AMERICAN PACIFIC CORPORATION ANNOUNCES
                       AMMONIUM PERCHLORATE CHANGE ORDER

LAS  VEGAS,  NEVADA,  March  22,  2000  /  PR  Newswire  / --  American  Pacific
Corporation  (NASDAQ  National  Market:  APFC)  announced  that is has  received
notification from Thiokol Propulsion (a division of Cordant Technologies,  Inc.)
of a change in the current  purchase order for ammonium  perchlorate  (AP) which
will result in a decrease  of  approximately  3.23  million  pounds  (from 10.48
million   pounds)  and  a   consequent   estimated   reduction  in  revenues  of
approximately $4.0 million in the current fiscal year ending September 30, 2000.
Under the change  order,  the Company will be required to make a claim for price
adjustment within 30 days.  Subject to the outcome of the price adjustment claim
process,  the purchase order  modification may have a material adverse effect on
the Company's fiscal year 2000 operating results.

The primary  business of American  Pacific  Corporation  is the  manufacture  of
specialty  chemicals.  The  Company  is the sole  producer  in North  America of
ammonium perchlorate,  or AP, which is the principal chemical component of solid
propellants  used in rocket  and  booster  motors by NASA,  the  military  and a
growing number of commercial  launch  vehicles.  American  Pacific  manufactures
Halotron(tm), which replaces Halon as a fire suppressant in applications ranging
from  fire  extinguishers  to  airport   firefighting   vehicles.   The  Company
manufactures  these chemicals in facilities in Utah,  where it also makes sodium
azide, a primary chemical  component of certain  automotive airbag systems.  Its
other  lines of business  include the  production  of  environmental  protection
equipment, and the development of real estate near Las Vegas, Nevada.


Forward Looking Statements


Except for the historical  information  contained herein,  this News Release may
contain Forward Looking  Statements that are subject to risks and uncertainties,
including  potential  declining demand and/or downward pricing pressures for the
Company's  products,  governmental budget constraints and/or decreases affecting
the U.S. Department of Defense or NASA which would cause a continued decrease in
demand for AP,  technological  advances or new  competitive  products  causing a
reduction or elimination of demand for the Company's products,  as well as other
risks  detailed from time to time in the  Company's  SEC reports,  including the
most recent Form 10-K and 10-Q Reports.