Pollutant lead reveals the pre‐Hellenistic occupation and ancient growth of Alexandria, Egypt

Abstract

It is generally accepted that Alexandria ad Aegyptum was founded ex nihilo in 331 BC by Alexander the Great, rapidly growing into one of antiquity's most opulent economic and intellectual centers. However, ancient texts by Strabo (17.1.6) and Pliny (NH 5.11.62) suggest the existence of a pre‐Hellenistic settlement named Rhakotis. This literary evidence has fuelled contentious scholarly debate for decades. Here we present new geochemical data from Alexandria's ancient bay sediments, elucidating unequivocal proof for pollutant lead (Pb) input into the harbor during the Egyptian Old Kingdom (2686–2181 BC). A second contamination peak is detected during the Iron Age (1000–800 BC), at the end of the prosperous Ramesses reigns. These findings evidence thriving pre‐Hellenistic settlements in Alexandria. During the Greek and Roman periods, we expound the largest Pb pollution ever encountered in ancient city sediments with Pb levels twice as high as those measured in contemporary industrialized estuaries.

Tracing the Alkinoos Harbor of ancient Kerkyra, Greece, and reconstructing its paleotsunami history

“…As early as the 1st millennium B.C., Pb pollution appeared as a result of ore treatment and the byproduct of silver smelting (Hong, Candelone, Patterson, & Boutron, 1994; Lessler, ). During Roman times, Pb production reached extraordinarily high levels in places (Véron et al., ). Ancient Pb contamination has been documented in the Tiber River and Roman harbors of Portus, Marseille, and Sidon (Delile, Blichert‐Toft, Goiran, Keay, & Albarède, ; Le Roux, Véron, & Morhange, , ).…”

Lead Use on Roman Ships and its Environmental Effects

“…In closed basins, as found in some ports, there was little exchange of water and the lead accumulated in the sediment. Sedimentological studies carried out in the ancient harbours of Sidon (modern Saida), just north of the Israeli coast, and Alexandria, have revealed an increase in anthropogenic lead deposited in the bottom sediment during the Roman period, which was assumed to have been caused by industrial effluence from the town (Roux et al , 2003; Véron et al , 2006). Sidon was known more as a port and less as a metallurgical site; the lead accumulation was probably caused by ship‐borne lead, corroborating the thesis presented here.…”

“…Sidon was known more as a port and less as a metallurgical site; the lead accumulation was probably caused by ship‐borne lead, corroborating the thesis presented here. As for Alexandria, it was said: ‘During the Greek and Roman periods, we expound the largest Pb pollution ever encountered in ancient city sediment with Pb levels twice as high as those measured in contemporary industrialized estuaries’ (Véron et al , 2006: 3). Mooring and anchoring sailors often fished in harbours, as indicated by recovered fishing‐gear sinkers (Oleson, 1994b; Kingsley and Raveh, 1996).…”

Demise of a harbor: a geochemical chronicle from Ephesus

“…Lead isotopes constitute a complementary tool in that they play a critical role wherever their compositions can be ascribed to anthropogenic influence in the form of lead and heavy metal pollution of sediments accumulated in harbors, which are highly efficient traps for clays and suspensions. Anthropogenic impact using Pb isotopes as a tracer has so far been documented for the ancient harbors of Alexandria (V eron et al, 2006Stanley et al, 2007), Sidon (Le Roux et al, 2003), Marseilles (Le Roux et al, 2005), and Rome (Delile et al, 2014a).…”