Related Experiment Video
Updated: May 16, 2026

An Anaerobic Biosensor Assay for the Detection of Mercury and Cadmium
Published on: December 17, 2018
Methylmercury production in estuarine sediments: role of organic matter
Amina T Schartup1, Robert P Mason, Prentiss H Balcom
1Department of Marine Sciences, University of Connecticut, Groton, Connecticut 06340, USA. schartup@hsph.harvard.edu
Abstract:
Methylmercury (MeHg) affects wildlife and human health mainly through marine fish consumption. In marine systems, MeHg is formed from inorganic mercury (Hg(II)) species primarily in sediments, then accumulates and biomagnifies in the food web. Most of the fish consumed in the United States are from estuarine and marine systems, highlighting the importance of understanding MeHg formation in these productive regions. Sediment organic matter has been shown to limit mercury methylation in estuarine ecosystems, as a result it is often described as the primary control over MeHg production. In this paper, we explore the role of organic matter by looking at the effects of its changing sediment concentrations on the methylation rates across multiple estuaries. We measured sedimentary MeHg production at eleven estuarine sites that were selected for their contrasting biogeochemical characteristics, mercury (Hg) content, and location in the Northeastern U.S. (ME, NH, CT, NY, and NJ). Sedimentary total Hg concentrations ranged across 5 orders of magnitude, increasing in concentration from the pristine, sandy sediments of Wells (ME), to industrially contaminated areas such as Portsmouth (NH) and Hackensack (NJ). We find that methylation rates are the highest at locations with high Hg content (relative to carbon), and that organic matter does not hinder mercury methylation in estuaries.
Related Concept Videos
Marine Microbial Ecology
Freshwater Microbial Ecology
Microbes and Methanogenesis
Deep Sea Microbial Ecology
Microbial Bioremediation of Hydrocarbons
Microbes and the Sulfur Cycle

