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The article presents information on the U.S. herbicide program which was implemented during the Vietnam War. It is stated that the program aroused several controversies over the usage of herbicides in military operations. The health hazards caused due to herbicides, specially the effect of Agent Orange on the U.S. veterans of Vietnam was the matter of concern. It is reported that recently the U.S. Air Force declassified few pages of the book "Operation Ranch Hand: The Air Force and Herbicides in Southeast Asia 1961-71," written by Major William A. Buckingham.

Using validated models and methods routinely employed by pesticide regulatory agencies, the absorbed dosages of Agent Orange (AO) herbicide contaminant 2,3,7,8-tetrachlorodibenzo- p -dioxin (TCDD) were estimated for mixer/loaders, applicators, and individuals in the vicinity of applications of AO by C-123 aircraft during the Vietnam War. Resulting dosages of TCDD were then transformed to estimates of adipose residues, and compared to population biomonitoring of known mixer/loaders and applicators as well as ground troops in Vietnam and civilians in the U.S. Results demonstrate that mixer/loaders and applicators had the greatest exposures and their measured residues of TCDD in adipose were consistent with the estimated exposures. Further, the potentially exposed ground troops, including those who could have been directly sprayed during aerial defoliation, had measured adipose residues that were consistent with those in civilian U.S. populations with no defined source of exposure exposures and both of those cohorts had orders of magnitude less exposure than the mixer/loaders or applicators. Despite the availability of validated exposure modeling methods for decades, the quantitative TCDD dose estimates presented here are the first of their kind for the Vietnam conflict. [ABSTRACT FROM AUTHOR]

Highlights: [•] We measured PCDDs, PCDFs and PCBs in serum of Vietnam War veterans (US Air Force). [•] Median TCDD levels in 2002 were higher in Ranch Hands than in comparison veterans. [•] Levels of other PCDDs, PCDFs and noPCBs did not differ substantially between groups. [•] Levels of moPCBs did not differ substantially between Ranch Hands and comparisons. [•] We also compared results to those from comparable age groups studied in NHANES. [ABSTRACT FROM AUTHOR]

During the Vietnam War, the United States military declared war not just on Vietnamese peoples, but also on nature itself. Operation Ranch Hand served as the U.S. military's answer to the Vietnamese Communist appropriation of the natural world into their war plans, as U.S. planes dumped nearly twenty million gallons of chemical herbicides on Vietnamese fields and forests. Examining and comparing the military and ecological effects of Ranch Hand, this essay assesses the military success of chemical defoliation by looking at military appraisals and early U.S. scientific studies of defoliated areas. Planners expected defoliation to provide a distinct military advantage and frequently made claims that they were trading trees for lives – environmental destruction ostensibly saved the lives of U.S. servicemen. Instead, defoliation's military effects proved very ambiguous and the use of defoliants should be considered a failure in some ways. In trying to characterise defoliation as either a military success or failure, the essay also questions what it means for a piece of technology to succeed or fail and ultimately concludes that the answer to that question depends on the goals for its use, not the technology itself [ABSTRACT FROM AUTHOR]

By exploring tactical and strategic uses of chemical agents beyond Agent Orange and the other 'Rainbow Herbicides' used as part of Operation Ranch Hand during the Vietnam War, this essay seeks to fill a gap in our under- standing of the chemical war waged by the United States in South-east Asia, and to make a contribution to the growing body of literature devoted to the intersections of military and environmental history. Taking seriously the roles played by both human and non-human actors, it explores how the White House and Pentagon continually attempted, unsuccessfully, to impose more stringent forms of control over southern Vietnam. Herbicidal warfare and the use of forest fire as a military weapon were simply two more failed attempts among many to impose control on a nation, a people, and a landscape - indeed, on nature itself - all of which refused to accept the dictates of American power just as stubbornly as American policymakers refused to accept the limitations of that power. [ABSTRACT FROM AUTHOR]

In 1979, the U.S. Air Force announced that an epidemiologic study would be undertaken to determine whether the Air Force personnel involved in Operation Ranch Hand–the program responsible for herbicide spraying in Vietnam–had experienced adverse health effects as a result of that service. In January 1982 the Air Force Health Study (AFHS) protocol was approved and the 20 year matched cohort study consisting of independent mortality, morbidity and reproductive health components was initiated. This controversial study has been criticized regarding the study''s potential scientific limitations as well as some of the administrative aspects of its conduct. Now, almost 30 years since the implementation of the AFHS and nearly a decade since the final follow up examinations, an appraisal of the study indicates that the results of the AFHS do not provide evidence of disease in the Ranch Hand veterans caused by their elevated levels of exposure to Agent Orange. [Copyright &y& Elsevier]

The article assesses ecocide and the environmental justice movement in relation to the book "Herbicidal Warfare: The Ranch Hand Project in Vietnam," by Paul Cecil. The author participated in the U.S. defoliation program Operation Ranch Hand during Vietnam War. The recognition of the environmental toxic burdens facing communities of color has reportedly driven the U.S. movement. The ideology confronting Cecil about the use and proximity to chemicals is said to unite communities affected by toxic burdens such as Agent Orange victims in Vietnam.

The authors studied immune response and exposure to 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (dioxin) among veterans of Operation Ranch Hand, the US Air Force unit responsible for the aerial spraying of herbicides in Vietnam from 1962 to 1971. A comparison group of Air Force veterans who served in Southeast Asia but were not involved in spraying herbicides was included. The authors studied delayed-type hypersensitivity skin test responses to Candida albicans, mumps, Trichophyton, and a bacterial antigen made from lysed Staphylococcus aureus. Lymphocyte measurements included total lymphocyte counts; T-cell (CD3, CD4, CD5, and CD8), B-cell (CD20), and NK-cell (CD16 and CD56) subsets; and expression of the activation antigen CD25 on CD3 T cells. The authors quantitated the serum concentrations of immunoglobulin (lg)A, IgG, and IgM; examined sera for the presence of monoclonal immunoglobulins (M proteins); and looked for a broad range of autoantibodies (rheumatoid factor, antinuclear antibody, smooth muscle autoantibody, mitochondrial autoantibody, parietal cell autoantibody, and thyroid microsomal autoantibodies). They measured the level of dioxin in 1987 or 1992, extrapolated the result to the time of service in Vietnam, and assigned each veteran to one of four exposure categories: Comparison and three Ranch Hand groups (Background, Low, or High). Overall, the authors found no evidence of a consistent relation between dioxin exposure category and immune system alteration. Am J Epidemiol 1999; 149:1038–46. [ABSTRACT FROM PUBLISHER]

We studied cancer prevalence and exposure to 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (dioxin) in veterans of Operation Ranch Hand, the Air Force unit responsible for the aerial spraying of herbicides in Vietnam from 1962 to 1971. A comparison group of Air Force veterans who served in Southeast Asia during the same period and who were not involved with spraying herbicides was included. Comparison veterans were matched to Ranch Hand veterans on age, race, and military occupation. We measured dioxin in 1987 or 1992, extrapolated the result to the time of service in Southeast Asia, and assigned each Ranch Hand veteran to Background, Low, or High exposure categories. This study had low power to detect an effect for specific or rare cancers. The risk of cancer at sites other than the skin within 20 years of service was increased in the Low (odds ratio (OR) = 3.4, 95% confidence interval (Cl) 1.5–8.0) and High (OR = 2.7, 95% Cl 0.9–8.0) categories, but the pattern was inconsistent with another study, suggesting that the excess risk may not have been caused by dioxin exposure. Overall, we found no consistent evidence of a dose-response gradient and no significant increase in cancer risk in the High dioxin exposure category, the subgroup of greatest a priori interest. Am J Epidemiol 1999; 149:630–9. [ABSTRACT FROM PUBLISHER]

The article discusses the chemical warfare used by U.S. armed forces and their allies during the Vietnam War between 1961 and 1975 in Vietnam. The author reports on twentieth century American military strategies regarding the use of herbicides and chemicals in war. Chemicals used by the U.S. included DDT, Malation, tear gases, and Agent Orange, especially during Operation Ranch Hand from 1962 to 1971. The chemicals were used to target food-producing areas, forested areas abutting strategic military areas, and communications routes.

The article presents a case study of the frequency of nasopharyngeal cancer in 1400 veterans including dioxin-exposed patients and a control group of veterans not exposed to dioxin-poisoning at Central Military Hospital 108 in Hanoi, Vietnam. Dioxin poisoning was the result of the use of Agent Orange by the U.S. military as part of Operation Ranch Hand from 1962 to 1971 during the Vietnam War. The study found that dioxin is a cancer-causing agent.

The article focuses on the health impact of the Vietnam War as a result of chemical warfare, especially the use of Agent Orange by the U.S. military as part of Operation Ranch Hand from 1961 to 1971. It confirms that both Vietnamese soldiers and civilians were exposed to toxic levels of dioxin and consequently have developed a wide range of dioxin-related diseases such as various cancers, infertility, high rates of abnormal pregnancies, and congenital defects such as cerebral palsy, hydrocephalus, and various skeletal deformities.

The article focuses on the link between birth defects in Vietnamese children and the herbicide Agent Orange, which was sprayed by the U.S. military on crops in Vietnam during the Vietnam War in the 1960s-1970s. Vietnam claims that parental exposure at the time of spraying of the herbicide is resulting in children being born with defects. Meanwhile, scientists are planning to revive the health study of the U.S. veterans involved in Operation Ranch Hand, in which 95% of the herbicide was sprayed on Vietnam. The Vietnamese are claiming compensation for the injuries caused due to the herbicide, asking the U.S. to sue the companies that supplied the herbicide to the U.S. military. The U.S. on its part has agreed to clear the areas affected by the agent.

Begun in 1982, the Air Force Health Study (AFHS) has assessed the mortality of veterans of Operation Ranch Hand, the unit responsible for aerially spraying herbicides in Vietnam. A comparison group of other Air Force veterans involved with aircraft missions in Southeast Asia during the same period, but not involved with spraying herbicides, was included in the study. Among 18,082 veterans, this report examined whether attendance at AFHS physical examinations from 1982 to 1999 played a role in mortality experience and potential lengthening of life relative to veterans who did not attend. The years of potential life lost for 1,173 veterans who died before age 65 was calculated. No statistically significant difference in risk of death was found from all causes, cancer, or circulatory disease between attendees and nonattendees. No evidence was found to suggest that attending physical examinations decreased mortality or substantially lengthened life in AFHS participants. [ABSTRACT FROM AUTHOR]

US Air Force veterans of Operation Ranch Hand sprayed herbicides contaminated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in Vietnam from 1962 to 1971. Comparisons served in Southeast Asia (SEA) during the same time period but did not spray herbicides. Here we investigate a potential association between exposure to TCDD and prostate cancer. Data were available for 2516 veterans (1019 Ranch Hand and 1497 Comparison) who participated in at least one of six physical examinations starting in 1982 and had a measurement of serum TCDD. We assigned Ranch Hands to two exposure categories: Lower and Higher, based on their median 20-year cumulative TCDD level. In total, 81 Comparison and 59 Ranch Hand prostate cancers were identified between 1 January 1982 and 31 December 2003. We found no overall increase in the risk of prostate cancer in Ranch Hand veterans versus the Comparisons. There was a positive association in Ranch Hand veterans in the Higher TCDD category who served in SEA before 1969 (RR=2.27, 95% CI 1.11–4.66) when more contaminated herbicides were used, but the number of cases was small (n=15). A within-group comparison found that in Comparison veterans, time served in SEA was associated with an increased risk of prostate cancer (RR=2.18, 95% CI 1.27–3.76, >789 days versus ≤789 days). No increase in the risk of prostate cancer was observed within the Ranch Hand group in association with TCDD or time served in SEA. These analyses suggest that a longer service in SEA and exposures other than TCDD may have increased the risk of prostate cancer in Comparison veterans.Journal of Exposure Science and Environmental Epidemiology (2006) 16, 184–190. doi:10.1038/sj.jea.7500448; published online 27 July 2005 [ABSTRACT FROM AUTHOR]

Using multivariate statistical models, no significant relationship was found between the rate of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) elimination and the occurrence or time to onset of diabetes in 343 veterans of Operation Ranch Hand, the unit responsible for the aerial spraying of Agent Orange and other TCDD-contaminated herbicides during the Vietnam War. Without adjustment for age, body mass index, family history of diabetes, and smoking history, the time to onset of diabetes decreased and the risk of diabetes increased with a diminished elimination rate. However, after adjustment, diabetes time to onset and occurrence were not significantly associated with TCDD elimination. Analyses of covariance found no significant difference between the average elimination rates of diabetic and nondiabetic veterans, without or with adjustment for risk factors. To our knowledge, this is the only study to date to examine TCDD elimination and diabetes. [ABSTRACT FROM AUTHOR]

Using multiple m easurem ents from serum collected over 10 yr (1982, 1987, and 1992), we estimated the half-life of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in 213 veterans of Operation Ranch Hand, the Air Force unit responsible for the aerial spraying of Agent Orange in Vietnam. The potential influences of age, percent body fat, and changes in percent body fat on the half-life estimate were also examined. The mean decay rate of TCDD for these veterans is 0.0797 per year with 95% confidence interval 0.0727 to 0.0868 per year; the corresponding half-life estimate is 8.7 yr with 95% confidence interval 8.0-9.5 yr. Half-life increased significantly with increasing body fat, but not with age or relative changes in percent body fat. [ABSTRACT FROM AUTHOR]

The article offers information on the 30-day delay of the Agent Orange study in the U.S. Despite the government standards at hand, researchers found it difficult to get the study approved thus it is already in its 30-day delay. The research is geared in studying the possible effects of the defoliant Agent Orange and other combat factors on U.S. veterans of the Vietnam War. It is suggested that the present or the incoming administration should heed that advice by the National Academy of Sciences wherein they should go ahead with a much-delayed study of Agent Orange. With the new data and advances in geographical information systems, researchers could plug a significant gap in earlier epidemiological studies.

The article discusses the use of Agent Orange during the Vietnam War from 1961 to 1975. Agent Orange is a herbicide that contains dioxin. The United States military sprayed approximately 10 to 12 million gallons of Agent Orange in Vietnam during the war. Majority of the Agent Orange was sprayed from the Air Force C-123 aircraft during Operation Ranch Hand from 1962 to 1971. It was used against the enemies during the war. However, American soldiers were also affected by the herbicide. Many Vietnam war veterans point to the dioxin in Agent Orange as the cause of their maladies.

The article focuses on the exposure of 67-year-old former infantryman Larry Carlson regarding the use and storage of thousands of barrels of Agent Orange in Okinawa Island, Japan between 1965 and 1966. It says that the statement of Carlson has challenged the consistent denial of the U.S. government on the presence of Agent Orange in the area. It mentions that the chemicals are transported from Okinawa to South Vietnam to be sprayed over jungles and crops during the herbicidal warfare campaign against Viet Cong called "Operation Ranch Hand." Meanwhile, the Vietnam Red Cross has estimated that three million Vietnamese are affected by the dioxins contained in the herbicide after the war ended.

Reprints a table from the article 'Pharmacokinetics of 2,3,7,8-tetrachlorodibenzo-p-dioxin in Seveso Adults and Veterans of Operation Ranch Hand,' by Joel E. Michalek, James L. Pirkle, Larry L. Needham, Donald G. Patterson Jr., Samuel P. Caudill, Ram C. Tripathi and Paolo Mocarelli, published in a 2002 issue of the 'Journal of Exposure Analysis and Environmental Epidemiology.'