La collaboration avec l'Université Quisqueya d'Haïti

L'université doit se reconstruire sur les ruines des bâtiments qui venaient d'être construits.

La collaboration avec l'Université Quisqueya d'Haïti : tristesse et reconstruction

Ketty Balthazard-Accou, Evens Emmanuel, Patrice Agnamey, Philippe Brasseur, Obicson Lilite, Anne Totet, Christian Raccurt. Presence of Cryptosporidium oocysts and Giardia Cysts in the surface water and groundwater in the City of Cayes, Haiti. AQUA-LAC, Journal of the International Hydrological Programme for Latin America and Caribbean, UNESCO 2009, Vol 1, 1:63-71.

Abstract

The aim of this study was to determine the number of Cryptosporidium sp oocysts and Giardia sp cysts present in the surface water and groundwater used by the population of the town of Cayes (Haiti). Volumes from 3 to 200 litres of water from different sources were taken from 15 sites around the town (bathing water and household waste water, spring water, boreholes, water supply, domestic wells), filtered by filter cartridges and stored at 4°C until treatment. The oocysts and cysts were isolated by using an immunomagnetic method and counted under fluorescence microscopy after marking with a monoclonal antibody. Of the 15 water samples analysed, 8 (53%) contained Cryptosporidium oocysts and/or Giardia cysts. The number of Cryptosporidium sp oocysts detected varied from 5 to 100 with an average of 29 oocysts for 100 litres of filtered water; for the Giardia cysts the number ranged from 5 to 960 with an average of 277 cysts per 100 litres of filtered water. This study shows that the surface water and groundwater of the town of Cayes are contaminated by pollution of faecal origin and thus constitute a potential source of biological risk for the health of the population exposed.

Evens Emmanuel, Marie Gisèle Pierre, Yves Perrodin. Groundwater contamination by microbiological and chemical substances released from hospital wastewater: health risk assessment for drinking water consumers. Environment International 35 (2009) 718–726

Abstract

Contamination of natural aquatic ecosystems by hospital wastewater is a major environmental and human health issue. Disinfectants, pharmaceuticals, radionuclides and solvents are widely used in hospitals for medical purposes and research. After application, some of these substances combine with hospital effluents and, in industrialised countries, reach the municipal sewage network. In certain developing countries, hospitals usually discharge their wastewater into septic tanks equipped with diffusion wells. The discharge of chemical compounds from hospital activities into the natural environment can lead to the pollution of water resources and risks for human health. The aim of this article is to present: (i) the steps of a procedure intended to evaluate risks to human health linked to hospital effluents discharged into a septic tank equipped with a diffusion well; and (ii) the results of its application on the effluents of a hospital in Port-au-Prince. The procedure is based on a scenario that describes the discharge of hospital effluents, via septic tanks, into a karstic formation where water resources are used for human consumption. COD, Chloroform, dichlomethane, dibromochloromethane, dichlorobromomethane and bromoform contents were measured. Furthermore, the presence of heavy metals (chrome, nickel and lead) and faecal coliforms were studied. Maximum concentrations were 700 NPP/100 ml for faecal coliforms and 112 mg/L for COD. A risk of infection of 10-5 infection per year was calculated. Major chemical risks, particularly for children, relating to Pb(II), Cr(III), Cr(VI) and Ni(II) contained in the ground water were also characterised. Certain aspects of the scenario studied require improvement, especially those relating to the characterisation of drugs in groundwater and the detection of other microbiological indicators such as protozoa, enterococcus and viruses.

Evens Emmanuel, Joaneson Lacour, Ketty Balthazard-Accou, Osnick Joseph. Ecological hazard assessment of heavy metals and nutrients contained in urban effluents on bay ecosystems of Port-au-Prince (Haiti). AQUA-LAC, Journal of the International Hydrological Programme for Latin America and Caribbean, UNESCO 2009, Vol 1, 1:18-28.

Abstract

The bay of Port-au-Prince is a body of water into which flow rainwater and untreated urban wastewater from residential zones, and commercial and industrial activities. The presence of pollutants in untreated urban wastewater constitutes a hazard to aquatic organisms and can greatly affect the balance of the bay's ecosystem. The aim of this study was: (i) to implement an environmental hazard assessment framework for untreated urban wastewater; (ii) and to apply it to urban wastewater discharged by an open channel of the combined sewage system of Port-au-Prince. COD, heavy metals, NO3-, PO43- and dissolved oxygen were chosen as the main parameters for this assessment. 69 samples were collected from the experimental site from September 2003 to May 2005. High concentrations of NO3- (22.88 mg/L), PO43- (62 mg/L) and COD (1500 mg/L) were detected. These concentrations are much higher than the threshold values set by the regulations relating to wastewater discharges into natural environments. Metals in solution were mostly below the detection limit of the apparatus used. DO contents were very low, highlighting heavy organic load, combined with a low dissolution rate in the water of the channel before discharge into the sea. In view to enriching these initial results, it is now necessary to carry out a thorough environmental hazard assessment of the wastewater channel discharge in Port-au-Prince bay and, in particular, establish the proportions of organic pollutants in the discharge by implementing ecotoxicity tests. It appears necessary in future to perform the physicochemical and ecotoxicological characterization of the contaminated sediments in the channel, in order to develop ecohydrological tools for managing the ecological hazards and risks related to effects of the channel’s total pollution on the environment of Port-au-Prince.

Evens Emmanuel, Ruth Angerville, Osnick Joseph, Yves Perrodin. Human health risk assessment of lead in drinking water: A case study from Port-au-Prince Haiti. International Journal of Environment and Pollution, 2007, Vol. 31, Nos. 3/4, 280-291. 

Abstract

In Latin America and the Caribbean (LAC), human intoxication by lead is considered as an important public health issue. In Port-au-Prince, concentrations of lead ranging from 40 μg/L to 90 μg/L, greater than the threshold value (10 μg/L) for drinking water, were measured in groundwater and drinking water. This study assesses human health risks generated by exposure to lead in the Port-au-Prince water supply. Two sampling campaigns were performed between April 2004 and December 2004 on different structures of the public water supply. A significant lead concentration of 250 μg/L, greater than the threshold value, had been detected in a water tank. Risk of deterioration of the psychological development of children exposed to these waters was calculated. These results require monitoring in order to control the risk to human health by lead in the drinking water of Port-au-Prince.

Evens Emmanuel, Ketty Balthazard-Accou, Osnick Joseph. Impact of urban wastewater on the biodiversity of aquatic ecosystems. In.: Mattheus Goosen, Eddie Laboy, Fred Schaffner and Ahmed Abdelhadi (eds). Environmental Management, Sustainable Development and Human Health, in press, Taylor and Francis, 2009, pp. 399-424.

Summary