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                                                                    Exhibit 99.1

                  ACETO CORPORATION ANNOUNCES EARNINGS GUIDANCE
                SUBSTANTIALLY HIGHER THAN PRIOR YEAR'S EARNINGS


LAKE SUCCESS, NEW YORK, DECEMBER 5, 2002 - - ACETO CORPORATION (NASDAQ: ACET), a
global distributor of pharmaceuticals and specialty chemicals, announced today
during the webcast of its business presentation during its annual shareholders
meeting that it expects earnings for its fiscal year ending June 30, 2003 to be
in excess of $1.11 per diluted share, before giving effect to any non-cash
goodwill impairment charges, which represents an increase of $0.36 per diluted
share and a 48% increase in earnings over the previous year. This marks the
first time that the Company has provided earnings guidance.

During today's presentation, Leonard S. Schwartz, the Company's Chairman, Chief
Executive Officer and President, stated that, "We expect earnings for our
quarter ending December 31, 2002 to be in excess of $0.26 per diluted share,
before any non-cash goodwill impairment charges relating to our sanitary supply
business. This represents an increase of $0.07 in earnings per diluted share, or
a 37% increase over the same period last year. While it is difficult to forecast
the timing of the introduction of new products, we expect that our earnings for
the quarters ending March 31, 2003 and June 30, 2003 to contribute $0.25 per
diluted share per quarter without any contribution from new product
introductions".

In accordance with the adoption of Statement of Financial Accounting Standards
No. 142, the Company may take a non-cash goodwill impairment charge related to
its sanitary supply business in the quarter ended December 31, 2002. The precise
amount of the charge, if any, is not yet known. If taken, the charge could
materially effect the above guidance and would be recorded as a cumulative
effect of a change in accounting principle in the Company's statement of
operations.

An audio replay of the presentation made earlier today by Mr. Schwartz will be
available through December 19, 2002 by dialing 1-800-945-7497. An archived copy
of the audio webcast will be available by clicking the link found in the article
entitled "Webcast of Aceto's Business Presentation" found in the news portion of
Aceto's website, WWW.ACETO.COM.

This news release contains forward-looking statements within the meaning of
Section 27A of the Securities Act of 1933, as amended, and Section 21E of the
Securities Exchange Act of 1934, as amended. The forward-looking statements are
based on current expectations, estimates and projections made by management. The
Company intends for the forward-looking statements to be covered by the
safe-harbor provisions for forward-looking statements. Words such as
"anticipates," "expects," "intends," "plans," "believes,"

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"seeks," "estimates," or variations of such words are intended to identify such
forward-looking statements. All forward-looking statements in this news release
are made as of the date hereof, and the Company assumes no obligation to update
these forward-looking statements whether as a result of new information, future
events or otherwise. The forward-looking statements are subject to risks and
uncertainties that could cause actual results to differ materially from those
set forth or implied by any forward-looking statements. These uncertainties
include, but are not limited to, economic and political conditions in the United
States and abroad, as well as other risks detailed in the Company's SEC reports,
including the Company's Form 10-K and other filings. Copies of these filings are
available through the SEC's electronic data gathering analysis and retrieval
system (EDGAR) at HTTP://WWW.SEC.GOV.

ABOUT ACETO

Aceto Corporation, which was incorporated in 1947, is a global leader in the
distribution and marketing of pharmaceutical and specialty chemicals used
principally in the agricultural, color, pharmaceutical, surface coating/ink and
general chemical industries. With offices in over nine countries, Aceto
Corporation distributes over 1,000 chemicals in these and other fields.

For more information, please call Chairman Leonard S. Schwartz at 516-627-6000.