Mercury and Dissolved Organic Matter
How does dissolved organic matter influence methylmercury production and bioavailability in the ocean?
Methylmercury is produced by bacteria, sulfate and iron reducers are the best known for methylating inorganic mercury, although the exact mechanism (s) is still being actively investigated. Because methylation is a bacterially mediated process, dissolved organic matter is an important actor, but its role is unclear. For this project started during my PhD, I used using a combination of field, experimental and statistical modeling to answer the question:
Paper is now in
I collected water samples from multiple locations in the North Atlantic Ocean and seasonally in Long Island Sound. Dissolved organic matter was extracted and characterized. I also measured mercury species and a slew of ancillary parameters. I did titration experiments using the extracted organic matter and mercury. My co-author Dr. Udonna Ndu used the organic matter to study how mercury enters the bacterial cell. His work has been published in Applied Environmental Microbiology.