Phosphate industry discharges and their impact on metal contamination and intertidal macrobenthos: Jorf Lasfar and Safi coastlines (morocco)

Abstract

At Jorf Lasfar and Safi, on the Moroccan Atlantic coastline, there are chemical industry plants that produce phosphate derivates including phosphoric acid and fertilizers, together with by-products such as sulphuric acid. The liquid effluents of the plants are discharged directly into the sea. In order to evaluate their impact, we have compared the distribution of intertidal macrobenthos in several locations, along gradients subjected to differing degrees of phosphate industry pollution. The results illustrate how biological diversity and species densities decrease abruptly in the vicinity of these industrial effluents, and also how recovery, as measured by the same parameters, proceeds with distance from the discharge points. Mussels Mytilus galloprovincialis were heavily contaminated by Cu and Cd at both study locations and their shells showed four kinds of deformities, notably at the Jorf Lasfar site, where the effluents were more aggressive (high in metals, low pH).

Metal concentrations in sediments and clams in four Moroccan estuaries

“…Data on Cd in Moroccan aquatic systems are less abundant than for other metals. The few recent studies that were carried out in lagoons and estuaries (Benabdellaoui, 1994;Cheggour et al, 2000;Cheggour et al, 2001;El hachadi, Cheggour, Ghamizi, & Idrissi, 1999;Mazlani, 1995) and in coastal systems (Cheggour, Langston, Chafik, Texier, & Idrissi, 1999;Idhalla, 1997;Tahiri & Lazzabi, 1991) pointed out the role of human activities in Cd loadings, in agreement with other studies (Bopp & Biggs, 1981;Madsen & Larsen, 1986).…”

The distribution of heavy metals in the Sidi Moussa lagoon sediments (Atlantic Moroccan Coast)

“…The proximity of the lagoon to the phosphate processing plants based 15 km to the Northeast, in Jorf Lasfar, is almost certainly most important. Industrial effluent of this complex will reflect the enrichment in metals from the phosphate being processed (Cheggour et al, 1999). The water along the Moroccan Atlantic coast between Jorf Lasfar and Safi showed some deterioration in quality at stations affected by heavy urban and industrial activities and, consequently, at least a part of these metals (Cr, Zn, and Cu) may reach the Sidi Moussa lagoon.…”

Comparative study of potential transfer of natural and anthropogenic cadmium to plankton communities in the North-West African upwelling

“…These high Cd concentrations are attributed to anthropogenic influence (i.e. phosphate industry, Banaoui et al, 2004;Cheggour et al, 1999;Maanan, 2008Maanan, , 2007Romeo et al, 2000;Sidoumou, 1991;Sidoumou et al, 2006Sidoumou et al, , 1999Sidoumou et al, , 1992). In the model, the anthropogenic impact in the coastal area is mainly restricted to the vicinity of the anthropogenic sources located north of Cape Sim (Fig.…”

“…Thus, the Moroccan phosphate industry releases large amounts of heavy metals, particularly cadmium (Cd), in the North-West (NW) African upwelling around Safi and Jorf-Lasfar (33°N). Locally, these are responsible for a significant contamination of molluscs communities (Banaoui et al, 2004;Benbrahim et al, 2006;Chafik et al, 2001;Cheggour et al, 1999;Gaudry et al, 2007;Maanan, 2008Maanan, , 2007. As a consequence, mussels for instance are considered unfit for human consumption in this region (Moustaid et al, 2005).…”