title: Influence of ionic strength and soil characteristics on the behavior of Cryptosporidium oocysts in saturated porous media.
abstract: The physico-chemical behavior of Cryptosporidium oocysts was investigated during their transfer through an alluvial formation from Les Cayes (Haiti) via batch tests. Five approximately 3 kg soil samples were collected and combined prior to batch tests from the alluvial formations. The experiments were carried out at soil pH by equilibrating different ranges of pure oocysts concentrations and soil samples with 3mM CaCl2 and 1mM NaBr as electrolyte. We used the Debye-Hückel equation describing ion activity in a solution for a given ionic strength. The equilibrium adsorption mechanism is used to enumerate the oocysts in the soil. The results suggest that the oocysts behavior in porous media depends on soil characteristics such as soil pH, the nature of the mineral and organic constituents of the soil and the ionic strength and activities in solution. These results show that a total transfer in batch containing NaBr solutions against a partial one in batch containing CaCl2 solutions depends on the oocysts media concentration. To confirm the oocysts number retained in soil, confocal microscopy was successfully used and the images demonstrate that the majority of oocysts were retained at the range of concentrations tested. The findings from this study demonstrated that the retention of C. Parvum in soils may be influenced by chemical conditions and soils characteristics, which are important for groundwater risk assessment.
authors.affiliation: Université Quisqueya - Laboratoire de Qualité de l'Eau de l'Environnement, 218 Ave Jean Paul II, Haut de Turgeau, Port-au-Prince, Haiti; Parasitology Laboratory - Mycology, Amiens University Hospital, Avenue Laënnec, 80054 Amiens, France. Electronic address: kettybal@gmail.com.
authors.forename: Ketty
authors.initials: K
authors.lastname: Balthazard-Accou
authors.affiliation: Université Quisqueya - Laboratoire de Qualité de l'Eau de l'Environnement, 218 Ave Jean Paul II, Haut de Turgeau, Port-au-Prince, Haiti.
authors.forename: Urbain
authors.initials: U
authors.lastname: Fifi
authors.affiliation: Parasitology Laboratory - Mycology, Amiens University Hospital, Avenue Laënnec, 80054 Amiens, France; University of Picardie Jules Verne, URF Pharmacie, Equipe théra, Laboratoire des Glucides-FRE-CNRS 3517, 1, rue des Louvels, 80037 Amiens Cedex 1 Amiens, France.
authors.forename: Patrice
authors.initials: P
authors.lastname: Agnamey
authors.affiliation: Université d'État d'Haïti - Unité de Recherche en Environnement, Faculté des Sciences, 270 rue Mgr Guilloux, Port-au-Prince, Haiti.
authors.forename: Justin André
authors.initials: JA
authors.lastname: Casimir
authors.affiliation: Institut de Recherche pour le Développement (IRD), UMR 198, Centre de Hann, Dakar, Senegal.
authors.forename: Philippe
authors.initials: P
authors.lastname: Brasseur
authors.affiliation: Université Quisqueya - Laboratoire de Qualité de l'Eau de l'Environnement, 218 Ave Jean Paul II, Haut de Turgeau, Port-au-Prince, Haiti.
authors.forename: Evens
authors.initials: E
authors.lastname: Emmanuel
mesh_terms: D000818:Animals; D016785:Cryptosporidium parvum / Q000254:growth & development*; D033661:Oocysts / Q000254:growth & development*; D009994:Osmolar Concentration; D016062:Porosity; D012987:Soil / Q000737:chemistry* / Q000469:parasitology*
chemical_list: D012987:Soil
keywords: Adsorption; Batch tests; Cryptosporidium oocyst; Groundwater; Soil; Transfer