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                                                                 Exhibit (e)(16)



                         SYBRON CHEMICAL INDUSTRIES INC.

                            SHARE PARTICIPATION PLAN

         THIS SHARE PARTICIPATION PLAN (the "Plan") is established as of this
lst day of June, 1990, by SYBRON CHEMICAL INDUSTRIES INC., a Delaware
corporation "SCI"), on behalf of itself and its direct and indirect
subsidiaries, for the benefit of certain of its employees and certain employees
of its direct and indirect subsidiaries (SCI and its direct and indirect
subsidiaries are hereinafter collectively referred to as the "Company"; the
employees of the Company are hereinafter collectively referred to as the
"Employees" and individually as "Employee").

                              W I T N E S S E T H:

         WHEREAS, SCI desires to provide a means of rewarding Employees for
their effort and service in contributing to an increase in the value of the
Company and, further, provide an incentive for those Employees to continue in
the employ of the Company or its successor following any possible change in
ownership.

         NOW, THEREFORE, SCI establishes the following Plan:

         1.       Definitions.  For purposes of this Plan:

             (a) "Share Participation Plan Award Pool" shall mean an amount
equal to the difference, if any, between (i) a sum equal to 2.0% of the net
amount of cash and the fair market value on the date of payment of any publicly
traded securities paid in consideration of a Triggering Event to the Company (if
the Triggering Event is as described in subparagraph (h)(i) below) or to the
shareholders of SCI (if the Triggering Event is as described in subparagraphs
(h)(ii) and (iii) below), at or within one year of the closing of such
Triggering Event, and (ii)

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2.0% of $2,593,000, which is the shareholder's equity of the Company as of
December 31, 1988. At the sole discretion of the Committee, the percentages set
forth in subparagraphs 1(a)(i) and 1(a)(ii) above may be increased in equivalent
amounts by up to 25% for a total percentage not to exceed 2.5%.

                  (b) "Award" shall mean the sum which an Awardee shall be
entitled to receive upon the occurrence of a Triggering Event, based upon his or
her Participation Percentage in the Share Participation Plan Award Pool.

                  (c) "Awardee" shall mean a person entitled to receive an Award
as a result of being a holder of Participation Shares at the time a Triggering
Event occurs.

                  (d) "Committee" shall mean a committee comprised of R. M.
Klein, S. H. Cohen, J. M. Rodriguez and S. R. Adler, or such other persons as
shall be appointed by the Board of Directors of SCI to serve in addition to, or
in lieu of, the aforementioned appointees.

                  (e) "Eligible Employees" shall mean those Employees who meet
the following requirements:

                           (i) have completed at least one full year of service
with the Company or are at the Executive Grade level; and

                           (ii) do not own or have options to purchase common
stock or preferred stock of SCI.

                  (f) "Participation Percentage" shall mean a fraction, the
numerator of which is the number of Participation shares held by an Awardee and
the denominator of which is the total number of Participation Shares held by all
Awardees.



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                  (g) "Participation Shares" shall mean participation shares in
the Share Participation Plan Award Pool as awarded pursuant to this Plan.

                  (h) "Triggering Event" shall mean:

                           (i) the sale of all or substantially all of the
assets of the Company to an unaffiliated third party;

                           (ii) the merger or consolidation of the Company with
or into an unaffiliated third party if, as a result thereof, the shareholders of
SCI prior to such merger or consolidation shall own less than 20% of all
outstanding voting securities of the entity or entities surviving the merger or
consolidation; or

                           (iii) a change in the beneficial ownership of more
than 80% of the voting securities of SCI within a 12-month period.

         2. Establishment of the Plan. The Company hereby establishes for the
benefit of its Eligible Employees this Plan pursuant to which Awardees shall be
entitled to share in the Share Participation Plan Award Pool upon the happening
of a Triggering Event, all in accordance with the terms and conditions
hereinafter set forth.

         3. Award of Participation Shares.

                  (a) The Committee shall have the right, at any time and from
time to time prior to the happening of a Triggering Event, to award
Participation Shares to any Eligible Employee. The Committee shall have full
discretion and authority to decide which Eligible Employees shall receive
Participation Shares and how many additional Participation Shares shall be
awarded to each such Eligible Employee. Without limiting the foregoing, Eligible
Employees who have derived more than 50% of their gross annual compensation from


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commissions or variable incentive plans will be limited in the number of
Participation Shares they will be entitled to receive, all as determined by the
Committee from time to time. The award of Participation Shares by the Committee
shall be final, conclusive and binding on the Company and the Employees.

                  (b) The Committee shall maintain a registry of all
Participation Shares awarded, which registry shall be final, conclusive and
binding on the Company and the Employees. If any Participation shares are
canceled in accordance with the provisions of subparagraph (c) below, the
Committee shall note such cancellation in the registry. At the discretion of the
Committee, Participation Shares may be evidenced by certificates. In no event,
however, shall the delivery of certificates impair upon the conclusiveness of
the registry as to the number of Participation Shares awarded and uncanceled.

                  (c) Participation Shares shall be canceled if, prior to the
happening of a Triggered Event, the holder thereof shall cease to be an Employee
for any reason whatsoever, including, without limitation, death, disability (as
shall be defined by the Committee), retirement or termination by the Company or
the holder except that if less than six (6) months prior to the Triggering
Event, an Employee retires in accordance with the retirement policies of the
Company or any successor thereof or is terminated by the Company or any
successor thereof for reasons other than cause (as hereinafter defined), such
Employee's Participation Shares shall not be canceled.

         4. Payment of Awards.

                  (a) Upon the happening of a Triggering Event, all Awardees
shall become entitled, subject to the provisions of subparagraph (b) below, to
receive their respective Awards.


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Payment of the Award to each Awardee shall be made on the first anniversary of
the Triggering Event, without interest, by the direct or indirect subsidiary of
SCI, or any successor thereof, employing such Awardee at the time of a
Triggering Event. Neither the amount of the Award nor the payment thereof shall
be taken into consideration in determining any thrift or pension contributions
or in connection with any other employee benefits, except as required by law or
otherwise determined necessary by the Company.

                  (b) The right to receive an Award shall be forfeited by an
Awardee if, prior to the first anniversary of the Triggering Event, such Awardee
shall cease to be an employee of the Company or any successor thereof for any
reason other than (i) death, (ii) disability (as shall be defined by the
Committee), (iii) retirement in due course in accordance with the retirement
policies of the Company or any successor thereof, or (iv) termination by the
Company or any successor thereof for reasons other than cause. For purposes of
this Plan, cause shall mean (A) an act of dishonesty by the Awardee constituting
a felony or other crime involving moral turpitude or resulting or intended to
result directly or indirectly in the Awardee's personal enrichment at the
Company's expense, (B) the willful engaging by the Awardee in misconduct which
is injurious to the Company, (C) habitual drunkenness or drug addiction, (D) the
refusal by the Awardee substantially to perform his duties, (E) the violation by
the Awardee of any express direction or reasonable rule or regulation
established by the Company from time to time regarding the conduct of the
business, and (F) any violation by the Awardee of the terms and conditions of
any employment or other agreement between the Awardee and the Company.

                  (c) In the event of the death of an Awardee, the Award to
which the deceased Awardee was entitled shall be payable to such beneficiary of
the Awardee as the Awardee shall


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have designated in the Awardee's Group Life Insurance policy or related Company
benefit. If the deceased Awardee did not designate a beneficiary as aforesaid,
or if the designated beneficiary predeceases the Awardee, the Award shall be
payable to the Awardee's estate.

         5. Partial Sale of the Company. In the event of the sale of the stock
or assets of a direct or indirect subsidiary or division of SCI which does not
constitute a Triggering Event (a "Partial Sale"), all Eligible Employees of such
subsidiary or other Eligible Employees who are designated to join the acquiring
entity of such subsidiary or division shall be deemed Awardees upon the
occurrence of a Partial Sale and shall be entitled to receive payment of their
Award on the first anniversary of a Triggering Event, as set forth in
subparagraph 4(a) above. Notwithstanding the foregoing, the right of any such
Awardee to receive his or her Award shall be forfeited if, prior to the first
anniversary of the Partial Sale, such Awardee shall cease to be an employee of
such subsidiary or division, or any successor thereof, for any reason other than
those set forth in subparagraphs 4(b)(i) through 4(b)(iv) (for purposes of this
Paragraph, all references in subparagraphs 4(b)(i) through 4(b)(iv) to the
Company shall be interpreted as referring to the subsidiary or division subject
to the Partial Sale).

         6. Transfers. Neither the Participation Shares nor any Award shall be
transferable by any Employee. Any attempt at assignment, transfer, pledge or
disposition of any Shares or Award contrary to the provisions hereof, or any
levy of execution, attachment or similar process upon any Shares or Award shall
result in cancellation of such Shares or the forfeiture of such Award.

         7. No Continued Employment. Neither the grant of Participation Shares
or Awards, nor anything herein contained, shall be construed to imply or
constitute a limitation on the right


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of the Company or any successor thereof to terminate the employment, services,
responsibilities, duties or authority of any Employee at any time and for any
reason whatsoever.

         8. No Shareholders' Rights. Neither the grant of Participation Shares,
nor anything herein contained, shall be interpreted as the issuance of any
equity or debt securities of the Company or any successor thereof or the grant
of any rights to vote, receive dividends, participate in meetings, share in the
Company's equity or any other right to which shareholders of a company may be
entitled.

         9. Withholding of Taxes. Whenever the company is required to make a
payment, the Company shall withhold all amounts sufficient to satisfy any
federal, state and/or local taxes or social contributions which the Company is
obligated to withhold in connection with such payment.

         10. Incapacity. If the Company determines that the Awardee or a
beneficiary entitled to receive any payments hereunder is under a legal
disability or is incapacitated in any way so as to be unable to manage his or
her financial affairs, the Company may discharge its obligation to make such
payments by making such payments to such person's personal representative.

         11. Governance and Interpretation of the Plan. The Committee shall have
the sole responsibility and authority for the governance, administration and
interpretation of this Plan; all decisions of the Committee respecting
governance, administration and interpretation of this Plan shall be binding,
final and conclusive upon the Company and all Employees.

         12. Plan Modifications and Termination. The Committee may modify this
Plan from time to time as it deems necessary to facilitate fair implementation
of the Plan and its objectives, subject to the approval of the Board of
Directors of SCI or any successor thereof. This Plan may


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be terminated by the Committee at any time after five (5) years from the date
hereof if a Triggering Event has not occurred, effective six (6) months after
the termination resolution of the committee is approved by the Board of
Directors of SCI or any successor thereof.

         IN WITNESS WHEREOF, SCI has established this Plan as of the day and
year first above written.


                                     SYBRON CHEMICAL INDUSTRIES INC.

                                     By:_________________________________
                                          Richard M. Klein, President


_________________________________
           WITNESS




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                         SYBRON CHEMICAL INDUSTRIES INC.
                            SHARE PARTICIPATION PLAN
                                 AMENDMENT NO. 1

         Sybron Chemical Industries Inc., a Delaware corporation (hereinafter
called the "Company") established, effective June 1, 1990, the "Sybron Chemical
Industries Inc. Share Participation Plan" (hereinafter called the "Plan").

         WHEREAS, the Committee desires to amend the Plan to provide that awards
of Participation Shares under the Plan may be reduced by a number or percentage
of Non-qualified Stock Options exercised under the Company's Stock Option Plan;
and

         WHEREAS, Paragraph 12 authorizes the Committee to the Plan to amend the
Plan, subject to the approval of the Board of Directors of the Company;

         NOW, THEREFORE, the Plan is hereby amended as follows:

         13. Paragraph 1, subparagraph (a) of the Plan is hereby amended by
adding at the end thereof the following new sentence:

                  "Notwithstanding anything contained in this subparagraph (a),
                  the Share Participation Plan Award Pool shall be reduced by an
                  amount equal to a fraction, the numerator of which is the
                  number of Participation Shares cancelled prior to or
                  coincident with a Triggering Event under Paragraph 3,
                  subparagraph (d) of the Plan, and the denominator of which is
                  the sum of (i) the total number of Participation Shares
                  outstanding at the time of the Triggering
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                  Event and (ii) the total number of Participation Shares
                  cancelled pursuant to subparagraph 3(d) of the Plan."

         14.      Paragraph 1, subparagraph (e)(ii) of the Plan is hereby
                  amended to read: "(ii) did not own or have options to purchase
                  common stock or preferred stock of SCI on June 1, 1990."

         15.      Paragraph 3 of the Plan is hereby amended by adding the new
                  subparagraph (d) to read:

                  "(d) If an Awardee is an Optionee in the Sybron Chemical
                  Industries Inc. 1992 Stock Option Plan (the "Stock Option
                  Plan") as defined therein, the Stock Option Plan Committee may
                  designate a number or percent of Participation Shares awarded
                  to the Awardee which will be cancelled prior to a Triggering
                  Event in conjunction with the exercise of a Nonqualified Stock
                  Option which has been granted to the Awardee pursuant to the
                  Stock Option Plan. The terms and conditions under which such
                  Participation Shares will be cancelled shall be set forth in
                  the Stock Option Grant Agreement (the "Agreement") made
                  between the Awardee and the Company. The Agreement may apply
                  to Participation Shares awarded to the Awardee before or after
                  the date of the Agreement but prior to the exercise of all or
                  a part of the Non-qualified Stock Option. Any such
                  cancellation shall be duly noted in the registry."



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         16.      The Plan in all other respects is hereby ratified and
                  confirmed.

         IN WITNESS WHEREOF, Sybron Chemical Industries Inc. has caused this
amendment to the Plan to be signed, effective ____________, 1992 and its
corporate seal to be hereunto affixed by its duly authorized officers this
_______ day of ____________, 1992.

                                        Sybron Chemical Industries Inc.

                                        By:_________________________________

ATTEST:

By:_________________________________
           (Corporate Seal)






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                                     ANNEX A

                              SYBRON CHEMICALS INC.

                            SHARE PARTICIPATION PLAN

                                 AMENDMENT NO. 2

         Sybron Chemicals Inc., a Delaware corporation (hereinafter called the
"Company") established, effective June 11, 1990, the "Sybron Chemical Industries
Inc. Share Participation Plan", renamed the "Sybron Chemicals Inc. Share
Participation Plan" (hereinafter the "Plan"). On ________, 1992, the Plan was
first amended through the adoption of Amendment No. 1.

         The Committee desires to further amend the Plan as hereinafter set
forth.

         NOW, THEREFORE, subject to the approval of the Board of Directors of
the Company, the Plan is hereby amended as follows:

         1. Paragraph 1, subparagraph (d) of the Plan is hereby amended to read
in its entirety as follows:

         "(d) "Committee" shall mean a committee comprised of R.M. Klein, S.F.
Ladin, J.H. Schroeder and S.R. Adler, or such other persons as shall be
appointed by the Board of Directors of SCI to serve in addition to, or in lieu
of, the aforementioned appointees."

         2. Paragraph 1, subparagraph (e)(i) of the Plan is hereby amended to
read in its entirety as follows:

                  "(i) have completed at least one full year of service with the
         Company or are at the Executive Grade level; provided that, after April
         1, 2000, the Committee shall have the discretion to waive such one-year
         requirement with respect to any Employee".
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         3. Paragraph 1, subparagraph (h) of the Plan is hereby amended to read
in its entirety as follows:

                  "(h) "Triggering Event" shall mean:

                           (i) the sale or disposal of substantially all of the
assets of the Company, or

                           (ii) the date any entity, person or group, within the
meaning of Section 13(d)(3) or Section 14(d)(2) of the Securities Exchange Act
of 1934, as amended, other than the Company or Citigroup or any of their
subsidiaries, any employee benefit plan (or related trust) sponsored or
maintained by the Company or any of its subsidiaries, or any other person or
group in which the present management of the Company shall have an aggregate
equity interest, on a fully diluted basis, of no less than 15%, shall have
become the beneficial owner of, or shall have obtained voting control over, more
than fifty percent (50%) of the outstanding shares of (A) the Company's Common
Stock, or (B) the Common Stock of the Company resulting from the merger or
consolidation of the Company with or into any other entity."

         4. Paragraph 3(d) of the Plan is hereby amended to read in its entirety
as follows:

                  "(d) If an Awardee is an Optionee in the Sybron Chemicals Inc.
         1992 Stock Option Plan (the "Stock Option Plan") as defined therein,
         the Stock Option Plan Committee may designate a number or percent of
         Participation Shares awarded to the Awardee which will be canceled
         prior to a Triggering Event in conjunction with the exercise of a Stock
         Option which has been granted to the Awardee pursuant to the Stock
         Option Plan. The terms and conditions under which such Participation
         Shares will be canceled shall be set forth in the Stock Option Grant
         Agreement (the "Agreement") made between the Awardee and the Company.
         The Agreement may apply to Participation


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         Shares awarded to the Awardee before or after the date of the Agreement
         but prior to the exercise of all or a part of the Stock Option. Any
         such cancellation shall be duly noted in the registry. Notwithstanding
         the foregoing, in no event shall Participation Shares awarded from and
         after April 1, 2000 be canceled as a result of the exercise of Stock
         Options granted pursuant to the Stock Option Plan."

         5. Paragraphs 4(a), 4(b) and 5 of the Plan are hereby amended by
replacing all references to the "first anniversary of the Triggering Event" with
the "sixth monthly anniversary of the Triggering Event".

         6. The Plan in all other respects is hereby ratified and confirmed.


         IN WITNESS WHEREOF, Sybron Chemicals Inc. has caused this amendment to
the Plan to be signed, effective April 1, 2000 and its corporate seal to be
hereunto affixed by its duly authorized officers this day of April, 2000.

                                      Sybron Chemicals Inc.

                                      By:_________________________________

ATTEST:

By:_________________________________
        (Corporate Seal)





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