R6 PM Bioavailability
Thursday, 17 November 2005: 1:50 PM - 5:30 PM in 324-326

(LEW-1117-833415) Temporal and Spatial Variability of Free Ion Copper in Boston Harbor.

Lewis, Christopher¹, Shine, James¹, Coull, Brent¹, ¹ Harvard School of Public Health, Boston, MA, USA

ABSTRACT- With developing regulatory focus on the use of Total Maximum Daily Load models (TMDLs) and the Biotic Ligand Model (BLM), there is a need to understand the temporal and spatial variability of parameters used as inputs into these models. For example, the free metal ion concentration, a cornerstone of the BLM, may have substantial temporal and spatial variability that must be quantified before a BLM-based water quality criterion can be implemented. A field-based study was conducted to quantify the role of space and time in the variance of free ion Cu concentrations measured in Boston Harbor, using the recently developed field-deployable version of the Gellyfish Sampler, an equilibrium-based sampler that measures free ion concentration. In addition to estimated free ion Cu concentrations, a host of other aquatic chemical parameters were measured, including DOC, POC, Chl-a, total dissolved and particulate Cu, and salinity and temperature. A general linear model with mixed effects, using random spatial and temporal effects was used to quantify the contributions of space and time to the total estimates of the variance. In addition, using regression analyses, aquatic chemical parameters were tested as predictors of free ion concentration.

Key words: free ion, metal, gellyfish sampler, boston harbor