A Niche for Infectious Disease in Environmental Health: Rethinking the Toxicological Paradigm

Objective

In this review we highlight the need to expand the scope of environmental health research, which now focuses largely on the study of toxicants, to incorporate infectious agents. We provide evidence that environmental health research would be strengthened through finding common ground with the tools and approaches of infectious disease research.

Data sources and extraction

We conducted a literature review for examples of interactions between toxic agents and infectious diseases, as well as the role of these interactions as risk factors in classic “environmental” diseases. We investigated existing funding sources and research mandates in the United States from the National Science Foundation and the National Institutes of Health, particularly the National Institute of Environmental Health Sciences.

Data synthesis

We adapted the toxicological paradigm to guide reintegration of infectious disease into environmental health research and to identify common ground between these two fields as well as opportunities for improving public health through interdisciplinary research.

Conclusions

Environmental health encompasses complex disease processes, many of which involve interactions among multiple risk factors, including toxicant exposures, pathogens, and susceptibility. Funding and program mandates for environmental health studies should be expanded to include pathogens in order to capture the true scope of these overlapping risks, thus creating more effective research investments with greater relevance to the complexity of real-world exposures and multifactorial health outcomes. We propose a new model that integrates the toxicology and infectious disease paradigms to facilitate improved collaboration and communication by providing a framework for interdisciplinary research. Pathogens should be part of environmental health research planning and funding allocation, as well as applications such as surveillance and policy development.     

The NIEHS Superfund Research Program: 25 Years of Translational Research for Public Health

Background

The Superfund Research Program (SRP) is an academically based, multidisciplinary, translational research program that for 25 years has sought scientific solutions to health and environmental problems associated with hazardous waste sites. SRP is coordinated by the National Institute of Environmental Health Sciences (NIEHS). It supports multi-project grants, undergraduate and postdoctoral training programs, individual research grants, and Small Business Innovation Research (SBIR) and Technology Transfer Research (STTR) grants.

Results

SRP has had many successes: discovery of arsenic’s toxicity to the developing human central nervous system; documentation of benzene toxicity to hematologic progenitor cells in human bone marrow; development of novel analytic techniques such as the luciferase expression assay and laser fragmentation fluorescence spectroscopy; demonstration that PCBs can cause developmental neurotoxicity at low levels and alter the genomic characteristics of sentinel animals; elucidation of the neurodevelopmental toxicity of organophosphate insecticides; documentation of links between antimicrobial agents and alterations in hormone response; discovery of biological mechanisms through which environmental chemicals may contribute to obesity, atherosclerosis, diabetes, and cancer; tracking the health and environmental effects of the attacks on the World Trade Center and Hurricane Katrina; and development of novel biological and engineering techniques to facilitate more efficient and lower-cost remediation of hazardous waste sites.

Conclusion

SRP must continue to address the legacy of hazardous waste in the United States, respond to new issues caused by rapid advances in technology, and train the next generation of leaders in environmental health science while recognizing that most of the world’s worst toxic hot spots are now located in low- and middle-income countries.

Citation

Landrigan PJ, Wright RO, Cordero JF, Eaton DL, Goldstein BD, Hennig B, Maier RM, Ozonoff DM, Smith MT, Tukey RH. 2015. The NIEHS Superfund Research Program: 25 years of translational research for public health. Environ Health Perspect 123:909–918; http://dx.doi.org/10.1289/ehp.1409247     

Environmental Health Indicators of Climate Change for the United States: Findings from the State Environmental Health Indicator Collaborative

Objective

To develop public health adaptation strategies and to project the impacts of climate change on human health, indicators of vulnerability and preparedness along with accurate surveillance data on climate-sensitive health outcomes are needed. We researched and developed environmental health indicators for inputs into human health vulnerability assessments for climate change and to propose public health preventative actions.

Data sources

We conducted a review of the scientific literature to identify outcomes and actions that were related to climate change. Data sources included governmental and nongovernmental agencies and the published literature.

Data extraction

Sources were identified and assessed for completeness, usability, and accuracy. Priority was then given to identifying longitudinal data sets that were applicable at the state and community level.

Data synthesis

We present a list of surveillance indicators for practitioners and policy makers that include climate-sensitive health outcomes and environmental and vulnerability indicators, as well as mitigation, adaptation, and policy indicators of climate change.

Conclusions

A review of environmental health indicators for climate change shows that data exist for many of these measures, but more evaluation of their sensitivity and usefulness is needed. Further attention is necessary to increase data quality and availability and to develop new surveillance databases, especially for climate-sensitive morbidity.     

The Relationship of Housing and Population Health: A 30-Year Retrospective Analysis

Objective

We analyzed the relationship between health status and housing quality over time.

Methods

We combined data from two nationally representative longitudinal surveys of the U.S. population and its housing, the National Health and Nutrition Examination Survey and the American Housing Survey, respectively. We identified housing and health trends from approximately 1970 to 2000, after excluding those trends for which data were missing or where we found no plausible association or change in trend.

Results

Changes in housing include construction type, proportion of rental versus home ownership, age, density, size, moisture, pests, broken windows, ventilation and air conditioning, and water leaks. Changes in health measures include asthma, respiratory illness, obesity and diabetes, and lead poisoning, among others. The results suggest ecologic trends in childhood lead poisoning follow housing age, water leaks, and ventilation; asthma follows ventilation, windows, and age; overweight trends follow ventilation; blood pressure trends follow community measures; and health disparities have not changed greatly.

Conclusions

Housing trends are consistent with certain health trends over time. Future national longitudinal surveys should include health, housing, and community metrics within a single integrated design, instead of separate surveys, in order to develop reliable indicators of how housing changes affect population health and how to best target resources. Little progress has been made in reducing the health and housing disparities of disadvantaged groups, with the notable exception of childhood lead poisoning caused by exposure to lead-based paint hazards. Use of these and other data sets to create reliable integrated indicators of health and housing quality are needed.     

U.S. Funding Is Insufficient to Address the Human Health Impacts of and Public Health Responses to Climate Variability and Change

Background

The need to identify and try to prevent adverse health impacts of climate change has risen to the forefront of climate change policy debates and become a top priority of the public health community. Given the observed and projected changes in climate and weather patterns, their current and anticipated health impacts, and the significant degree of regulatory discussion underway in the U.S. government, it is reasonable to determine the extent of federal investment in research to understand, avoid, prepare for, and respond to the human health impacts of climate change in the United States.

Objective

In this commentary we summarize the health risks of climate change in the United States and examine the extent of federal funding devoted to understanding, avoiding, preparing for, and responding to the human health risks of climate change.

Discussion

Future climate change is projected to exacerbate various current health problems, including heat-related mortality, diarrheal diseases, and diseases associated with exposure to ozone and aeroallergens. Demographic trends and geophysical and socioeconomic factors could increase overall vulnerability. Despite these risks, extramural federal funding of climate change and health research is estimated to be < $3 million per year.

Conclusions

Given the real risks that climate change poses for U.S. populations, the National Institutes of Health, Centers for Disease Control and Prevention, U.S. Environmental Protection Agency, and other agencies need to have robust intramural and extramural programs, with funding of > $200 million annually. Oversight of the size and priorities of these programs could be provided by a standing committee within the National Academy of Sciences.     

Respiratory and other health effects reported in children exposed to the World Trade Center disaster of 11 September 2001

Background

Effects of the World Trade Center (WTC) disaster on children’s respiratory health have not been definitively established.

Objective

This report describes respiratory health findings among children who were < 18 years of age on 11 September 2001 (9/11) and examine associations between disaster-related exposures and respiratory health.

Methods

Children recruited for the WTC Health Registry (WTCHR) included child residents and students (kindergarten through 12th grade) in Manhattan south of Canal Street, children who were south of Chambers Street on 9/11, and adolescent disaster-related workers or volunteers. We collected data via computer-assisted telephone interviews in 2003–2004, with interview by adult proxy for children still < 18 years of age at that time. We compared age-specific asthma prevalence with National Health Interview Survey estimates.

Results

Among 3,184 children enrolled, 28% were < 5 years of age on 9/11; 34%, 5–11 years; and 39%, 12–17 years. Forty-five percent had a report of dust cloud exposure on 9/11. Half (53%) reported at least one new or worsened respiratory symptom, and 5.7% reported new asthma diagnoses. Before 9/11, age-specific asthma prevalence in enrolled children was similar to national estimates, but prevalence at interview was elevated among enrollees < 5 years of age. Dust cloud exposure was associated with new asthma diagnosis (adjusted odds ratio = 2.3; 95% confidence interval, 1.5–3.5).

Conclusions

Asthma prevalence after 9/11 among WTCHR enrollees < 5 years of age was higher than national estimates, and new asthma diagnosis was associated with dust cloud exposure in all age groups. We will determine severity of asthma and persistence of other respiratory symptoms on follow-up surveys.     

Adverse Effects of Methylmercury: Environmental Health Research Implications

Background

The scientific discoveries of health risks resulting from methylmercury exposure began in 1865 describing ataxia, dysarthria, constriction of visual fields, impaired hearing, and sensory disturbance as symptoms of fatal methylmercury poisoning.

Objective

Our aim was to examine how knowledge and consensus on methylmercury toxicity have developed in order to identify problems of wider concern in research.

Data sources and extraction

We tracked key publications that reflected new insights into human methylmercury toxicity. From this evidence, we identified possible caveats of potential significance for environmental health research in general.

Synthesis

At first, methylmercury research was impaired by inappropriate attention to narrow case definitions and uncertain chemical speciation. It also ignored the link between ecotoxicity and human toxicity. As a result, serious delays affected the recognition of methylmercury as a cause of serious human poisonings in Minamata, Japan. Developmental neurotoxicity was first reported in 1952, but despite accumulating evidence, the vulnerability of the developing nervous system was not taken into account in risk assessment internationally until approximately 50 years later. Imprecision in exposure assessment and other forms of uncertainty tended to cause an underestimation of methylmercury toxicity and repeatedly led to calls for more research rather than prevention.

Conclusions

Coupled with legal and political rigidity that demanded convincing documentation before considering prevention and compensation, types of uncertainty that are common in environmental research delayed the scientific consensus and were used as an excuse for deferring corrective action. Symptoms of methylmercury toxicity, such as tunnel vision, forgetfulness, and lack of coordination, also seemed to affect environmental health research and its interpretation.     

Respiratory and allergic health effects of dampness, mold, and dampness-related agents: a review of the epidemiologic evidence

Objectives

Many studies have shown consistent associations between evident indoor dampness or mold and respiratory or allergic health effects, but causal links remain unclear. Findings on measured microbiologic factors have received little review. We conducted an updated, comprehensive review on these topics.

Data sources

We reviewed eligible peer-reviewed epidemiologic studies or quantitative meta-analyses, up to late 2009, on dampness, mold, or other microbiologic agents and respiratory or allergic effects.

Data extraction

We evaluated evidence for causation or association between qualitative/subjective assessments of dampness or mold (considered together) and specific health outcomes. We separately considered evidence for associations between specific quantitative measurements of microbiologic factors and each health outcome.

Data synthesis

Evidence from epidemiologic studies and meta-analyses showed indoor dampness or mold to be associated consistently with increased asthma development and exacerbation, current and ever diagnosis of asthma, dyspnea, wheeze, cough, respiratory infections, bronchitis, allergic rhinitis, eczema, and upper respiratory tract symptoms. Associations were found in allergic and nonallergic individuals. Evidence strongly suggested causation of asthma exacerbation in children. Suggestive evidence was available for only a few specific measured microbiologic factors and was in part equivocal, suggesting both adverse and protective associations with health.

Conclusions

Evident dampness or mold had consistent positive associations with multiple allergic and respiratory effects. Measured microbiologic agents in dust had limited suggestive associations, including both positive and negative associations for some agents. Thus, prevention and remediation of indoor dampness and mold are likely to reduce health risks, but current evidence does not support measuring specific indoor microbiologic factors to guide health-protective actions.     

Childhood Asthma and Environmental Exposures at Swimming Pools: State of the Science and Research Recommendations

Objectives

Recent studies have explored the potential for swimming pool disinfection by-products (DBPs), which are respiratory irritants, to cause asthma in young children. Here we describe the state of the science on methods for understanding children’s exposure to DBPs and biologics at swimming pools and associations with new-onset childhood asthma and recommend a research agenda to improve our understanding of this issue.

Data sources

A workshop was held in Leuven, Belgium, 21–23 August 2007, to evaluate the literature and to develop a research agenda to better understand children’s exposures in the swimming pool environment and their potential associations with new-onset asthma. Participants, including clinicians, epidemiologists, exposure scientists, pool operations experts, and chemists, reviewed the literature, prepared background summaries, and held extensive discussions on the relevant published studies, knowledge of asthma characterization and exposures at swimming pools, and epidemiologic study designs.

Synthesis

Childhood swimming and new-onset childhood asthma have clear implications for public health. If attendance at indoor pools increases risk of childhood asthma, then concerns are warranted and action is necessary. If there is no such relationship, these concerns could unnecessarily deter children from indoor swimming and/or compromise water disinfection.

Conclusions

Current evidence of an association between childhood swimming and new-onset asthma is suggestive but not conclusive. Important data gaps need to be filled, particularly in exposure assessment and characterization of asthma in the very young. Participants recommended that additional evaluations using a multidisciplinary approach are needed to determine whether a clear association exists.     

Symptoms and Medication Use in Children with Asthma and Traffic-Related Sources of Fine Particle Pollution

Background

Exposure to ambient fine particles [particulate matter ≤ 2.5 μm diameter (PM_2.5)] is a potential factor in the exacerbation of asthma. National air quality particle standards consider total mass, not composition or sources, and may not protect against health impacts related to specific components.

Objective

We examined associations between daily exposure to fine particle components and sources, and symptoms and medication use in children with asthma.

Methods

Children with asthma (n = 149) 4–12 years of age were enrolled in a year-long study. We analyzed particle samples for trace elements (X-ray fluorescence) and elemental carbon (light reflectance). Using factor analysis/source apportionment, we identified particle sources (e.g., motor vehicle emissions) and quantified daily contributions. Symptoms and medication use were recorded on study diaries. Repeated measures logistic regression models examined associations between health outcomes and particle exposures as elemental concentrations and source contributions.

Results

More than half of mean PM_2.5 was attributed to traffic-related sources motor vehicles (42%) and road dust (12%). Increased likelihood of symptoms and inhaler use was largest for 3-day averaged exposures to traffic-related sources or their elemental constituents and ranged from a 10% increased likelihood of wheeze for each 5-μg/m³ increase in particles from motor vehicles to a 28% increased likelihood of shortness of breath for increases in road dust. Neither the other sources identified nor PM_2.5 alone was associated with increased health outcome risks.

Conclusions

Linking respiratory health effects to specific particle pollution composition or sources is critical to efforts to protect public health. We associated increased risk of symptoms and inhaler use in children with asthma with exposure to traffic-related fine particles.     

Toward identifying the next generation of superfund and hazardous waste site contaminants

Background

This commentary evolved from a workshop sponsored by the National Institute of Environmental Health Sciences titled “Superfund Contaminants: The Next Generation” held in Tucson, Arizona, in August 2009. All the authors were workshop participants.

Objectives

Our aim was to initiate a dynamic, adaptable process for identifying contaminants of emerging concern (CECs) that are likely to be found in future hazardous waste sites, and to identify the gaps in primary research that cause uncertainty in determining future hazardous waste site contaminants.

Discussion

Superfund-relevant CECs can be characterized by specific attributes: They are persistent, bioaccumulative, toxic, occur in large quantities, and have localized accumulation with a likelihood of exposure. Although still under development and incompletely applied, methods to quantify these attributes can assist in winnowing down the list of candidates from the universe of potential CECs. Unfortunately, significant research gaps exist in detection and quantification, environmental fate and transport, health and risk assessment, and site exploration and remediation for CECs. Addressing these gaps is prerequisite to a preventive approach to generating and managing hazardous waste sites.

Conclusions

A need exists for a carefully considered and orchestrated expansion of programmatic and research efforts to identify, evaluate, and manage CECs of hazardous waste site relevance, including developing an evolving list of priority CECs, intensifying the identification and monitoring of likely sites of present or future accumulation of CECs, and implementing efforts that focus on a holistic approach to prevention.     

A Review of Advocate–Scientist Collaboration in Federally Funded Environmental Breast Cancer Research Centers

Background

The Long Island Breast Cancer Study Project was the first federally funded study of environmental causes of breast cancer. Although advocates were expected to participate in this study, the details of their participation were not adequately clarified in project guidelines, which resulted in confusion over their role in the project. The Breast Cancer and Environment Research Centers (BCERCs) are funded by the National Institute of Environmental Health Sciences and the National Cancer Institute; these centers continue to conduct research into environmental links to breast cancer and to clarify advocate–scientist guidelines for collaboration.

Objectives

Practitioners in community-based participatory research (CBPR) are grappling with how to improve CBPR projects for all groups involved in breast cancer and environmental studies. The ever-growing body of literature on CBPR elaborates on a number of factors that make CBPR particularly challenging, specifically regarding partnerships between advocate and scientific communities. This study draws on CBPR principles to evaluate advocate–scientist collaboration in the BCERCs.

Methods

We conducted surveys at BCERC annual meetings in 2005 and 2007 and 11 in-depth open-ended interviews with key stakeholders such as primary investigators within the centers to assess the perceptions of the advocates and scientists regarding collaboration between advocates and scientists who were engaged in CBPR studies.

Results

We found that although participatory guidelines were a focus of BCERCs, underlying differences between advocates and scientists with regard to paradigms of scientific inquiry, priorities, and desired outcomes need to be addressed for more effective collaboration to take place.

Conclusion

Our findings contribute to the broader CBPR literature by highlighting the role of underlying assumptions that may hinder the collaborative process and suggest the need for continued assessment research into participatory research projects on breast cancer and the environment.     

From Good Intentions to Proven Interventions: Effectiveness of Actions to Reduce the Health Impacts of Air Pollution

Background

Associations between air pollution and a multitude of health effects are now well established. Given ubiquitous exposure to some level of air pollution, the attributable health burden can be high, particularly for susceptible populations.

Objectives

An international multidisciplinary workshop was convened to discuss evidence of the effectiveness of actions to reduce health impacts of air pollution at both the community and individual level. The overall aim was to summarize current knowledge regarding air pollution exposure and health impacts leading to public health recommendations.

Discussion

During the workshop, experts reviewed the biological mechanisms of action of air pollution in the initiation and progression of disease, as well as the state of the science regarding community and individual-level interventions. The workshop highlighted strategies to reduce individual baseline risk of conditions associated with increased susceptibility to the effects of air pollution and the need to better understand the role of exposure duration in disease progression, reversal, and adaptation.

Conclusion

We have identified two promising and largely unexplored strategies to address and mitigate air pollution–related health impacts: reducing individual baseline risk of cardiovascular disease and incorporating air pollution–related health impacts into land-use decisions.     

Breaking Patterns of Environmentally Influenced Disease for Health Risk Reduction: Immune Perspectives

Background

Diseases rarely, if ever, occur in isolation. Instead, most represent part of a more complex web or “pattern” of conditions that are connected via underlying biological mechanisms and processes, emerge across a lifetime, and have been identified with the aid of large medical databases.

Objective

We have described how an understanding of patterns of disease may be used to develop new strategies for reducing the prevalence and risk of major immune-based illnesses and diseases influenced by environmental stimuli.

Findings

Examples of recently defined patterns of diseases that begin in childhood include not only metabolic syndrome, with its characteristics of inflammatory dysregulation, but also allergic, autoimmune, recurrent infection, and other inflammatory patterns of disease. The recent identification of major immune-based disease patterns beginning in childhood suggests that the immune system may play an even more important role in determining health status and health care needs across a lifetime than was previously understood.

Conclusions

Focusing on patterns of disease, as opposed to individual conditions, offers two important venues for environmental health risk reduction. First, prevention of developmental immunotoxicity and pediatric immune dysfunction can be used to act against multiple diseases. Second, pattern-based treatment of entryway diseases can be tailored with the aim of disrupting the entire disease pattern and reducing the risk of later-life illnesses connected to underlying immune dysfunction. Disease-pattern–based evaluation, prevention, and treatment will require a change from the current approach for both immune safety testing and pediatric disease management.     

Exposure and Effect Assessment of Aerosolized Red Tide Toxins (Brevetoxins) and Asthma

Background

In previous studies we demonstrated statistically significant changes in reported symptoms for lifeguards, general beach goers, and persons with asthma, as well as statistically significant changes in pulmonary function tests (PFTs) in asthmatics, after exposure to brevetoxins in Florida red tide (Karenia brevis bloom) aerosols.

Objectives

In this study we explored the use of different methods of intensive ambient and personal air monitoring to characterize these exposures to predict self-reported health effects in our asthmatic study population.

Methods

We evaluated health effects in 87 subjects with asthma before and after 1 hr of exposure to Florida red tide aerosols and assessed for aerosolized brevetoxin exposure using personal and ambient samplers.

Results

After only 1 hr of exposure to Florida red tide aerosols containing brevetoxin concentrations > 57 ng/m³, asthmatics had statistically significant increases in self-reported respiratory symptoms and total symptom scores. However, we did not see the expected corresponding changes in PFT results. Significant increases in self-reported symptoms were also observed for those not using asthma medication and those living ≥ 1 mile from the coast.

Conclusions

These results provide additional evidence of health effects in asthmatics from ambient exposure to aerosols containing very low concentrations of brevetoxins, possibly at the lower threshold for inducing a biologic response (i.e., toxicity). Consistent with the literature describing self-reported symptoms as an accurate measure of asthmatic distress, our results suggest that self-reported symptoms are a valuable measure of the extent of health effects from exposure to aerosolized brevetoxins in asthmatic populations.     

Social Science Collaboration with Environmental Health

Background

Social science research has been central in documenting and analyzing community discovery of environmental exposure and consequential processes. Collaboration with environmental health science through team projects has advanced and improved our understanding of environmental health and justice.

Objective

We sought to identify diverse methods and topics in which social scientists have expanded environmental health understandings at multiple levels, to examine how transdisciplinary environmental health research fosters better science, and to learn how these partnerships have been able to flourish because of the support from National Institute of Environmental Health Sciences (NIEHS).

Methods

We analyzed various types of social science research to investigate how social science contributes to environmental health. We also examined NIEHS programs that foster social science. In addition, we developed a case study of a community-based participation research project in Akwesasne in order to demonstrate how social science has enhanced environmental health science.

Results

Social science has informed environmental health science through ethnographic studies of contaminated communities, analysis of spatial distribution of environmental injustice, psychological experience of contamination, social construction of risk and risk perception, and social impacts of disasters. Social science–environmental health team science has altered the way scientists traditionally explore exposure by pressing for cumulative exposure approaches and providing research data for policy applications.

Conclusions

A transdisciplinary approach for environmental health practice has emerged that engages the social sciences to paint a full picture of the consequences of contamination so that policy makers, regulators, public health officials, and other stakeholders can better ameliorate impacts and prevent future exposure.

Citation

Hoover E, Renauld M, Edelstein MR, Brown P. 2015. Social science collaboration with environmental health. Environ Health Perspect 123:1100–1106; http://dx.doi.org/10.1289/ehp.1409283     

Evaluation of Spatial Relationships between Health and the Environment: The Rapid Inquiry Facility

Background

The initiation of environmental public health tracking systems in the United States and the United Kingdom provided an opportunity to advance techniques and tools available for spatial epidemiological analysis integrating both health and environmental data.

Objective

The Rapid Inquiry Facility (RIF) allows users to calculate adjusted and unadjusted standardized rates and risks. The RIF is embedded in ArcGIS so that further geographical information system (GIS) spatial functionality can be exploited or results can be exported to statistical packages for further tailored analyses where required. The RIF also links directly to several statistical packages and displays the results in the GIS.

Methods

The value of the RIF is illustrated here with two case studies: risk of leukemia in areas surrounding oil refineries in the State of Utah (USA) and an analysis of the geographical variation of risk of esophageal cancer in relation to zinc cadmium sulfide exposure in Norwich (United Kingdom).

Results

The risk analysis study in Utah did not suggest any evidence of increased relative risk of leukemia, multiple myeloma, or Hodgkin’s lymphoma in the populations around the five oil-refining facilities but did reveal an excess risk of non-Hodgkin’s lymphoma that might warrant further investigation. The disease-mapping study in Norwich did not reveal any areas with higher relative risks of esophageal cancer common to both males and females, suggesting that a common geographically determined exposure was unlikely to be influencing cancer risk in the area.

Conclusion

The RIF offers a tool that allows epidemiologists to quickly carry out ecological environmental epidemiological analysis such as risk assessment or disease mapping.     

Qualitative Environmental Health Research: An Analysis of the Literature, 1991–2008

Background

Recent articles have advocated for the use of qualitative methods in environmental health research. Qualitative research uses nonnumeric data to understand people’s opinions, motives, understanding, and beliefs about events or phenomena.

Objective

In this analysis of the literature, I report the use of qualitative methods and data in the study of the relationship between environmental exposures and human health.

Data sources

A primary search on ISI Web of Knowledge/Web of Science for peer-reviewed journal articles dated from 1991 through 2008 included the following three terms: qualitative, environ*, and health. Inclusion and exclusion criteria are described.

Data extraction

Searches resulted in 3,155 records. Data were extracted and findings of articles analyzed to determine where and by whom qualitative environmental health research is conducted and published, the types of methods and analyses used in qualitative studies of environmental health, and the types of information qualitative data contribute to environmental health.

Data synthesis

Ninety-one articles met inclusion criteria. These articles were published in 58 different journals, with a maximum of eight for a single journal. The results highlight a diversity of disciplines and techniques among researchers who used qualitative methods to study environmental health, with most studies relying on one-on-one interviews. Details of the analyses were absent from a large number of studies. Nearly all of the studies identified increased scientific understanding of lay perceptions of environmental health exposures.

Discussion and conclusions

Qualitative data are published in traditionally quantitative environmental health studies to a limited extent. However, this analysis demonstrates the potential of qualitative data to improve understanding of complex exposure pathways, including the influence of social factors on environmental health, and health outcomes.     

Personal exposures to traffic-related air pollution and acute respiratory health among Bronx schoolchildren with asthma

Background

Previous studies have reported relationships between adverse respiratory health outcomes and residential proximity to traffic pollution, but have not shown this at a personal exposure level.

Objective

We compared, among inner-city children with asthma, the associations of adverse asthma outcome incidences with increased personal exposure to particulate matter mass ≤ 2.5 μm in aerodynamic diameter (PM_2.5) air pollution versus the diesel-related carbonaceous fraction of PM_2.5.

Methods

Daily 24-hr personal samples of PM_2.5, including the elemental carbon (EC) fraction, were collected for 40 fifth-grade children with asthma at four South Bronx schools (10 children per school) during approximately 1 month each. Spirometry and symptom scores were recorded several times daily during weekdays.

Results

We found elevated same-day relative risks of wheeze [1.45; 95% confidence interval (CI), 1.03–2.04)], shortness of breath (1.41; 95% CI, 1.01–1.99), and total symptoms (1.30; 95% CI, 1.04–1.62) with an increase in personal EC, but not with personal PM_2.5 mass. We found increased risk of cough, wheeze, and total symptoms with increased 1-day lag and 2-day average personal and school-site EC. We found no significant associations with school-site PM_2.5 mass or sulfur. The EC effect estimate was robust to addition of gaseous pollutants.

Conclusion

Adverse health associations were strongest with personal measures of EC exposure, suggesting that the diesel “soot” fraction of PM_2.5 is most responsible for pollution-related asthma exacerbations among children living near roadways. Studies that rely on exposure to PM mass may underestimate PM health impacts.     

A Personal Perspective on the Initial Federal Health-Based Regulation to Remove Lead from Gasoline

Objective

This article describes the personal experience and perspective of the authors, who had primary responsibility for drafting the initial health-based regulation limiting lead content of gasoline during the early 1970s while employed by the U.S. Environmental Protection Agency (EPA).

Data source

Information used by the U.S. EPA in developing the initial health-based regulation limiting lead content of gasoline in December 1973 and studies documenting the impact of that and subsequent actions.

Data extraction

Among the lessons learned from this experience is the importance of having input from independent scientists to the regulatory decision-making process. This also demonstrates the critical role of independent peer-reviewed research, such as that supported by the National Institutes of Health, as well as research conducted by scientists from the Centers for Disease Control and Prevention, in delineating the consequences of lead exposure in the population.

Data synthesis

Removal of lead from gasoline in the United States has been described as one of the great public health achievements of the 20th century, but it almost did not happen. The experience of the authors in developing this regulation may be helpful to others involved in developing health-based regulatory policy in the future.

Conclusion

The initial U.S. EPA health-based regulation to remove lead from gasoline is clearly an example where science successfully affected public policy. The leadership of the U.S. EPA at that time deserves much credit for establishing an atmosphere in which this was possible.