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                                 EXHIBIT No. 10.45
                                                                 January 2, 1996



Carol P. Hanna
Controller and Director - Corporate Taxation
Applied Bioscience International Inc.
4350 North Fairfax Drive, Suite 300
Arlington, Virginia  22203

                          Re:     Key Employee Appreciation Plan

Dear Carol:

         As you are aware, on December 11, 1995, Applied Bioscience
International Inc. ("APBI") announced the engagement of Lehman Brothers to
assist in a strategic evaluation of whether shareholder value could be enhanced
through the separation of APBI's two core businesses, Pharmaco International
and ENVIRON.  As I have indicated to you, this evaluation is at a very
preliminary stage and at this point the separation of the business units is by
no means a foregone conclusion.  Having said this, it is clear that APBI is
going through a major transitional period which will include an ongoing
restructuring and reevaluation of APBI's corporate/finance function.  Because
of the uncertainty related to any transition of this nature, and APBI's
recognition of both your past contribution to the company, as well as the
importance of your continuing assistance during this transitional period, APBI
would like to continue your employment on the terms set forth herein.

1.       Terms of Continuing Employment.

         Set forth below are the terms and conditions of your continuing
         employment with APBI:

         A.      Employment and Duties.  APBI agrees to continue to employ you
                 and you agree to remain in the employ of APBI for the
                 Employment Term (as herein defined).  Unless otherwise agreed,
                 you will be employed  in your current position with
                 substantially the same duties and responsibilities that you
                 are currently performing in such position.

         B.      Compensation.

                 (i)      Your base salary and current bonus opportunities
                          during the Employment Term will remain at least as
                          high as their current level and will be subject to
                          periodic review and possible upward adjustment.

                 (ii)     In addition, if APBI is subject to a change of
                          control (as herein defined) you will receive a
                          one-time bonus equal to 35% of your annual base
                          salary.  This bonus would be paid to you within 30
                          days subsequent to a change of control.
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         C.      Employment Term.  The "Employment Term" shall mean the period
                 of your continuing employment with APBI commencing with the
                 date hereof and ending on the second anniversary of such date.
                 The Employment Term shall automatically be extended for
                 successive periods of one year each unless you notify APBI or
                 APBI notifies you by written notice delivered at least six
                 months prior to the end of the then current Employment Term
                 that the Employment Term is not to be extended.
                 Notwithstanding the foregoing, in the event of a change in
                 control you may elect to terminate your employment at any time
                 following the date 90 days subsequent to such change of
                 control.

         D.      Compensation Protection.

                 (i)      APBI reserves the right to terminate your employment
                          but, subject to subsection 1.D (ii) below, in the
                          event APBI exercises such right during the Employment
                          Term, APBI shall be obligated to continue to pay or
                          provide to you as severance the following:

                          (a)     your full base salary in accordance with
                                  APBI's normal payroll practices for the
                                  twelve-month period following your
                                  termination; provided that APBI's obligation
                                  to make such payment during the last six
                                  months of such period shall be mitigated on a
                                  dollar-for-dollar basis by any compensation
                                  you receive from your new employer, if any,
                                  during such period;

                          (b)     all employee benefits which you are receiving
                                  as of the date of your termination, including
                                  health and disability coverage for the
                                  twelve-month period following your
                                  termination; and

                          (c)     all stock options previously granted to you
                                  will vest as of the date of your termination.

                 (ii)     As we have previously discussed, in the event APBI's
                          two business units are separated there may be a
                          possibility that you will be offered comparable
                          employment (including comparable compensation and
                          benefits) in Arlington with either Pharmaco
                          International, ENVIRON or another successor entity.
                          If this occurs, and you elect to accept such
                          employment, the severance protection set forth in
                          Section 1.D(i) above will continue to apply for the
                          one-year period commencing with your employment with
                          such successor entity.  If you are offered such
                          comparable employment and you elect not to accept
                          such employment but are subsequently terminated by
                          APBI, your severance would be limited to your full
                          base salary for six months and you would only be
                          eligible to continue to receive employee benefits for
                          such six-month period.  Also, if you decide to
                          terminate your employment following a change of
                          control (as contemplated by Section 1C hereof) or if
                          you are terminated for cause, with cause being
                          defined as an act of fraud, embezzlement or theft in
                          connection with your duties, or a repeated failure to
                          follow the directions of APBI's Board of Directors or
                          APBI's Chief Executive Officer or Chief Financial
                          Officer, you would not
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                          be eligible to receive any severance or other
                          benefits otherwise contemplated herein.

         E.      Change of Control.  As used herein, "change of control" shall
                 have occurred if at any time during the Employment Term any of
                 the following events shall occur:

                 (i)      Any person, corporation, partnership or other similar
                          entity becomes the beneficial owner, directly or
                          indirectly, of securities of APBI representing fifty
                          percent or more of the combined voting power of
                          APBI's then outstanding securities;

                 (ii)     As a result of merger, consolidation, reorganization,
                          spin-off, stock sale or otherwise, APBI (or an
                          affiliate) owns less than 51% of the combined voting
                          power of the then-outstanding securities or other
                          equity interests of either Pharmaco LSR International
                          Inc. (i.e., Pharmaco International) or APBI
                          Environmental Sciences Group Inc. (i.e., ENVIRON); or

                 (iii)    Either Pharmaco LSR International Inc. or APBI
                          Environmental Sciences Group Inc. sells all or
                          substantially all of their respective assets to a
                          company in which APBI (or an affiliate) owns less
                          than 51% of the combined voting power of the
                          then-outstanding voting stock or equity interests.

2.       Miscellaneous.

         A.      Entire Agreement/Modification.  This agreement supersedes any
                 prior plans, agreements or understandings that have been given
                 to you.  No provision of this agreement may be modified,
                 waived or discharged except in writing signed by you and an
                 appropriate officer of APBI.

         B.      Governing Law.  This agreement shall be governed by the laws
                 of the Commonwealth of Virginia.

Since very few individuals are being offered ongoing employment on terms
similar to those contained herein, I expect you to keep this information
private and confidential.  Again, we appreciate your ongoing efforts on behalf
of APBI and hope that you find the employment terms offered hereby attractive.
We are requesting that you indicate your acceptance of such terms by
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signing two counterparts of this letter in the space provided below, with one
original to be returned to APBI and the other original retained in your
permanent records.


                                      Sincerely,

                                      APPLIED BIOSCIENCE INTERNATIONAL INC.


                                             By:    /s/ Stephen Waechter
                                                ------------------------
                                                  Stephen Waechter
                                                 Senior Vice President
                                                 Chief Financial Officer

Accepted and Agreed to:



Signature:    /s/ Carol P. Hanna
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Print Name:    Carol P. Hanna
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