Exhibit 10.b
                              EMPLOYMENT AGREEMENT

                                     Between

                                KENNETH L. MINTON

                                       and

                    PML MICROBIOLOGICALS, INC. and PML, INC.


       The purpose of this  Agreement is to confirm the terms of the  employment
relationship  between PML  Microbiologicals,  Inc.  and PML,  Inc.  (hereinafter
referred to as "Employer" or "PML"), and Kenneth Minton (hereinafter referred to
as the "Employee").

       I. Term of Agreement.  Employer and Employee  agree that the term of this
Agreement  shall be from the day of execution by all parties until May 31, 2002,
unless employment is sooner terminated as provided herein.

       1.1.  Position and Duties.

               1.1.1  Employer and Employee agree that Employee will be employed
as  the  President  and  CEO  of PML  and  that  in  this  capacity,  Employee's
responsibilities will include, but are not limited to those described in Exhibit
A, attached hereto and incorporated  herein by this reference.  It is understood
that from time to time  Employee  may be  assigned  other  duties in addition to
those  described in Exhibit A. It is further agreed and  understood  that as the
President/CEO  of Employer,  the hours which Employee is required to work,  will
vary  considerably and will sometimes be more and sometimes less than forty (40)
hours per week.  It is  understood  and agreed that  Employee's  pay will not be
affected by the number of hours worked in a given week; Employee is not eligible
for overtime compensation nor subject to deductions from compensation due to any
variance in the number of hours worked.

               1.1.2  Unless  agreed  otherwise,  Ron Torland will meet with the
Employee on Wednesdays at 3:00 p.m. in the conference room at PML.

               1.1.3  Employee's  obligation to devote his full-time,  attention
and energy to the  business of Employer  shall not be  construed  as  preventing
Employee  from  investing  his  assets so long as any such  investment  will not
require any services on the part of Employee in the  operation of the affairs of
the company(ies) or business(es) in which such investment(s) is (are) made.

       2. Employee shall have the authority to hire and fire other  employees of
Employer under his supervision.

       3 . Employer's Covenants.

               3.1  Employer  agrees to reimburse  Employee  for all  reasonable
business  expenses incurred by Employee while on Employer's  business.  Employee
shall maintain such records as will be necessary to enable  Employer to properly
deduct such items as business expenses when computing  Employer's federal income
tax.

               3.2 Employer agrees to conduct performance reviews of Employee on
a periodic  basis during  Employee's  first six months of  employment  and on an
annual basis thereafter.

       4 . Compensation.


<PAGE>
               4.1 For all services  rendered by Employee  under this  Agreement
(exclusive of stock options and bonus,  if any),  Employer  shall pay Employee a
base salary of One Hundred Fifty Thousand Dollars ($150,000) per year, until May
31, 1999 and then increased to $175,000  effective June 1, 1999.  Employee shall
be paid this salary on PML's regular pay days,  minus all lawful and agreed upon
payroll deductions.

               4.2   Unpaid   compensation   due   to   short-term   cash   flow
considerations  shall be accrued by Employee  without payment of interest if not
paid when due.

       5 . Bonuses.

               5.1 Goal. To maximize  shareholder  value. The Board of Directors
of PML  proposes  the  following  plan  for the  term of the  contract  with the
understanding  that the bonus  after  that  period  will  likely  be based  upon
Economic Value Added (EVA) according to a formula yet-to-be determined.

               5.2 Basis.  Fifty  percent of pre-tax  profits  above the base of
$360,000,   with  a  maximum  bonus  of  $100,000.   Employer   profit   sharing
contributions,   401(k)  matching  contributions  and  expenses  resulting  from
issuance of  non-qualified  stock options are added back to pre-tax  profits for
calculations of bonus amount.

               5.3 Term.  There will be no bonus paid for the fiscal year ending
May 31, 1996.  Any bonus for any other fiscal year in which Employee is employed
under the terms of this Agreement shall be calculated as set forth herein.

               5.4 Calculation.  Pre-tax profits - Less debt forgiveness, if any
- Less base ($360,000) = Profits to be used for base calculation

                           Example: $750,000  Pre-tax profits
                                    (100,000) Debt forgiveness
                                    (360,000) Base
                                =   $290,000 Profits for base calculation

                                    $145,000 50% of applicable profits
 
                                    $100,000 Bonus paid (Bonus is based upon 50%
                                                        of profits over $360,000
                                                        up to a maximum bonus of
                                                                       $100,000)

               5.5 Earning and Payment of Bonus. Two-thirds of the bonus for any
fiscal year  (other  than  fiscal  year 1996,  which will have no bonus) will be
earned at the close of the fiscal  year for which the  pre-tax  profits  were at
least $360,000,  as certified by the auditors.  Said earned portion of the bonus
will be paid within ten days of the  certification  of the annual audit  results
for the fiscal year for which the bonus is being calculated.

               One-third  of the bonus will be earned at the close of the fiscal
year  immediately  following  the  fiscal  year  for  which  the  bonus is being
calculated,  providing  that the pre-tax  profits are at least $360,000 for that
fiscal  year.  That earned  portion of the bonus will be paid within ten days of
the  certification of the annual audit results for the fiscal year for which the
bonus is being calculated.

               If PML's  pre-tax  profits  are less than  $360,000 in any fiscal
year, any bonus payment or portion of bonus payment unpaid from the prior fiscal
year will be deemed unearned and will not be paid.

               5.6  Forfeiture of Bonus.  No unearned  bonus or portion of bonus
will be paid if any of the following circumstances exist:
<PAGE>
               5.6.1 Employee quits PML at any time other than at the expiration
of the contract.

               5.6.2  Employee  is fired for  cause,  as that term is defined in
paragraphs 10.1.1 through 10.1.4.


               5.7 Payment of Bonus in Event of Termination Without Cause.

               5.7.1 If Employee is  terminated  at the close of any fiscal year
without "cause" as that term is defined in Paragraphs 10.1.1 and 10.1.4,  and if
the terms and conditions of Paragraphs  5.2, 5.3, 5.4 and 5.5 are met,  Employee
will  receive  payment  of his  bonus,  if any,  for  his  last  fiscal  year of
employment subject to and under the terms and conditions contained herein.

               5.7.2 If Employee is terminated at any other time without "cause"
as that term is defined in Paragraph  10.1,  and if the terms and  conditions of
Paragraphs 5.2, 5.3, 5.4 and 5.5 are met, Employee will receive a pro rata share
of his bonus, if any, for whatever portion of the last fiscal year of employment
and subject to and under the terms and conditions contained herein.

                           Example.  If Employee is terminated  without cause on
                           November 1, 1997,  and if the pre-tax  profits of the
                           Employer  were greater  than  $360,000 in fiscal year
                           ending May 31, 1998,  then  Employee  shall receive a
                           bonus  equal to  5/12ths of  whatever  bonus he would
                           have  been  entitled  to had  he  worked  the  entire
                           1997-1998  fiscal  year.  Two-thirds  of the pro rata
                           bonus  shall be paid ten (10)  days  after  the audit
                           results are  certified for fiscal year ending May 31,
                           1998 (approximately  August,  1998) and one-third ten
                           days after the audit  results are  certified  for the
                           following fiscal year (approximately  August,  1999),
                           assuming  the  pre-tax  profits  for the fiscal  year
                           ending May 31, 1999, are greater than $360,000.

               Payment of any bonus under  Paragraph  5.7 will be subject to the
provisions of Paragraph 11.4.

       6 . Stock Options.

               6.1 Employee will be eligible for a total of 140,000  shares over
a period of six years.

                  Shares   Price                              Date of vesting
                  20,000   Fair market value,
                                    date of grant                      4/8/96
                  20,000   Same                                        5/31/97
                  20,000   Same                                        5/31/98
                  20,000   Same                                        5/31/99
                  20,000   Same                                        5/31/00
                  20,000   Same                                        5/31/01
                  20,000   Same                                        5/31/02

               6.2  Except as to those  options  which have  already  vested and
subject to the  provisions  of  paragraph  6.3,  Employee's  rights to any stock
option cease on the date of Employee's termination. Employee must be employed on
the date of vesting in order to receive his option.

               6.3 In the event of a termination  without  cause,  as defined in
paragraphs  10.1.1-10.1.4,  or a sale of a  controlling  interest  in PML during
Employee's employment, all options vest immediately.
<PAGE>
               6.4 Employee  agrees to be bound by the terms and  conditions  of
the MEDA, Inc. 1994 Stock Option Plan.

       7 . Fringe Benefits.

               7.1 Fringe Benefits.  Employer and Employee agree that during the
term of this Agreement,  Employee shall be entitled to participate in all fringe
benefits as may be authorized  and adopted from time to time by Employer and for
which Employee is eligible.

               7.2  Miscellaneous  Expense.  Employer  shall pay for  Employee's
membership dues in professional  organizations  and reimbursement for courses up
to a reasonable annual amount and as Employer's  finances permit,  provided that
the benefit to Employer of such organization or course can be demonstrated.

         8 .  Vacation  and Sick Leave.  Employee  shall be entitled to four (4)
weeks paid vacation per year. Vacation is earned based on Employee's anniversary
date.  Employee  shall  earn  sick  leave  pursuant  to the  policies  generally
available to PML's employees.

               8.1 Carryover Unused  Vacation.  Employee may accrue a maximum of
240 hours. No further  vacation will accrue beyond 240 hours until Employee uses
some accrued vacation time.

               8.2 Scheduling. Vacation shall be scheduled by Employer at a time
mutually convenient to both Employer and Employee.

               8.3 Accrued and Unused Vacation at Termination. In the event this
Agreement  is  terminated  before  its  expiration  date by either  Employer  or
Employee,  Employee shall be paid for all previously accrued and unused vacation
time.

       9 . Confidential Information and Non-Solicitation.

               9.1 It is  understood  and agreed that as a result of  Employee's
employment  with PML,  Employee will be acquiring and making use of confidential
information  about Employer's  business as well as financial  information  about
PML.  Employee  agrees that he will respect the confidences of Employer and will
not at any time during or after his employment with PML,  directly or indirectly
divulge or disclose for any purpose  whatsoever or use for his own benefit,  any
confidential information that has been obtained by or disclosed to Employee as a
result of his employment with PML.

               9.2 Employee  agrees that during his employment with PML, and for
a period of two years after termination of his employment,  he will not directly
or indirectly solicit for employment any employee of PML.


               9.3  If  Employee   violates  any  of  the  provisions  of  these
subparagraphs, Employer shall be entitled to receive from Employee reimbursement
for any and all damages caused by such breach, as liquidated  damages and not as
a penalty (both Employer and Employee  realizing the difficulty in  establishing
the amount of actual damages incurred by PML as the result of such a breach), an
amount equal to fifty  percent  (50%) of  Employee's  then  current  yearly base
salary if still  employed by PML,  or if no longer  employed  by  Employer,  the
amount of Employee's  yearly base salary at the time of his  termination.  It is
understood  and agreed that this remedy is in addition  to, and not a limitation
on, any injunctive relief for other rights or remedies to which PML is or may be
entitled to under the law.

               9.4 If any  provisions  of  these  subparagraphs  are  held to be
invalid or unenforceable, the remaining provisions shall, nevertheless, continue
to be valid and enforceable as though the invalid or unenforceable parts had not
been included.
<PAGE>
       10 . Termination.

               10.1 Either  Employee or Employer may terminate this Agreement at
any time with or without cause. For purposes of paragraph 10.1 only,  "cause" is
defined as any one or more of the following:

               10.1.1  Dishonesty  that  materially  impairs the interest of PML

               10.1.2  Refusal to follow a lawful  direction of the Board.

               10.1.3  Conviction  of a crime  that is  classified  as  either a
misdemeanor or a felony.

               10.1.4 Personal or professional conduct which injures or tends to
injure the reputation of Employer or otherwise  significantly  adversely affects
the interests of Employer.

               10.1.5 Failure to reach mutually agreed performance targets.

               10.1.6 Deterioration of the financial condition of Employer which
makes it impossible to continue.

               10.1.7  Death of Employee,  other than death caused  primarily by
Employee's performing duties on behalf of Employer.

               10.1.8  Disability  of Employee for a  cumulative  period of more
than  twelve  weeks in any  one-year  period  other than any  disability  caused
primarily by Employee's  performing  duties on behalf of Employer.  "Disability"
means being unable to perform the essential functions of the job with or without
reasonable accommodation.

               10.2  Effect  of  Termination.  Upon  termination  of  Employee's
employment with PML, Employer agrees to pay Employee all salary due and owing to
Employee  as of the  date of  termination,  less  legal  deductions  or  offsets
Employee  may owe to  Employer  for such  items as  salary  advances  or  loans.
Employee   agrees  that  his  signature  on  this  Agreement   constitutes   his
authorization  for all such deductions.  Employee agrees to return to PML all of
Employer's  property of any kind which may be in Employee's  possession.  In the
event of  termination  of this  Agreement,  the  terms  and  provisions  of this
Agreement  shall  also  terminate,  with the  exception  of the  confidentiality
provisions provided in the paragraphs above.

               10.3  Employee's  compliance with the terms and conditions of the
Support  Agreement  dated November 25, 1996 and signed by PML  Microbiologicals,
Inc., Norwest Business Credit, Inc. and Kenneth L. Minton shall not be construed
as a termination  of this  Agreement  ("the Support  Agreement").  The terms and
conditions  of the  Agreement  shall  remain  in full  force and  effect  during
Employee's  compliance  with  the  terms  of the  Support  Agreement.  By way of
example, but not as a limitation,  Employee's employment may still be terminated
according to the terms of the Agreement, and Employee will still be eligible for
any stock option  and/or  bonus,  providing he otherwise  qualifies  pursuant to
terms and conditions contained in the Agreement.

         11 .     Severance.

               11.1 If  termination  is for  "cause"  (as  defined in  paragraph
10.1), no severance will be paid.

               11.2 If  termination  is for  reasons  other than for "cause" (as
defined in Paragraph  10.1) or the  expiration of the contract,  severance  will
equal all base salary payable under the remaining term of the contract  (through
May 31, 2002),  and any bonus  pursuant to Paragraph  5.7. The severance will be
paid on regularly scheduled pay dates or in one lump sum, at Employer's option.
<PAGE>
               11.3 If Employee  quits at any time before the contract  expires,
he will receive no severance.

               11.4 Severance paid pursuant to paragraph 11 will be paid only in
exchange for a mutual release of all claims.

       12 . Family Position.  The terms and conditions of the document  entitled
"Family Position," attached hereto as Exhibit B, are incorporated herein by this
reference.

       13 . Construction of Agreement.

               13.1 Superseding  Agreement.  This Agreement supersedes any prior
Agreements,  written  or  oral,  including  without  limitation  the  Employment
Agreement entered into on April 4, 1996.

               13.2  Essential  Terms  and  Modification  of  Agreement.  It  is
understood and agreed that the terms and conditions  described in this Agreement
constitute  the essential  terms and  conditions of the  employment  arrangement
between Employer and Employee,  all of which have been voluntarily  agreed upon.
Employer  and  Employee  agree  that  there  are no  other  essential  terms  or
conditions of the  employment  relationship  that are not described  within this
Agreement,  and that any change in the  essential  terms and  conditions of this
Agreement will be written down in a supplemental agreement which shall be signed
by both Employer and Employee before it is effective.

               13.3 Severability.  If any term, covenant, condition or provision
of this  Agreement  or the  application  thereof to any  person or  circumstance
shall, at any time, or to any extent,  be determined  invalid or  unenforceable,
the  remaining  provisions  hereof  shall not be  affected  thereby and shall be
deemed valid and fully enforceable to the extent permitted by law.

               13.4  Notices.  Any notice  hereunder  shall be  sufficient if in
writing and  delivered to the party or sent by certified  mail,  return  receipt
requested and addressed as follows:

                           a.       If to Employer:  Ron Torland
                                                     10595 SW Kiowa Street
                                                     Tualatin, OR 97062


                           b.       If to Employee:  Kenneth L. Minton
                                                     2390 Michael Court
                                                     West Linn, OR 97068

Either  party may change the address  herein  specified  by giving to the other.
Notice shall be effective on the day of mailing.

               13.5 Governing Law and Venue. This Agreement is made and shall be
construed and performed  under the laws of the State of Oregon.  In the event of
any dispute between Employer and Employee,  venue shall be in Washington County,
Oregon.

               13.6 Waiver of  Agreement.  The waiver by Employer of a breach of
any provision of this Agreement by Employee shall not operate or be construed as
a waiver by Employer of any subsequent breach by Employee.

               13.7  Captions.  The captions and headings of the  paragraphs  of
this Agreement are for  convenience and reference only and are not to be used to
interpret or define the provisions hereof.

               13.8  Assignment and  Successors.  The rights and  obligations of
Employer under this Agreement  shall inure to the benefit of and be binding upon
the successors and assigns of Employer.  The rights and  obligations of Employee
hereunder are  nonassignable.  Employer may assign its rights and obligations to
any entity in which Employer or a company affiliated to Employer, has a majority
ownership interest.

               13.9 Notice of Intent Not to Renew.  Employee and  Employer  both
agree to provide  the other with no less than 90 days  prior  written  notice of
their intent not to renew the contract and/or to continue  employment beyond the
term of the contract.

         DATED this day of     , 1997.

EMPLOYEE:                                            EMPLOYER:

KENNETH L. MINTON                           PML MICROBIOLOGICALS, INC.
                                            and PML, INC.



                                            By
                                            Its