Fuel testing agency Lintec Testing Services has warned that three fuel oil samples taken recently from vessels that have bunkered in Riga, Latvia, have shown the presence of Dicyclopentadiene (DCPD), a synthetic substance not naturally occurring within marine fuel. Lintec Managing Director Geoff Jones said, “The presence of DCPD was detected by Lintec’s chemical screening service. This fuel is clearly in breach of Section 5.1 of the ISO-8217 specification, which clearly states that ‘the fuels should be homogeneous blends of hydrocarbons derived from petroleum refining. This shall not preclude the incorporation of small amounts of additives intended to improve some aspects of performance. The fuels shall be free from inorganic acids and from used lubricating oils.