title: Apple snails and their endosymbionts bioconcentrate heavy metals and uranium from contaminated drinking water.
abstract: OBJECTIVE
  The differential ability of apple snail tissues, endosymbionts, and eggs to bioaccumulate several metals (Sb, As, Ba, Br, Zn, Cr, Fe, Hg, Se, and U) was investigated.
  
  
  METHODS
  Metal concentrations were determined by neutron activation analysis in several tissues, endosymbionts, and eggs from mature apple snails cultured in either drinking water or reconstituted water (prepared with American Society for Testing and Materials type I water).
  
  
  RESULTS
  The highest bioconcentration factors (BCFs) in the midgut gland were found for Ba, Zn, Se, As, U, Br, and Hg (in decreasing order), while the highest in the kidney were for Ba, Br, and Hg. The foot showed the highest BCFs for Ba, Hg, Br, and Se (in decreasing order). Calcified tissues (uterus, shell) and eggs showed low BCFs, except for Ba. Both C corpuscles and gland tissue showed statistically higher BCFs than K corpuscles for Ba, Fe, U, Br, and Sb. The concentration of most of the studied elements was significantly lower in tissues and endosymbionts obtained from snails cultured in reconstituted water instead of drinking water. Snails cultured in reconstituted water and then exposed or not to Hg, As, and U (at the maximum contaminant level allowed by the US Environmental Protection Agency) also resulted in high levels accumulated in midgut gland, endosymbionts and kidney.
  
  
  CONCLUSIONS
  Our findings suggest that the midgut gland (and the symbionts contained therein), the kidney, and the foot of Pomacea canaliculata may be useful bioindicators of Hg, As and U pollution in freshwater bodies and that the unrestricted use of ampullariid snails as human and animal food must be considered with caution.
authors.affiliation: Laboratorio de Fisiología (IHEM-CONICET), and Departamento de Morfología y Fisiología, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Casilla de Correo 33, 5500 Mendoza, Argentina. israel.vega7@gmail.com
authors.forename: Israel A
authors.initials: IA
authors.lastname: Vega
authors.forename: María A
authors.initials: MA
authors.lastname: Arribére
authors.forename: Andrea V
authors.initials: AV
authors.lastname: Almonacid
authors.forename: Sergio
authors.initials: S
authors.lastname: Ribeiro Guevara
authors.forename: Alfredo
authors.initials: A
authors.lastname: Castro-Vazquez
mesh_terms: D000818:Animals; D060766:Drinking Water / Q000737:chemistry*; D005260:Female; D007668:Kidney / Q000737:chemistry; D019216:Metals, Heavy / Q000032:analysis / Q000378:metabolism*; D009501:Neutron Activation Analysis; D012908:Snails / Q000378:metabolism*; D014501:Uranium / Q000032:analysis / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000378:metabolism*; D018508:Water Purification / Q000379:methods*; D060753:Water Quality
chemical_list: D060766:Drinking Water; D019216:Metals, Heavy; D014874:Water Pollutants, Chemical; D014501:Uranium