A sanitizing formulation comprising a solution of an acidic polymer and an anionic surfactant in a liquid vehicle. Suitable acidic polymers are those which include adjacent -[-CR1.COOH-]- units where R1 is defined in their structure, for example polymers based on maleic acid moieties which typically include -[-CH.COOH-CH.COOH-]- units, such as known Gantrez(TM) polymers. A suitable anionic surfact is sodium lauryl sulphate.