IHEM   20887
INSTITUTO DE HISTOLOGIA Y EMBRIOLOGIA DE MENDOZA DR. MARIO H. BURGOS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Accumulation and detoxification of heavy metals in the sentinel organism Pomacea canaliculata
Autor/es:
CAMPOY DÏAZ, ALEJANDRA D; VEGA ISRAEL A.
Lugar:
Tucumán
Reunión:
Congreso; Tercer Reunión Conjunta de Sociedades de Biología; 2015
Institución organizadora:
Sociedades de Biología
Resumen:
Model organisms with the ability to produce a specific and measurable response to the exposure to xenobiotics can be used as a sentinel of water?s contamination. These organisms can help to resolve some limitations of traditional methods since these cannot detect emissions of xenobiotics released in irregular form and are quickly diluted in large water?s bodies. Pomacea canaliculata is a freshwater mollusc widely distributed around the world and it lodges a prokaryotic organism within its digestive gland?s cells. The endosymbiont has two morphological types (identified as C and K) and they are released regularly in huge quantities from the digestive gland to the intestine. We have shown that the kidney and digestive gland (and the endosymbionts contained therein) of this apple snail are the main places of incorporation of mercury, arsenic and uranium from the water. Here, we studied the time retention of each metal (at four times; 7, 14, 28 and 56 days post exposition) in tissues, endosymbionts, and faeces of P. canaliculata after a chronic exposure period (60 days) to sub-lethal doses (mercury = 2 µg/L; arsenic = 10 µg/L; uranium = 30 µg/L). The elements of these samples were measured by neutron activation. After the exposition to three metals, the ´memory´ was retained in the kidney, digestive gland and endosymbionts of P. canaliculata. Only the morfotype K of the endosymbiont exhibited a significant decrease of mercury concentration at the day 56 post-exposition. Also, elemental concentrations in faeces decreased gradually after the exposition indicating that the metals were eliminated through of the endosymbiont. We suggest that this symbiotic association might be useful for biomonitoring of freshwater ecosystems.