A publication of Work On Waste USA, Inc., 82 Judson, Canton, NY 13617 315-379-9200 July 1993
Prepared by the Committee to Review the Health Effects in Vietnam Veterans of Exposure to Herbicides,
Division of Health Promotion and Disease Prevention, National Academy of Sciences Institute of Medicine. Released on July 27, 1993. Published by the National Academy Press, 2101 Constitution Avenue, N.W., Washington, D.C. 20418.
Tel: 1-800-624-6242 or 202-334-3313. Available for $85 plus $4 shipping. Report is approx. 750 pages.
Report links disease to Herbicides; calls for new studies of exposed Vietnam Veterans
Summary of Findings from the reports Executive Summary, page 6:
Sufficient Evidence of Association. Evidence is sufficient to conclude that there is a positive association. That is, a positive association has been observed between herbicides and the outcome in studies in which change, bias, and confounding could be ruled out with reasonable confidence....There is sufficient evidence of an association between exposure to herbicides and the following health outcomes: Soft tissue sarcoma, Non-Hodgkins lymphoma, Hodgkins disease, Chloracne, Porphyria cutanea tarda (in genetically susceptible individuals).
Limited/Suggestive Evidence of an Association. Evidence is suggestive of an association between herbicides and the outcome, but is limited because chance, bias, and confounding could not be ruled out with confidence. For example, at least one high-quality study shows a positive association, but the results of other studies are inconsistent. There is limited/suggestive evidence of an association between exposure to herbicides and the following health outcomes: Respiratory cancers (lung, larynx, trachea), Prostate cancer, Multiple myeloma.
Inadequate/Insufficient Evidence to Determine Whether an Association Exists. The available studies are of insufficient quality, consistency, or statistical power to permit a conclusion regarding the presence or absence of an association. For example, studies fail to control for confounding, have inadequate exposure assessment, or fail to address latency. There is inadequate or insufficient evidence to determine whether an association exists between exposure to herbicides and the following health outcomes: Hepatobiliary cancers, Nasal/nasopharyngeal cancer, Bone cancer, Female reproductive cancers (breast, cervical, uterine, ovarian), Renal cancer, Testicular cancer, Leukemia, Spontaneous abortion, Birth defects, Neonatal/infant death and stillbirths, Low birthweight, Childhood cancer in offspring, Abnormal sperm parameters and infertility, Cognitive and neuropsychiatric disorders, Motor/coordination dysfunction, Peripheral nervous systems disorders, Metabolic and digestive disorders (diabetes, changes in liver enzymes, lipid abnormalities, ulcers), Immune system disorders (immune modulation and autoimmunity), Circulatory disorders, Respiratory disorders.
Limited/Suggestive Evidence of No Association. Several adequate studies, covering the full range of levels of exposure that human beings are known to encounter, are mutually consistent in not showing a positive association between exposure to herbicides and the outcome at any level of exposure. A conclusion of no association is inevitably limited to the conditions, level of exposure, and length of observation covered by the available studies. In addition, the possibility of a very small elevation in risk at the levels of exposure studied can never be excluded. There is limited/suggestive evidence of no association between exposure to herbicides and the following health outcomes: Skin cancer, Gastrointestinal tumors (stomach cancer, pancreatic cancer, colon cancer, rectal cancer),Bladder cancer, Brain tumors.
The following are excerpts from a news release from the National Academy of Sciences Institute of Medicine issued on July 23, 1993, (embargoed to July 27) announcing the report.
The U.S. Congress asked the National Academy of Sciences Institute of Medicine [IOM] to conduct a comprehensive review of available scientific information regarding the health effects of exposure to Agent Orange and other herbicides used in Vietnam. The report is the product of the IOM committees work, begun in 1992. The study was sponsored by the U.S. Department of Veterans Affairs. The Institute of Medicine is a private, non-profit organization that provides health policy advice under a congressional charter granted to the National Academy of Sciences...The committees report specifically focuses on Agent Orange and other herbicides used in Vietnam, some of which contained dioxin, an unintended byproduct of the manufacturing process. ...Most of the evidence the committee reviewed about adverse health effects came from studies of people who were exposed as a result of their jobs or from industrial accidents. These types of exposures often were at high levels and for long periods of time. Getting a clear picture of the health risks for Vietnam veterans is not so straightforward, the committee said, because the levels of exposure were extremely wide ranging. Indeed, while most veterans probably had lower exposure levels, some may have experienced levels as high as that of occupational or agricultural exposures. What is uncertain is how many veterans may have been exposed to those higher levels and who those individuals are. We simply do not know the degree of risk for Vietnam veterans, said committee vice chair David Tollerud, director of occupational and environmental medicine, University of Pittsburgh Graduate School of Public Health. We do feel, however, that enough information exists to allow studies to be done that would lead to a better understanding of the risk that veterans face for contracting diseases related to herbicide exposure in Vietnam...The committee examined more than 230 epidemiological studies in detail on a range of health problems and their possible association with herbicides. It found sufficient evidence of a statistical association between exposure to herbicides or dioxin and soft tissue sarcoma, non-Hodgkins lymphoma, and Hodgkins disease. The committee also found sufficient evidence of an association between herbicides or dioxin and chloracne and PCT [Porphyria cutanea tarda]. Chloracne is a specific acne-like skin disorder; PCT is a liver disorder characterized by thinning and blistering of the skin. The category of sufficient evidence represented the strongest link the committee made between adverse health effects and exposure to herbicides, including Agent Orange or dioxin...In reviewing the literature, the committee found that exposure assessment was the weakest element in most epidemiological studies of veterans. While some studies show a link between adverse health effects and herbicides or dioxin, there are few data indicating which individuals may have received high exposures during service in Vietnam. The evidence about exposure during the war suggests that Vietnam veterans as a group had substantially lower exposure to herbicides and dioxins than the subjects in many occupational studies, the committee said. Veterans who were participants in Operation Ranch Hand -- the extensive spraying of some 19 million gallons of herbicide over 3.6 million acres of South Vietnam from airplanes -- are an exception to this pattern, however, because of their direct involvement in the spraying missions. But the committee also said that, among the approximately 3 million Vietnam veterans, there may be some former ground troops not directly involved in the spraying who were exposed to herbicides at levels associated with adverse health effects. The committee emphasized that it may be possible to develop better exposure measures for Vietnam veterans by relying on less formal sources of historical information than have been used in the past. Previous studies have relied primarily on the carefully recorded information on aerial spraying in Operation Ranch Hand and on blood tests for dioxin, but these measures may not reflect the full range of exposures of Vietnam veterans to herbicides. The committee urged that a non-government organization be commissioned to develop and test new methods of evaluating herbicide exposure in Vietnam veterans. These new methods would draw on historical reconstructions and include information on the spraying that occurred around base camps and other areas which could have led to higher human exposures, the committee said. Important information could be gained from historical records of ground and perimeter spraying, herbicide shipments to various military bases, and knowledge of the type of terrain and foliage typical of the locations sprayed and the military mission of the troops located there...It also urged continued follow-up of the Ranch Hand veterans and its comparison group, and recommended that members of the Army Chemical Corps also be studied for adverse health effects from exposure. Studies should be done by an independent agency, noting that such an independent body could do much to satisfy the publics concern about impartiality and scientific credibility...
The Committee who wrote the report for the Institute of Medicine:
Harold Fallon (chair), Dean, School of Medicine, U. of Alabama, Birmingham; David Tollerud (vice-chair), Director, Occupational and Environmental Medicine, U. of Pittsburgh, PA; Norman Breslow, Professor, Dept. of Biostatistics, U. of Washington, Seattle; Jesse Berlin, Research Asst. Professor of Biostatistics in Medicine, U. of PA School of Medicine, Philadelphia; Karen Bolla, Asst. Professor, Dept. of Neurology, Johns Hopkins U. School of Medicine, Baltimore; Graham Colditz, Assoc. Prof. of Medicine, Harvard Medical School, Boston; Christopher Goetz, Director, Dept. of Neurologic Sciences, Rush-Presbyterian-St. Lukes Medical Center, Chicago; Norbert Kaminski, Asst. Prof, Dept. of Pharmacology and Toxicology, Medical College of Virginia, Richmond; David Kriebel, Assoc. Prof, Dept. of Work Environment, U. of Massachusetts, Lowell; Karle Mottet, Prof., Dept. of Pathology and Environmental Health, U. of Washington School of Medicine, Seattle; Alfred Neugut, Assoc. Prof, Dept. of Medicine and School of Public Health, Columbia U. College of Physicians and Surgeons, N.Y. City; William Nicholson, Prof., Mount Sinai School of Medicine, N.Y. City; Andrew Olshan, Asst.. Prof, Dept. of Epidemiology, School of Public Health, U. of North Carolina, Chapel Hill; Kathleen Rodgers, Assoc. Prof, Dept. of Obstetrics and Gynecology, U. of Southern Calif. School of Medicine, Los Angeles; Nancy Sprince, Assoc. Prof, Robert Wood Johnson Medical School, U. of Medicine & Dentistry of N.J., Piscataway. Clifford Weisel, Asst. Professor, Robert Wood Johnson Medical School, U. of Medicine and Dentistry of N.J., Piscataway. Institute of Medicine staff: Michael Stoto, project director; Cynthia Abel, research associate