peer reviewed | It is now irrefutable that air pollution caused by large amounts of Total Suspended Particulates (TSP) and respiratory particulates or Particulate Matter less than 10 mu m in aerodynamic diameter (PM10) has numerous undesired consequences on human health. Air quality degradation far from the African continent, in the US and in Europe, caused by high concentrations of African dust, is seen as a major threat even though most of these countries are very distant from the Sahara. Surprisingly, no estimates of TSP or PM10 levels near the Saharan dust source are available. Based on horizontal visibility observations which are reduced by the presence of dust in the atmosphere, TSP and PM10 levels are estimated throughout the year 2000 at Nouakchott-Airport, Mauritania, using relations found in the literature. It appears that concentrations of particles are significant both in terms magnitude and frequency, as the 24-hour PM10 thresholds established by the US EPA National Ambient Air Quality Standards and the EU Limits Values for Air Quality were exceeded 86 and 137 times, respectively. The average annual concentration is far above air quality standards and estimated at 159 mu g m(-3) for TSP and 108 mu g m(-3) for PM10. These very high particulate levels are likely to represent an important public health hazard and should be considered as a major environmental risk.

The quantification of entanglements of megafauna with plastic debris at sea is difficult to assess for several reasons, such as detection and reporting biases. We used standardized vessel based counts to describe and quantify the occurrence of marine debris entanglements in northern gannets Morus bassanus at five of its main wintering areas. We observed 34 entangled birds in total, representing 0.93% of all gannets counted (n=3672 individuals). The incidence of entanglements largely varied geographically, being exceptionally high off Mauritania (20.2% of the birds in late spring). Most birds affected were immature (1.88% compared to 0.06% in adults), which in turn represented 52.4% of all the birds. Entanglements in the lower bill mandible were the most frequent, mainly with red-colored plastic objects. Further research is urgently needed to evaluate the impact of entanglements at the population level and its occurrence in other marine species, and to seek potential solutions.

Levrier Bay is an important fishing area which is under growing anthropogenic pressures seriously threatening this treasure. Among these pressures Polycyclic Aromatic Hydrocarbon are of great environmental concern. Therefore, 16 EPA-PAHs were analyzed using GC–MS in Perna perna species and sediment. Comparison with Dakar (Senegal) and Moroccan coasts shows that PAHs levels are strikingly lower than that of heavily polluted Dakar coast (2474 μg/kg); nevertheless, comparable to Moroccan Casablanca and Tangier coasts (245 and 351 μg/kg, respectively). Ratio analysis indicates the predominance of pyrogenic sources and partial contribution of automotive traffic for the half of 4 sites. Furthermore, statistical analys shows that there are no significative differences, except for Benzo(b)Fluorentene in P. perna tissue and 4 PAHs (Fluorene; Fluorenthene; Pyrene; diBenzo(ah)Anthracene and dBahANT) in sediment for sites samples. Furthermore, bioconcentration indicates that P. perna is an excellent PAHs bioindicator. This points the necessity for immediate introduction of a sound Pollutants monitoring system.

It is now irrefutable that air pollution caused by large amounts of Total Suspended Particulates (TSP) and respiratory particulates or Particulate Matter less than 10 μm in aerodynamic diameter (PM₁₀) has numerous undesired consequences on human health. Air quality degradation far from the African continent, in the US and in Europe, caused by high concentrations of African dust, is seen as a major threat even though most of these countries are very distant from the Sahara. Surprisingly, no estimates of TSP or PM₁₀ levels near the Saharan dust source are available. Based on horizontal visibility observations which are reduced by the presence of dust in the atmosphere, TSP and PM₁₀ levels are estimated throughout the year 2000 at Nouakchott-Airport, Mauritania, using relations found in the literature. It appears that concentrations of particles are significant both in terms magnitude and frequency, as the 24-hour PM₁₀ thresholds established by the US EPA National Ambient Air Quality Standards and the EU Limits Values for Air Quality were exceeded 86 and 137 times, respectively. The average annual concentration is far above air quality standards and estimated at 159 μg m-³ for TSP and 108 μg m-³ for PM₁₀. These very high particulate levels are likely to represent an important public health hazard and should be considered as a major environmental risk.

Rapid population growth and poor waste management practice are among the main drivers of plastic pollution in modern times, thus making Africa a hotspot for plastic pollution both now and in the future. This study is a review of plastic pollution reports from the African aquatic environment with regard to causes, current status, toxicological implications and implications for ecosystem services. A total of 59 plastic pollution studies from 1987 to September 2020 were reviewed. They comprised 15 from North Africa (NA) (Algeria, Egypt, Morocco and Tunisia), six from East Africa (EA) (Ethiopia, Kenya, Tanzania and Uganda), 13 from West Africa (WA) (Ghana, Guinea-Bissau, Mauritania and Nigeria), and 25 studies from Southern Africa (SA) (South Africa). This shows that plastic pollution studies in Africa, according to the sub-regions, are in the order: SA > NA > WA > EA. High human population in the basins of African large aquatic systems is identified as the greatest driver enhancing plastic surge in the aquatic environment. The occurrence of plastics was mostly reported in the estuarine/marine environment (42 studies) compared to the freshwater environment (only 17 studies). Plastics have also been reported in the three compartments of the aquatic environment: water column, benthic sediment and animals. Zooplankton, annelids, molluscs, insects, fishes and birds were reported as bioindicators of plastic ingestion in the inland and coastal waters of Africa. Polyethylene, polyethylene terephthalate (polyester) and polypropylene were the common plastic polymers observed in the African aquatic environment. In situ toxicological implications of the ingested plastic polymers were not reported in any of the studies. However, reports from laboratory-controlled experiments showed that these polymers are deleterious to aquatic animal health. More research efforts need to delineate the plastic pollution status of the East, West and North of Africa. Furthermore, such studies are required to identify the plastic polymers and in situ ecotoxicological impacts of plastics on both animal and human health.

North Africa coastline extends on 8955 km from Mauritania to Egypt. These areas continue to experience population and economic growth. North Africa coastal aquifers were exposed to an increase in groundwater salinity and seawater intrusion, which may contribute to economic crisis as a result of freshwater resources crisis. This work aims to explore the status and a holistic comprehending review of saltwater intrusion extent in the region and future challenges. Results on seawater intrusion in North Africa, from published papers and grey literature, show a several efforts have been made in understanding this phenomenon and developing management strategies in Egypt, Libya, Tunisia, Algeria, Morocco, and Mauritania. The most method used is geochemical data and statistical analysis. Some studies linked geochemical data with geophysical techniques, geographical information system (GIS), and GALDIT index. Seawater intrusion varies from one country to another according to the aquifer hydrogeological settings, abstraction rates and aquifer morphology, climate change, urban expansion, and economic development. North Africa countries, such as Libya and Mauritania, need, for instance, more expertise and experience on the part of local researchers. The challenge of inadequate data and a need for a more robust data inventory was stressed. This paper recommends developing and building scientific capabilities in regional and international partnerships, and adopting rational water governance for sustainable development.