Polycyclic Aromatic Hydrocarbon Degradation and Sorption Parameters in Coastal and Open-Sea Sediment

Abstract

This work describes the experimental determination of the major degradation and sorption parameters of polycyclic aromatic hydrocarbons (PAHs) in a sensitive marine environment, the Northern Adriatic Sea (Mediterranean Sea). The persistence and sorption of complex PAH mixtures were analysed in the laboratory in conditions mimicking open-sea and coastal sediments, which differ in grain size and organic carbon content and are characterized by different oceanographic conditions including abiotic influences. The study investigated how sediment type and texture and salinity, temperature and solar irradiation conditions affect the partitioning of low molecular weight (LMW) and high molecular weight (HMW) PAHs into aqueous and solid phase, which critically influence their behaviour. With regard to the change from offshore to coastal conditions, HMW PAHs were found to be more sensitive to the increased salinity (from 21 to <37 parts per thousand), whereas LMW PHAs were more sensitive to the temperature increase (from 11 to 22°C). HMW PAHs were more affected by sediment type changes in terms of distribution coefficient (K d ). Since the physicochemical properties of organic pollutants affect their distribution, transport, bioavailability and toxicity, analysing the accumulation and persistence of dissolved pollutants can provide useful information for environmental risk assessment and management.

Meta-Analysis of a New Georeferenced Database on Polycyclic Aromatic Hydrocarbons in Western and Central Mediterranean Seafood

“…Moreover, in summer, the degradation of PAHs, especially of the lighter ones (i.e., LMW PAHs) [63,64], is enhanced by UV radiation, high temperatures, and ozone [65]. On the other hand, low seawater temperature in winter can inhibit the microbial degradation of PAHs [66,67]. Additionally, the resuspension of particulate matter that takes place during winter via sea storms [19] and water mixing [12] could foster PAHs availability and accumulation in filter feeding organisms, such as mussels, and this is particularly true for heavier and more recalcitrant PAHs [12,68].…”

Role of environmental factors and microorganisms in determining the fate of polycyclic aromatic hydrocarbons in the marine environment

“…2016). Laboratory experiments have demonstrated that PAH partitioning towards the sorbed phase is controlled by sediment grain size, salinity and temperature (Frapiccini and Marini 2015). …”

Polycyclic aromatic hydrocarbon (PAH) accumulation in different common sole (Solea solea) tissues from the North Adriatic Sea peculiar impacted area

“…Due to their lipophilicity, low solubility in water and high persistence, PAHs naturally tend to be adsorbed in suspended matter, and then result in relatively rapid deposition in marine sediments (Cheung et al, 2007;Koelmans et al, 2010;Cui et al, 2016). Their hydrophobicity, namely octanol-water partition coefficient (Kow), is the dominant physical parameter for the fate of PAHs, as it determines their capacity for transport and distribution between different environmental compartments as well as their uptake and accumulation by living organisms (Chu & Chan, 2000;Frapiccini and Marini, 2015;Hussein et al, 2016). PAH bioaccumulation is also influenced by other physicochemical characteristics, such as number of rings, type and origin, environmental conditions (e.g.…”