At a price: manufacturing Agent Orange in NZ?

Submitted by Noel Benefield on

Did Ivon Watkins Dow (IWD) manufacture Agent Orange in New Zealand during the Vietnam War? I do not remember the exact year media outlets started investigating the manufacture of Agent Orange in New Zealand but I know I had already developed a deep distrust of anything I read on Vietnam Veterans and Agent Orange in the media. Many journalists cut their teeth on this subject but there were few facts amongst the trillions of words published.

The only way I thought I could get to the facts was to carry out my own research.

In December 1966, the Military Assistance Command, Vietnam (MACV) advised the Commander-In-Chief, Pacific (CINCPAC) that the United States’ projected shortage of Agent Orange was of immediate operational concern to MACV, that the value of herbicide operations in Vietnam had been proved, and that a failure to obtain needed supplies would cause an unacceptable impact on military operations. MACV accordingly requested that the United States investigate the possibility of plant expansion or diversion of product from commercial uses to booster supplies.

Shortfall in supply

On 3 April 1967, The US military Business and Defence Services Administration (BDSA), who could exercise the 1950 Defence Production Act and compel production of war material, sent a directive to the Dow Chemical Co. (Dow). The BDSA noted that Dow’s “capacity for the production of Orange” was 93,000 gallons per month, and ordered it to deliver that entire capacity to the military.

It would have been apparent to Dow that this ‘war provisions’ order would have substantial implications on its domestic production of 245T products.

Dow supplied about a third of the Agent Orange used by the US military in South Vietnam at a cost of US$7 per gallon. Its New Zealand subsidiary, Ivon Watkins Dow (IWD) had estimated their cost at about NZ $6.50 per gallon, which was below the US production cost of NZ $7.40.

On 29 March 1967, Dow notified sales personnel and customers nationwide that no commercial 2,4,5-T herbicides would be available “for at least the balance of 1967” due to “military direct orders for the entire United States 2,4,5-T capacity.” It should not be surprising that IWD would see an opportunity to either contribute to the manufacture of “Agent Orange”, or assist in supplying 245T commercial products to fill a vacuum.

On the 12 July 1967, New Zealand’s Minister of Defence, after communication with Dan Watkins of IWD, rang the US Secretary of Defence informing him that IWD might be able to help meet the US military’s requirement “for something approaching 1 million gals of defoliants for use in South Vietnam”.

IWD had contact with the US Embassy commercial attaché who thought that IWD usual production of 20,000 gallons per year of 245T, although cheaper than US manufacture cost, was too small to attract interest. IWD approached the Minister of Industries and Commerce for assistance in obtaining raw materials, which would enable them to boost production to 80,000 gallons per year.

The Minister of Defence said he wanted maximum effort to assist in getting the material to South Vietnam. Officials investigated whether the Royal New Zealand Air Force (RNZAF) could fly large amounts (up to 10 tons) of defoliants to South Vietnam on a regular basis. After the Chief of Air Staff (CAS) indicated that RNZAF transport was unlikely, the government looked into other options, including HMNZS Endeavour and Air New Zealand commercial freighters. Formal confirmation from the CAS to the Minister of Defence of RNZAF inability to assist occurred on 14 July 1967.

On 20 July 1967, the US Secretary of Defence reported to New Zealand’s Minister of Defence on the results of a meeting with the US Embassy Commercial Secretary. It was acknowledged that a survey was conducted a year earlier on an “if we need” basis. The most likely source was Polymer Proprietary in Auckland who, using a Japanese supply of raw materials, could produce 500,000 gallons per year. The US Embassy confirmed that this information had been noted and they had received advice that it was not desired to proceed to take up this New Zealand supply.  

Given that IWD did not conduct any analysis of potential production capability until alerted in 1967, this may suggest that the US Embassy did not survey them in 1966. The US Commercial Secretary thought that 80,000 gallons would not be significant enough to attract interest.  The probable benchmark was the decision a year earlier not to proceed with a 500,000-gallon supply.

On 25 July 1967, the issue entered the public arena in a New Zealand Herald article: ‘May make chemicals’. Four days later, the US Embassy issued a rebuttal, denying they had taken part in any negotiations about defoliant production in New Zealand.

On 8 August 1967, the New Zealand Prime Minister said in Parliament that “the American Government was in no way interested in purchasing defoliants from New Zealand” and that “the Government had been in no way involved in the matter.” 

On the balance of the above evidence, it is apparent that IWD were aware of US military requirements and conducted an in-depth analysis of their ability to manufacture defoliants for South Vietnam. It is also apparent various Government ministers investigated potential assistance. In the end, it seems that a lack of suitable transport options, and IWDs inability to produce significant quantities of defoliant, curtailed any potential manufacturing deal between the US and NZ.

Regardless of the US Embassy denial, anti-war publication Vietnam Quote & Comment reported that IWD workers were claiming that a shipment was ready for dispatch.

The following year (1968), the number of acres spayed with defoliants in South Vietnam fell because of a shortage of supply of Agent Orange.

NZ connection

Allegations about the manufacturing of defoliants in New Zealand resurfaced during the 1980s.

On 13 March 1989, the Vietnam Veterans Association sent a fax to the government stating they had evidence about the manufacture of Agent Orange in New Zealand in the late 1960s for use in Vietnam. The basis of their evidence was a purported claim from a former NZ Defence attaché in Washington that he wrote reports to the United States Defence Department about the supply of Agent Orange. Additional evidence from former employees at IWD indicated that the company exported 245T to the United States and Thailand during this period.

As a result, the government deferred to a Select Committee of the Foreign Affairs and Defence Committee. They produced rebuttal evidence that the assistant attaché had not served in Washington during the period claimed, and that he “has not affirmed to the Ministry the statements attributed to him”. This included the claim that he had allegedly told the VVANZ in March 1989 that he had written reports on the matter, and had contact with Milt Hunt of IWD.

Although IWD admitted they did send 245T to the US in 1967-1968, they claimed these exports were in a form (iso octyl or butyoxy ethanol esters) unsuitable for the production of Agent Orange.

IWD produced a description of Agent Orange identical to that used at the Evatt Royal Commission in Australia and in United States Air Force (USAF) investigations. This description focused on Agent Orange as an n butyl ester version of 245T and 24D. No mention was made of Agent Orange II (iso octyl ester version) that had been used as an alternative by the US military in 1967-1968 to overcome the deficiencies in supply of n butanol used in the esterification of n butyl ester.

IWD stated that the ‘modest quantities’ sent to the US were for Millar Products and AmChem Products – chemical companies not identified with Agent Orange production in the US. They also claimed they did not send components of Agent Orange n butyl ester version or the blended product to their parent Dow Chemicals during the period.

The Select Committee’s report stated that, “No conclusive facts or evidence were provided to the committee to substantiate the claim that IWD manufactured the formulation of Agent Orange in New Zealand during the Vietnam War.”

The previously mentioned documentary evidence of an exploration to manufacture defoliants for the US military, from the files of the Secretary of Defence were not mentioned in the Select Committee report, nor did they appeared as amendments.

Peace campaigner Owen Wilkes, who reviewed the Committee’s finding during the 1990s, accused the Committee of not following up on the documentation, suggesting that, “An examination of the Select Committee files shows they actually were given more interesting information than their report indicates.”

The Ministry of External Relations and Trade assisted the Committee. Evidence presented by Statistics New Zealand derived from Customs declarations of increased exports of chemicals in tariff classifications. One could expect 245T/24D to have been included in these reports, which also identified the countries receiving these exports during 1967-1968.

Given the claim by IWD that it did not manufacture Agent Orange 1, nor send components to its parent or companies involved in US manufacture for the US military, it is possible that this increase reflected new sales opportunities created by the impact of the “war provisions” legislation on US manufacturers.

A spokesperson for the DSIR Chemistry Division told the Select Committee,

“It is an academic issue whether Agent Orange was actually exported from New Zealand for use in Vietnam. All production here would at the least, have aided diversion of material from other sources.’

The Committee refuted claims it had accepted hearsay evidence, stating that it “discounted all hear-say evidence, unsubstantiated claims and personal opinion it received”.

That hearsay evidence did indicate pressure on n butyl ester 245T supplies overseas, and in New Zealand, because of US military demand. Claims were also made of large shipments of chemicals dispatched from New Plymouth under extraordinary secrecy and unusual shipping/documentation procedures.

Shipments from New Plymouth

The issue of shipments from New Plymouth to the US Military would resurface again in the next century. Under the title ‘Agent Orange: We've buried it under New Plymouth’, Investigate magazine published an article in February 2001 on manufacture at IWD. The author claimed a former top official at New Plymouth's IWD chemical factory, who has proven his identity and executive ranking in documents, was the source of the information.

The informant claimed that he was on the management committee of IWD, and he had supported the plan to export Agent Orange.

“People who'd served in the armed forces made a strong case for the need to defoliate the jungle, because of the risk to servicemen from ambush or sniper fire from the undergrowth.”

The informant explained, "To avoid detection, we shipped the Agent Orange to South America - Mexico if I recall correctly - and it was on shipped to its final destination from there."

Shipments to Mexico would suggest that the US military at Gulfport was the final destination.

Evidence against this would be transport costs negating any gain from the small price difference between NZ manufacture and US costs.

Agent Orange was not a registered herbicide, and to produce sell or transport such chemicals across US borders would have been a severe violation of US Government regulations.

Alternatively, if DOW had been the final destination it would have had to notify the US Department of Defense that they were buying outside of the US as the procurement process involved the inspection of all facilities and product. There is no record to that effect.

The informant also made the claim, “Now at this time, in the late 1960s and early seventies, the government had given IWD the exclusive licence to manufacture those chemicals. We made all of the 2,4-D and 2,4,5-T that was produced in New Zealand. No one else was allowed to.”

Agricultural chemicals required registration under the Agricultural Chemicals Act 1959 until repealed in 1980. That Act applied to the 1960-70 period, and any company could register an agricultural chemical. There was no exclusive licence to manufacture.

According to the informant, “Agent Orange was made from two chemicals”. 2,4-D and 2,4,5,T. When they're apart, they are herbicides. Mixed together, they become Agent Orange.”

This statement identifies a lack of knowledge of Agent Orange. To obtain the greatest defoliant effect, the US military called for 98 percent esters of 245T/24D. This required a different manufacturing process than used for domestic products. A shortage of n butanol for ester manufacture reduced the availability of Agent Orange, and n butyl ester variants of 245T, for domestic use. This shortage also prompted the call for Agent Orange II iso octyl variant. The military specifications also called for less than 1 percent inert ingredients, which was not a factor for domestic products.

All 245T/24D combination domestic products made during this period were water-soluble. Agent Orange was a specific military oil soluble product.

The Investigate article reviewed some of the 1967 Defence documents but did not present any other evidence. 

Recent investigations

Later in this new century, the issue of manufacture at IWD resurfaced.

An October 2004 newspaper article headlined ‘Vets claim Government tried to export defoliants’, identified the Defence 1967 documents and the Investigate Magazine article, but no new evidence was presented.

This was to change on 9 January 2005 when the Sunday News newspaper published under the heading, ‘A bloody Scandal: The shameful kiwi trade that stayed under wraps…until now’.

As well as the 1967 Defence documents, the journalist referenced two affidavits on new evidence. One was from a port worker that helped load the last ship to leave Port Taranaki with 245T and 24D from IWD, the association being that because both phenoxy herbicides were included it must have been Agent Orange.

The other was hearsay evidence of an overheard conversation by a New Plymouth MP who claimed that he knew about the shipments to the US Military in the Philippines.

Statistics NZ data of the period did identify modest increased exports to the Philippines in the 1967-1968 year. But it also indicated increased exports to other Asian destinations and ‘one offs’ to countries such as South Africa, Canada and Jamaica.

The following day in the New Zealand Herald, the former port worker extended his clam stating, “it was stuff from IWD going up to the Philippines…going up that way, anyway”.

On 11 January 2005, another newspaper reported that DOW Agro Sciences believed the claims were false. The spokesperson said that the company had provided evidence to the 1990 inquiry of all existing documentation including export records, and that there was nothing new in the affidavits. He also said that the New Plymouth MP should ‘front up’ with the information he had.

On 12 January 2005, the New Zealand Herald reported under the heading ‘MP denies evidence of Agent Orange exports’.  The reporter reiterated Dow Agro Sciences denial that it ever made Agent Orange in New Zealand or supplied ingredients to the US military.

The New Plymouth MP was reported to have said that he had no evidence IWD had exported Agent Orange components. He said he had received reports from people in his electorate about the production, and exportation of ingredients, “I’ve had people contact me saying that they believe or that they remember, but no one has actually delivered evidence”.

That pretty much summed up what I had found.

Whilst ‘the absence of evidence is not the evidence of absence’, in this case in this case I am inclined to believe that yes, IWM investigated the possibility of covering the shortfall in supply of defoliants to the US military but it didn’t go ahead.

Was I more informed than the journalists were? Probably not.

But most interesting would be the answer to the question: Who picked up the Japanese supply of Trichlorophenol?


Noel Benefield


Submitted by Barron on Saturday, 10 March 2018 - 5:39am


The mixture known as Agent Orange was designed by ICI UK around 1950 and used successfully in the Malayan Emergency for clearing roadsides and crop destruction. The USAF after testing many combinations at Elgin AFB Florida settled on this particular mixture. It is wrong to say a manufacturer "Made" Agent Orange as it is merely a mixture of two broadleaf weedkillers that have been sold over the counter since 1949. Dow NZ made 2,4,5T for the NZ market and used in large amounts by the gorse sprayers of Nth Canterbury and Marlborough. All the applicators were tested positive for Dioxin blood serum levels of around 30-60PPT which is high and the same levels as the Ranch Hand aircrew. After monitoring for several years both groups showed no significant health effects. No combat soldier from the Vietnam war has been found with blood serum levels above normal which is 3-6PPT. Mixing the two chemicals did not alter their molecular structure and turn them into a devils brew. I don't know if Dow NZ made 2,4D but I expect they did. Mixing is not manufacturing particularly if one of the components is made elsewhere.

Submitted by Noel Benefield on Wednesday, 5 December 2018 - 10:57am


Barron it’s a common mistake about Agent Orange been no different to commercial products.
“Commercial applicators would never have selected the n-butyl ester
formulation of 2,4-D or 2,4,5-T for weed or brush control because of the
problems associated with volatility and drift. Commercial formulations
would have contained low volatile esters or water soluble amine salts and
would have contained emulsifiers, diluents,and/or surfactants.
For spray operations of commercial herbicides, applicators would have diluted the
formulations with water or diesel fuel prior to application.”…

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