Mexico tortilla maker Gruma derivatives losses rise

MEXICO CITY Feb 23 (Reuters) - Mexican tortilla maker Gruma's losses on foreign exchange derivatives grew to 11.2 billion pesos ($811 million) in December after the global credit debacle drove the country's peso to record lows.

Supermarket operator Comercial Mexicana (COMEUBC.MX) defaulted on payments to creditors in October and other companies have revealed steep losses in currency derivatives as the peso MEX01MXN= fell into a tailspin.

Gruma (GRUMAB.MX) said in a stock market filing on Monday that almost all the mark-to-market declines in its derivatives positions were from losing bets against the dollar.

The tortilla maker revealed losses of more than $700 million in the value of its foreign exchange bets in October, leading Fitch and Standard & Poor's to downgrade its credit ratings.

Underscoring the complexity of the derivatives that some companies in Mexico have become caught up in, industrial firm Grupo Industrial Saltillo GISSA.MX has hired outside help to analyze the cost of its positions as counterparties demand it pay $149 million in losses.

Paper maker Corporacion Durango CODUSA.MX and cement giant Cemex (CMXCPO.MX) (CX.N) were also caught offguard with losing derivatives bets.

Mexican authorities are investigating whether companies investing heavily in derivatives broke rules by not revealing their positions to investors.

Aiming to reassure investors, regulators have also required publicly listed companies begin making detailed reports of their derivatives positions. ($1 = 13.815 pesos at end-December) (Reporting by Noel Randewich; Editing by Bernard Orr)