BEIJING - More than 200 families whose babies fell ill after drinking tainted infant formula said Monday they are taking their case to China's highest court after being repeatedly ignored by lower courts.

The lawsuit involving 213 families poses a challenge to the government's attempts to end one of the country's worst food safety crises.

The scandal over milk spiked with an industrial chemical has been blamed for the deaths of six babies and the sickening of nearly 300,000 others with kidney stones and kidney failure.

The 22 Chinese dairies involved have proposed a $160 million US compensation plan, but many parents want higher compensation and long-term treatment for their babies.

"The reason why I'm bringing this case to court is not about money but about my child's future," said Zhang Ge, a single mother in Beijing who quit her job at an Internet advertising company to look after her sick son.

Beijing lawyer Xu Zhiyong said lawyers for the families mailed an application Friday to the Supreme People's Court in Beijing to sue the dairies.

But it seemed unlikely the court would hear the lawsuit, given that lower courts have so far refused to hear at least a dozen lawsuits in the politically sensitive scandal.

The lawyers' group has not been notified if the application has been received. Phone calls to the inquiry office of the Supreme People's Court rang unanswered Monday.

The government and the dairy companies had hoped the countrywide payout scheme would ease public anger. Instead, it has given embittered, outspoken parents across the country a common cause.

Xu said the lawsuit seeks $5.3 million in total compensation for the families.