This publication presents an updated human health risk assessment for the insecticide DDT, focusing on DDT use in indoor residual spraying for disease vector control. The publication contains an updated hazard assessment for DDT, including new scientific information published since the previous WHO assessment in 2001. There is also a human exposure assessment for DDT, which places exposure arising from indoor residual spraying in the context of residues of DDT and its metabolites in people exposed via previous agricultural and public health use of DDT. The risk assessment is completed by the report of a WHO expert consultation which was convened to prepare the risk characterization, based on the above hazard and exposure assessments.