A FUEL supplier based in West Thurrock says it has identified unusually high levels of silicon in four petrol storage tanks.

Harvest Energy issued a statement saying it had "now isolated the higher silicon fuel and can guarantee that no further supplies of high silicon unleaded petrol will be distributed from the West Thurrock terminal".

Silicon is not usually present in unleaded fuel and the company had not tested for it in the past.

The company said it would ensure silicon tests are carried out in the future.

The statement added: "All petrol at the terminal currently available for distribution has minimal (less than one part per million) silicon levels in line with usual industry norms."

Two supermarkets - Tesco and Morrison's have taken action to ensure the infected petrol is not sold.

Hundreds of motorists have been reporting severe problems with their cars, claiming the faulty petrol was to blame.

The statement from Harvest Fuels in full: "Harvest Energy has this morning announced that it has completed its initial investigation of possible fuel contamination of the product stored at the oil terminal owned by Vopak at West Thurrock, Essex. The company, which has been trading in the UK since 1995, shares the terminal's facilities with Greenergy, another independent blender and wholesaler of fuels.

The testing has identified unusually high levels of silicon in four petrol storage tanks at the terminal. Fuel blended from these tanks has been supplied to various petrol retailers who take fuel from the West Thurrock terminal.

Harvest Energy's testing confirms that its petrol reaches the European and British specification BS EN 228 for unleaded fuel. However, the specification does not include a test for silicon, as it is not an element that would normally be expected to be present within finished grade petrol or blend components, and for this reason its presence was not detected prior to sale. We will now be testing for silicon as a matter of course. In addition Harvest Energy will propose to the relevant European and British Standards organisations, via its trade body the Association of UK Oil Independents (AUKOI), the inclusion of a silicon test within the BS EN 228 standard for unleaded petrol.

The company is also keen to work with the Society of Motor Manufacturers and Traders (SMMT) to help identify the presence of other elements that may not currently be included in the BS EN 228 specification and which the SMMT believes may have an adverse impact on vehicle performance.

Harvest Energy has now isolated the higher silicon fuel and can guarantee that no further supplies of high silicon unleaded petrol will be distributed from the West Thurrock terminal. All petrol at the terminal currently available for distribution has minimal (less than one part per million) silicon levels in line with usual industry norms.

Harvest Energy is working with its customers who retail petrol to British motorists to allow them to ensure that all future product sold is of the usual expected standard. As part of this process, the company has appointed an independent inspection company to test fuel stocks at over 100 petrol stations across the South East over the weekend.

Harvest Energy Managing Director Franco Bussandri said "We are very sympathetic to the plight of motorists who have been affected by this problem with unleaded petrol. We are working as closely as we can with our customers the retailers, to address such motorists concerns. We would ask motorists who feel they may have been affected to contact their fuel retailer for advice."