All members of the board of Japanese company Duskin have tended letters of resignation over the use of a banned additive in food sold at Mister Donuts, a subsidiary, the firm said on Thursday, reports the Daily Yomiuri.
A Duskin spokesman said president Takeshi Ueda would decide whether to accept the resignations of the 24 board members after studying proposals to avoid a repeat of the incident and to regain consumer confidence.
It was discovered in May that Mister Donuts had sold Chinese meat dumplings containing t-butylohydroquinone (TBHQ), an antioxidant banned in Japan, from the autumn of 2000.
Excessive consumption of the additive is thought to cause health problems, including weight loss.