<PAGE>

                                                                EXHIBIT 10.18(e)

                                                                  EXECUTION COPY

                               THIRD AMENDMENT TO
                         RECEIVABLES PURCHASE AGREEMENT

         THIS THIRD AMENDMENT TO RECEIVABLES PURCHASE AGREEMENT, dated as of
March 18, 2003 (this "Amendment"), is entered into by and among ARCH CHEMICALS
RECEIVABLES CORP., as seller (the "Seller"), ARCH CHEMICALS, INC., as the
servicer (the "Servicer"), BLUE RIDGE ASSET FUNDING CORPORATION, as a purchaser
("Blue Ridge") and WACHOVIA BANK, NATIONAL ASSOCIATION (f/k/a Wachovia Bank,
N.A.), as the Agent. Capitalized terms used and not otherwise defined herein are
used as defined in the Agreement (as defined below and amended hereby).

         WHEREAS, the parties hereto have entered into that certain Receivables
Purchase Agreement, dated as of March 19, 2002 (as amended, restated,
supplemented or otherwise modified to the date hereof, the "Agreement");

         WHEREAS, the parties hereto desire to amend the Agreement in certain
respects as hereinafter set forth;

         NOW THEREFORE, in consideration of the premises and the other mutual
covenants contained herein, the parties hereto agree as follows:

         SECTION 1.1 AMENDMENTS.

         The Agreement is hereby amended as follows:

         (a)      Section 9.1(h) is hereby deleted and replaced with the
following:

                           "(h)     As at the end of any Calculation Period:

                                    (i)      the three-month rolling average
                                             Delinquency Ratio shall exceed
                                             3.0%,"

                                    (ii)     the three-month rolling average
                                             Default Ratio shall exceed 2.5% or
                                             such other amount as may be
                                             determined from time to time
                                             pursuant to Section 9.3, or

                                    (iii)    the three-month rolling average
                                             Dilution Ratio shall exceed 5.9% or
                                             such other amount as may be
                                             determined from time to time
                                             pursuant to Section 9.3."

         (b)      A new Section 9.3 is hereby added as follows:

                           "Section 9.3. Determination of Trigger Ratios.

<PAGE>

                                    The Seller and the Servicer agree, that,
                           because the percentages set forth in Sections
                           9.1(h)(ii) and (iii) have been established based upon
                           estimates provided by the Servicer and that the
                           actual performance of the pool of Receivables may
                           differ from those estimates, the Agent may, from time
                           to time after the June 2003 Monthly Reporting Date,
                           in its sole credit judgment, based upon reasonable
                           analysis of the actual amounts of Defaulted
                           Receivables and Dilutions reported in the Monthly
                           Reports, change the percentages set forth in Sections
                           9.1(h)(ii) and/or (iii); provided, however, that the
                           Agent may not, prior to January 15, 2004, pursuant to
                           this Section 9.3, reduce the percentage set forth in
                           Section 9.1(h)(ii) below 2.2% or the percentage set
                           forth in Section 9.1(h)(iii) below 4.9%. The Agent
                           shall provide the Seller and the Servicer with prior
                           notice of each such change, each such change to take
                           effect on the effective date therefor as set forth in
                           such notice; provided, however, that no such change
                           shall take effect retroactively."

         (c)      Section 10.2 is hereby amended by adding the following new
sentence at the end thereof:

                           "For avoidance of doubt, any interpretation of
                  Accounting Research Bulletin No. 51 by the Financial
                  Accounting Standards Board shall constitute an adoption,
                  change, request or directive subject to this Section 10.2."

         (d)      Subclause (A) of clause (i) of the definition of "Eligible
Receivable" is hereby amended by deleting such subclause and replacing it with
the following:

                  "(A) if a natural person, is a resident of the United States
                   or, if a corporation or other business organization, is
                   organized under the laws of the United States or any
                   political subdivision thereof or under the laws of any
                   Province of Canada (excluding the Provinces of Quebec, New
                   Brunswick, Nova Scotia and Newfoundland) and has its chief
                   executive office in the United States or any Province of
                   Canada (excluding the Provinces of Quebec, New Brunswick,
                   Nova Scotia and Newfoundland);"

         (e)      Clause (i) of the definition of "Liquidity Termination Date"
is hereby deleted and replaced with the following:

                           "(i) the earlier of (A) January 15, 2004 or such
                  later date as the Liquidity Banks may agree in their sole
                  discretion, but not later than 364 days following the then
                  Purchase Termination Date (as such term is defined in the
                  Liquidity Agreement) and (B) the date on which the Liquidity
                  Bank's Liquidity Commitments otherwise cease to be available
                  to Blue Ridge or otherwise cease to be in full force and
                  effect; or"

                                      -2-
<PAGE>

         (f)      The definition of "Obligor Concentration Limit" in Exhibit I
to the Agreement is hereby amended by deleting the table set forth therein and
replacing it with the following:

<TABLE>
<CAPTION>
                                                                    Allowable % of Eligible
           S&P Rating                     Moody's Rating                  Receivables
--------------------------------    -------------------------       -----------------------
<S>                                 <C>                             <C>
               A-1+                            P-1                            10%
               A-1                             P-1                             8%
               A-2                             P-2                             6%
               A-3                             P-3                           3.5%
Below A-3 or Not Rated by either    Below P-3 or Not Rated by                3.0%
         S&P or Moody's               either S&P or Moody's
</TABLE>

         (g)      The definition of "Receivable" in Exhibit I to the Agreement
is hereby amended by adding the following phrase at the end of the first
sentence thereof and before the period:

                  "; provided, however, that in each case the Obligor of such
                  indebtedness or other obligation is domiciled in the United
                  States of America or in Canada (excluding the Provinces of
                  Quebec, New Brunswick, Nova Scotia and Newfoundland)"

         (h)      Clause (i) of the definition of "Required Reserve Factor
Floor" in Exhibit I to the Agreement is hereby amended and restated to read as
follows:

                  "(i) 12% (provided that for each Calculation Period from March
                  to and including August of each calendar year, the percentage
                  shall be 18% instead of 12%), plus"

         SECTION 1.2 REFERENCE TO AND EFFECT ON THE AGREEMENT AND THE RELATED
DOCUMENTS.

         (a)      Upon the effectiveness of this Amendment, (i) each of the
Seller Parties hereby reaffirms all representations and warranties made by it in
Article V of the Agreement (as amended hereby) and agrees that all such
covenants, representations and warranties shall be deemed to have been remade as
of the effective date of this Amendment, (ii) each of the Seller Parties hereby
represents and warrants that no Amortization Event or Unmatured Amortization
Event shall have occurred and be continuing and (iii) each reference in the
Agreement to "this Agreement", "hereunder", "hereof", "herein" or words of like
import shall mean and be, and any references to the Agreement in any other
document, instrument or agreement executed and/or delivered in connection with
the Agreement shall mean and be, a reference to the Agreement as amended hereby.

         (b)      The Seller hereby agrees that in addition to any costs
otherwise required to be paid pursuant to the Transaction Documents, the Seller
shall pay the reasonable legal fees and out-of pocket expenses of the Agent's
counsel, Hunton & Williams, and all audit fees and due diligence costs incurred
by the Agent in connection with the consummation of this Amendment.

                                      -3-
<PAGE>

         SECTION 1.3 EFFECTIVENESS AND EFFECT.

         This Amendment shall be effective on the day (the "Amendment Effective
Date") on which the last to occur of the following: (i) execution by the Seller
Parties of this Amendment, (ii) execution of the First Amendment to the
Receivables Sale Agreement, dated as of the date hereof, by each of the parties
thereto; (iii) execution of the Amended and Restated Fee Letter, dated the date
hereof, by each of the Seller Parties and (iv) payment of all amounts required
to be paid to the Agent on the Amendment Effective Date under the Amended and
Restated Fee Letter. Except as otherwise amended by this Amendment, the
Agreement shall continue in full force and effect and is hereby ratified and
confirmed.

         SECTION 1.4 GOVERNING LAW.

         This Amendment will be governed by and construed in accordance with the
laws of the State of New York.

         SECTION 1.5 SEVERABILITY.

         Each provision of this Amendment shall be severable from every other
provision of this Amendment for the purpose of determining the legal
enforceability of any provision hereof, and the unenforceability of one or more
provisions of this Amendment in one jurisdiction shall not have the effect of
rendering such provision or provisions unenforceable in any other jurisdiction.

         SECTION 1.6 COUNTERPARTS.

         This Amendment may be executed in one or more counterparts, each of
which shall be deemed to be an original, but all of which together shall
constitute one and the same instrument. Delivery of an executed counterpart of a
signature page by facsimile shall be effective as delivery of a manually
executed counterpart of this Amendment.

                                      -4-
<PAGE>

         IN WITNESS WHEREOF, the parties have caused this Amendment to be
executed by their respective officers thereunto duly authorized, as of the date
first above written.

                                    ARCH CHEMICALS RECEIVABLES CORP.,
                                    as the Seller

                                    By: /s/ W. Paul Bush
                                        ----------------------------------------
                                        Name: W. Paul Bush
                                        Title: Treasurer

                                    ARCH CHEMICALS, INC.,
                                    as the Servicer

                                    By: /s/ W. Paul Bush
                                        ----------------------------------------
                                        Name: W. Paul Bush
                                        Title: Treasurer

                        [additional signatures to follow]

<PAGE>

                                    BLUE RIDGE ASSET FUNDING
                                    CORPORATION,
                                    as a Purchaser

                                      by Wachovia Securities, Inc.,
                                        as Attorney-in-Fact

                                    By: /s/  Douglas R. Wilson, Sr.
                                        ----------------------------------------
                                      Name: Douglas R. Wilson, Sr.
                                      Title: Vice President

                                    WACHOVIA BANK,
                                    NATIONAL ASSOCIATION,
                                    as Agent

                                    By: /s/  Elizabeth R. Wagner
                                        ----------------------------------------
                                       Name: Elizabeth R. Wagner
                                       Title: Director

                               [end of signatures]