The Vegetable and Potato Growers Federation (Vegfed) yesterday denied reports that it kept information secret on the safety of zucchinis.
In January, a naturally occurring toxin, cucurbitacin, produced by zucchini plants to deter pests, reached dangerous levels in some plants due to unusual weather.
Cucurbitacin poisoning symptoms can include nausea, stomach cramps,
diarrhoea and vomiting.
Chief executive Peter Silcock said the issue was not brought to Vegfed's notice until last month, "well after the events had occurred".
"As soon as we became [aware] of the problem we immediately began working with the Ministry of Health and Crown Public Health, Christchurch.
"We all agreed that issuing the information to the public would be alarmist and like warning people about a storm a week after it had passed," he said.
Eleven people became ill from eating the vegetables in Christchurch and five in Auckland, although Auckland food safety investigation officer Adam Simpson said it was likely others had been affected but had not reported it.
Complaints had also been received in Whakatane and Northland.
Affected zucchinis, also known as courgettes, give off a pungent smell that has been described as similar to cat urine, and they have a bitter taste.
A letter leaked to the Dominion newspaper showed Vegfed did not want the media to know about the toxin. The federation chose not to publicise advice from a scientist that eating affected zucchinis could cause "long-lasting harm".
The letter, from federation executive officer Ron Gall, said it was important to keep the problem under wraps.
But Ian Shaw, the food safety scientist called in to look into the problem, said yesterday that Vegfed should have told consumers sooner.
Mr Silcock said Vegfed was "confident that growers will recognise the problem and ensure the product is not offered for sale in the future".
Crown Public Health Christchurch health protection officer Debbie Smith said the first case was reported last March.
A Christchurch couple had used zucchinis in a stirfry and had come down with diarrhoea and stomach cramps.
Nine more Christchurch people were affected in January.
The ministry will release an information sheet on the types of fruits and vegetables with natural toxins within eight weeks.
Other vegetables that may contain natural toxins are taro, rhubarb, green potatoes, kumara and red kidney beans.
- NZPA
