In 2006-07 NICNAS completed to public comment stage previously drafted hazard assessments of 25 phthalate chemicals, together with a compendium summarising toxicological and use information on the 25 chemicals. The compendium highlights data gaps, comments on toxicological and molecular structural similarities and differences between the chemicals and – for chemicals with little data – extrapolates likely toxicological effects based on structurally similar phthalates.