PARENT SESSION
WA1 - Bioavailability
Chair: Griscom, Sara1, 1 48 Main Street, Southborough, MA
8:00 AM to 12:00 PM - Wednesday, 20 November 2002
Room Ballroom G-I
(491) Bioaccumulation of Platinum Group Metals (PGMs) in Earthworms (Lumbricus terrestris).
Crocco, Michael1, Porzio, Vin2, Newkirk, Catherine3, Gagnon, Zofia*,2, Fitzgerald, Neil4, Conetta, Joseph5, 1 Department of Biology, Marist College, Poughkeepsie, New York2 Department of Environmental Sciences, Marist College, Poughkeepsie, New York3 Departmental of Medical Technology, Marist College, Poughkeepsie, New York4 Department of Chemistry and Physics, Marist College, Poughkeepsie, New York5 Department of Comparative Medicine, New York Medical College, Valhalla, New York
ABSTRACT- Deposition of platinum group metals (PGMs); in particular platinum, palladium and rhodium; from automobile catalytic converters has led to an increase in concentrations of these elements in the environment. There is growing concern that PGMs are toxic to living organisms, yet little research has been done to ascertain health risks. This experiment is part of a series of experiments to assay the bioaccumulation of PGMs in living organisms. Chemical analysis, using atomic absorption spectrometry, demonstrates accumulation of PGMs in plant material at all PGM media levels applied to plant growth. In this experiment, earthworms were exposed, for a period of fifteen days, to different concentrations of platinum and of platinum in combination with palladium and rhodium (0.01, 0.1 and 1.0 ppm concentrations, respectively). Metals were obtained in concentrations of 1000 mg/L in a matrix of 10 percent HCl, diluted with distilled water and added to a formulated mixture of organic potting soil, peat moss and water. Six worms were added to each metal/soil mixture (including a water control and a 10 percent HCl control) in a polyethylene container with air holes. The worms, in different mixtures, were set up in triplicate. Worms from each group were purged in distilled water on day 5, day 10, and day 15, respectively. They were desiccated, weighed and tissue was prepared for atomic absorption analysis of metals by digestion using 7N nitric acid. The Varian SpectrAA 20 Plus Graphite Furnace Atomic Absorption Spectrometer will be used for the final determination of metal concentration in tissue samples. The experiment will determine whether there is accumulation of metals over time and whether platinum is absorbed at a different rate when exposed singly or in combination with palladium and rhodium. Through a series of experiments; exposing plants, earthworms and rats to PGMs; the bioaccumulation and toxicity of these heavy metals can be better understood.
Key words: bioaccumulation, platinum, rhodium and palladium, DNA damage, earthworms