Remobilization of polycyclic aromatic hydrocarbons and organic matter in seawater during sediment resuspension experiments from a polluted coastal environment: Insights from Toulon Bay (France)

• Published in: Environmental pollution (1987) 2017-10, Vol.229, p.627-638
• Main Authors: Guigue, Catherine, Tedetti, Marc, Dang, Duc Huy, Mullot, Jean-Ulrich, Garnier, Cédric, Goutx, Madeleine
• Format: Article
• Language: English
• Subjects: Bays; Earth Sciences; Environmental Monitoring; Environmental Sciences; Fluorescent dissolved organic matter; France; Geologic Sediments - chemistry; Mediterranean Sea; Oceanography; Organic Chemicals - analysis; Polycyclic aromatic hydrocarbons; Polycyclic Aromatic Hydrocarbons - analysis; Remobilization; Sciences of the Universe; Seawater - chemistry; Sediment resuspension; Sediment-water partition; Water Pollutants, Chemical - analysis
• ISSN: 0269-7491; 1873-6424
• DOI: 10.1016/j.envpol.2017.06.090

Polycyclic aromatic hydrocarbons (PAHs) and organic matter contents were measured in seawater during resuspension experiments using sediments collected from Toulon Bay (Northwestern Mediterranean Sea, France). The studied sediments were very highly contaminated in PAHs, especially in 4-ring compounds emitted from combustion processes. The sediments used for resuspension experiments were collected at 0–2 cm (diagenetically new organic matter, OM) and 30–32 cm depths (diagenetically transformed OM). They were both mostly composed of fine particles ( Koc predicted from Kow). The results confirmed the sequestration role of sedimentary OC quality and grain size on PAHs; the OM diagenetic state seemed to impact the partition process but in a relatively minor way. Furthermore, differences were observed between 2-4 ring and 5–6 ring PAHs, with the latter displaying a relatively higher mobility towards seawater. These differences may be explained by the distribution of these two PAH pools within different OM moieties, such as humic substances and black carbon. [Display omitted] •High PAH concentrations and OC content in sediments from Toulon Bay (France).•Sediment resuspension induced a remobilization of PAH and OM into seawater.•Benzo[g,h,i]perylene concentration exceeded toxicity threshold after resuspension.•Coupling between dissolved PAHs and humic-like material released in seawater.•log Koc confirmed the role of sedimentary OM on PAH sequestration in particles.