Anatomy of a decision: Potential regulatory outcomes from changes to chemistry protocols in the Canadian Disposal at Sea Program

► We developed a sediment database to examine Canadian dredged material assessment approaches. ► Expansion of the chemical list would likely result in more sediment requiring toxicity assessment. ► The list of analytes has a greater impact on outcomes than specific sediment quality guidelines used. ► A chemical upper action level could focus toxicity testing on sediments of uncertain quality. ► Further work on the impacts of changes to both chemical and toxicity approaches is indicated.