DDT in indoor residual spraying: human health aspects

Overview

Two World Health Organization (WHO) expert consultations held in 2009 resulted in a dichlorodiphenyltrichloroethane (DDT) hazard assessment and an exposure assessment for the use of DDT in indoor residual spraying (IRS).

These two assessments, agreed by the experts present at those consultations and presented in Part B of this publication, provided a basis for the WHO expert consultation on DDT risk characterization, which was conducted for the purpose of assessing human health risks arising from the use of DDT in IRS. The WHO expert consultation on DDT hazard assessment requested that additional modelling be conducted following that meeting, as part of the hazard characterization step of the hazard assessment, to develop benchmark doses (BMDs) for a number of studies.

These BMDs were to be made available for the risk characterization expert consultation to use as appropriate. The additional dose–response modelling was prepared by the Secretariat and reviewed by an external expert. In addition, the Secretariat provided relevant dose metrics, expressed as micrograms per gram lipid, to facilitate the comparison between experimental animal and human data.

Details of the methods used to convert the data to a common metric are presented in section 11.2.1 of Part B, along with details of the dose–response modelling that was conducted to derive BMDs for a 10% response (BMD10 values) and lower 95% confidence limits on the BMDs for a 10% response (BMDL10 values).