Bonsoy soy milk has agreed to compensate nearly 500 victims $25m, in the biggest payout for a food safety case in Australian legal history.

The case, which began in 2010, alleged that unsafe levels of iodine were added to the ingredients of the soy milk product via a seaweed product called Kombu, with nearly 500 people claiming they suffered dramatic and damaging health consequences as a result.

Jacob Varghese, class action Principal at Australia’s leading class action law firm Maurice Blackburn, said the thyroid and other health problems suffered by those that consumed Bonsoy were severe, and in some cases, life altering.

"We began this case in 2010, and it reinforces just how tough it is to pull these class actions together, to run them and fight them this hard for this long, and ultimately, how difficult it is to achieve a resolution for victims, hundreds of victims in this case," Varghese said.

"We believe this is the highest settlement of a food safety class action in Australia’s history, and it reinforces how important it is for people to have access to a mechanism that can help remedy a mass wrong, and in the process, place a check on corporate conduct.

"There are nearly 500 people we’re representing in this class action, and all of them have been badly affected in a variety of ways. For some like Erin Downie, our lead plaintiff, the effects still linger."

Downie became ill shortly after giving birth to her daughter Mirakye in 2008. She started drinking more Bonsoy in the belief its health benefits would help with breastfeeding. She was rushed to hospital by ambulance, suffered heart palpitations and unconsciousness.

She lost muscle function, became bedridden and her family suffered financial hardship due to her inability to work and her need for a carer.

"I lost the first years of being able to enjoy my only child’s life because of the illnesses I suffered. Instead of hundreds of precious family memories, my memories are of being severely sick," Downie said.

Under the settlement, the defendant companies will pay $25 million into a fund to be distributed to participants in the class action.

The settlement must be approved by the Supreme Court of Victoria. A hearing on approval of the settlement will occur on 29 January 2015. The defendants have not admitted liability.