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Abstract 2.1 Marine pollution In general, pollution is the introduction of contaminants into an environment that cause ~ instability, disorder, harm or discomfort to the ecosystem i.e. physical systems or living organisms. Pollution can take the form of chemical substances or energy such as noise, heat, or light energy. Pollutants, the elements of pollution, may be naturally or foreign substances produced due to human activities, they are considered contaminants when they exceed natural levels. Pollution is often classed as point source or non-point source pollution 1261. One of the most adequate definitions of marine pollution is the introduction of substances or energy by man, directly or indirectly, into the marine environment resulting in such deleterious effects as harm to living resources, hazards to human health, hindrance to marine activities including fishing, impairment of quality for use of seawater and reduction of amenities [271. Mediterranean pollution, different activities have been identified as sources of pollution to the Mediterranean Sea and its coastal area: i.e., municipal wastewaters, industrial waste discharges, accidents and transport of chemicals by ship traffic and bay activities, agricultural run-off of chemicals used in agriculture by surface and drainage waters, air-borne inputs, etc. The current human coastal population is about 130 million, although this figure depends very much on where the boundaries of the coastal zone are drawn. Of this population, about 40% concentrate on the coast and this figure. is expected to be doubled by year 2025 1281. This pressure results in the intensification of economic activities, especially agricultural and industry production, which in turn places increasing demands on water resources. It was estimated that more than 80% of the pollution load in the Mediterranean Sea came from land sources [281 mainly in the form of still largely uncontrolled discharges of municipal and industrial wastes, which reached the sea both directly from coastal sources and indirectly through rivers 1231. . Of all marine pollutants, hydrocarbons have received the greatest attention due primarily to the highly lethal effects of most hydrocarbons on marine organisms, especially aromatics class. Hydrocarbons as potential environmental contaminants are an assemblafje of substances coming from various sources including biogenic, petrogenic and pyrolytic 124-3 I. There are two main categories of hydrocarbon compounds, aliphatic and aromatic fractions, in this study we will concern our attention on aliphatic and a group of aromatic compounds known as polycyclic aromatic hydrocarbons (PAHs). Both fractions are considered as a unique class of persistence organic pollutants (POPs) contaminating the marine environment and have been studied as regards to their origin and distribution in the environment [34-381. 2.2 Sources of pollution Emissions may be arisen from natural processes and anthropogenic activities, although the later generally predominate. Natural emission occurs naturally and won’t cause excessive harm to our lives due to its re~eneration, while the anthropogenic is caused by human activities and hard to get rid of [3 -411. Figure (2.1) shows the different sources and processes generating different contaminants into environments. 2.2.1 Anthropogenic sources Human activities such as oil transportation, oil spill, shipping and industrial, storm water and domestic discharge are believed to be important influenced sources of pollutants in . |