"Falling angels" could hit $260 billion of emerging market debt
* Russia loses investment grade credit rating from S&P
* Others may follow, factors include oil prices, instability
* Almost $260 billion in bonds risk being relegated to junk
* Brazil, Turkey, South Africa, Indonesia also at risk -bank
By Sujata Rao
LONDON, Jan 29 (Reuters) - After a golden decade of improvement, credit ratings for a swathe of developing economies risk falling back to "junk", with huge potential costs for up to a tenth of outstanding emerging market bonds.
Many mainstream investment and pension funds have rules preventing them from holding debt unless it is classified as investment grade by at least two of the big ratings agencies, and a number of countries are at risk due to problems ranging from tumbling commodity export prices to political instability.
Russia this week became the first of the major economies to lose its investment grade status from Standard & Poor's, falling out off the top ratings category for credits deemed to have a low risk of default for the first time in a decade.
If Moody's and Fitch follow, conservative investors barred from owning junk securities must sell their holdings. JPMorgan estimates this means they may ditch $6 billion in Russian government rouble and dollar debt. Continuación...