Elemental bromine serves as oxidant for the identification of propylthiouracil, 2-thiouracil and sulphur according to PH. EUR. 2002. Phenol is identified according to PH. EUR. 2002 with bromine water as the sparingly water-soluble 2,4,4,6-tetrabromo-2,5-cyclohexadiene-1-one. These tests can be performed better using 1,3-dibromo-5,5-dimethylhydantoin (DBH).