An opponent of New Zealand's tuberculosis (TB) eradication programme has successfully challenged the agency which spends millions in public funds poisoning possums which it blames for the spread of the disease.

A ruling issued yesterday by the Advertising Standards Authority Appeal Board upheld a claim by Wairarapa environmentalist Bill Benfield that an email sent to farmers throughout the country by the TB agency Ospri claiming that possums were responsible for around half of all new infections in cattle and deer herds "was not supported by the evidence".

The board said Ospri had not produced evidence to back its statement, and ruled the advertisement was in breach of elements of the advertising code of ethics. The decision overturned an earlier ruling by the ASA Complaints Board, which dismissed Benfield's complaint.

But Benfield then submitted further information about the incidence of TB in possums, including answers given in Parliament made by the Ministry of Primary Industries, Nathan Guy.


Benfield told the appeal hearing that Ospri's ad was "false and misleading" regarding the role of possums spreading bovine TB.

In his complaint, he argued that Ospri was exaggerating the incidence of the disease among possums.

He said material provided by ministerial responses to questions in Parliament showed that TB in Southland, Waikato and the West Coast was so low they could be declared free of the disease.

In its response, Ospri said data collected by its vets backed its view regarding sources of infection.

"It is neither necessary not practical to obtain unequivocal scientific proof of the cause of infection in each and every case," Ospri told the appeal, adding that the disputed statement - that possums were to blame for around half of all new TB infections - was "not false or misleading."

It stated that so long as TB continued to be detected in livestock then control measures would continue, as it was required to under the statutory national TB plan.

Ospri is a private company set up as a charity. It is funded through a slaughter levy on dairy, beef and deer farmers, along with a significant injection of taxpayer funds.

Earlier this year Guy announced the Government would invest $69.8m over the next four years for TB eradication, on top of $30.2m already contributed. Ospri has a goal of ridding NZ livestock of TB in 10 years, and possums - a carrier of the disease - by 2040.

Much of Ospri's work targeting possums involves the use of the pesticide 1080, which Benfield strongly opposes.

The appeal board found the Ospri ad breached the principle that advertisements should not be misleading or deceptive, and another principle that material should be prepared with a sense of social responsibility. The ruling also found the advertisement in breach of a code of ethics rule concerning "truthful presentation."

Ospri said it would respond on Friday to the ruling.