Exhibit 99.1

NEWS RELEASE
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                                                                  [ARCH LOGO]


ARCH CHEMICALS, INC.
501 Merritt 7
P.O. Box 5204
Norwalk, CT 06856



                             Investor Contact: MARK E. FAFORD (203) 229-2654

                                Press Contact: DALE N. WALTER (203) 229-3033



            ARCH WOOD PROTECTION, INC. ANNOUNCES THAT FEDERAL COURT
           REJECTS CLASS ACTION STATUS FOR CCA-TREATED WOOD LAWSUIT


SMYRNA, Georgia, April 2, 2004 -- The United States District Court in Western
Louisiana has denied class action status to a lawsuit challenging the safety
of wood treated with Chromated Copper Arsenate (CCA).

The ruling in Ardoin vs. Stine Lumber Co., et al. was made after the
plaintiffs took the unusual step of attempting to dismiss their own lawsuit.
The court denied the plaintiffs' attempted dismissal and ordered a hearing on
the class issue. In a strongly worded ruling for the defense, District Court
Judge Patricia Minaldi rejected all of the plaintiffs' arguments for class
certification.

This is the third time a court has rejected class certification of a case
challenging the safety of CCA-treated wood. No court has ever granted class
action status to such a case.

Jim Hale, executive director of the Wood Preservative Science Council,
commented, "This ruling is a major vindication for the treated wood industry."

Headquartered in Smyrna, GA, Arch Wood Protection, Inc. manufactures various
preservatives and additives to enhance the properties of wood, and provides
engineering, environmental,





technical and marketing services to its treaters and other customers. With
manufacturing operations in North America and Europe, joint ventures in South
America and Australasia, and laboratories in Georgia, England and New Zealand,
Arch Wood Protection has developed unsurpassed expertise in wood preservation
technology. For more information about Arch Wood Protection, go to
www.naturalselect.com and www.wolmanizedwood.com.

Arch Wood Protection, Inc. is a subsidiary of Arch Chemicals, Inc. (NYSE:
ARJ), a global specialty chemicals company with $1 billion in annual sales.


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Except for historical information contained herein, the information set forth
in this communication contains forward-looking statements that are based on
management's beliefs, certain assumptions made by management and management's
current expectations, estimates and projections about the markets and economy
in which Arch and its various businesses operate. Words such as "anticipates,"
"believes," "estimates," "expects," "forecasts," "opines," "plans,"
"predicts," "projects," "should," "targets," "will," and variations of such
words and similar expressions are intended to identify such forward-looking
statements. These statements are not guarantees of future performance and
involve certain risks, uncertainties and assumptions ("Future Factors"), which
are difficult to predict. Therefore, actual outcomes and results may differ
materially from what is expected or forecasted in such forward-looking
statements. The Company undertakes no obligation to update publicly any
forward-looking statements, whether as a result of future events, new
information or otherwise. Future Factors which could cause actual results to
differ materially from those discussed include but are not limited to: general
economic and business and market conditions; lack of economic recovery in 2004
in the U.S.; lack of moderate growth or recession in European economies;
increases in interest rates; economic conditions in Asia; worsening economic
and political conditions in Venezuela; strengthening of the U.S. dollar
against foreign currencies; customer acceptance of new products; efficacy of
new technology; changes in U.S. laws and regulations; increased competitive
and/or customer pressure; the Company's ability to maintain chemical price
increases; higher-than-expected raw material costs for certain chemical
product lines; increased foreign competition in the calcium hypochlorite
markets; lack of continued recovery in the semiconductor industry;



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unfavorable court, arbitration or jury decisions; the supply/demand balance
for the Company's products, including the impact of excess industry capacity;
failure to achieve targeted cost-reduction programs; unsuccessful entry into
new markets for electronic chemicals; capital expenditures in excess of those
scheduled; environmental costs in excess of those projected; the occurrence of
unexpected manufacturing interruptions/outages at customer or company plants;
reduction in expected government contract orders and/or the failure to renew
or extend the U.S. government contract for hydrazine propellants; unfavorable
weather conditions for swimming pool use; inability to expand sales in the
professional pool dealer market; and gains or losses on derivative
instruments.



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