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The objective of the present paper was to investigate the potential of urban wastes derived soluble bioorganic substances (SBO) to perform as auxiliaries for enhanced washing of urban soil contaminated by industrial activities. The second objective was to show how the SBO could be used for remediating the environmental impact caused by industrial activities and, at the same time, be compatible with the real-world situation demanding zero waste processes. The SBO, isolated from four urban biowastes, were characterized for their lipophilic/hydrophilic (LH) and aliphatic/aromatic C ratios, and for their surface activity properties. Soil, containing about 0.45 % w/w polycyclic aromatic hydrocarbons (PAHs), was sampled from a dismissed coal gasification site. The efficiency of the SBO for washing the contaminated soil was investigated. The most lipophilic SBO, in spite of the highest surface activity, was the least efficient. The products having lower LH, poorer surface activity, but higher concentration of aromatic C were more efficient. All SBO allowed developing a two steps process. This comprised soil washing, and the recovery and chemical treatment of the washing solution, to yield a PAHs-SBO precipitate and the clean water phase to recycle to further soil washing. Data were obtained under the same experimental conditions using Triton X-100 commercial surfactant. The results indicated that, although the commercial surfactant is the most efficient in the soil washing step, it does not allow removal of PAHs from the recovered washing solution. On the contrary, 95-99 % PAHs removal from the recovered SBO washing solutions is attained.

Residual biological effects of the 1991 HAVEN oil spill off the Ligurian (Arenzano) coast were assessed in this study. Samples of the fish species Boops boops, Mullus barbatus, and Uranoscupus scaber were collected from two polluted sites near the HAVEN wreck and from an uncontaminated area. In addition to this, mussels were caged along the coast affected by the HAVEN disaster. The physiological status of fish and mussels was assessed using a battery of stress and exposure biomarkers. The PAH content of mussel and fish tissues was also analyzed. Significant biological responses were observed in lysosomal membrane stability, neutral lipid and lipofuscin accumulation and micronucleus frequency for mussels caged at two sites close to the HAVEN wreck. Chemical analyses indicated, however, that these effects are not caused by aromatic hydrocarbons. For this reason, we suggest that the aftermath of the HAVEN disaster contributes very little to coastal ecosystem pollution. This was also confirmed by the few biological effects observed in fish specimens (Boops boops) collected from surface waters. Nevertheless, it is important to point out that benthic fish displayed a stress syndrome potentially caused by aromatic hydrocarbons released from the oil tanker, as witnessed by an enhanced EROD activity and increased lipofuscin and neutral lipid lysosomal contents.

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