Contaminated lead environments of man: reviewing the lead isotopic evidence in sediments, peat, and soils for the temporal and spatial patterns of atmospheric lead pollution in Sweden

Abstract

Clair Patterson and colleagues demonstrated already four decades ago that the lead cycle was greatly altered on a global scale by humans. Moreover, this change occurred long before the implementation of monitoring programs designed to study lead and other trace metals. Patterson and colleagues also developed stable lead isotope analyses as a tool to differentiate between natural and pollution-derived lead. Since then, stable isotope analyses of sediment, peat, herbaria collections, soils, and forest plants have given us new insights into lead biogeochemical cycling in space and time. Three important conclusions from our studies of lead in the Swedish environment conducted over the past 15 years, which are well supported by extensive results from elsewhere in Europe and in North America, are: (1) lead deposition rates at sites removed from major point sources during the twentieth century were about 1,000 times higher than natural background deposition rates a few thousand years ago (~10 mg Pb m(-2) year(-1) vs. 0.01 mg Pb m(-2) year(-1)), and even today (~1 mg Pb m(-2) year(-1)) are still almost 100 times greater than natural rates. This increase from natural background to maximum fluxes is similar to estimated changes in body burdens of lead from ancient times to the twentieth century. (2) Stable lead isotopes ((206)Pb/(207)Pb ratios shown in this paper) are an effective tool to distinguish anthropogenic lead from the natural lead present in sediments, peat, and soils for both the majority of sites receiving diffuse inputs from long range and regional sources and for sites in close proximity to point sources. In sediments >3,500 years and in the parent soil material of the C-horizon, (206)Pb/(207)Pb ratios are higher, 1.3 to >2.0, whereas pollution sources and surface soils and peat have lower ratios that have been in the range 1.14-1.18. (3) Using stable lead isotopes, we have estimated that in southern Sweden the cumulative anthropogenic burden of atmospherically deposited lead is ~2-5 g Pb m(-2) and ~1 g Pb m(-2) in the "pristine" north. Half of this cumulative total was deposited before industrialization. (4) In the vicinity of the Rönnskär smelter in northern Sweden, a major point source during the twentieth century, there is an isotopic pattern that deviates from the general trends elsewhere, reflecting the particular history of ore usage at Rönnskär, which further demonstrates the chronological record of lead loading recorded in peat and in soil mor horizons.

Comparison of 265 nm Femtosecond and 213 nm Nanosecond Laser Ablation Inductively Coupled Plasma Mass Spectrometry for Pb Isotope Ratio Measurements

“…[1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] The Pb is certainly the most powerful among radiogenic elements available with respect to isotope geochemists, because it has three radiogenic isotopes whose precursors of U and Th are relatively short half-lives and are very different from each other, and the chemistry of Pb is also quite different from that of its precursors. Laser ablation multi-collector inductively coupled plasma mass spectrometry (LA-MC-ICPMS) has already been accepted as a suitable tool for precise isotopic microanalysis in solid samples at scales down to about 5 -100 μm; since the MC-ICPMS can achieve simultaneous multi-isotope measurements by its multi-collector even though the number of detector is limited.…”

The fate of atmospheric metal pollutants in the landscape, Snowy Mountains, south-eastern Australia

“…In Sweden, the Pb burden from all emissions to present stands at 2-5 g/m 2 in the south and 1 g/m 2 in the more remote north (Bindler, 2011). For the Southern Hemisphere, enrichment is less well constrained but is presently lower due to lower volume of industrial emissions.…”

“…Beginning in prehistoric times, human activities have modified the flux of metals to the extent that anthropogenic metals can now be considered ubiquitous in the Earth's environment (Bindler, 2011;Murozumi et al, 1969;Shotyk, 1996a). Patterson et al (1965) demonstrated the scale of their impact when they showed in the 1960s that blood Pb concentrations in the United States of America had reached approximately 100 times natural levels.…”

“…The first significant emissions of anthropogenic metals to the environment occurred as a byproduct early copper smelting (Bindler, 2011). Evidence of associated contamination is found as early as 8000 yrs BP in the sediments of Lake Manganese and Copper Falls Lake on Michigan's Keweenaw Peninsula (Pompeani et al, 2013).…”

“…Currently, the evidence from peat, lake and ice records indicates that Pb is being deposited to western Europe at 100 x the pre-anthropogenic rate (Bindler, 2011). In Sweden, the Pb burden from all emissions to present stands at 2-5 g/m 2 in the south and 1 g/m 2 in the more remote north (Bindler, 2011).…”