1 EXHIBIT 21 SUBSIDIARIES OF ARCH CHEMICALS, INC.(1) (as of December 31, 2000) SUBSIDIARY JURISDICTION PERCENTAGE OF DIRECT/ - ---------- WHERE ORGANIZED INDIRECT OWNERSHIP BY --------------- ARCH OF VOTING SECURITIES ------------------------- Arch Acquisition Corp. Delaware 100% Arch Asia Holdings, Ltd. Republic of Mauritius 100% Arch Chemicals B.V. The Netherlands 100% Arch Chemicals California Holdings, Inc. Delaware 100% Arch Chemicals Canada, Inc. Canada 100% Arch Chemicals Far East, Limited Delaware 100% Arch Chemicals GmbH Germany 100% Arch Chemicals Holdings, Inc. Virginia 100% Arch Chemicals (Hong Kong) Limited Hong Kong 100% Arch Chemicals Japan, Inc. Japan 100% Arch Chemicals Limited United Kingdom 100% Arch Chemicals NV Belgium 100% Arch Chemicals S.A. France 100% Arch Chemicals S.R.L. Italy 100% Arch Chemicals Singapore Pte Ltd Singapore 100% Arch Chemicals Specialty Products, Inc. Delaware 100% Arch Chemicals (Suzhou) Co., Ltd. People's Republic of China 100% Arch Chemicals UK Holdings Limited United Kingdom 100% Arch Coatings Italia SpA Italy 100% Arch Color SpA Italy 100% Arch Electronic Chemicals NV Belgium 100% Arch Electronic Chemicals, Inc. Pennsylvania 100% Arch Export Trading Corporation Barbados 100% Arch Kimya A.S.(2) Turkey 98.85% Arch Overseas Finance N.V. Belgium 100% Arch Personal Care Products, L.P. New Jersey 100% Arch Quimica Andina C.A. Venezuela 100% Arch Quimica Brasil Ltda. Brazil 100% Arch Semiconductor Chemicals GmbH Germany 100% Arch Semiconductor Chemicals Limited United Kingdom 100% Arch Semiconductor Chemicals S.A. France 100% Arch Specialty Chemicals, Inc. Delaware 100% Arch Timber Protection AB Sweden 100% Arch Wood Protection Canada Corp. Canada 100% Arch Wood Protection, Inc. Delaware 100% Doe Run Gas Marketing Company Kentucky 100% Doe Run Gas Transmission Company Kentucky 100% FKP, Inc. Delaware 100% Hickson Argentina S.A. Argentina 100% Hickson Chemical Holdings (Pty) Ltd. South Africa 100% Hickson Coatings Far East (Pte) Ltd.(3) Singapore 100% Hickson Coatings France SA France 100% Hickson DanChem Corporation Delaware 100% Hickson Finance, Inc. Delaware 100% Hickson Garantor Nederland BV The Netherlands 100% Hickson Garantor Nederland NV Belgium 100% Hickson Insurance Limited United Kingdom 100% Hickson International Limited United Kingdom 100% Hickson Investments (France) SA France 100% Hickson Investments Espana SL Spain 100% Hickson Investments Limited United Kingdom 100% Hickson Limited United Kingdom 100% Hickson Nederland BV The Netherlands 100% Hickson (USA) Corp. Delaware 100% Hydrochim S.A. France 100% Hydromen Espana, S.L. Spain 100% Inversiones Hickson Chile SA Chile 100% Sulphur Dyes Limited United Kingdom 100% Tecnoselect SL(4) Spain 67% (1) There are omitted from the list the names of certain subsidiaries which, if considered in the aggregate as a single subsidiary, would not constitute a significant subsidiary. (2) Percentage of ownership increased to 100% effective January 30, 2001. (3) Now known as Arch Chemicals Coatings Singapore Pte Ltd (4) Percentage of ownership increased to 100% effective January 3, 2001.