The McLeod Report makes a number of assertions about the extent to which Australian and New Zealand troops may have been exposed to herbicide spraying. Without exception these assertions are unsubstantiated and can be shown to have no credibility. In at least one case, an assertion appears to have been nothing more than a fabrication by the authors of the McLeod Report.

The McLeod Report claims that there is "only one recorded case where ANZAC troops were in an area where they could have been exposed to aerial spraying." (1) The authority for this claim is given as the Advisory Committee on the Health of Veterans Children 1999. This is a New Zealand government-sponsored report, which undertook no primary source research whatsoever. It does not cite any source for this exposure claim. (2) So the Advisory Committee has made an unsubstantiated claim, which can, at best, be only be based on secondary source material, and the McLeod Report has recycled that unsubstantiated claim. This could be the beginning of a dangerous cycle in which a series of government-sponsored reports simply cite each other, while no actual research is ever done. This cycle must be stopped.

My own original research has provided documentary evidence that most, if not all, ANZAC troops were in areas where they could have been exposed to aerial spraying. (3)

The McLeod Report gives no explanation of the exposure model involved in this unsubstantiated claim. It appears, however, that the authors of the McLeod Report expect Australian and New Zealand Vietnam veterans to be able to place themselves directly under a herbicide flight in order to prove exposure. This exposure model is ludicrous.

Because it accepts a link between Agent Orange and health effects, the United States Department of Veterans Affairs has put considerable effort into developing an exposure model. In 1989, the United States Secretary for Veterans Affairs, Ed Derwinski, commissioned Admiral Elmo Zumwalt Junior to produce a report on the association between adverse health effects and exposure to Agent Orange. (4) Admiral Zumwalt reported on the 5^th of May, 1990. (5) Extraordinary though it may seem, the McLeod Report, reporting more than eleven years later, does not cite the Zumwalt Report in its research. In fact, it makes no mention of the Zumwalt Report whatsoever.

Admiral Zumwalt made two recommendations on exposure. The first suggests that the veteran should have been "within 20 kilometers and 30 days of a known sprayed area," or "at fire base perimeters or brown water operations where there is reason to believe Agent Orange spraying has occurred." (6) Admiral Zumwalt had serious doubts about even this generous exposure model:

Under this alternative compensation would not be provided for those veterans whose exposure came from TCDD by way of the food chain; silt runoff from sprayed areas into unsprayed waterways; some unrecorded US or allied Agent Orange sprayings; inaccurately recorded sprayings; or sprayings whose wind drift was greater than 20 kilometers." (7)

As a result of his concerns, Admiral Zumwalt offered a second exposure model:

Any Vietnam veteran or child of a Vietnam veteran who experiences a TCDD-like health effect shall be presumed to have a service-connected disability. This alternative is admittedly broader than the first, and would provide benefits for some veterans who were not exposed to Agent Orange and whose disabilities are not presumably truly service-connected. Nevertheless, it is the only alternative that will not unfairly preclude receipt of benefits by a TCDD exposed Vietnam veteran. (8)

To summarize, Admiral Zumwalt's recommended exposure models were: first, a veteran should have been within 20 kilometres and 30 days of a sprayed area; second, if the veteran or child of a veteran has a dioxin-related illness, proof of Vietnam service is proof of exposure. These options were presented to Secretary Derwinski. He chose the second, more generous option. As a result, the United States Department of Veterans Affairs now accepts as its exposure model that proof of Vietnam service is proof of exposure. (9)

The United States exposure model is clearly relevant to the Australian and New Zealand Vietnam experience. It is scarcely conceivable that the authors of the McLeod Report failed to take the trouble to access the US DVA web site or any of its Agent Orange publications. Even to raise the subject of exposure without informing its readers of the model in use in the US raises serious questions about the integrity of the McLeod Report.

The McLeod Report claims that the exposure levels of the United States Air Force personnel who served on Operation Ranch Hand were "likely to be in the order of 1000 times the exposure of Australian and New Zealand veterans." (10) No substantiation is given for this claim. This is a complete fabrication. No study has ever compared the levels of exposure of Ranch Hand veterans and Australian and New Zealand veterans. If the authors of the McLeod Report believe such a study exists, then let them cite it. Otherwise, it can only be assumed that this is a figure they have simply invented.

The McLeod Report states that Agent Orange was "frequently contaminated by small amounts of dioxin." (11) No substantiation is offered for any part of this assertion. No explanation is given for the claim that Agent Orange was "frequently", as opposed to "always", contaminated by dioxin, and no explanation is given for the claim that the dioxin contamination consisted of "small amounts."

A study published in the leading scientific journal Nature has analysed the amount of herbicide sprayed during the Vietnam War. (12) It finds that the amount of herbicide sprayed has been underestimated by more than seven million litres, "in particular with heavily dioxin-contaminated herbicides." It also finds that the amount of dioxin sprayed during the war is almost double previous estimates. (13)

For many years it has been assumed that the mean level of dioxin in Agent Orange was 3 parts per million. This assumption appears to have been based merely on an estimate, rather than a scientific measurement. The authors of the Nature article subjected this assumption to scientific analysis for the first time, and found it to be extremely low. The article finds that an average value "closer to 13 p.p.m. may be more realistic." (14) This makes a mockery of the McLeod Report's estimation of dioxin levels in Agent Orange as "small amounts."

Evidence has recently emerged to prove that, as Vietnam veterans have always suspected, indirect exposure to herbicides and pesticides in Vietnam is as relevant an issue as direct exposure. A study published in the Journal of Occupational and Environmental Medicine found a marked elevation of dioxin in blood samples taken from residents of the Vietnamese city of Bien Hoa, more than thirty years after the last herbicide flight. (15) Bien Hoa is the capital city of Bien Hoa Province, in which Anzac forces frequently operated. It was the site of the base camp for the first contingent of Anzac forces in 1965-66.

The title of the study is "Recent Dioxin Contamination from Agent Orange in Residents of a Southern Vietnam City." Its authors are an international team of eight, led by the American, Arnold Schecter.

The authors of the study are careful to emphasize that it is only 2,3,7,8-TCDD, the dioxin found in Agent Orange, and not any other type of dioxin, that was found to be elevated in these blood samples.

The dioxin levels are staggering. Comparison samples were taken from residents of North Vietnam, where no herbicides were sprayed during the war. North Vietnamese dioxin levels were found to be 2 parts per trillion. Dioxin levels in the Bien Hoa samples were up to 271 p.p.t., or 135 times the level of the North Vietnamese samples. The average dioxin level of the Bien Hoa residents was 69.65 p.p.t., or 35 times the level of the North Vietnamese comparison group. (16)

Dioxin levels were raised, even in residents new to the area, and in children born as recently as 1988, long after Agent Orange spraying ended. The study found elevated dioxin levels in fish caught in Bien Hung Lake and the Song Dong Nai River, and in soil samples taken from the site of the former Bien Hoa airbase, the early headquarters of Operation Ranch Hand. It is worth repeating that these dioxin levels were found thirty years after the last Agent Orange flight.

These results are backed up by other studies in Vietnam. (17) In a new development, an article entitled "Food as a Source of Dioxin Exposure in the Residents of Bien Hoa City, Vietnam" has appeared in the August 2003 edition of the Journal of Occupational and Environmental Medicine. (18) This study finds:

Clearly, food, including duck, chicken, some fish, and a toad, appears responsible for elevated TCDD in residents of Bien Hoa City, even though the original Agent Orange contamination occurred 30-40 years before sampling. (19)

These studies provide the clearest proof yet that the dioxin in Agent Orange stays in the environment, pollutes the food chain, and contaminates humans regardless of whether or not they were directly sprayed. Any assessment of exposure that fails to take into account this evidence of indirect exposure can have no credibility.