James Hardie lost its appeal against an Australian Taxation Office assessment yesterday and could be forced to pay back-taxes of $357.36 million plus interest and costs, barring a successful appeal.

Compensation lawyers Maurice Blackburn say the ruling is a blow to the company's bottom line that could have consequences for mesothelioma victims.

Maurice Blackburn principal Andrew Dimsey said that the ongoing uncertainty about James Hardie's financial position ''raised concerns for the future victims of asbestos-related disease''.

Under an agreement with the NSW Government, James Hardie pays 35 per cent of its annual cash flow to the Asbestos Injuries Compensation Fund which compensates sufferers of asbestos-related diseases.

But the company's disappointing first-quarter result and poor outlook have raised fears the AICF could run out of funds.

James Hardie said this month the stalled US housing recovery would affect its bottom line in the current financial year.

''The long-term security of funding for asbestos-related claims is dependent on the recovery of the US housing market, which is unfair to the blameless victims of James Hardies' misconduct,'' Mr Dimsey said.