NON-COMPETITION AND CONFIDENTIALITY AGREEMENT


      NON-COMPETITION AND  CONFIDENTIALITY  AGREEMENT  (Non-Compete  Agreement")
made the 30th day of September  1997 by and among Bio-  Reference  Laboratories,
Inc., a New Jersey  corporation  ("BRLI")**,  Marc D. Grodman,  Howard Dubinett,
Charles  T. Todd,  Jr. and Edward  Clayton,  key  employees  of BRLI  and/or its
GenCare Division and in the case of each of Messrs. Grodman,  Dubinett and Todd,
officers and significant shareholders of BRLI (hereinafter collectively referred
to as the "Employee/Shareholders"), and IMPATH INC., a Delaware corporation (the
"Purchaser").

                              W I T N E S S E T H:

      WHEREAS,  the Purchaser is purchasing  the customer list and certain other
assets  relating to the business of BRLI's  GenCare  Division  (the  "Business")
pursuant  to that  Agreement  and Bill of Sale dated as of the date  hereof (the
"Agreement")  between.  the  Purchaser and BRLI,  and the  Purchaser  desires to
protect the goodwill of the Business; and

      WHEREAS,  it is a material  inducement  to the  Purchaser  and a condition
precedent   to   the   closing   of   such    purchase   that   BRLI   and   the
Employee/Shareholders execute this Non-Compete Agreement.

      NOW,  THEREFORE,  for good and  valuable  consideration,  the  receipt and
sufficiency  of  which  is  hereby  acknowledged,  and in  consideration  of the
premises and the mutual  agreements  hereinafter set forth,  the parties hereto,
intending to be legally bound, hereby agree as follows:

      1. Incorporation of Recitals.  The foregoing recitals are incorporated in,
and shall  constitute an integral part of, this  Non-Compete  Agreement and this
Non-Compete Agreement shall be construed in light thereof.

      2.    Noncompetition.

            2.1 In order to induce the Purchaser to enter into the  transactions
contemplated  hereby,  and in  consideration  thereof,  each  of  BRLI  and  the
Employee/Shareholders  (each, a "Restricted  Party") for itself and for himself,
as the case may be, agrees that the Restricted  Party shall not, for a period of
thirty (30) months commencing on the date hereof (the "Restricted  Period"),  be
directly involved as hereinafter defined, in the solicitation of any "Restricted
Customer" to purchase any  "Restricted  Test" which is a  "Restricted  Test" for
such "Restricted Customer" as defined in Schedule III of the Agreement or in the
performance  of any  "Restricted  Test" for a "Restricted  Customer,"  except as
permitted by the provisions of Schedule III of the Agreement. The term "directly
involved" means, in the case of BRLI, solicitation by
- --------
      For purposes of this Non-Compete Agreement,  "BRLI" shall also include the
GenCare  Division  ("GenCare") and any  majority-owned  subsidiary or affiliated
entity of BRLI in which  BRLI has a 50% or  greater  ownership  interest  in the
assets,  income or equity, or any subsidiary or affiliated entity which BRLI has
by ownership of voting power, agreement or otherwise, the power to control.

                                      26





BRLI or by any BRLI officer, director, employee or other authorized party in its
behalf,  of a  "Restricted  Customer"  to purchase a  "Restricted  Test," or the
performance by BRLI or any such party in its behalf of a "Restricted Test" for a
"Restricted  Customer,"  during  the  "Restricted  Period."  The term  "directly
involved" means, in the case of each Employee/Shareholder, personal solicitation
of  a  "Restricted  Customer"  to  purchase  a  "Restricted  Test"  or  personal
performance  of a  "Restricted  Test" for a  "Restricted  Customer"  during  the
"Restricted Period," even if such Employee/Shareholder is employed by some other
entity. BRLI further agrees that in the event it acquires an interest during the
"Restricted Period" in any business which would be included in the definition of
BRLI as set forth as a footnote on page 1 of this  Non-Compete  Agreement,  such
business  shall,  after the date of the  acquisition and during the remainder of
the "Restricted Period," be subject to the same non-competition  restrictions as
BRLI pursuant to this Non-Compete  Agreement,  except to the extent permitted by
Schedule III to the Agreement.

            2.2 Each Restricted  Party agrees with the Purchaser that if, in any
proceeding,  the court or other  authority shall refuse to enforce the covenants
herein set forth  because such  covenants  cover too long a period of time,  any
such covenant shall be deemed appropriately amended and modified in keeping with
the intention of the parties to the maximum extent permitted by law.

      3.   Confidentiality,   Non-Disclosure   and  Ownership  of   Confidential
Information.  Each of BRLI  and each of the  Employee/Shareholders  acknowledges
that it or he has or will have access to, or  possession or knowledge of some or
all of the  following  confidential  information,  namely  (a) the  names of the
Restricted  Customers,  (b) the  special  prices  charged by BRLI or GenCare for
performance  of  Restricted  Tests for  Restricted  Customers to the extent such
prices differ from BRLI and GenCare's  published  prices for such tests, (c) the
amount of revenues for  Restricted  Tests  performed  by GenCare for  Restricted
Customers  during the three (3) month period ended June 30, 1997, (d) the number
of Restricted Tests and revenues derived  therefrom for Restricted  Customers to
be provided by the Purchaser to BRLI pursuant to Section 3(v) of the  Agreement,
together with related information (except to the extent required to be disclosed
by BRLI in order to enforce its rights under the  Agreement),  and (e) the terms
of the Agreement and Bill of Sale, the Transition Agreement and this Non-Compete
Agreement (hereinafter collectively called "Confidential Information").

            3.1  Neither of BRLI nor any of the  Employee/Shareholders  shall at
any time divulge,  reveal,  transfer,  reproduce,  sell, capitalize upon, use or
otherwise disclose any confidential information to any third party except to the
extent such  Confidential  Information  is legally  required to be disclosed (it
being  understood that the sales price and the nature of the Assets sold will be
publicly  disclosed by BRLI  pursuant to a press  release as well as  disclosure
documents  filed under the federal  securities  laws);  and except to the extent
such  Confidential  Information  is  required  to be  disclosed  to  those  BRLI
employees directly involved in servicing or billing  Restricted  Customers or in
determining  who the  Restricted  Customers  are in  order  to  comply  with the
Agreement  and Bill of  Sale,  the  Transition  Agreement  and this  Non-Compete
Agreement. In addition, each of BRLI and each of the Employee/Shareholders shall
exercise all reasonable efforts and

                                      27





precautions to protect Confidential  Information from misappropriation,  misuse,
disclosure,  breach of confidentiality,  or other conduct or action inconsistent
with the Purchaser's rights thereto.

            3.2 Confidential  Information shall not include: (a) any information
which is generally  available to the public through no breach of this Agreement;
and (b) any  information  which is lawfully  received  from a third party having
rights to disclose the same to BRLI or the Employee/Shareholder,  as applicable,
and as to which such third party is free from non-disclosure obligations.

            3.3   In  the   event   that   either   of   BRLI   or  any  of  the
Employee/Shareholders is required, by oral questions, interrogatories,  requests
for information or documents,  subpoena,  civil investigative  demand or similar
process,   to   disclose   any   Confidential    Information,    BRLI   or   the
Employee/Shareholder,  as the case may be,  shall  provide  the  Purchaser  with
prompt notice thereof so that the Purchaser may seek an  appropriate  protective
order and/or waive compliance by BRLI or the  Employee/Shareholder,  as the case
may be, with the provisions hereof;  provided,  however, that if, in the absence
of  a  protective  order  or  the  receipt  of  such  a  waiver,   BRLI  or  the
Employee/Shareholders  are,  in  the  opinion  of  counsel  for  the  Purchaser,
compelled  to  disclose  Confidential   Information  not  otherwise  disclosable
hereunder to any legislative,  judicial or regulatory body, agency or authority,
or else be  exposed  to  liability  for  contempt,  fine or  penalty or to other
censure, such Confidential Information may be so disclosed.

      4. Equitable  Relief. In the event of a breach or threatened breach of any
of  the   provisions  of  this   Agreement,   each  of  BRLI  and  each  of  the
Employee/Shareholders  hereby  consents and agrees that the  Purchaser  shall be
entitled  to an  injunction  or  similar  equitable  relief  from  any  court of
competent  jurisdiction  restraining  such person or entity from  committing  or
continuing any such breach or threatened breach or granting specific performance
of any act  required to be  performed by such person or entity under any of such
provisions,  without the  necessity  of showing any actual  damage or that money
damages would not afford an adequate remedy and without the necessity of posting
any bond or other security. Nothing herein shall be construed as prohibiting the
Purchaser  from  pursuing  any other  remedies at law or in equity  which it may
have.  The parties  hereto  agree that if in any  proceeding  the court or other
authority  shall refuse to enforce the  covenants  herein set forth because such
covenants  cover too long a period of time,  any such  covenant  shall be deemed
appropriately  amended and modified in keeping with the intention of the parties
to the maximum extent permitted by law.

      5.  Governing  Law. This  Agreement  shall be governed by and construed in
accordance  with  the laws of the  State  of New  York,  without  regard  to any
conflict  of laws  principles  thereof  which  would apply the laws of any other
jurisdiction.

      6. Titles.  Titles of the Sections of this  Agreement are intended  solely
for  convenience  and no  provision  of this  Agreement  is to be  construed  by
reference to the title of any Section.



                                      28




      7. Counterparts.  This Agreement may be executed in counterparts,  each of
which  shall be  deemed  an  original,  but all of which  taken  together  shall
constitute one and the same instrument.

      IN WITNESS WHEREOF, the parties hereto have executed this Agreement on the
date first above written.

                                    BIO-REFERENCE LABORATORIES, INC.


                                       By:
                                        Name: Howard Dubinett
                                        Title: Executive Vice President



                                                Marc D. Grodman



                                                Howard Dubinett



                                                Charles T. Todd, Jr.



                                                Edward Clayton


                                   IMPATH INC.


                                       By:
                                        Name: John P. Gandolfo
                                        Title: Executive Vice President

                                      29