Assessment of Metal Pollution in Umm el-Surab Archaeological Layers, Northeast Jordan

This study aims to assess the extent of the anthropogenic pollution of Area A at the Umm el-Surab archaeological site, Jordan. It examines the concentrations of 21 metals from four Roman, Byzantine, and early and late Ayyubid-Mamluk layers. The site, located near Bosra and Umm el-Jimal, was continuously settled from the Roman till the Islamic periods. The chemical analysis and pollution indices (enrichment and contamination factors (EF, CF), and geo-accumulation index Igeo) show low enrichment in Zn, K, Sr, Na, Pb, Ba, Li, Mn, Mg, Mo, and Cu, and moderate enrichment in Cd, Ag, Ca, As, and Ni. Co is significantly enriched in one sample and moderately enriched in the other ones. The results show pollutant metals more enriched in the Byzantine layer than the rest of the layers. A likely primary source of the limited pollution is organic fuels and their firing product of ash, while a likely secondary source might be the pottery fragments spread in the layers. The results agree with the fact that the site was rural with limited industrial activities, especially metal production, like iron and copper, that would have increased the concentration of the analyzed metals.