The dataset captures the temporal and spatial variability of dilution factors (DFs) around the world using geographically referenced data sets at 0.5 degree resolution and includes long term annual and monthly DFs grids. The dilution factor (DF) dataset is composed of 13 rasters: 1 annual and 12 monthly. DFs are a critical component in estimating concentrations of 'down-the-drain' chemicals which enter freshwaters following consumer use via the domestic waste water stream (e.g., pharmaceuticals, household cleaning...