EXHIBIT 99.1



                           LYONDELL CHEMICAL COMPANY

                                   LETTER TO
                   THE DEPOSITORY TRUST COMPANY PARTICIPANTS

                                      FOR

                           TENDER OF ALL OUTSTANDING


                         9-5/8% SENIOR SECURED NOTES,
                             SERIES A, DUE 2007 IN
                            EXCHANGE FOR REGISTERED
                         9-5/8% SENIOR SECURED NOTES,
                              SERIES A, DUE 2007

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THE EXCHANGE OFFER WILL EXPIRE AT 5:00 P.M., NEW YORK CITY TIME, ON
____________, 1999, UNLESS EXTENDED (THE "EXPIRATION DATE"). OUTSTANDING NOTES
TENDERED IN THE EXCHANGE OFFER MAY BE WITHDRAWN AT ANY TIME PRIOR TO 5:00 P.M.,
NEW YORK CITY TIME, ON THE EXPIRATION DATE FOR THE EXCHANGE OFFER.
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To Depository Trust Company Participants:

     We are enclosing herewith the materials listed below relating to the offer
by Lyondell Chemical Company (the "Issuer"), Lyondell Chemical Worldwide, Inc.
and Lyondell Chemical Nederland, Ltd. (together, the "Subsidiary Guarantors") to
exchange (the "Exchange Offer") 9-5/8% Senior Secured Notes, Series A, Due 2007
(the "New Notes"), the issuance of which has been registered under the
Securities Act of 1933, as amended (the "Securities Act"), for a like principal
amount of the issued and outstanding unregistered 9-5/8% Senior Secured Notes,
Series A, Due 2007 (the "Outstanding Notes"), upon the terms and subject to the
conditions set forth in the prospectus dated _______________, 1999 (the
"Prospectus") and the related Letter of Transmittal.

     We are enclosing copies of the following documents:

          1. Prospectus dated ____________, 1999

          2. Letter of Transmittal (together with accompanying Substitute Form
             W-9 Guidelines)

          3. Notice of Guaranteed Delivery

          4. Letter of instructions that may be sent to your clients for whose
             account you hold Outstanding Notes in your name or in the name of
             your nominee, with space provided for obtaining such client's
             instructions with regard to the Exchange Offer.

     We urge you to contact your clients promptly.  Please note that the
Exchange Offer will expire at 5:00 p.m., New York City time, on ____________,
1999, unless extended.

     The Exchange Offer is not conditioned upon any minimum aggregate principal
amount of Outstanding Notes being tendered for exchange or upon the consummation
of any other Exchange Offer.

     Pursuant to the Letter of Transmittal, each holder of Outstanding Notes
will represent to the Issuer that (i) any New Notes received are being acquired
in the ordinary course of business of the person receiving such New Notes, (ii)


such person does not have an arrangement or understanding with any person to
participate in the distribution of the Outstanding Notes or the New Notes within
the meaning of the Securities Act and (iii) such person is not an "affiliate,"
as defined in Rule 405 under the Securities Act, of the Issuer or any Subsidiary
Guarantor or, if it is such an affiliate, it will comply with the registration
and prospectus delivery requirements of the Securities Act to the extent
applicable. In addition, each holder of Outstanding Notes will represent to the
Issuer that (i) if such person is not a broker-dealer, it is not engaged in, and
does not intend to engage in, a distribution of New Notes and (ii) if such
person is a broker-dealer that will receive New Notes for its own account in
exchange for Outstanding Notes that were acquired as a result of market-making
activities or other trading activities, it will deliver a Prospectus in
connection with any resale of such New Notes; however, by so acknowledging and
by delivering a Prospectus, it will not be deemed to admit that it is an
"underwriter" within the meaning of the Securities Act.

     The enclosed letter to clients contains an authorization by the beneficial
owners of the Outstanding Notes for you to make the foregoing representations.

     The Issuer will not pay any fee or commission to any broker or dealer or to
any other person (other than the Exchange Agent) in connection with the
solicitation of tenders of Outstanding Notes pursuant to the Exchange Offer. The
Issuer will pay or cause to be paid any transfer taxes payable on the transfer
of Outstanding Notes to it, except as otherwise provided in Instruction 7 of the
enclosed Letter of Transmittal.

     Additional copies of the enclosed material may be obtained from us.

                                    Very truly yours,

                                    The Bank of New York


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