Research Plan Summary/Abstract The Michigan PBB Cohort is the longest running, multi-generational cohort study of a widespread environmental contamination event in the United States. More than 40 years ago, millions of Michiganders ate farm products contaminated with polybrominated biphenyls (PBB), a chemical flame retardant. This cohort of approximately 7,500 individuals includes those who ate the contaminated food, chemical plant workers, their children, and their grandchildren. Extensive health, exposure, and biological samples have been collected from these individuals for four decades. While systematic updates of this cohort ceased in 2003 due to paucity of infrastructure funds, the Emory team pursued hypothesis-driven research with NIH funding. Research based on the Michigan PBB Cohort has demonstrated relationships between exposure to PBB and many health outcomes, including thyroid conditions, breast cancer risk, lower Apgar scores in children, reproductive health in daughters, and genitourinary abnormalities in sons. Current NIH-funded research includes innovative approaches involving genomics, epigenomics, exposomics and metabolomics across multiple generations as well as a randomized clinical trial of a nutritional aid hypothesized to speed elimination of PBB. The PBB research team has been exceedingly productive, contributing over 150 scientific communications. The PBB cohort has served as a source of data and biospecimens for eight NIH R01 grants, two EPA STAR grants, an NIH R03, and an NIH R21, reflecting the important scientific questions that can be addressed with this cohort. Importantly, for the last 6 years, the affected Michigan community has become a partner in the PBB research efforts, dedicating their time and resources to support the continuation of this work that is so meaningful to their family's and community's health. To assure this valuable cohort is accessible and useful for future studies and data sharing, with this R24 support we plan to update the vital status of the entire cohort and to develop a state-of-the-art data management and analytic platform. This platform will enable linkage of over 40 years of follow-up data and thousands of biospecimens. Using state of the art web-based communication, we will develop web portals to enable broad sharing of the cohort resources with three important stakeholder groups: the scientific community, cohort members (to access their own data), and local public health agencies. This infrastructure grant will support research addressing the long-term impact of exposure to brominated flame retardants, which continues to be found in the blood of the vast majority of Americans - making the intensive study of this unique cohort relevant to all Americans.

The Michigan PBB Registry was established in order to study the health of thousands of people exposed to brominated flame retardants as a result of the largest agricultural disaster in US history. Previous research by this team has shown significant health effects associated with exposure to polybrominated biphenyls (PBB) including earlier menarche, increased risk of miscarriages and lower estrogen levels among women, and more urogenital problems among men. Over the past few years, Emory researchers have conducted over a dozen community meetings throughout Michigan, collaborated with community partners, shared research findings with the community, responded to community needs, and sought community input for future research plans. This proposed study, collaboratively developed by scientists, community partners, and public health officials, addresses several major concerns expressed by the PBB community. Specifically, affected individuals have expressed interest in a possible treatment to remove PBBs from their bodies, concern about heritable effects from PBB on their children and grandchildren, continuing health concerns beyond those related to reproduction, and frustration that local health-care providers seem unaware of the statewide PBB exposure and/or its possible health effects. To address these concerns, the proposed study has four specific aims. The first is to evaluate the utility of nutritional supplement, a non-absorbable artificial fat, as a potential means of accelerating the elimination of PBB by conducting a randomized double-blind trial. The second aim will explore the heritability of changes in the epigenome associated with PBB exposure by studying 25 families across three generations. The epigenome of parents, their children, and their grandchildren will be examined to determine if epigenetic patterns associated with direct exposure to PBB of parents are apparent in the children and grandchildren. Aim three will address community concerns regarding additional health effects beyond reproductive outcomes. Participants, including 575 new enrollees, will complete health questionnaires and provide serum samples for analysis to determine if PBB exposure is associated with neurodegenerative diseases, joint pain/disorder, cancer, immune function and liver/pancreatic problems. If any of the self-identified adverse outcomes are associated with PBB exposure, additional funding will be sought to further explore these associations. Finally, the public health action plan will seek t raise environmental health awareness in Michigan. Educational programs will be developed for healthcare providers, policy-makers, and citizens to increase local capacity to address exposure concerns.

Humans are exposed to chemicals such as brominated flame retardants (BFR) at unprecedented levels, and a wide variety of health effects are attributed to such exposures. However, the biological mechanisms that link exposures to its consequences remain unknown. An industrial accident in the 1970's exposed over 4000 individuals in rural Michigan to polybrominated biphenyl (PBB), a BFR that was present in the food supply for years prior to detection and management. Health effects are still evident in these individuals and their children. Because this population has been assessed regularly since the exposure, it is an ideal group in which to examine the molecular mechanisms that contribute to susceptibility, vulnerability and health effects. The project goals are to: 1) identify the genetic variants that associate with the rate of PBB elimination over time, 2) identify epigenetic patterns that associate with PBB exposure, 3) integrate genetic and epigenetic datasets and identify complex gene-environment relationships in PBB exposed individuals and 4) evaluate the contribution PBB-associated genetic and epigenetic factors to endocrine-related consequences of exposure. We will leverage data generated as part of past and ongoing studies in the Michigan Polybrominated Biphenyl Cohort and characterize genetic and epigenetic variation in 2 PBB-exposed cohorts, a discovery cohort of 500 subjects exposed through living on or eating food from contaminated farms and a replication cohort of 200 subjects exposed through work at the Michigan Chemical Company that produced PBBs. This research will produce the largest and most comprehensive genetic dataset in subjects exposed to PBBs. We anticipate that this study will provide insight into how genetic variants and the environment interact in relation to PBB exposure and its health effects. We also anticipate the results of this study will be informative for studies of BFRs and other endocrine disrupting compounds with similar chemical properties.

Biomonitoring has become a common tool in assessing exposure to a variety of chemicals including persistent organic pollutants (POP). POPs are typically measured in blood serum, usually requiring a 10 mL whole blood draw or more. Because of the invasiveness of sample collection, infants and children are not typically included in studies evaluating POPs exposure or health effects. Dried blood spots (DBS) are collected from all neonates at birth and are archived by the state health department for a number of years. DBS represent a potential matrix for biomonitoring of POPs. Distinct advantages of using DBS include: (1) they can be easily collected from participant or non-medical personnel; (2) DBS cards are inexpensive compared to blood collection supplies; (3) each state has an archive of DBS from all children born in the state; (4) DBS can be easily mailed from the field to laboratory using standard postal services; and (5) they can be used to collect infant or child blood samples. Despite their advantages, few laboratories have attempted to use them as a matrix for biomonitoring studies. We propose to develop and validate a sensitive, selective and precise method for measuring polybrominated biphenyls, polychlorinated biphenyls and organochlorine pesticides in a single DBS. We will measure these chemicals in 50 neonate DBS samples archived from 1970-1980 in Michigan, a state that experienced a contamination event in the early 1970s which resulted in widespread exposure to certain POPs. These measurements will help us to understand if DBS archived for over 40 years are useful for historic testing purposes and will help us pinpoint the exact year the contamination occurred. In addition, we plan to field test the prospective collection of paired serum and DBS samples shipped to the laboratory on dry ice (overnight) and via USPS, respectively, to determine if they correlate without appreciable bias. This research will not only inform our current cohort study in Michigan but also other studies seeking cost-effective sample collection strategies that can also be used on infants and children.

Concerns have been raised in the lay and scientific communities that various synthetic chemicals showing hormonal or anti-hormonal properties in vitro and in wildlife populations are causing adverse health effects in humans by interfering with normal endocrine function. A number of the structurally similar halogenated organics belong to this category. Because these chemicals are widespread in the environment and accumulate in human and animal tissues, any associations with adverse health effects could have far reaching public health implications. The Michigan PBB cohort consists of over 4,000 individuals exposed to brominated flame retardants as the result of an industrial accident and has been successfully followed for nearly thirty years. This cohort presents a unique opportunity to determine whether exposure to halogenated organics is associated with endocrine disruption and to evaluate the impact across generations. In the grand tradition of epidemiology we seek to learn as much as we can from an unfortunate "natural" experiment. This applications follows two previous studies of endocrine sensitive endpoints among cohort members conducted by the same team of investigators. In the proposed study we focus on the offspring of cohort members where we have found the greatest evidence of endocrine disruption. Specific Aim 1 continues our assessment of the consequences of in utero exposure among males. We previously found that sons of highly exposed women experienced an increased risk of genitourinary conditions and slower growth and pubertal development. Specific Aim 2 addresses endocrine-sensitive endpoints among female offspring following evidence that highly exposed girls have an earlier age at menarche and an increased risk of miscarriages. In Specific Aim 3 we seek to characterize the cross-generational transfer of brominated flame retardants and Specific Aim 4 is an exploration of interdisciplinary approaches to understand biological mechanisms of multi-generational endocrine disruption and gene/environmental interactions.