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                                                                   Exhibit 99.1

For information, contact:                                          NEWS RELEASE
Media - Anne M. Knisely (713) 309-2643
Investors - Douglas J. Pike (713) 309-7141

           Equistar Agrees to Supply Propylene to Sunoco for 15 Years

             and Sell Bayport Polypropylene Unit in Pasadena, Texas

     HOUSTON, March 27, 2003 - Lyondell Chemical Company (NYSE: LYO) today
announced that its joint venture Equistar Chemicals, LP, is entering into a
long-term propylene supply arrangement with Sunoco, Inc. and is selling its
Bayport polypropylene manufacturing unit in Pasadena, Texas, to Sunoco, subject
to certain conditions. The transaction will be effective as of March 31.

     Beginning April 1, 2003, Equistar will supply propylene to Sunoco for a
period of 15 years, and a majority of the propylene to be supplied will be
provided under a cost-based formula.

     Equistar is selling its Bayport polypropylene unit to Sunoco, but will
retain ownership of its Bayport low-density polyethylene (LDPE) unit. Sunoco
will operate both units. Equistar's Novolen(R)-based polypropylene manufacturing
plant in Morris, Illinois, and its interest in the Novolen Technology Holdings
venture are not included in the transaction.

         The total consideration to Equistar for the supply arrangements and
asset sale is approximately $190 million, plus the value of the Bayport
polypropylene inventory.

      "Equistar is a major producer of propylene and Sunoco is a growing,
committed producer of polypropylene," said Dan F. Smith, Lyondell President and
CEO and Equistar CEO. "These transactions enable each company to focus on its
particular area of expertise. Additionally, the cash received from these
transactions will enable Equistar to enhance liquidity, which remains key among
our financial priorities."

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      Lyondell Chemical Company, (www.lyondell.com), headquartered in Houston,
Texas, is a leading producer of: propylene oxide (PO); PO derivatives, including
propylene glycol (PG), butanediol (BDO) and propylene glycol ether (PGE);
toluene diisocyanate (TDI); and styrene monomer and MTBE as co-products of PO
production. Through its 70.5% interest in Equistar Chemicals, LP, Lyondell also
is one of the largest producers of ethylene, propylene and polyethylene in North
America and a leading producer of ethylene oxide, ethylene glycol, high
value-added specialty polymers and polymeric powder. Through its 58.75% interest
in LYONDELL-CITGO Refining LP, Lyondell is one of the largest refiners in the
United States, principally processing extra heavy Venezuelan crude oil to
produce gasoline, low sulfur diesel and jet fuel.

      The statements in this release relating to matters that are not historical
facts are forward-looking statements that are subject to risks and
uncertainties. Actual results could differ materially, based on factors
including, but not limited to: the cyclical nature of the chemical and refining
industries; availability, cost and volatility of raw materials and utilities;
governmental regulatory actions and political unrest; global economic
conditions; industry production capacity and operating rates; the supply/demand
balance for Lyondell's and its joint ventures' products; competitive products
and pricing pressures; access to capital markets; technological developments and
other risk factors. For more detailed information about the factors that could
cause actual results to differ materially, please refer to Lyondell's Annual
Report on Form 10-K for the year ended December 31, 2002, which was filed in
March 2003.