Affiliations with the Letter U
- U.S. Anti Doping Agency -- United States
- U.S. Army Edgewood Research -- United States
- U.S. Department of Agriculture -- United States
- U.S. Department of Energy -- United States
- U.S. Department of State -- United States
- U.S. Environmental Protection Agency -- United States
- U.S. Food and Drug Administration -- United States
- U.S. Geological Survey -- United States
- U.S. National Cancer Institute -- United States
- Ube Industries, Ltd. -- Japan
- UFZ Center for Environmental Research -- Germany
- UFZ Umweltforschungszentrum Leipzig-Halle GmbH -- Germany
- Uludag Üniversitesi -- Turkey
- Umeå Universitet -- Sweden
- Umweltbundesamt -- Germany
- UNDA, Sydney Medical School -- Germany
- UNESCO -- France
- Unilever -- Hungary
- Unilever -- United Kingdom
- Union Chimique Belge, SA -- Belgium
- Union des Industries Chimiques (UIC) -- France
- Uniqema International -- Netherlands
- Uniqema International -- United States
- United Medix Laboratories -- Finland
- United Nationals Environmental Programme (UNEP) -- Switzerland
- Unitika, Ltd. -- Japan
- Univerity of California at Davis -- United States
- Universidad Autònoma de Barcelona -- Spain
- Universidad Autónoma de Mexico -- Mexico
- Universidad Autónoma de Nuevo León -- Mexico