کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1739149 | 1016835 | 2008 | 6 صفحه PDF | دانلود رایگان |
Concentrations of fertilizer industry-derived P (up to 3.4%), Ca (up to 6.1%), 226Ra (up to 744 Bq kg−1) and 210Pb (up to 1317 Bq kg−1) at least one order of magnitude above natural levels were recorded in a sediment core from Morrão River estuary (SE Brazil). Unsupported 210Pb (=total 210Pb − 226Ra) activities unexplained by atmospheric fallout and deviations from the radionuclides secular equilibrium also indicated strong anomalies. Anomalous constituents were positively correlated with each other and negatively correlated with clay mineral-bearing elements. These negative correlations were explained by a depletion of natural sediment constituents due to a dilution caused by elevated inputs of steel industry-derived elements (mainly by Fe levels up to 24%). Absolute data and normalizations by a proxy for clays (Al) and anthropogenic Fe evidenced variabilities in the quality of coastal and land-derived sediment inputs, mainly due to changes in the relative contributions from industrial sources.
Journal: Journal of Environmental Radioactivity - Volume 99, Issue 8, August 2008, Pages 1329–1334