Trace metal distribution in the mussel Perna perna along the Moroccan coast

摘要

The marine environment plays a highly important socioeconomic role in Morocco. Very high biological productivity due in particular to an intense coastal upwelling makes the Moroccan coast one of the most productive areas in the world. However, this coast is affected by several discharges of untreated industrial and domestic waste (Moukrim et al., 2000), particularly the northern part of the Atlantic coast affected in certain places by an important chemical contamination (Cheg-gour et al., 2000; Chafik et al., 2001). The purpose of the present study is to provide a synoptic view of the contamination of the Moroccan coast by trace metals. Comparable data on quality have been acquired for regions as different as (1) the Mediterranean coast belonging to a partially closed marine environment shared with other industrialized countries (Spain, France, Italy, etc.), (2) the industrialized and urbanized northern Atlantic coast (particularly the Jorf Lasfar-Safi sector highly developed for the phosphate industry), (3) the sparsely populated, semi-desert south Atlantic coast, which is subject to upwelling. Due to its more extensive geographical distribution along the Moroccan coast, the African mussel Perna perna has been preferred to Mytilus gallopromncialis as the sentinel species for the study. Samples were collected in accordance with international recommendations, i.e. uniform sets, comparable mussel size from one site to another, sampling at all sites in the spring when the sexual activity of the organisms does not affect contaminant concentrations, and analytic methods, performed according to quality assurance standards.