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Exhibit 21

SUBSIDIARIES OF CHEMTURA CORPORATION as of December 31, 2012

	Owned Directly or Indirectly by Chemtura Corporation		State or Country of Organization
Anderol B.V.		100.0	The Netherlands
Anderol Italia S.r.l.		51.0	Italy
Antimony Products (Proprietary) Ltd.		75.0	South Africa
Aqua Clear Industries, LLC		100.0	New York
ASEPSIS Inc.		100.0	Canada
ASEPSIS, Inc.		100.0	Georgia
ASIA Stabilizers Co., Ltd.		65.0	Korea
Assured Insurance Company		100.0	Vermont
Baxenden Chemicals Limited		100.0	United Kingdom
BAYROL Deutschland GmbH		100.0	Germany
BAYROL France S.A.S.		100.0	France
BAYROL Iberica S.A.		100.0	Spain
BioLab Australia Pty. Ltd.		100.0	Australia
BioLab U.K. Limited		100.0	United Kingdom
Bio-Lab Canada Inc.		100.0	Canada
Bio-Lab, Inc.		100.0	Delaware
BLSA Industries (Proprietary) Limited		100.0	South Africa
Certis Europe B.V.		15.0	The Netherlands
Chemol Reszvenytarsasag International		78.3	Hungary
Chemtura (China) Holding Company Limited		100.0	China-PRC
Chemtura (HK) Holding Co. Limited		100.0	China-Hong Kong
Chemtura (PTY) Limited		100.0	South Africa
Chemtura (Thailand) Limited		100.0	Thailand
Chemtura Advanced Materials (Nantong) Co., Ltd.		100.0	China-PRC
Chemtura Australia Pty. Ltd.		100.0	Australia
Chemtura Belgium N.V.		100.0	Belgium
Chemtura Canada Co./Cie		100.0	Canada
Chemtura Chemicals (Nanjing) Co., Ltd.		100.0	China-PRC
Chemtura Chemicals India Private Limited		100.0	India
Chemtura Colombia Ltda.		100.0	Colombia
Chemtura Corporation Mexico, S. de R.L. de C.V.		100.0	Mexico
Chemtura Europe d.o.o.		100.0	Slovenia
Chemtura Europe GmbH		100.0	Switzerland
Chemtura Europe Limited		100.0	United Kingdom
Chemtura France SAS		100.0	France
Chemtura Holding Company, Inc.		100.0	Delaware
Chemtura Holdings GmbH		100.0	Germany
Chemtura Hong Kong Limited		100.0	China-Hong Kong
Chemtura Industria Quimica do Brasil Limitada		100.0	Brazil
Chemtura Italy S.r.l.		100.0	Italy
Chemtura Japan Limited		100.0	Japan
Chemtura Korea Inc.		100.0	Korea
Chemtura LLC		100.0	Russia
Chemtura Management GmbH		100.0	Germany
Chemtura Manufacturing Germany GmbH		100.0	Germany
Chemtura Manufacturing Italy S.r.I.		100.0	Italy
Chemtura Manufacturing UK Limited		100.0	United Kingdom

	Owned Directly or Indirectly by Chemtura Corporation		State or Country of Organization
Chemtura Netherlands B.V.		100.0	The Netherlands
Chemtura New Zealand Limited		100.0	New Zealand
Chemtura Organometallics GmbH		100.0	Germany
Chemtura Quimica Argentina S.A.C.I.		100.0	Argentina
Chemtura Sales Europe B.V.		100.0	The Netherlands
Chemtura Sales France SAS		100.0	France
Chemtura Sales Germany GmbH		100.0	Germany
Chemtura Sales Mexico, S. de R.L. de C.V.		100.0	Mexico
Chemtura Sales UK Limited		100.0	United Kingdom
Chemtura Shanghai Co., Ltd.		100.0	China-PRC
Chemtura Singapore Pte. Ltd.		100.0	Singapore
Chemtura Specialties Ecuador S.A.		100.0	Ecuador
Chemtura Specialties India Private Limited		100.0	India
Chemtura Taiwan Limited		100.0	Taiwan
Chemtura Technology B.V.		100.0	The Netherlands
Chemtura UK Limited		100.0	United Kingdom
Chemtura Ukraine LLC		100.0	Ukraine
Chemtura Vermögensverwaltungs GmbH & Co. KG		100.0	Germany
Chemtura Verwaltungs GmbH		50.0	Germany
Crompton (Uniroyal Chemical) Registrations Limited		100.0	United Kingdom
Crompton Chemicals B.V.		100.0	The Netherlands
Crompton Colors Incorporated		100.0	Delaware
Crompton Financial Holdings		100.0	Ireland
Crompton Holdings B.V.		100.0	The Netherlands
Crompton Investments S.A.S.		100.0	France
Crompton Ireland Investment Company Limited		100.0	Ireland
Crompton Kazakhstan LLP		100.0	Kazakhstan
Crompton LLC		100.0	Delaware
Crompton S.A.		100.0	Switzerland
Crompton Servicios S.A. de C.V.		100.0	Mexico
Crompton Specialties GmbH		100.0	Germany
Crompton Specialties Limited		92.0	Thailand
Crompton, Inc.		100.0	Philippines
DayStar Materials L.L.C.		50.0	Korea
DiaKhem Technologies, LLC		30.0	Michigan
GL Development, Ltd.		100.0	British West Indies
GLCC Laurel de Mexico, S.A. de C.V.		100.0	Mexico
GLCC Laurel, LLC		100.0	Delaware
GLCC Mexico Holdings, Inc.		100.0	Delaware
Great Lakes Chemical (Far East) Limited		100.0	Hong Kong
Great Lakes Chemical (Netherlands) B.V.		100.0	The Netherlands
Great Lakes Chemical Corporation		100.0	Delaware
Great Lakes Chemical Konstanz GmbH		100.0	Germany
Great Lakes Europe Unlimited		100.0	United Kingdom
Great Lakes Holding (Europe) A.G.		100.0	Switzerland
Great Lakes Holding S.A.S.		100.0	France
Great Lakes Vermögensverwaltungs GmbH & Co. KG		100.0	Germany
Gulf Stabilizers Industries Sales FZCO		52.0	Dubai
Gulf Stabilizers Industries, Ltd.		49.0	Saudi Arabia
HomeCare Labs, Inc.		100.0	Delaware

	Owned Directly or Indirectly by Chemtura Corporation		State or Country of Organization
Hydrotech Chemical Corporation		100.0	Canada
Hydrotech Chemical Corporation Pty. Ltd.		100.0	Australia
INTERBAYROL, A.G.		100.0	Switzerland
ISEM S.r.l.		50.0	Italy
Knight Investments B.V.		100.0	The Netherlands
MPC S.A.R.L.		100.0	France
Naugatuck Treatment Company		100.0	Connecticut
Poolbrite (SA) (Pty) Ltd		100.0	South Africa
Recreational Water Products Inc.		100.0	Canada
Recreational Water Products, Inc.		100.0	Delaware
Rubicon LLC		50.0	Utah
Unimers India Limited		1.62	India
Uniroyal Chemical S.A.		100.0	Spain
Uniroyal Chemical S.A.R.L.		100.0	Switzerland
Uniroyal Chemical Taiwan Limited		100.0	Taiwan
Vestaron Corporation		0.54	Delaware

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Exhibit 21

SUBSIDIARIES OF CHEMTURA CORPORATION as of December 31, 2012