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                      SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C. 20549

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                              Amendment No. 7 to
                                  SCHEDULE TO
                 Tender Offer Statement under Section 14(d)(1)
              or 13(e)(1) of the Securities Exchange Act of 1934

                                      and

                              Amendment No. 7 to
                                 SCHEDULE 13D
                   under the Securities Exchange Act of 1934

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                             Sybron Chemicals Inc.
                      (Name of Subject Company (Issuer))

                       Project Toledo Acquisition Corp.
                               Bayer Corporation
                           Bayer Aktiengesellschaft
                     (Names of Filing Persons (Offerors))

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                    COMMON STOCK, PAR VALUE $.01 PER SHARE
                        (Title of Class of Securities)

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                                   870903101
                     (Cusip Number of Class of Securities)
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                           Bruce A. Mackintosh, Esq.
                               Bayer Corporation
                                100 Bayer Road
                           Pittsburgh, PA 15205-9741
                           Telephone: (412) 777-2000
                    (Name, address and telephone number of
                     person authorized to receive notices
                and communications on behalf of filing persons)

                                   Copy to:

                          Daniel P. Cunningham, Esq.
                            Cravath, Swaine & Moore
                               825 Eighth Avenue
                         New York, New York 10019-7475
                           Telephone: (212) 474-1000

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                               October 26, 2000

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[ ] Check the box if the filing relates to preliminary communications made
before the commencement of a tender offer.

Check the appropriate boxes below to designate any transactions to which the
statement relates:

[X] third-party tender offer subject to Rule 14d-1.
[ ] issuer tender offer subject to Rule 13e-4.
[ ] going-private transaction subject to Rule 13e-3.
[X] amendment to Schedule 13D under  Rule 13d-2.

Check the following box if the filing is a final amendment reporting the
results of the tender offer: [X]

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     Project Toledo Acquisition Corp., a Delaware corporation (the
"Purchaser"), Bayer Corporation, an Indiana corporation ("Parent"), and Bayer
Aktiengesellschaft, a company organized under the laws of the Federal Republic
of Germany ("Bayer AG"), hereby amend and supplement their Tender Offer
Statement on Schedule TO (the "Schedule TO") and their Schedule 13D, in each
case, originally filed on September 8, 2000. The Schedule TO relates to the
offer by the Purchaser to purchase all outstanding shares of common stock, par
value $.01 per share (the "Shares"), of Sybron Chemicals Inc., a Delaware
corporation (the "Company"), together with the associated rights (the
"Rights") to purchase Series A Junior Participating Preferred Stock pursuant
to the Rights Agreement, at $35 per Share, net to the seller in cash, without
interest thereon, upon the terms and subject to the conditions set forth in
the Offer to Purchase dated September 8, 2000 (the "Offer to Purchase"), and
in the related Letter of Transmittal. Capitalized terms used, and not
otherwise defined, herein have the meanings assigned thereto in the Offer to
Purchase.

Item 11. Additional Information.

     Item 11 to the Schedule TO is hereby amended and supplemented by the
following:

     On October 23, 2000, the Purchaser accepted for payment, and paid for,
5,660,116 Shares. On October 26, 2000, the Purchaser accepted for payment an
additional 47,818 Shares delivered pursuant to Notices of Guaranteed Delivery.



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                                  SIGNATURES

     After due inquiry and to the best of my knowledge and belief, I certify
that the information set forth in this statement is true, complete and
correct.

                                     PROJECT TOLEDO ACQUISITION CORP.,

                                     By: /s/ John L. Williams
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                                        Name:  Dr. John L. Williams
                                        Title: President

                                     BAYER CORPORATION,

                                     By: /s/ E.L. Foote, Jr.
                                        --------------------------------------
                                        Name:  E.L. Foote, Jr.
                                        Title: Executive Vice President


                                     BAYER AKTIENGESELLSCHAFT,

                                     By: /s/ Roland Hartwig
                                        --------------------------------------
                                        Name:  Dr. Roland Hartwig
                                        Title: General Counsel

Dated:  October 26, 2000