A study conducted by the Public Services Regulatory Authority (ARESEP) found high levels of a fuel additive, Methylcyclopentadienyl manganese tricarbonyl, or MMT, in gasoline at storage tanks at the National Oil Refinery (RECOPE).
MTT is considered by many experts to be a neurotoxin that is commonly used to increase a fuel’s octane rating.
Shipments of gasoline with the additive entered the country on Dec. 15, 2011, according to RECOPE records.
ARESEP research found that “Super” and “Plus” gasoline have up to 93 mg of MMT per liter, while international standards recommend suppliers to use a maximum of 18 mg per liter.
The regulatory authority also said the component change was not reported by RECOPE, which is an infringement of two ARESEP decrees. RECOPE responded that Costa Rica has no regulations in place on MMT, so they are not required to report the change. They also said they never asked for MMT to be added to the fuel.
Studies found that MTT damages a vehicle’s exhaust system and increases fuel consumption. Studies also show that MMT exposure could lead to respiratory problems and neurological damage.
Although banned as a gasoline additive in the United States from 1977 to 1995, MMT is still used in the U.S. and Canada since 1976.