Ranch Hand Health Study

To assess the potential health effects from exposure to Agent Orange, the Air Force is conducting the second phase of the Ranch Hand Health Study, and a large medical study of army veterans is underway at the Centers for Disease Control. The comparison groups for these studies are non-exposed military personnel. 

J. E. Michalek and N. S. Ketchum, April 25,2002, Diabetes and Dioxin in Air Force Health Study Participants, typescript, 9 pp., prepared for the Department of Health and Human Services advisory committee to the Ranch Hand study. 

The authors of the Ranch Hand Study, the Department of Health and Human Services committee that reviewed the study before publication,44 the reviewers and editors of the journal Epidemiology that published the study, and a scientist who wrote a comment about the Ranch Hand study for Epidemiology found no support for an association between herbicide exposure and any birth defect. Only the IOM committee identified the biologically implausible association. 

A health study of Vietnam veterans involved in Operation Ranch Hand indicated an association between high initial and current serum 2,3,7,8-TCDD levels and increased erythrocyte sedimentation (Wolfe et al. 1995), and an earlier study by Wolfe et al. (1985) indicated an increase in mean corpuscular volume however, these changes were minor and were not observed in the 1991 follow-up (USAF 1991). Higher serum 2,3,7,8-TCDD levels were also associated with positive dose-response trends for increases in white blood cell and platelet levels. 

A health study in Vietnam veterans involved in Operation Ranch Hand found no liver diseases linked to... 

A health study of Vietnam veterans involved in operation Ranch Hand did not find any correlations between clinically significant immunological alterations and serum 2,3,7,8-TCDD levels (USAF 1991). 

The effects of 2,3,7,8-TCDD exposure on gonadal function (production of germ cells and secretion of sex hormones) has not been extensively investigated. A health study in Vietnam veterans involved in Operation Ranch Hand found a significant association between decreased testicular size and serum... 

In an earlier study by Wolfe et al. (1985) of Air Force personnel involved in Operation Ranch Hand, a significant increase in the number of reported neonatal deaths (no additional details provided), as compared to a comparison group of Air Force military employees not stationed in Vietnam, was observed. The incidence of major defects, prematurity, learning disabilities, or infant deaths was not increased in the Ranch Hand personnel. A significant increase in the incidence of minor health effects such as birth marks, rashes, and neonatal jaundice was reported by the Ranch Hand veterans. It should be noted that the pregnancy outcomes were self-reported, and this finding was not corroborated by the follow-up study (Wolfe et al. 1995) which used birth certificates, medical records, and death certificates to assess possible relationships between paternal exposure to 2,3,7,8-TCDD and developmental effects in offspring. 

In 1983 an epidemiological study of some 1200 Air Force personnel who had been involved in Operation Ranch Hand found that there was no increased mortality, and a study released in 1984 by the Center for Disease Control found no clear correlation between Agent Orange exposure and birth defects in the children of the exposed person." However, a law suit brought on behalf of an estimated 20000 veterans against the manufacturers of Agent Orange was settled out of court in 1984, and in 1986 it was announced that a New Jersey study showed that veterans exposed to 2,4,5-T had levels of a dioxin, TCDD, well above the 20 parts per million normally considered a threat to health." ... 

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