Diagnoses of herbicide poisoning rejected

- 1 February 1987

Claims by an Auckland Physician, Dr Matthew Tizard, of having diagnosed cases of herbicide Poisoning have been rejected by a task force set up by the Director-General of Health.

In a report released yesterday on its investigations into the E.A V. technique (electro-acupuncture according to Voll) used by Dr Tizard, the task force said it was unable to find any scientific evidence to support the validity and reliability of the method of diagnosis.

Although Dr Tizard gave a “practical demonstration” of the technique, the task force expressed concern that he had declined to participate in a controlled trial.

Dr Tizard, of Remuera, sent submissions in September, 1885, to an Environmental Council working party on 2,4,5—T, with a letter outlining theoretical aspects of electro-acupuncture diagnosis.

He claimed to have diagnosed cases of herbicide poisoning.

Two months later, he notified the Health Department of chronic poisonings by the herbicides 2.4,5—T, paraquat, and asulam, and the insecticide maldison (malathion), after having expressed his disappointment that the department had not followed up his initial surveys.

The Director-General of Health, br Ron Baker, set up the task force late in November to investigate Dr Tizard’s claims.

“The E.A.V. technique was found to be subject to a high potential for operator bias, and no scientifically acceptable supporting literature for the technique could be found,” the task force said.

In 195 cases of pesticide poisoning notified by Dr Tizard, no consistent diagnostic pattern of symptoms could be discerned, and no syndromes of chronic 2,4,5—T or paraquat poisoning were recognised in the medical literature.

In 82 per cent of cases there was no evidence of exposure to the pesticides in question.

“To support his method of diagnosis, Dr Tizard supplied the task force with the results of analyses for herbicides of blood samples from eight individuals,” the report said.

“The task force considered these results to be inadequate and of no scientific value.”

It declined to comment on the validity of treatment, but recommended that the Director-General begin studies to determine residue levels of phenoxy herbicides, paraquat, and other relevant pesticides in foodstuffs and water in New Zealand; and that studies be made to determine body-burdens of hes in blood or other tissue levels of New Zealanders.

The task force said that if Dr Tizard’s techniques were valid, he had nothing to fear in participating in a controlled trial. But in the absence of the trial “the existing controversy would continue.”

“The task force does not recommend the recognition of the therapeutic procedures until both the diagnostic and therapeutic procedures specified by Dr Tizard have been properly validated,” the report said.