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                                                                    Exhibit 4.10

                           LYONDELL CHEMICAL COMPANY

                2000 NONQUALIFIED STOCK OPTION AWARD AGREEMENT
                          FOR NON-EMPLOYEE DIRECTORS

          Lyondell Chemical Company (the "Company") hereby grants on February 3,
2000 the "Grant Date") to [PARTICIPANT] (the "Optionee"), a non-employee
director of the Company, a right (the "Option") to purchase from the Company up
to but not exceeding in the aggregate 5,000 shares of Common Stock, par value
$1.00 per share ("Option Shares"), of the Company ("Common Stock") at $12.9125
per share (the "Exercise Price"), such number of shares and such price per share
being subject to adjustment as provided in Section 8 hereof, and further subject
to the following terms and conditions:

          1.  ADMINISTRATION.  The Directors Benefit Committee (the "Committee")
shall have all necessary authority and discretion to interpret any provision of
this Option or to determine any question regarding grant of options hereunder.
Any determination or interpretations of the Committee shall be final, conclusive
and binding on all persons.

          2.  EXERCISE SCHEDULE.

          (a) This Option shall become exercisable in three cumulative
     installments, with one-third of the Option Shares becoming exercisable on
     February 3, 2001, an additional one-third of the Option Shares becoming
     exercisable on February 3, 2002, and  the final one-third of the Option
     Shares becoming exercisable on February 3, 2003.

          (b) This Option shall become fully exercisable, irrespective of the
     limitations set forth in subparagraph (a) above, upon termination of his or
     her service as a non-employee director of the Company due to death,
     Disability or Retirement, or upon a Change in Control.

          (c) This Option shall become fully exercisable, irrespective of the
     limitations set forth in subparagraph (a) above, if, at any time prior to
     February 3, 2003, the Fair Market Value per share of Common Stock is
     greater than or equal to two times the Exercise Price for at least 5
     consecutive trading days.

          (d) For purposes of this Agreement, the following definitions apply:

              (i)   "Disability" means a permanent and total disability as
          defined in Section 22(e)(3) of the Internal Revenue Code, as amended.

              (ii)  "Retirement" means ceasing to be a director of the Company
          (i) on or after age 72 or (ii) at any time prior to age 72 with the
          consent of a majority of the members of the Board of Directors other
          than the Optionee.

              (iii) "Change in Control" shall be deemed to have occurred as of
     the date that one or more of the following occurs:

               (a) Individuals who, as of the date hereof, constitute the entire
          Board

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          of Directors of the Company ("Incumbent Directors") cease for any
          reason to constitute at least a majority of the Board; provided,
          however, that any individual becoming a director subsequent to the
          date hereof whose election, or nomination for election by the
          Company's shareholders, was approved by a vote of at least a majority
          of the then Incumbent Directors shall be considered as though such
          individual was an Incumbent Director, but excluding, for this purpose
          any such individual whose initial assumption of office occurs as a
          result of either an actual or threatened election contest, as such
          terms are used in Rule 14a-11 under the Securities Exchange of 1934,
          as amended ("Exchange Act") or other actual or threatened solicitation
          of proxies or consents by or on behalf of any Person (as defined
          below) other than the Board;

               (b) The stockholders of the Company shall approve (A) any merger,
          consolidation or recapitalization of the Company (or, if the capital
          stock of the Company is affected, any subsidiary of the Company), or
          any sale, lease, or other transfer (in one transaction or a series of
          transactions contemplated or arranged by any party as a single plan)
          of all or substantially all of the assets of the Company (each of the
          foregoing being an "Acquisition Transaction") where (1) the
          shareholders of the Company immediately prior to such Acquisition
          Transaction would not immediately after such Acquisition Transaction
          beneficially own, directly or indirectly, shares or other ownership
          interests representing in the aggregate eighty percent (80%) or more
          of (a) the then outstanding common stock or other equity interests of
          the corporation or other entity surviving or resulting from such
          merger, consolidation or recapitalization or acquiring such assets of
          the Company, as the case may be (the "Surviving Entity") (or of its
          ultimate parent corporation or other entity, if any), and (b) the
          Combined Voting Power of the then outstanding Voting Securities of the
          Surviving Entity (or of its ultimate parent corporation or other
          entity, if any) or (2) the Incumbent Directors at the time of the
          initial approval of such Acquisition Transaction would not immediately
          after such Acquisition Transaction constitute a majority of the Board
          of Directors, or similar managing group, of the Surviving Entity (or
          of its ultimate parent corporation or other entity, if any), or (B)
          any plan or proposal for the liquidation or dissolution of the
          Company; or

               (c) Any Person shall be or become the beneficial owner (as
          defined in Rules 13d-3 and 13d-5 under the Exchange Act), directly or
          indirectly, of securities of the Company representing in the aggregate
          more than twenty percent (20%) of either (A) the then outstanding
          shares of common stock of the Company ("Common Shares") or (B) the
          Combined Voting Power of all then outstanding Voting Securities of the
          Company; provided, however, that notwithstanding the foregoing, a
          Change in Control shall not be deemed to have occurred for purposes of
          this Subsection (iii):

                    (1) Solely as a result of an acquisition of securities by
               the Company which, by reducing the number of Common Shares or
               other Voting Securities outstanding, increases (a) the
               proportionate number of Common Shares beneficially owned by any
               Person to more than twenty percent (20%) of the Common Shares
               then outstanding, or (b) the

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               proportionate voting power represented by the Voting Securities
               beneficially owned by any Person to more than twenty percent
               (20%) of the Combined Voting Power of all then outstanding Voting
               Securities; or

                    (2) Solely as a result of an acquisition of securities
               directly from the Company except for any conversion of a security
               that was not acquired directly from the Company,

          provided, further, that if any Person referred to in paragraph (1) or
          (2) of this Subsection (iii) shall thereafter become the beneficial
          owner of any additional Common Shares or other Voting Securities of
          the Company (other than pursuant to a stock split, stock dividend or
          similar transaction), then a Change in Control shall be deemed to have
          occurred for purposes of this Subsection (iii).

               (d) For purposes of this Section 2(d)(iii):

                   (1)  "Affiliate" shall mean, as to a specified Person,
               another Person that directly, or indirectly through one or more
               intermediaries, controls or is controlled by, or is under common
               control with, the specified Person, within the meaning of such
               terms as used in Rule 405 under the Securities Act of 1933, as
               amended ("Securities Act"), or any successor rule.

                   (2)  "Combined Voting Power" shall mean the aggregate votes
               entitled to be cast generally in the election of the Board of
               Directors, or similar managing group, of a corporation or other
               entity by holders of then outstanding Voting Securities of such
               corporation or other entity.

                   (3)  "LCR" shall mean LYONDELL-CITGO Refining Company Ltd.
               (from and after January 1, 1999, LYONDELL-CITGO Refining LP), a
               Limited Liability Company organized under the laws of the State
               of Texas.

                   (4)  "Person" shall mean any individual, entity (including,
               without limitation, any corporation, partnership, trust, joint
               venture, association or governmental body) or group (as defined
               in Sections 14(d)(3) or 15(d)(2) of the Exchange Act and the
               rules and regulations thereunder); provided, however, that Person
               shall not include the Company or LCR, any of their subsidiaries,
               any employee benefit plan of the Company or LCR or any of their
               majority-owned subsidiaries or any entity organized, appointed or
               established by the Company, LCR or such subsidiaries for or
               pursuant to the terms of any such plan.

                   (5)  "Voting Securities" shall mean all securities of a
               corporation or other entity having the right under ordinary
               circumstances to vote in an election of the Board of Directors,
               or

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               similar managing group, of such corporation or other entity.

          3.  TERMINATION OF OPTION:  The Option hereby granted shall terminate
and be of no force and effect with respect to any shares of Common Stock not
previously purchased by the Optionee upon the first to occur of:

          (a) close of business on February 2, 2010;

          (b)  with respect to

               (i)  the portion of the Option exercisable upon termination of
                    service (or which becomes exercisable upon termination due
                    to death, Disability or Retirement), the expiration of (A)
                    90 days following termination of the Optionee's service as a
                    director of the Company for reasons other than death,
                    Disability or Retirement, or (B) one year following the
                    Optionee's termination of service as a director by reason of
                    death, Disability or Retirement; and

               (ii) the portion of the Option not exercisable upon termination
                    of service for any reason other than death, Disability or
                    Retirement, the date of termination of the Optionee's
                    service as a director.

          4.  EXERCISE OF OPTION.  Subject to the limitations set forth herein,
this Option may be exercised by written notice provided to the Company as set
forth in Section 5.  Such written notice shall (a) state the number of shares of
Common Stock with respect to which the Option is being exercised and (b) be
accompanied by a check, cash or money order payable to Lyondell Chemical Company
in the full amount of the purchase price for any shares of Common Stock being
acquired or, at the option of the Optionee, accompanied by Common Stock
theretofore owned by such Optionee for at least six months that is equal in
value to the full amount of the purchase price (or any combination of cash,
check or such Common Stock).  For purposes of determining the amount, if any, of
the purchase price satisfied by payment in Common Stock, such Common Stock shall
be valued at its Fair Market Value on the date of exercise.  Any Common Stock
delivered in satisfaction of all or a portion of the purchase price shall be
appropriately endorsed for transfer and assignment to the Company.

          By acceptance of this Option, the Optionee agrees that he will not
exercise the Option granted pursuant hereto, and that the Company will not be
obligated to issue any Option Shares pursuant to this Agreement, if the exercise
of the Option or the issuance of such shares would constitute a violation by the
Optionee or by the Company of any provision of any law or regulation of any
governmental authority or any stock exchange or transaction quotation system.
Furthermore, the Optionee acknowledges that only shares of Treasury Stock may be
issued upon the exercise of this Option. Notwithstanding anything to the
contrary contained herein, this Option shall not be exercisable to the extent
the Company does not have sufficient shares of Treasury Stock and is not
permitted, under the terms of its charter documents or debt instruments, to
acquire shares of Treasury Stock to satisfy its obligations hereunder. Whether
or not the options and shares covered hereby have been registered pursuant to
the Securities Act, the Company may, at its election, require the Optionee to
give a representation in writing in form and substance satisfactory to the
Company to the effect that he is acquiring such shares for his

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own account for investment and not with a view to, or for sale in connection
with, the distribution of such shares or any part thereof.

          If any law or regulation requires the Company to take any action with
respect to the shares specified in such notice, the time for delivery thereof,
which would otherwise be as promptly as possible, shall be postponed for the
period of time necessary to take such action.

          Notwithstanding anything to the contrary contained herein, the
Company, acting through the Committee, hereby reserves the right to deliver cash
in lieu of Option Shares upon the exercise of the Option.  In such event, the
amount of cash to be paid shall be equal to the number of Option Shares that
would otherwise have been delivered multiplied by the excess of the Fair Market
Value of a share of Common Stock on the date of exercise over $12.9125.

          5.  NOTICES.  Notice of exercise of the Option must be made in the
following manner, using such forms as the Company may from time to time provide:

          (a) by registered or certified United States mail, postage prepaid, to
     Lyondell Chemical Company, Attn: Corporate Secretary, 1221 McKinney Street,
     Suite 700, Houston, Texas 77010, in which case the date of exercise shall
     be the date of mailing; or

          (b) by hand delivery or otherwise to Lyondell Chemical Company, Attn:
     Corporate Secretary, 1221 McKinney Street, Suite 700, Houston, Texas 77010,
     in which case the date of exercise shall be the date when receipt is
     acknowledged by the Company.

Notwithstanding the foregoing, (i) in the event that the address of the Company
is changed prior to the date of any exercise of this Option, notice of exercise
shall instead be made pursuant to the foregoing provisions at the Company's
current address, or (ii) in the event that the Committee delegates the
administration of option exercises to a third party administrator, notice of
exercise shall instead be made pursuant to the written instructions given to the
Optionee by the third party administrator with respect to option exercise.

          Any other notices provided for in this Agreement shall be given in
writing and shall be deemed effectively delivered or given upon receipt or, in
the case of notices delivered by the Company to the Optionee, five days after
deposit in the United States mail, postage prepaid, addressed to the Optionee at
the address specified at the end of this Agreement or at such other address as
the Optionee hereafter designates by written notice to the Company.

          6.  ASSIGNMENT OF OPTION. The Optionee's rights under this Agreement
are personal; no assignment or transfer of the Optionee's rights under and
interest in this Option may be made by the Optionee otherwise than by will or by
the laws of descent and distribution; and this Option is exercisable during his
lifetime only by the Optionee.

          Notwithstanding the foregoing, the Option is transferable by the
Optionee to (i) the children or grandchildren of the Optionee ("Immediate Family
Members"), (ii) a trust or trusts for the exclusive benefit of such Immediate
Family Members ("Immediate Family Member Trusts"), or (iii) a partnership or
partnerships in which such Immediate Family Members have at least ninety-nine
percent (99%) of the equity, profit and loss interests ("Immediate Family

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Member Partnerships"). Subsequent transfers of a transferred Option shall be
prohibited except by will or the laws of descent and distribution, unless such
transfers are made to the original Optionee or a person to whom the original
Optionee could have made a transfer in the manner described herein. No transfer
shall be effective unless and until written notice of such transfer is provided
to the Committee, in the form and manner prescribed by the Committee. Following
transfer, the Option shall continue to be subject to the same terms and
conditions as were applicable immediately prior to transfer, and, except as
otherwise provided herein, the term "Optionee" shall be deemed to refer to the
transferee. The consequences of termination of employment shall continue to be
applied with respect to the original Optionee, following which the Options shall
be exercisable by the transferee only to the extent and for the periods
specified in this Agreement.

     After the death of the Optionee, exercise of the Option shall be permitted
only by the Optionee's executor or the personal representative of the Optionee's
estate (or by his assignee, in the event of a permitted assignment) and only to
the extent that the Option was exercisable on the date of the Optionee's death.

          7.  STOCK CERTIFICATES.  Certificates representing the Common Stock
issued pursuant to the exercise of the Option will bear all legends required by
law and necessary or advisable to effectuate the provisions of this Option.

          8.  ADJUSTMENTS.   (a)  The existence of this Option shall not affect
     in any manner the right or power of the Company to make or authorize any or
     all adjustments, recapitalization, reorganizations or other changes in the
     ownership of the Company or its business or any merger or consolidation of
     the Company, or any issue of bonds, debentures, preferred or prior
     preference stock (whether or not such issue is prior to, on a parity with
     or junior to the Common Stock) or other obligations, or the dissolution or
     liquidation of the Company, or any sale or transfer of all or any part of
     its assets or business, or any other Company act or proceeding of any kind,
     whether or not of a character similar to that of the acts or proceedings
     enumerated above.

          (b) In the event of any Common Stock distribution or split,
     recapitalization, extraordinary distribution, merger, consolidation,
     combination or exchange of shares of Common Stock or similar change or upon
     the occurrence of any other event that the Board, in its sole discretion,
     deems appropriate, the number of Option Shares and the Exercise Price shall
     be adjusted as appropriate.

          (c) In the event of a corporate merger, consolidation, acquisition of
     property or stock, separation, reorganization or liquidation (such event
     hereinafter referred to as a "Transaction"), the Board shall be authorized
     (i) to assume this Option by means of substitution of new options, as
     appropriate, (ii) to make provision, prior to the Transaction, for the
     acceleration of the vesting and exercisability of, or lapse of restrictions
     with respect to, this Option or (iii) in the event of a Transaction of
     which the Company is not the surviving corporation, to (A) cancel this
     Option and give the Optionee an opportunity to exercise for 30 days prior
     to such cancellation or (B) settle this Option by a cash payment equal to
     the difference between the Fair Market Value per share of Common Stock on
     the date of the Transaction and the exercise price of this Option,
     multiplied by the number of unexercised Option Shares.

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          9.   MISCELLANEOUS.   Nothing in this Option shall be deemed to create
any obligation on the part of the Board to nominate the Optionee for re-election
by the Company's shareholders.  The Company shall have the right to require,
prior to the issuance or delivery of any Common Stock upon exercise of this
Option, payment by the Optionee of any taxes required by law with respect to the
issuance or delivery of such shares.

          10.  SHAREHOLDER RIGHTS.  The Optionee shall have no rights of a
shareholder with respect to shares of Common Stock subject to the Option unless
and until such time as the Option has been exercised and ownership of such
shares of Common Stock has been transferred to the Optionee.

          11.  SUCCESSORS AND ASSIGNS.  This Agreement shall bind and inure to
the benefit of and be enforceable by the Optionee, the Company and their
respective permitted successors and assigns (including personal representatives,
heirs and legatees), except that the Optionee may not assign any rights or
obligations under this Agreement except to the extent and in the manner
expressly permitted herein.

          12.  GOVERNING LAW.  This Agreement shall be governed by, construed
and enforced in accordance with the laws of the State of Texas.


                              LYONDELL CHEMICAL COMPANY



Date:_____________            Signed:_______________________________

                              Name:_________________________________

                              Title:________________________________

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