HOUSTON, April 21, 2005 /PRNewswire-FirstCall via COMTEX/ -- Morris Gelb, Executive Vice President and Chief Operating Officer of Lyondell Chemical Company (NYSE: LYO), will address analysts at the following event:

Analyst               Banc of America Securities 2005 Basic Industries
     Conference:           Conference in New York, Wednesday, May 4, 2005, at
                           9:45 a.m. Eastern Time.

     Web Site Access:      Live audio-only webcasting will be provided in
                           RealPlayer(TM) and Windows Media formats.
                           Beginning at 9:45 a.m. Eastern Time on the day of
                           the event, the webcast can be accessed at
                           http://www.lyondell.com/investorpresentations .

                           The replay webcast will be available by 2:30 p.m.
                           Eastern Time on May 4, 2005 at
                           http://www.lyondell.com/investorpresentations .
                           The replay will be available until May 20, 2005.

     Presentation:         The slides will be available at the time of the
                           presentation and afterwards at
                           http://www.lyondell.com/investorpresentations .

     Related Disclosures:  Reconciliations of non-GAAP financial measures to
                           GAAP financial measures and any other applicable
                           disclosures (including the slides) will be
                           available at the time of the presentations and
                           afterwards at
                           http://www.lyondell.com/investorpresentations .

    ABOUT LYONDELL

Lyondell Chemical Company, headquartered in Houston, Texas, is North America's third-largest independent, publicly traded chemical company. Lyondell is a major global manufacturer of basic chemicals and derivatives including ethylene, propylene, titanium dioxide, styrene, polyethylene, propylene oxide and acetyls. It also is a significant producer of gasoline blending components. The company has a 58.75 percent interest in LYONDELL- CITGO Refining LP, a refiner of heavy, high-sulfur crude oil. As a result of Lyondell's November 30, 2004 acquisition of Millennium Chemicals Inc., Millennium and Equistar Chemicals, LP are wholly owned subsidiaries of Lyondell. Lyondell is a global company operating on five continents and employs approximately 10,000 people worldwide.

SOURCE: Lyondell Chemical Company

media, Susan P. Moore, +1-713-309-4645, or investors, Douglas J. Pike, +1-713-309-4590, both of Lyondell Chemical Company