7.55% Uses in Miscellaneous Clause

Miscellaneous from Credit Agreement

AMENDMENT (this Amendment) dated as of September 29, 2006 to the Credit Agreement dated as of August 16, 2006 (as amended, the Credit Agreement) among LYONDELL CHEMICAL COMPANY, a Delaware corporation, and the AGENTS and LENDERS from time to time party thereto.

Miscellaneous. The definition of Lyondell-Equistar Debt is amended to read in its entirety as follows: Lyondell-Equistar Debt means Debt under the 7.55% Notes Due 2026 issued by the Borrower pursuant to an Indenture dated as of January 29, 1996 between the Borrower and Texas Commerce Bank National Association, as trustee, as supplemented by the First Supplemental Indenture dated as of February 15, 1996 and the Second Supplemental Indenture dated as of December 1, 1997, which Debt has been assumed by Equistar and with respect to which, as between the Borrower and Equistar, Equistar is the obligor and the Borrower is the guarantor.