to build the scientific basis for understanding chemical risk in "real-life" situations. Such situations include communities in which exposure to chemicals does not occur in isolation, but rather in combination with other environmental stressors.
This RFA focuses on two challenges that exist in conducting cumulative risk assessments: (a) the development of statistical and other analytical techniques that will enable the analysis of disparate types of data, and (b) the evaluation of the combined effects of nonchemical and chemical stressors. This RFA requires researcher-community collaborations. Applications are due June 17. For more details, see: http://es.epa.gov/ncer/rfa/2009/2009_star_cumulative_risk.html.

Unnatural Causes Series Wins Prestigious Broadcast Award
The seven-part documentary series, Unnatural Causes: Is Inequality Making Us Sick?, was selected for an Alfred I. duPont-Columbia Award for excellence in broadcast journalism. Produced by California Newsreel, the documentary series was broadcasted by Public Broadcasting Service (PBS) in spring 2008. Unnatural Causes explores how population health is shaped by the social and economic condition in which we are born, live, and work. Through portraits of individuals and families across the U.S., the series reveals the root causes and extent of our alarming health inequities and searches for solutions. Learn more about the documentary series, at: www.unnaturalcauses.org . Click here to find more information about DuPont-Columbia University Awards, including other Award winners.

NIEHS Funding Opportunity:
Environmental Health Sciences Core Center Grants The National Institute of Environmental Health Sciences (NIEHS) invites applications from qualified institutions for support of Environmental Health Sciences Core Centers. These centers are designed to establish innovative programs of excellence in the field of environmental health sciences by providing scientific and programmatic support for promising investigators and areas of research. Applications are due March 27. For more details, see: http://www07.grants.gov/search/search.do?&mode=VIEW&flag2006=false&oppId=44829

CCHE Releases Report The Legacy of Partnership
Enduring Practices and Sustainable Models from the Partnership for the Public's Health Initiative The Center for Community Health and Evaluation (CCHE) and the California Endowment have released the final report on the legacy evaluation of the Partnership for the Public's Health Initiative. The Legacy of Partnership presents findings from an evaluation four years after funding ended. It demonstrates what is possible when health departments and communities are able to successfully work together over a long period of time. The report highlights examples and evidence of collaborative partnerships, as well as challenges and lessons learned of partnerships which may "contribute to the success of future collaborative partnerships and support a paradigm shift in public health." Find the report, at: http://cche.org/conference/2008/publications/cche-publications_LegacyOfPartnership.pdf . Click for information regarding CCHE or Partnership for the California Endowment.

EPA Request for Applications
Smart Growth Implementation Assistance The Environmental Protection Agency (EPA) is seeking applications for technical assistance from communities that want to incorporate smart growth in their future development to meet environmental and other community goals. Eligible entities are tribal, local, regional, and state governments, and nonprofit organizations that have demonstrated partnerships with a governmental entity. EPA is soliciting applications for assistance with either policy analysis or public participatory processes. Selected communities or states will receive assistance in the form of a multi-day visit from a team of experts organized by EPA and other national partners. Applications are due April 23. For more information and application materials, see: http://epa.gov/smartgrowth/2009_sgia_rfa.htm. Click for more information on EPA's Smart Growth resources or EPA's Smart Growth Implementation Assistance Program.

ICCA-LRI Sponsoring Connecting Innovations in Biological, Exposure and Risk Sciences
Better Information for Better Decisions Workshop (June 16-17, 2009) A new generation of scientific tools is emerging that can rapidly measure the effects of chemicals on cells, tissues and organisms. The International Council of Chemical Associations' Long-Range Research Initiative (ICCA-LRI) is sponsoring this workshop to stimulate discussions on approaches to translate the data from these new technologies into information that is effective and useful for risk-based decision making. Information about the Workshop can be found at: https://secure.z-techcorp.com/cmt/meetings/meeting_detail.cfm?meeting_id=310 . Find more information on ICCA or ICCA's LRI program.

NIH Funding Opportunity
Centers for Population Health and Health Disparities The National Institutes of Health (NIH) is soliciting grant applications for their Centers for Population Health and Health Disparities (CPHHD) Program. This funding opportunity is jointly sponsored by the National Cancer Institute (NCI), the National Heart, Lung and Blood Institute (NHLBI) and Office of Behavioral and Social Sciences of NIH. The CPHHD Program is designed to promote trans-disciplinary research in the area of health inequities. The focus is on understanding the pathways that result in disparate health outcomes and on developing comprehensive models of how various social, economic, cultural, environmental, biological, behavioral, physiological, and genetic factors affect individual health outcomes and their distribution in populations. Applications are due May 29. More information is available at: http://www07.grants.gov/search/search.do?&mode=VIEW&flag2006=false&oppId=44508.

EPA and NRC Sponsoring Toxicity Pathway-Based Risk Assessment
Preparing for Paradigm Change Workshop (May 11-13, 2009) In preparation for a revolution in toxicity testing, the National Research Council and the Environmental Protection Agency are sponsoring a symposium to stimulate discussion on how the influx of emerging data may be applied to improve qualitative and quantitative aspects of risk assessment. It will also consider how new technologies may change the approach to risk assessment. A "Call for Poster Session Abstracts" is ongoing until March 27. Limited funds are available for poster presenters. Information about the Workshop can be found at: www.nas.edu/toxsymposium.

Featured Resource

Toxipedia - Connecting Science and People Toxipedia is a modified-wiki Website that offers a free toxicological encyclopedia written by experts and edited for accuracy. It is a Website and a tool for public health professionals, students, and the public to use and educate one another. Toxipedia was initiated in June 2006. An Advisory Board was established in May 2008 to help develop and implement strategies that will propel toxipedia forward. Steven G. Gilbert, a toxicologist, is the executive director and managing editor of toxipedia. The toxipedia Website offers:

When visiting the Toxipedia Website, you can also subscribe to the toxipedia newsletter. Visit toxipedia at: www.toxipedia.org .

Featured Science Articles

Research Needs for Community-Based risk Assessment: Findings from a Multi-Disciplinary Workshop
Journal of Exposure Science and Environmental Epidemiology (Epublication ahead of print) by Yolanda Anita Sanchez, Kacee Deener, Elaine Cohen Hubal, Carrie Knowlton, David Reif, and Deborah Segal

Abstract: Communities face exposures to multiple environmental toxicants and other non-chemical stressors. In addition, communities have unique activities and norms that influence exposure and vulnerability. Yet, few studies quantitatively consider the role of cumulative exposure and additive impacts. Community-based risk assessment (CBRA) is a new approach for risk assessment that aims to address the cumulative stressors faced by a particular community, while incorporating a community-based participatory research framework. This paper summarizes an Environmental Protection Agency (EPA) sponsored workshop, "Research Needs for Community-Based Risk Assessment." This workshop brought together environmental and public health scientists and practitioners for fostering an innovative discussion about tools, methods, models, and approaches for CBRA. This workshop was organized around three topics:
1. Data and Measurement Methods;
2. The Biological Impact of Non-Chemical Stressors and Interaction with Environmental Exposures; and
3. Statistical and Mathematical Modeling. This report summarizes the workshop discussions, presents identified research needs, and explores future research opportunities in this emerging field.

The Road to Linearity: Why Linearity at Low Doses Became the Basis for Carcinogen Risk Assessment
Archives of Toxicology (Epublication ahead of print) by EJ Calabrese

Abstract: This article assesses the historical foundations of how linearity at low dose became accepted by the scientific/regulatory communities. While the threshold model was used in the 1920s/1930s in establishing radiation health standards, its foundations were challenged by the genetics community who argued that radiation induced mutations in reproductive cells followed a linear response, were cumulative and deleterious.

Scientific foundations of linearity for gonadal mutations were based on non-conclusive evidence as well as not being conducted at low doses.

Following years of debate, leaders in the genetics community participated in the U.S. National Academy of Sciences (NAS) (1956) Biological Effects of Atomic Radiation (BEAR) BEAR I Committee, getting their perspectives accepted, incorporating linearity for radiation-induced mutational effects in risk assessment. Overtime the concept of linearity was generalized to include somatic effects induced by radiation based on a protectionist philosophy. This affected the course of radiation-induced and later chemically-induced carcinogen risk assessment. Acceptance of linearity at low dose from chemical carcinogens was strongly influenced by the NAS Safe Drinking Water Committee report of 1977 which provided the critical guidance to the U.S. EPA to adopt linear at low dose modeling for risk assessment for chemical carcinogens with little supportive data, much of which has been either discredited or seriously weakened over the past 3 decades.

Nonetheless, there has been little practical change of regulatory policy concerning carcinogen risk assessment. These observations suggest that while scientific disciplines are self correcting, that regulatory 'science' fails to display the same self-correcting mechanism despite contradictory data.

Fine-Particulate Air Pollution and Life Expectancy in the United States
New England Journal of Medicine (Volume 360, No 4: 376-386) by Arden Pope III, Majid Ezzati, and Douglas W. Dockery

Abstract: BACKGROUND: Exposure to fine-particulate air pollution has been associated with increased morbidity and mortality, suggesting that sustained reductions in pollution exposure should result in improved life expectancy. This study directly evaluated the changes in life expectancy associated with differential changes in fine particulate air pollution that occurred in the United States during the 1980s and 1990s.

METHODS: We compiled data on life expectancy, socioeconomic status, and demographic characteristics for 211 county units in the 51 U.S. metropolitan areas with matching data on fine-particulate air pollution for the late 1970s and early 1980s and the late 1990s and early 2000s. Regression models were used to estimate the association between reductions in pollution and changes in life expectancy, with adjustment for changes in socioeconomic and demographic variables and in proxy indicators for the prevalence of cigarette smoking. RESULTS: A decrease of 10 microg per cubic meter in the concentration of fine particulate matter was associated with an estimated increase in mean (+/-SE) life expectancy of 0.61+/-0.20 year (P=0.004). The estimated effect of reduced exposure to pollution on life expectancy was not highly sensitive to adjustment for changes in socioeconomic, demographic, or proxy variables for the prevalence of smoking or to the restriction of observations to relatively large counties. Reductions in air pollution accounted for as much as 15% of the overall increase in life expectancy in the study areas.

CONCLUSIONS: A reduction in exposure to ambient fine-particulate air pollution contributed to significant and measurable improvements in life expectancy in the United States.

Toxic Ignorance and Right-to-Know in Biomonitoring Results
Communication: A Survey of Scientists and Study Participants Environmental Health (Volume 8, Article Number 6) by Rachel Morello-Frosch, Julia G. Brody, Phil Brown, Rebecca G. Altman, Ruthann A Rudel, and Carla Perez

Abstract: BACKGROUND: Exposure assessment has shifted from pollutant monitoring in air, soil, and water toward personal exposure measurements and biomonitoring. This trend along with the paucity of health effect data for many of the pollutants studied raise ethical and scientific challenges for reporting results to study participants.

METHODS: We interviewed 26 individuals involved in biomonitoring studies, including academic scientists, scientists from environmental advocacy organizations, IRB officials, and study participants; observed meetings where stakeholders discussed these issues; and reviewed the relevant literature to assess emerging ethical, scientific, and policy debates about personal exposure assessment and biomonitoring, including public demand for information on the human health effects of chemical body burdens. RESULTS: We identify three frameworks for report-back in personal exposure studies: clinical ethics; community-based participatory research; and citizen science 'data judo.' The first approach emphasizes reporting results only when the health significance of exposures is known, while the latter two represent new communication strategies where study participants play a role in interpreting, disseminating, and leveraging results to promote community health. We identify five critical areas to consider in planning future biomonitoring studies.

CONCLUSION: Public deliberation about communication in personal exposure assessment research suggests that new forms of community-based research ethics and participatory scientific practice are emerging.

Free article access available via Environmental Health: http://www.ehjournal.net/content/8/1/6

Particulate Air Pollution, Coronary Hear Disease and Individual Risk Assessment: A General Overview
European Journal of Cardiovascular Prevention and Rehabilitation (Volume 16, No 1: 10-15) by Hassing C, Twickler M, Brunekreef B, Cassee F, Doevendans P, Kastelein J, and Cramer MJ

Abstract: Both long-term and short-term exposure to air pollution is associated with a marked increase in cardiovascular morbidity and mortality because of the coronary syndrome and its complications. The exact molecular mechanism that is responsible for these acute and chronic effects is not elucidated yet. Potential pathophysiological pathways, however, include vascular dysfunction, inflammation, and oxidative stress and altered cardiac autonomic dysfunction. Actually, the cardiovascular risk assessment for individual patients with regard to air pollution is still complicated. To support decision-making in clinic, we propose a risk model, named 'CardioVascular and AIR pollution' risk table, composed of acknowledged factors in the relationship of cardiovascular disease and air pollution.

Hazard to the Developing Male Reproductive System From Cumulative Exposure to Phthalate Esters - Dibutyl Phthalate, Diisobutyl Phthalate, Butylbenzyl Phthalate, Diethylhexyl Phthalate, Dipentyl Phthalate, and Diisononyl Phthalate
Regulatory Toxicology and Pharmacology (Volume 53 No 2: 90-101) by R Benson

Abstract: Phthalate esters are found in a wide variety of consumer and food packing products. Hence there is widespread exposure of the human population to these chemicals. Some of the phthalate esters are known to be toxic to the developing male reproductive system. This paper derives a reference dose (RfD) for each of the phthalate esters (dibutyl phthalate, diisobutyl phthalate, butylbenzyl phthalate, diethylhexyl phthalate, dipentyl phthalate, and diisononyl phthalate) that cause these effects. As these phthalate esters cause similar adverse biological effects and have the same mechanism of action, it is appropriate in a risk assessment to consider the potential adverse effects from cumulative exposure to these chemicals using a dose addition model. This paper provides examples of a cumulative risk assessment using the hazard index and relative potency approaches from the RfDs derived from studies in laboratory animals and exposure information in people. The results of the cumulative risk assessments for both a US and a German population show that the hazard index is below one. Thus it is unlikely that humans are suffering adverse developmental effects from current environmental exposure to these phthalate esters.

Determination of No-Observed Effect Level (NOEL) - Biomarker Equivalents to Interpret Biomonitoring Data for Organophosphorus Pesticides in Children
Environmental Health (Volume 8, Article Number 5) by Mathieu Valcke and Michele Bouchard

Abstract: BACKGROUND: Environmental exposure to organophosphorus pesticides has been characterized in various populations, but interpretation of these data from a health risk perspective remains an issue. The current paper proposes biological reference values to help interpret biomonitoring data related to an exposure to organophosphorus pesticides in children for which measurements of alkylphosphate metabolites are available.

METHODS: Published models describing the kinetics of malathion and chlorpyrifos in humans were used to determine no-observed effect level - biomarker equivalents for methylphosphates and ethylphosphates, respectively. These were expressed in the form of cumulative urinary amounts of alkylphosphates over specified time periods corresponding to an absorbed no-observed effect level dose (derived from a published human exposure dose) and assuming various plausible exposure scenarios. Cumulative amounts of methylphosphate and ethylphosphate metabolites measured in the urine of a group of Quebec children were then compared to the proposed biological reference values.

RESULTS: From a published no-observed effect level dose for malathion and chlorpyrifos, the model predicts corresponding oral biological reference values for methylphosphate and ethylphosphate derivatives of 106 and 52 nmol/kg of body weight, respectively, in 12-h nighttime urine collections, and dermal biological reference values of 40 and 32 nmol/kg of body weight. Out of the 442 available urine samples, only one presented a methylphosphate excretion exceeding the biological reference value established on the basis of a dermal exposure scenario and none of the methylphosphate and ethylphosphate excretion values were above the obtained oral biological reference values, which reflect the main exposure route in children.

CONCLUSION: This study is a first step towards the development of biological guidelines for organophophorus pesticides using a toxicokinetic modeling approach, which can be used to provide a health-based interpretation of biomonitoring data in the general population.

Free article access available via Environmental Health: http://www.ehjournal.net/content/8/1/5

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