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                                                                    Exhibit 99.1

For information, contact:
Media - Kelly McCarthy (713) 652-4518
Investors - Doug Pike (713) 652-7141

                                                           FOR IMMEDIATE RELEASE



     Lyondell Shareholders Approve Issuance of New Series B Common Shares.
             Lyondell to Acquire Occidental's Interest in Equistar.


Highlights

     o    New Shares and other securities will be sold to Occidental Petroleum

     o    Lyondell's interest in Equistar to increase to 70.5% with acquisition
          of Occidental's share

     o    Occidental's Ray Irani and Stephen Chazen to join Lyondell Board of
          Directors

     HOUSTON, August 21, 2002 - At a special meeting today, shareholders of
Lyondell Chemical Company (NYSE:LYO) approved the creation of a new Series B
common stock and the sale of the new shares and other securities to a subsidiary
of Occidental Petroleum Corporation. Shareholders also approved an increase in
Lyondell's authorized common stock from 250 million shares to 420 million
shares.

     As previously announced, Lyondell will use the cash proceeds from the sale
of the securities to Occidental to purchase Occidental's 29.5% interest in
Equistar Chemicals, LP, bringing Lyondell's interest in Equistar to 70.5%.
Millennium Chemicals Inc. continues to own the remaining 29.5% interest in
Equistar. Lyondell's sale of securities and purchase of Occidental's interest in
Equistar will close simultaneously and are expected to occur as early as
tomorrow.

     "We are pleased that the shareholders approved these transactions, which
will enable us to complete the acquisition of Occidental's interest in
Equistar," said Dan F. Smith, Lyondell's President and Chief Executive Officer.
"This is advantageous to Lyondell's shareholders and bondholders because this
will significantly increase our proportionate share of Equistar's earnings and
cash flow as the chemical cycle improves over the next few years. This will

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accelerate our debt repayment capability and enable us to more rapidly improve
Lyondell's balance sheet."

     Occidental will receive the following for its investment in Lyondell:

     o    34 million shares of the newly issued Series B Common Stock. These
          shares have the same rights as Lyondell's regular common stock with
          the exception of the dividend. The Series B common stock will pay a
          dividend at the same rate as the regular common stock but, at
          Lyondell's option, the dividend may be paid in additional shares of
          Series B (Payment in Kind) or in cash. The issuance of the new Series
          B shares also provides that Occidental may convert the shares to
          regular common stock three years after issuance or earlier in certain
          circumstances.

     o    Five-year warrants to acquire five million shares of Lyondell regular
          common stock at $25 per share.

     o    A contingent payment equivalent in value to 7.38 percent of Equistar's
          cash distributions for 2002 and 2003 up to a total of $35 million,
          payable in cash or Lyondell common stock, as determined by Lyondell.

     As part of the transaction, two Occidental executives, Dr. Ray R. Irani,
Chairman and Chief Executive Officer, and Stephen I. Chazen, Chief Financial
Officer and Executive Vice President, will be appointed members of the Lyondell
Board of Directors upon the closing of the transactions. Occidental will own
approximately 21.3% of Lyondell's issued and outstanding common stock.

     Equistar Chemicals, LP was formed in December 1997 with the combination of
the olefins and polymers businesses of Lyondell and Millennium. Occidental
joined the partnership in May 1998 with the contribution of the ethylene,
propylene, and ethylene oxide and derivatives businesses of Occidental Chemical
Corporation, a subsidiary of Occidental Petroleum.

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Lyondell Chemical Company, (www.lyondell.com), headquartered in Houston, Texas,
is the world's largest producer of propylene oxide (PO); the world's number
three supplier of TDI (toluene diisocyanate); a leading producer of propylene
glycol; a leading producer of other PO derivatives such as BDO (butanediol) and
PGE (propylene glycol ether); and a producer of styrene monomer and MTBE as
co-products of PO production. Through its 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 polypropylene, ethylene
oxide, ethylene glycol, high value-added specialty polymers and polymeric
powder. Through its 58.75% interest in LYONDELL-CITGO Refining LP,

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Lyondell is one of the largest refiners in the United States, 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, future global economic conditions, further increases in raw material
and/or energy costs, access to capital markets, industry production capacity and
operating rates, the supply/demand balance for Lyondell's and its joint
ventures' products, competitive products and pricing pressures, technological
developments, changes in governmental regulations 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, 2001, filed with the Securities and Exchange Commission
in March 2002, Lyondell's Quarterly Report on Form 10-Q for the quarter ended
June 30, 2002, which was filed in August 2002, and the proxy statement that
Lyondell filed with the Securities and Exchange Commission in July 2002 with
respect to its Special Meeting of Shareholders relating to the transactions with
Occidental.