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                                                               Exhibit 10.157

                    AMENDED AND RESTATED PROMISSORY NOTE

$18,000,000                                              October 17, 2000

     FOR VALUE RECEIVED, ENVIRON HOLDINGS, INC., a Delaware corporation, ENVIRON
INTERNATIONAL CORPORATION, formerly known as APBI Environmental Sciences Group,
Inc., a Virginia corporation, and ENVIRON FACILITY SERVICES CORPORATION, a
Virginia corporation (collectively referred to herein as "Maker"), jointly and
severally promise to pay to the order of APPLIED BIOSCIENCE INTERNATIONAL INC.,
a Delaware corporation (herein, together with any subsequent holder of this
Note, referred to as "Payee"), in lawful money of the United States of America,
the principal sum of Eighteen Million Dollars ($18,000,000), together with
interest in arrears on the unpaid principal balance at an annual rate equal to
eight percent (8%) (the "Rate"), in the manner and subject to the terms and
conditions set forth hereinbelow. Interest shall be calculated on the basis of
actual days elapsed over a 360-day year.

     This Note is the Restated Seller Note referred to in that certain Amendment
No. 3 to Credit and Security Agreement of even date herewith by and among Maker
and Payee, which amends that certain Credit and Security Agreement by and among
Environ Holdings, Inc., Environ International Corporation and Payee dated
February 2, 1999 (as thereafter amended, modified, restated, substituted,
extended and renewed at any time and from time to time, the "Credit Agreement"),
is one of the Credit Documents referred to in the Credit Agreement, and is
subject to the terms and conditions of the Credit Agreement, which are, by this
reference, incorporated herein and made a part hereof. However, neither this
reference to the Credit Agreement nor any provision thereof shall impair the
absolute and unconditional obligation of Maker to pay the principal and interest
on this Note as herein provided. Capitalized terms used in this Note without
definition shall have the  meanings set forth in the Credit Agreement.  This
Note amends and restates in its entirety that certain Promissory Note dated
February 2, 1999, from Environ Holdings, Inc. and Environ International
Corporation to Payee in the original principal amount of $18,000,000.00 (the
"Original Note").  It is expressly agreed that the indebtedness evidenced by the
Original Note has not been extinguished or discharged by this Note and is
included in the amount due to Payee from Maker.  Maker and Payee acknowledge and
agree that the outstanding principal balance on this Note as of the date hereof
is $18,000,000.00.

     This Note is subject to subordination as set forth in the Credit Agreement.

1.  PAYMENTS

    1.1  PRINCIPAL AND INTEREST

         (a) Interest only shall be payable on this Note until January 31, 2004,
when principal shall begin to be repaid in accordance with paragraph 1.1(b)
below. Prior to January 31, 2003, accrued interest on the outstanding principal
hereunder calculated at the Rate shall be due
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and payable in four (4) annual installments of One Million Four Hundred Forty
Thousand Dollars ($1,440,000), each payment due and payable on January 31 for
the years 2000-2003.

          (b)     Principal shall be repaid in eight (8) annual installments of
Two Million Two Hundred Fifty Thousand Dollars ($2,250,000), each payment being
due and payable on January 31 in the years 2004-2011, together with accrued
interest on the outstanding principal hereunder calculated at the Rate. All
principal and accrued interest shall be paid in full on or before January 31,
2011 (the "Maturity Date"). Partial payments made by Maker to Payee shall be
applied in such order as Payee may determine in Payee's discretion.


     1.2  MANNER OF PAYMENT

     All payments of principal and interest on this Note shall be made by
certified or bank cashier's check to Payee at 3151 Seventeenth Street Extension,
Wilmington, NC 28412, or at such other place in the United States of America as
Payee shall designate to Maker in writing or by wire transfer of immediately
available funds to an account designated by Payee in writing. All payments shall
be made without set-off, counterclaim or deduction of any kind. If any payment
of principal or interest on this Note is due on a day which is not a Business
Day, such payment shall be due on the next succeeding Business Day, and such
extension of time shall be taken into account in calculating the amount of
interest payable under this Note. "Business Day" means any day other than a
Saturday, Sunday or legal holiday in the State of North Carolina.

     1.3  PREPAYMENT

     This Note is subject to prepayment as set forth in the Credit Agreement.

2.   DEFAULTS

     2.1  EVENTS OF DEFAULT; REMEDIES

     Upon the failure of Maker to pay when due any payment of principal or
interest on this Note which failure continues for ten (10) days after the due
date thereof, or upon the occurrence of any other Event of Default, Payee may,
at its option, (i) by written notice to Maker, declare the entire unpaid
principal balance of this Note, together with all accrued interest thereon,
immediately due and payable regardless of any prior forbearance, (ii) exercise
any and all rights and remedies available to Payee under the Credit Documents,
and (iii) exercise any and all rights and remedies available to Payee under
applicable law, including, without limitation, the rights and remedies of a
secured party under the Uniform Commercial Code ("UCC") of the State of Virginia
or the UCC of any other jurisdiction whose law may govern the perfection of the
liens and security interests granted under the Credit Documents. Payee may
impose a late charge of five percent (5%) of the amount of any installment of
principal and/or interest not paid on or before the tenth (10/th/) day after
such installment is due. After the occurrence of an Event of Default or after
the maturity date hereof, the entire principal balance hereof, together with
accrued interest, shall bear interest at the rate of eleven percent (11%) per
annum. All rights and remedies of Payee for an Event of Default, whether granted
herein or otherwise, shall be

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cumulative and may be exercised singly or concurrently and/or from time to time
in Payee's discretion. Maker shall pay all reasonable costs and expenses
incurred by or on behalf of Payee in connection with Payee's exercise of any or
all of its rights and remedies under this Note, including, without limitation,
reasonable attorneys' fees and costs of collection.


     2.2  NOTICE BY MAKER

     Maker shall notify Payee in writing within five (5) days after the
occurrence of an Event of Default of which Maker acquires knowledge.

3.  MISCELLANEOUS

    3.1 WAIVER

    No waiver by Payee of any right or remedy under this Note shall be
effective unless in a writing signed by Payee. Neither the failure nor any delay
in exercising any right, power or privilege under this Note will operate as a
waiver of such right, power or privilege and no single or cumulative exercise of
any such right, power or privilege by Payee will preclude any other or further
exercise of such right, power or privilege or the exercise of any other right,
power or privilege. To the maximum extent permitted by applicable law, (a) no
claim or right of Payee arising out of this Note can be discharged by Payee, in
whole or in part, by a waiver or renunciation of the claim or right unless in a
writing, signed by Payee; (b) no waiver that may be given to Payee will be
applicable except in the specific instance for which it is given; and (c) no
notice to or demand on Maker will be deemed to be a waiver of any obligation of
Maker or of the right of Payee to take further action without notice or demand
as provided in this Note. Maker hereby waives presentment, demand, protest and
notice of dishonor and protest. Maker and all endorsers, sureties and guarantors
hereof hereby waive presentment for payment, demand, protest, notice of
nonpayment or dishonor, and any and all other notices and demands whatsoever,
and any and all defenses on the grounds of any extension of time for payment
which may be granted by Payee or any failure by Payee to assert any legal rights
available to Payee, and agree to remain bound until the entire indebtedness
evidenced by this Note is paid in full. Maker acknowledges the sufficiency and
receipt of the full consideration required of the Payee for this Note and that
this Note is the legal and binding obligation of each Maker enforceable in
accordance with its terms.

     3.2  NOTICES

     Any notice required or permitted to be given hereunder shall be given in
accordance with Section 7.08 of the Credit Agreement.

     3.3  SEVERABILITY

     If any provision in this Note is held invalid or unenforceable by any court
of competent jurisdiction, the other provisions of this Note will remain in full
force and effect. Any provision of this Note held invalid or unenforceable only
in part or degree will remain in full force and effect to the extent not held
invalid or unenforceable.

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     3.4  GOVERNING LAW

     This Note will be governed by the laws of the State of Virginia without
regard to conflicts of laws principles and without regard to the location of any
Maker, any guarantor hereof, or of any properties or assets granted as security
for this Note.

     3.5  PARTIES IN INTEREST

     This Note shall bind each Maker and its successors and assigns and inure to
the benefit of Payee and its successors and assigns. No Maker may assign its
rights or obligations hereunder without the prior written consent of Payee.

     3.6  SECTION HEADINGS; CONSTRUCTION

     The headings of Sections in this Note are provided for convenience only and
will not affect its construction or interpretation. All references to "Section"
or "Sections" refer to the corresponding Section or Sections of this Note unless
otherwise specified. All words used in this Note will be construed to be of such
gender or number as the circumstances require. Unless otherwise expressly
provided, the words "hereof" and "hereunder" and similar references refer to
this Note in its entirety and not to any specific section or subsection hereof.
This Note may not be amended, changed or modified in any respect except by a
written document which has been executed by Maker and Payee.

     3.7  TIME OF THE ESSENCE

     Time is of the essence with respect to all dates and time periods set forth
in this Note.

     3.8. JOINT AND SEVERAL LIABILITY

     The obligations and liabilities of Environ Holdings, Inc., Environ
International Corporation and Environ Facility Services Corporation  are the
joint and several obligations of each of them.

     3.9  MUTUAL WAIVER OF JURY TRIAL

     Maker and Payee waive all rights to trial by jury of any claims of any kind
arising under or relating in any way to this Note or to the other Credit
Documents. Maker and Payee acknowledge that this is a waiver of a legal right
and represent to each other that these waivers are made knowingly and
voluntarily after consultation with counsel of their choice. Maker and Payee
agree that all such claims shall be tried before a judge of a court having
jurisdiction without a jury.

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     IN WITNESS WHEREOF, and intending to be legally bound hereby, Maker
executes this Note under seal as of the date first written above.



WITNESS:                             ENVIRON HOLDINGS, INC.,
                                     a Delaware corporation

/s/ Margaret Breyer                  By: /s/ Joseph Highland
----------------------                   --------------------------------(SEAL)
                                         Name: Joseph Highland              .
                                               --------------------------
                                         Title: Chairman, Chief Executive
                                                Officer & Secretary
                                                --------------------------  .

                                     ENVIRON INTERNATIONAL CORPORATION,
                                     a Virginia corporation

/s/ Margaret Breyer                  By: /s/ Joseph Highland
----------------------                   ---------------------------------(SEAL)
                                         Name:  Joseph Highland
                                                --------------------------  .
                                         Title: Chairman, Chief Executive
                                                Officer & Secretary
                                                --------------------------  .


                                     ENVIRON FACILITY SERVICES CORPORATION,
                                     a Virginia corporation

/s/ Margaret Breyer                  By: /s/ Joseph Highland
----------------------                   ---------------------------------(SEAL)
                                         Name:  Joseph Highland
                                                --------------------------  .
                                         Title: Chairman, Chief Executive
                                                Officer & Secretary
                                                --------------------------  .

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