You are using an outdated browser For a better experience using this site, please upgrade to a modern web browser. Subscribe Get Daily Email Subscribe --> Contact Us Sign in Home News & Features Compliance Costs Bunker Prices Bunker Intelligence Asia/Pacific News Latest Features World Americas EMEA Asia/Pacific Home News & Features Asia / Pacific FOBAS Bulletin: Estonian Shale Oil and Stability Issues - Singapore FOBAS Bulletin: Estonian Shale Oil and Stability Issues - Singapore by FOBAS Friday May 8, 2026 Tweet Follow @shipandbunker In recent weeks,  FOBAS has tested a number of fuels from Singapore that under detailed chemical analysis with GCMS methods, showed a chemical fingerprint consistent with Estonian Shale Oil. Shale oil and particularly Estonian shale oil is seen from time to time in fuel blends in certain ports, particularly in Singapore and ARA region. In some of these recent fuels, the estimated concentrations are high, potentially up to 25% of the blend. The routine analysis results of these fuels appear on-spec compared to ISO8217 RMG380 grade fuels including Total Sediment results not particularly high. The vessels using these fuels recently tested with confirmed Shale oil are reporting certain operational issues, including excessive sludging throughout the fuel system, blocking of filters and in one case fuel pump issues. As detailed chemical analysis is not carried out routinely on all fuels, it is difficult to say how many fuels may also have Shale oil in the blend. However, from looking at other fuels properties and other supplies from the same barges and suppliers, we can estimate many other vessels have bunkered fuels with varying levels of Shale oil. Not all these ships have yet given operational feedback. In general, Shale oil is often seen as mentioned in certain ports and in many cases, fuels used without problem. However, there is also a long history of fuel stability and sludge-related problems related to Estonian Shale oil