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                               AMENDMENT NO. 1 TO
                  AMENDED AND RESTATED STOCKHOLDER'S AGREEMENT

                  AMENDMENT NO. 1 TO AMENDED AND RESTATED STOCKHOLDER'S
AGREEMENT (this "Amendment"), dated as of June 30, 2000, between ECOLAB INC., a
Delaware corporation (the "Company"), and HENKEL KOMMANDITGESELLSCHAFT AUF
AKTIEN, organized under the laws of the Federal Republic of Germany (the
"Stockholder").

                              W I T N E S S E T H:

                  WHEREAS, the Company and the Stockholder are party to that
certain Amended and Restated Stockholder's Agreement, dated as of June 26, 1991,
between the Company and the Stockholder (the "Stockholder's Agreement")
(capitalized terms used herein and not defined herein shall have the respective
meanings set forth in the Stockholder's Agreement); and

                  WHEREAS, the Company and the Stockholder have agreed to amend
certain provisions of the Stockholder's Agreement as set forth below.

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

                  1. ECONOMIC PARITY. Section 6 of the Stockholder's Agreement
is hereby amended and restated in its entirety as follows:

                  Section 6. ECONOMIC PARITY. If at any time during the
         Agreement Period any person or group acquires beneficial ownership of
         Voting Securities, whether pursuant to a tender or exchange offer made
         pursuant to Section 14(d) of the 1934 Act as to which the Company has
         recommended that its stockholders reject such offer or otherwise, such
         that such person or group beneficially owns more than 50% of the
         outstanding Voting Securities (a "Change in Control Transaction"), in
         addition to any other rights the Stockholder may have, the Stockholder
         shall have the right for a period of six months after such person or
         group acquires such beneficial ownership to deliver a notice relating
         to all, but not less than all, of the Shares then held by the
         Stockholder at that time (the "Notice Shares") to the Company. Within
         45 days following receipt of such notice, the Company shall pay to the
         Stockholder an amount of consideration, in either, at the Company's
         sole discretion, (i) cash or (ii) in the form of equity securities of
         the Company or any other consideration that would not result in any
         Shares held by the Stockholder being classified as a "redeemable equity
         security" pursuant to the Commission's Accounting Series Release No.
         268, having a value equal to the product of the number of Notice Shares
         times the positive difference between (i) the consideration per Share
         equal to the highest price per share paid by such person or group in
         acquiring Voting Securities and (ii) in the case of Notice Shares held
         by the Stockholder on the date of such payment, the Market Price

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         on the day before the payment and, in the case of Notice Shares sold by
         the Stockholder after the Change in Control Transaction and prior to
         such payment, the amount realized by the Stockholder pursuant to such
         dispositions, net of transaction costs (the aggregate amount being the
         "Aggregate Spread"). The Company shall indemnify and hold the
         Stockholder harmless against any adverse tax consequences suffered by
         the Stockholder as a result of the Company's payment to the Stockholder
         pursuant to the previous sentence as compared to the tax consequences
         of purchasing the Notice Shares at the consideration per share equal to
         the highest price per share paid by such person or group in acquiring
         Voting Securities. Such indemnification shall take the form of either,
         at the Company's sole discretion, (i) cash or (ii) equity securities of
         the Company or any other consideration that would not result in any
         Shares held by the Stockholder being classified as a "redeemable equity
         security" pursuant to the Commission's Accounting Series Release No.
         268. In the event that the Company determines to make a payment to the
         Stockholder pursuant to this Section 6 in a form of consideration other
         than cash, the Company shall provide an opinion to the Stockholder from
         an internationally recognized investment banking firm, mutually
         agreeable to both parties hereto, as to the value of such
         consideration. In addition, unless the Company arranges for the
         purchase of such securities from the Stockholder at a price at least
         equal to the Aggregate Spread, upon request of the Stockholder within
         45 days of such payment, the Company shall, within 90 days of such
         request, register the securities delivered as payment (the "Registered
         Securities") for resale by the Stockholder to the extent possible in an
         underwritten offering with an internationally recognized underwriter
         mutually agreeable to both parties. If the aggregate net proceeds to
         the Stockholder in such registered offering will be less than the
         Aggregate Spread, the Company shall deliver to the Stockholder either,
         at the Company's sole discretion, (i) cash equal to the amount by which
         the Aggregate Spread exceeds such net proceeds, or (ii) additional
         Registered Securities for resale in such registered offering in the
         amount required so that the aggregate net proceeds of such offering to
         the Stockholder equals the Aggregate Spread. In the event that the
         Company determines to make a payment to the Stockholder pursuant to
         this Section 6 in the form of cash, then the Company shall make such
         payment within such 45 day period to the extent funds are legally
         available therefor (and, if not then legally available therefor, as
         soon thereafter as such funds are legally available therefor).

                  2. REFERENCES. Upon the effectiveness of this Amendment, all
references in the Stockholder's Agreement and in all other agreements,
documents, certificates, schedules and instruments executed pursuant thereto to
the Stockholder's Agreement including, without limitation, references to "this
Agreement," "hereunder," "hereof," "herein" and words of like import contained
in the Stockholder's Agreement shall, except where the context otherwise
requires, mean and be a reference to the Stockholder's Agreement, as amended
hereby.

                  3. RATIFICATION. Except as expressly amended hereby, all of
the provisions of the Stockholder's Agreement, as amended hereby, shall remain
unaltered and in full force and effect,

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and, as amended hereby, the Stockholder's Agreement is in all respects agreed to
and ratified and confirmed by the parties hereto.

                  4. SEVERABILITY. If any provision of this Amendment shall be
declared by any court of competent jurisdiction to be illegal, void or
unenforceable, all other provisions of this Amendment shall not be affected and
shall remain in full force and effect.

                  5. COUNTERPARTS. This Amendment may be executed in one or more
counterparts, all of which shall be considered one and the same agreement and
each of which shall be deemed an original.

                  6. HEADINGS. The headings of the paragraphs of this Amendment
are inserted for convenience only and shall not constitute a part hereof or
affect in any way the meaning or interpretation of this Amendment.

                  7. GOVERNING LAW. This Amendment shall be construed under and
governed by the laws of the State of Delaware without regard to the
conflicts-of-laws provisions thereof.

                                 * * * * * * * *

                  IN WITNESS WHEREOF, the parties hereto have duly executed this
Amendment as of the date first above written.

                                 ECOLAB INC.

                                 By: /s/Allan L. Schuman
                                     ------------------------------------
                                 Name:    Allan L. Schuman
                                 Title:   Chairman of the Board, President and
                                             Chief Executive Officer


                                 HENKEL KOMMANDITGESELLSCHAFT AUF AKTIEN

                                 By: /s/Dr. Lothar Steinebach
                                     -------------------------------------
                                 Name:    Dr. Lothar Steinebach
                                 Title:   Senior Vice President

                                 By: /s/Thomas G. Kuhn
                                     -------------------------------------
                                 Name:   Thomas G. Kuhn
                                 Title:  Senior Corporate Counsel


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