A new study published in the January 2005 Environmental Health Perspectives uncovers a link between autoimmunity and asbestos exposures. Researchers at the University of Montana Center for Environmental Health Sciences evaluated 50 residents from Libby, Montana, a town polluted by asbestos as a result of decades of mining vermiculite that had contaminated the mine, processing sites, and many homes, buildings, and properties in the town. It was found that these residents were much more likely to have a class of autoantibodies (proteins that the body mistakenly unleashes against its own tissue) in their blood than a control group from a nearby unpolluted town. In fact, researchers found that these autoantibodies, known as antinuclear antibodies (ANAs), occurred 28.6 percent more frequently in the Libby patient group than in the control group. Presence of these ANAs is often found in people whose immune systems may be predisposed to developing autoimmune disease.
Based on the results of this small-scale study, the University of Montana researchers intend to embark on a larger-scale study to determine the extent to which the increased ANA levels have resulted in actual autoimmune disease among the Libby population.
While the hereditary aspect of autoimmune disease is well known, the environmental triggers have been less well understood until recently, according to Betty Diamond, M.D., Chair of AARDA Scientific Advisory Board and Professor of Medicine and Biology, Columbia University College of Physicians and Surgeons. "This small, but provocative, study is a first step in helping the biomedical research community to identify and better understand one potential environmental trigger for autoimmune disease," said Dr. Diamond. "We look forward to hearing the results of the planned larger-scale study."
Dr. Diamond commented that this study, coupled with a recent Johns Hopkins University study linking excessive iodine ingestion to a specific autoimmune disease, Hashimoto thyroiditis, "highlights the need for more research to determine whether a number of suspected environmental factors trigger autoimmunity."
An environmental study commissioned by AARDA and prepared by the Johns Hopkins Center for Autoimmune Disease Research and the PAHO/WHO Collaborating Center for Autoimmune Disorders identifies opportunities for future directions. In their report, the authors state, "Although it may be difficult to determine an unequivocal relationship between an environmental exposure, potentially at a low dose, and a disease that takes years to develop, these types of studies are critical to calling our attention to the possible role that a xenobiotic [an antibiotic chemical substance not produced by the body and, thus, foreign to it] may play in human disease."
The report, supported by a grant from the National Institute of Environmental Health Sciences, concludes: "While great strides have been made in recent years toward understanding the role of environmental factors in the development and exacerbation of autoimmune diseases, this report reveals a skewing of these research efforts. The majority of emphasis has been placed on metal and estrogen-induced autoimmune disease." The committee suggests, ". . . there is much work still to be done, many important findings still to be discovered, and much room for growth in this field."
Certainly the study at the University of Montana Center for Environmental Health Sciences underscores the serious need for further medical research examining the potential range of environmental factors and the role they may play in the development of autoimmune diseases.
