Modeling Monomethylmercury and Tributyltin Speciation with EPA’s Geochemical Speciation Model MINTEQA2
Monomethylmercury (MMHg) is the compound responsible for the majority of fish consumption advisories in forty eight states in the United States of America. These widespread low level (but toxicologically significant) ecological exposures to MMHg result from microbial methylation of atmospherically deposited inorganic mercury in our national waterbodies. Tributyltin (TBT) is an industrially synthesized antifoulant compound that was historically added to paints applied to the hulls of ships, boats and other watercraft. There is an extensive technical literature on the adverse effects associated with low level ecological exposures to this compound. Although the use of TBT has been restricted in recent years, there exists a significant reservoir of TBT in the sediments underlying our nation’s boatyards and marinas.