{'fraction_non_alphanumeric': 0.01554001554001554, 'fraction_numerical': 0.003108003108003108, 'mean_word_length': 5.924731182795699, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Polycyclic aromatic hydrocarbons in surface sediments of the open Aegean Sea: Contribution of Maritime traffic

Polycyclic aromatic hydrocarbons (PAHs) were investigated in surficial sediments collected from 39 stations in the open Aegean Sea, in order to assess their occurrence, distribution and major sources. Total PAH concentrations were generally low, comparable to those reported in relatively unpolluted marine areas. The highest values were recorded in the northern part Aegean Sea, which apparently receives more anthropogenic inputs both from continental runoff and atmospheric deposition. Several diagnostic criteria were used to investigate PAHs’ origin. Their molecular profile reveals contributions from both pyrolytic and petrogenic sources, with their relative importance displaying significant regional variability. Phenanthrenes, which are known to mostly originate from unburned fossil fuels were found in percentages higher than 50% in the Central part of Aegean Sea and their occurence was correlated with the marine traffic in the area. The PAH concentrations are significantly correlated with the total organic carbon (TOC) content of sediments, which indicates that the latter exerts an important control on their transport and ultimate accumulation in sediments