Environmental occurrence of phthalate and organophosphate esters in sediments across the Gulf of Lion (NW Mediterranean Sea)

Seven phthalate (PAEs) and nine organophosphate esters (OPEs) were measured in surface sediments across the Gulf of Lion (NW Mediterranean Sea) at twelve stations characterized by different anthropogenic signatures. Sigma PAEs and Sigma OPEs concentrations ranged from 2 to 766 ng/g DW (av. 196 ng/g DW) and from 4 to 227 ng/g DW(av. 54 ng/gDW), respectively. Our analysis of the potential sources of these organic plastic additives in sediments of the Gulf of Lion suggests that the dominant factors affecting their occurrence and environmental distribution are port-based industrial activities and urban pressures. Indeed, the highest Sigma PAEs and Sigma OPEs concentrations were found close to the ports of Toulon and Marseille (Estaque) and at the sites impacted by the Marseille metropolitan area (i.e. at the outlets of the waste water treatment plant at Cortiou and at the mouth of the Huveaune River). The lowest levels were generally found in protected areas (e.g. Port-Cros) and at sites relatively far from the coast. DEHP was seen to be the most abundant PAE while TDCP, TEHP and TiBP were the most abundant OPEs in the area. Our results also expose the contribution of additives entering the Gulf of Lion via sedimentary material from the Rhone River, with positive correlations between the total organic carbon (TOC) content in the sediment and the Sigma PAEs and Sigma OPEs concentrations. However, additive concentrations decreased from shore to offshore in the Rhone River discharge area, indicating an efficient dilution of the contaminants accumulated at the river mouth area. (C) 2020 Elsevier B.V. All rights reserved.

Automated summary

The study indicates that the main sources of phthalate and organophosphate esters in sediments along the Gulf of Lion are port-based industrial activities and urban pressures. The concentrations of organic plastic additives vary at different locations, influenced by protected areas and sites far from the coast.