Hot off the press! A review and critical assessment of sedimentary metal indices used in determining the magnitude of anthropogenic change in coastal environments

Please join me in congratulating GRG collaborator Associate Professor Gavin Birch on the publication of his new paper in the journal Science of The Total Environment.

Birch, G. F. (2022). A review and critical assessment of sedimentary metal indices used in determining the magnitude of anthropogenic change in coastal environments. Science of The Total Environment, 158129.

Highlights

• First critical evaluation of frequently used sedimentary metal indices
• Examination of inconsistent results produced by different index formulations
• Extraordinary diversity of values and materials being applied to indices
• Mean Enrichment Quotient provided best measurement of enrichment
• Enrichment Factor recommended for total sediment chemical data
• Classification schemes failed to modify inconsistent evaluations

This study examined the application of frequently used sedimentary metal indices and their ability to accurately assess the magnitude of anthropogenic change (contamination) in coastal environments. The multiple indices commonly used in individual investigations should produce a consistent assessment of environmental condition because they use the same suite of contaminants, however they almost never do. The investigation compared these indices to specially prepared sediment metal data produced over three decades at Sydney University and determined that none of the indices produced consistent results. These indices, which have been used for decades in thousands of studies, have evolved over this time, a period during which the science has changed rendering most indices no longer ‘fit for purpose’. The study recommends methodologies that will provide more accurate and more consistent assessment of environmental condition.

The figure below shows the range in enrichment assessment results for the eight indices for the twelve very different east coast Australian estuaries examined compared to acceptable values

Cheers

Ratneel

#MarineScienceSydneyUni