Research & Scholarship
Research in the Department of Environmental Health spans epidemiology, toxicology, urban environmental health, and public policy. We have highlighted a few studies below.
Exposure to PBDEs
Polybrominated diphenyl ethers (PBDEs) are used as fire retardants in common products, including furniture and electronics. Average levels in people and environmental concentrations have increased over the last several decades and are highest in the USA. We are one of the leading groups investigating human exposure to these compounds. Using biomonitoring and environmental sampling, we have shown that concentrations of PBDE levels in people are related to both diet and PBDE concentrations in dust. We have further shown that inhalation exposure can be increased by the “Pigpen effect,” the tendency of people to be surrounded by a cloud of dust. To learn more, please visit the CIREEH PBDE page.
Photo: In award-winning research, doctoral candidate Joe Allen used x-ray fluorescence (XRF) to link PBDE concentrations in house dust to bromine levels in consumer products.
EH faculty: McClean and Webster
Environmental Contaminants & Immunotoxicology
Humans receive significant ambient daily exposures to multiple environmental contaminants, including aromatic hydrocarbons (by-products of combustion) and phthalate esters (plasticizers used in manufacturing PVC). These types of contaminants induce a suicide program (i.e., apoptosis) in developing B lymphocytes (i.e., the antibody-producing cells) within the bone marrow microenvironment. We want to know how synthetic chemicals override the naturally occurring cellular processes to induce death. We investigate multiple processes in the cell that may be altered by these chemicals, including how chemicals interact with receptors that can change the genetic program of the cell, such as the aryl hydrocarbon receptor (AhR) and the peroxisome proliferator activated receptors (PPAR). Further, as real-world exposures such as those at Superfund sites typically involve complex chemical mixtures, we want to investigate how chemicals within the mixtures may interact to enhance deleterious effects. Understanding these pathways is important because loss of B lymphocytes could potentially impair the ability to mount an immune response to infections. On the other side of the coin, our understanding of death pathways and mixture interactions potentially may be put to use in the development of new chemotherapeutics.
Photo: Dr. Schlezinger at work in the lab.
EH Faculty: Schlezinger, Sherr, and Webster
Spatial Epidemiology & Exposure Assessment
The Spatial Epidemiology group is developing and applying methods for mapping case-control and cohort epidemiologic data while taking into account known risk factors and residential history. We are also studying the potential benefits and problems of studies that use combinations of individual and group-level (“ecologic”) data. Finally, we are using geographic information systems (GIS) in assessing exposure. To learn more, please visit the CIREEH Spatial Epidemiology page.
Figure: The map above shows breast cancer risk as a function of residential location twenty years prior to diagnosis. Blue areas have decreased risk compared to average, red areas have elevated risk.
EH faculty: Vieira and Webster
The Sherr Lab
The Sherr laboratory is located in SPH’s Department of Environmental Health and occupies 3,300 square feet of newly renovated laboratory space in the Housman Research Building within the Boston University Medical Campus and School of Medicine. The laboratory employs state-of-the-art cellular and molecular technologies to research three specific areas of basic and applied science:
- Mechanisms through which environmental chemicals suppress the immune system. The “Apoptosis Team” in Dr. Sherr’s laboratory investigates the detrimental effects of entire classes of common environmental pollutants on development of B lymphocytes in the bone marrow. These cells, like all 8 types of blood cells, are exquisitely sensitive to environmental compounds such as polycyclic aromatic hydrocarbons (PAH). Dr. Sherr’s laboratory has demonstrated that the PAH toxicity in the bone marrow is mediated by induction of a cell suicide program known as “apoptosis” and results in the loss of specific essential components of the immune system.
- Molecular signaling leading to environmental carcinogen-induced and spontaneous breast cancers. The “Breast Cancer Team” evaluates the molecular mechanisms through which common environmental chemicals (e.g., PAH) induce and promote breast cancer. Among other important findings, the team has shown that a cellular receptor which binds PAHs malfunctions in breast cancer cells (the “aryl hydrocarbon receptor/AhR”) and thereby drives tumor cell growth and development into aggressive, invasive cancers, regardless of whether or not the cancer was induced by environmental chemicals. These results suggest that targeting this receptor is a viable strategy for preventing or treating breast cancer regardless of its cause.
- Development of vaccines for the treatment of cancer and primary amyloidosis. The “Cancer Immunotherapy Team” has developed several candidate vaccines that could be used against a variety of cancers associated with environmental chemical exposures including breast cancer, myeloma, and AL amyloidosis. One immunization strategy involves delivery of the vaccine directly to the immune system (lymph nodes) by injection of vaccine-bearing lymphocytes which migrate to appropriate lymphoid organs (see picture). These “Trojan horse” vaccines have been shown in the Sherr Lab to be extremely efficient at inducing immune responses to cancer vaccines.
EH Faculty: Schlezinger and Sherr
Occupational Safety & Health Policy
Injury- and illness-reporting systems provide data used to prioritize efforts to prevent occupational injuries and illnesses. Reported injury rates also are used to measure the success or failure of prevention efforts. Yet, studies over the last two decades have concluded that injuries are underreported in both systems. Researchers in the department have used capture-recapture analysis to measure the amount of underreporting in the two most commonly used injury-reporting sources in the US: state workers’ compensation data and the Bureau of Labor Statistics Survey of Occupational Injuries and Illnesses. Initial findings in 7 states suggest that many injuries go unreported and many workers eligible for disability benefits do not receive them.
Another group of studies describes and measures the economic and social impacts of workplace injuries and illnesses on workers and their families and, in addition, determines the adequacy of benefits paid to people with disabling injuries. Current work in this area will measure impacts on workers’ earnings, on whether they remain in the labor force, and on long-term total disability.
EH faculty: Boden
Although toxicology studies usually test one chemical at a time, we are exposed to mixtures. We are using laboratory experiments and mathematical modeling to investigate the action of simple chemical mixtures: additivity, synergism, and antagonism. Such information can help with both understanding the risks posed by chemicals and the mechanisms by which they act. We are also comparing the ways that toxicologists and epidemiologists assess interaction of exposures. To learn more, please visit the CIREEH Interactions page.
Figure: Model for the response (E) to mixtures of compounds A and B, from doctoral candidate Greg Howard’s award-winning work.
EH faculty: Schlezinger and Webster
The Boston University Superfund Research Program (BU SRP) takes an interdisciplinary approach to studying how environmental exposure to hazardous substances affects human and environmental health. There are nine projects supported by five cores in the SRP at Boston University. The research focuses on common contaminants and on exposures that result from improperly managed waste disposal. It includes epidemiologic studies and laboratory-based research that seeks to reveal the mechanisms by which common chemicals affect processes of reproduction and development in both humans and wildlife. The program is supported by the National Institute of Environmental Health Sciences (NIEHS), as part of the National Institutes of Health (NIH). To learn more, please visit the BU SRP website.
EH faculty: Heiger-Bernays, Ozonoff (Director), Scammell, Schlezinger, Sherr, Vieira, and Webster
Exposure Biology Research Group (EBRG)
The Exposure Biology Research Group (EBRG), directed by Dr. Michael McClean, is an interdisciplinary research group in SPH’s Department of Environmental Health. Our primary research focus is on the use of biological markers to assess environmental and occupational exposures via multiple pathways with respect to exposure-related disease.
The EBRG consists of a research coordinator, eight research assistants, five doctoral students, and space within the 3,500-square-foot Environmental Health Laboratory—shared by Dr. McClean and three other faculty members in the Department of Environmental Health. Our laboratory is equipped with a range of direct reading field instruments (Innov-X Portable XRF Analyzer, TSI Sidepaks, personal air sampling pumps, etc.) as well as equipment necessary to collect, process, and store environmental and biological samples in support of extensive field investigations. Several of the research staff are trained and experienced phlebotomists.
EH faculty: McLean, Webster, Ozonoff