No abstract

The fate and transport of Detroit River derived sediment-bound pollutants in Lake Erie were investigated by the electron impact gas chromatographic mass spectrometric analysis of 2,4-di-tert-pentylphenol (24DP), an unusual sediment-bound pollutant originating from a single point source on the Trenton Channel of the Detroit River. The 24DP depositional histories were determined in 25 dated sediment cores taken throughout Lake Erie; 24DP occurred in sediments throughout the lake from the mid-1930s until the cores were collected in the late 1980s, with maximum deposition occurring in 1968 ± 2 years in all three basins of the lake. The average depositional fluxes of 24DP at the 25 sampling sites were determined and used in a three-compartment model of Lake Erie's sedimentation basins. Mass balance was applied to determine pollutant accumulation rates in each basin and interbasin transport rates. About 73% of Detroit River derived, sediment-bound pollutants accumulate in the relatively small western basin of Lake Erie, ~20% accumulate in the central basin, and ~5% accumulate in the deep eastern basin. The region of the lake most severely affected by the discharge of hydrophobic pollutants from the Detroit River is the western basin within 20-30 km of the mouth of the river.

Whole carp from the Detroit River were analyzed by gas chromatographic mass spectrometry. Seven tertiary alkyl phenols (tert-pentylphenols, tert-butyl-tert-pentylphenols, a di-tert-pentylphenol and a tri-tert-pentylphenol) and eight chlorinated derivatives of these compounds were identified from their mass spectra and confirmed with synthesized authentic standards. 2,4-Di-tert-pentylphenol was the most abundant of these compounds; in one fish sample, its concentration was about 140 ppm. The same alkyl phenols were also found in technical-grade 2,4-di-tert-pentylphenol, which is manufactured at a chemical plant located near the Detroit River. Comparison of the alkyl phenol levels in carp with those in nearby sediments showed that many of these compounds are taken up by carp and that carp can be used to roughly track local sediment contamination.

No abstract

The characteristics of the data sets used in this report are described, and results are interpreted with respect to factors that affect observed pesticide concentrations.