HR: 1400h
AN: B13B-01    [Abstracts]
TI: Metal-Microbial Interactions in Toronto Sunnyside Beach: Impact on Water Quality and Public Health
AU: * Plach, J M
EM: plachj@mcmaster.ca
AF: McMaster University, 1280 Main Street West, Hamilton, ON L8S4L8, Canada
AU: Elliott, A
EM: elliotav@mcmaster.ca
AF: McMaster University, 1280 Main Street West, Hamilton, ON L8S4L8, Canada
AU: Warren, L A
EM: warrenl@mcmaster.ca
AF: McMaster University, 1280 Main Street West, Hamilton, ON L8S4L8, Canada
AB: Assessing recreational water quality requires a fundamental understanding of metal-microbial interactions and the key biogeochemical processes occurring in urban public beaches. Metals play an important role in the distribution and virulence (e.g. resistance) of microorganisms in water systems. In turn, microorganisms have a significant influence on metal cycling, thus affecting metal mobility, bioavailability and toxicity in the aquatic environment. Bacteria adhere to floc, small suspended mineral-bacterial aggregates, in aquatic systems resulting in high-density floc-associated bacterial biofilm communities. These nanoparticulate bacterial microhabitats are important environmental sinks for metals and potential reservoirs for antibiotic resistant and pathogenic bacteria. The objectives of this study are to identify and quantify (1) metal distributions among suspended floc, bed sediment and water-column aqueous compartments (2) important biogeochemical processes influencing metal cycling and (3) linkages between floc metals and the occurrence of floc associated antibiotic resistant bacteria and pathogens across a series of variably contaminated aquatic systems. Results of this project will provide new diagnostic indicators of pathogens in recreational water systems and aid in the development of public health policies to improve water quality and reduce water borne infectious disease. Here, results will be presented assessing the metal and microbial community dynamics in samples collected from Toronto's Sunnyside Beach (May 13 and August 20), an urban public beach on Lake Ontario. Water column, floc and bed sediments near and offshore were analyzed for physico-chemical characteristics and metal concentrations. Floc were imaged using DAPI and FISH to assess microbial community structure. Results to date, characterizing the linkages amongst bacteria, metal contaminant concentrations and sediment partitioning and system physico-chemical conditions will be discussed.
DE: 0461 Metals
DE: 0463 Microbe/mineral interactions
DE: 0496 Water quality
SC: Biogeosciences [B]
MN: 2009 Joint Assembly