The Supreme Court could be close to ruling on Australia’s biggest ever food safety payout.

A settlement is being finalised that could see hundreds of people allegedly poisoned by toxic Bonsoy soy milk share in $25 million.

Australian distributor and brand owner, Spiral Foods, and Japanese companies Muso and Marusan Ai-Co have agreed to the settlement without admitting liability.

The case arose after claims from about 500 people that they suffered health problems caused by dangerously high iodine levels contained in Bonsoy between 2004 and 2009.

The Court has since heard that Bonsoy was reformulated in August 2003 to replace pure kombu (seaweed) with kombu powder, which may have increased the level of iodine.

It was alleged that one glass of Bonsoy contained 50 times the recommended daily intake of iodine.

Maurice Blackburn lawyer Jacob Varghese told reporters this week that the effects could be severe.

“Ranging from lethargy and anxiety from one end of the scale, to very severe episodes that would involve hospitalisation,” he said.

“In some cases people have had to have their thyroids removed.

“In a couple of cases women say that they had miscarriages as a result of the excessive iodine.

“We understand it'll be the biggest settlement of any food safety class action in Australia.

“That's quite important I think, in sending a message to food producers that the class action system is available to consumers to assert their rights if something does go wrong in the production process,” he said.

The settlement was lodged in the Supreme Court on Monday for approval, with victims expected to begin receiving payouts within six months.