Comparison of partial extraction reagents for assessing potential bioavailability of heavy metals in sediments

• Partial extraction reagents for bioavailable heavy metals in sediments were compared.
• Partial extractable metal concentrations in the MESS-3 CRM were determined.
• 1 M extracting solutions were shown to be more efficient than chelating agents.
• 1 M HNO3 provided the best extraction efficiencies.

Assessment of heavy metal bioavailability in sediments is complex because of the number of partial extraction methods available for the assessment and the general lack of certified reference materials. This study evaluates five different extraction methodologies to ascertain the relative strengths and weaknesses of each method. The results are then compared to previously published work to ascertain the most effective partial extraction technique, which was established to dilute (0.75–1 M) nitric acid solutions. These results imply that single reagent; weak acid extractions provide a better assessment of potentially bioavailable metals than the chelating agents used in sequential extraction methods.