『Abstract
This investigation revealed the presence of traffic-derived metals
within road, stream and estuarine sediments collected from a coastal
catchment, northern Australia. Studied road sediments displayed
variable total metal concentrations (median Cd, Cu, Pb, Pd, Pt,
Ni and Zn values: 0.19, 42.6, 67.5, 0.064, 0.104, 36.7 and 698
mg/kg, respectively). The distinctly elevated Zn values are due
to abundant tyre rubber shreds (as verified by SEM-EDS and correlation
analysis). By comparison to the road sediments, background stream
sediments taken upstream from roads have relatively low median
Pb, Pd, Pt and Zn concentrations (7.3 mg/kg Pb, 0.01 mg/kg Pd,
0.012 mg/kg Pt, 62 mg/kg Zn). Stream and estuarine sediment samples
collected below roads have median values of 21.8 mg/kg Pb, 0.014
mg/kg Pd, 0.021 mg/kg Pt and 71 mg/kg Zn, and exhibit 207Pb/206Pb
and 208Pb/206Pb ratios that appear on a
mixing line between the isotopically distinct background stream
sediments and the road sediments. thus, mobilisation of dusts
and sediments from road surfaces has resulted in relatively elevated
Pb, Pd, Pt and Zn concentrations and non-radiogenic Pb isotope
ratios in local coastal stream and estuarine sediments. the investigation
demonstrates that traffic-derived metals enter coastal stream
and estuary sediments at the fringe of the Great Barrier Reef
lagoon.
Keywords: Traffic pollution; Road sediments; Stream sediments;
Metals; Pb isotopes; Australia』
Introduction
Avondale Creek catchment
Physiography and climate
Geology, soils and landuse
Roads
Materials and methods
Sampling and sample processing
Analytical methods
Results
Road sediments
Stream and estuarine sediments
Discussion
Road sediments as sources of trace metal contaminants
Dispersion into stream sediments
Conclusions
Acknowledgments
References