Pollution of water in Africa: a review of contaminants and fish as biomonitors and analytical methodologies-the case of Senegal.

Environmental pollution is one of the major problems facing human health, ecosystems, and biodiversity. This is particularly the case for water quality in Senegal. Fish can be used as a biomonitor of pollution by accumulating pollutants from the environment through their tissues. Fish is an indispensable element in the assessment of the quality of the environment due to the diversity of biological cycles and their position in the food chain. Fish, which is very sensitive to chemical and bacterial pollution, concentrates pollutants and is a good indicator of water quality. This review presents water pollution in Senegal and the possibility of using fish as an ideal monitoring matrix for marine environments, to detect the concentration of heavy metals and organic pollutants. The different extraction and analytical techniques used for fish biomonitoring will be also described.

Application of the QuEChERS method for the determination of pesticides, PAHs and PCBs in fish in Senegal.

Pollution of water by persistent organic pollutants is well described; however, little is known about the accumulation of these pollutants by aquatic organisms. For this reason, a method based on QuEChERS extraction and gas chromatography coupled to tandem mass spectrometry (GC-MS/MS) was developed for the determination of pesticides, polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) in the muscles of five fish species from the bay of Soumbedioune (Dakar, Senegal). This method shows good recoveries of extraction (68.2-98.1% for pesticides, 83.87-98.10% for PAHs and 81.30-98.15% for PCBs), precision (% RSD ≤ 1%), sensitivity (LODs between 0.001 and 0.079 ng g-1), linearity (R2 ≥ 0.99) and repeatability and reproducibility, evaluated for three concentration levels (10 ng g-1, 200 ng g-1 and 500 ng g-1), ≤ 15% for the majority of pollutants under study except for alachlor, atrazine, acetochlor, dicofol, deltamethrin and dichlorvos where a RSD ≥ 20% was determined for the 10 ng g-1 concentration. Organic pollutants have been detected in fish from the Soumbedioune coast demonstrating the necessity of a regular survey of water and fish in order to protect the populations.

[Breast abscess: epidemiological, diagnostic and therapeutic features in patients hospitalized in the Main Hospital in Dakar]. / Abcès du sein: aspects épidémiologiques, diagnostiques et thérapeutiques à l'Hôpital Principal de Dakar.

Breast abscesses are neoformed collections of purulent matter occupying the mammary gland and the periglandular tissue. They can occur both in lactating or non-lactating women. The purpose of our study was to describe the epidemiological, diagnostic and therapeutic features of breast abscesses in patients hospitalized in the Division of General Surgery at the main hospital in Dakar. We conducted a retrospective, descriptive study involving all patients treated for breast abscess over a 4-year period. We collected data from 41 medical records of female patients. The average age of patients was 31 years. The main risk factor was mastitis during lactation (27%). The average time of progression was 12 days, ranging from 1 to 30 days. Left abscesses were reported in 61% of cases and mostly manifested as an inflammatory swelling (88%). Upper quadrants were mainly involved (43.9%). Breast ultrasound was performed in 51.2% of female patients. Surgical drainage under general anesthesia was performed in all female patients. The mean quantity of pus was 119 cc. Staphylococcus aureuswas the most commonly isolated germ (79.5%). The average length of stay in hospital was 7 days and operative morbidity was 31.7%. Mortality was zero. Prevention of abscesses during lactation is based on improving breastfeeding practices and on early antibiotic treatment in patients with mastitis.