Exhibit 23
CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
We hereby consent to the incorporation by reference in the Registration Statement on Form S-8 (No. 333-125087) of Lyondell Chemical Company of our report dated June 29, 2005 relating to the financial statements of the Equistar Chemicals, LP Savings and Investment Plan for Hourly Represented Employees, which appears in this Form 11-K.
/s/ PricewaterhouseCoopers LLP
PricewaterhouseCoopers LLP
Houston, Texas
June 29, 2005
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