Economic losses related to the reduction of Posidonia ecosystem services in the Gulf of Gabes (Southern Mediterranean Sea).

In the early XXth century, the Gulf of Gabes in SE Tunisia used to host the most extended Posidonia oceanica seagrass beds in the Mediterranean basin and was a highly productive hotspot of benthic species. Since the 70's, >500 million t of wet toxic phosphogypsum discharges from a fertilizer industrial complex have led to the gradual loss of ∼90 % of its initial surface. This drastic shrinkage is accompanied by significant value losses originated from the direct and indirect-use services of which the most important ones are small scale fisheries and carbon storage function.

PET plastics as a Trojan horse for radionuclides.

Mismanaged plastic waste interacts with secondary environmental pollutants, potentially aggravating their impact on ecosystems and human health. Here we characterized the natural and artificial radionuclides in polyethylene terephthalate (PET) bottles collected from the industrial littoral discharge of a phosphate fertilizer plant. The activity concentrations in littered bottles ranged from 0.

Rare earth elements characterization associated to the phosphate fertilizer plants of Gabes (Tunisia, Central Mediterranean Sea): Geochemical properties and behavior, related economic losses, and potential hazards.

This is the first study on the behavior and industrial fluxes of rare earth elements (REE) in the coastal fertilizer plants of Gabes (south-eastern Tunisia), the economic losses related to their wastes, and their environmental and human health hazards. The concentrations of 16 REE were assessed in phosphate rock (PR), phosphogypsum (PG) and phosphogypsum foam (PGF) samples, collected from Gabes plants. REE concentrations ranged from 0.

Surface sediment enrichment with trace metals in a heavily human-impacted lagoon (Bizerte Lagoon, Southern Mediterranean Sea): Spatial distribution, ecological risk assessment, and implications for environmental protection.

Although several studies previously assessed the contents of trace metals in the sediments of the heavily human-impacted lagoon of Bizerte (northern Tunisia), multi-analytical approaches have not been, so far, used to assess the ecological risks in this water body. This study attempts to provide a comprehensive ecological risk assessment related to the enrichment of the lagoon sediments with seven metals (As, Cd, Cr, Cu, Hg, Pb, and Zn). Significant spatial variations were found in the metal concentrations in sediments, in relation to the degree of coastal human activities and hydrodynamics.

Economic impact of human-induced shrinkage of Posidonia oceanica meadows on coastal fisheries in the Gabes Gulf (Tunisia, Southern Mediterranean Sea).

In early XXth century, the Gulf of Gabes (SE Tunisia) used to host the most extended Posidonia oceanica seagrass beds in the Mediterranean Sea, and a highly productive hotspot of benthic/demersal biodiversity. Sponge harvesting and seabed trawling provoked a first step of seagrass degradation. Subsequently, phosphogypsum releases from Gabes Industrial Complex, since mid-1970s, accelerated the decline of the remaining patches.

Natural radioactivity and radiation hazard assessment of industrial wastes from the coastal phosphate treatment plants of Gabes (Tunisia, Southern Mediterranean Sea).

This work is a first contribution to the knowledge of natural radionuclides (Ra, U, K, and Th) activities in phosphate rock (NORM), phosphogypsum, and phosphogypsum foam (TENORM) from the coastal fertilizer plants of Gabes (Southeastern Tunisia) and the assessment of their radiation hazards on human health and the surrounding environment. In the three studied materials, activities were found to be in the range of 35.4 (K)-375.

Characterization of the role of phosphogypsum foam in the transport of metals and radionuclides in the Southern Mediterranean Sea.

The Gabes Gulf had received huge quantities of phosphogypsum discharged from fertilizer plants. Dumping phosphogypsum in coastal waters leads to the formation of foam layers which can float on the surface and be passively transported to distant areas. This is the first attempt at geochemical and mineralogical characterization of these industrial foams in order to understand their role in the dynamic and behavior of contaminants in marine environment.

Characterization of phosphate rock and phosphogypsum from Gabes phosphate fertilizer factories (SE Tunisia): high mining potential and implications for environmental protection.

Since the establishment of the coastal industrial complex in Gabes city (Gulf of Gabes, SE Tunisia), hundred million tons of untreated phosphogypsum have been discharged in the open sea causing serious environmental problems. To better understand the dynamic and behavior of phosphate/phosphogypsum contaminants from raw ores to marine environment, a chemical, organic, mineralogical, and morphological characterization of phosphate rock and phosphogypsum was conducted using several sophisticated techniques. The chemical analysis showed that phosphate and phosphogypsum contain high loads of trace elements and that the transfer factors of pollutants varied from 5.

Seawater quality assessment and identification of pollution sources along the central coastal area of Gabes Gulf (SE Tunisia): Evidence of industrial impact and implications for marine environment protection.

Temperature, pH and trace elements (F, P, Cr, Cu, Zn, Cd, and Pb) contents were determined in 16 stations as well as in 2 industrial and 2 domestic discharge sources, in the central coastal area of the Gulf of Gabes. Compared to the northern and southern areas of the study area, the highest contents of contaminants were reached in the central area which hosts the coastal industrial complex. The seawater in this central area was also found to be acid and of higher temperature.

Biomonitoring of coastal pollution in the Gulf of Gabes (SE, Tunisia): use of Posidonia oceanica seagrass as a bioindicator and its mat as an archive of coastal metallic contamination.

Within the framework of a study on the extent and history of marine pollution in the central area of Gabes Gulf, the concentrations of four trace metals (Cd, Cu, Pb, and Zn) were assessed in three different tissues of the seagrass species, Posidonia oceanica (leaves, rhizomes, and roots), in the mat of P. oceanica meadows at different depths from the sea floor (- 30 to - 150 cm) and in sediments. The results showed that P.

Metal concentration and bioaccessibility in different particle sizes of dust and aerosols to refine metal exposure assessment.

Refined exposure assessments were realized for children, 7-9yrs, in the mining/smelting city of Oruro, Bolivia. Aerosols (PM>2.5, PM1-2.

Heavy metal contamination and ecological risk assessment in the surface sediments of the coastal area surrounding the industrial complex of Gabes city, Gulf of Gabes, SE Tunisia.

In the present study, the concentrations of 6 trace metals (Hg, Cd, Cu, Pb, Cr and Zn) were assessed in the surface sediments of the central coastal area of Gabes Gulf to determine their contamination status, source, spatial distribution and ecological risks. The ranking of metal contents was found to be Zn>Cd>Cr>Pb>Cu>Hg. Correlation analysis indicated that Cd and Zn derived mainly from the Tunisian Chemical Group phosphogypsum.