PROBIEN   20416
INSTITUTO DE INVESTIGACION Y DESARROLLO EN INGENIERIA DE PROCESOS, BIOTECNOLOGIA Y ENERGIAS ALTERNATIVAS
Unidad Ejecutora - UE
artículos
Título:
Response of biomarkers in amphibian larvae to in situ exposures in a fruit producing region at North Patagonia, Argentina
Autor/es:
ROSENBAUM E; DUBOSQ, L; SOLEÑO J; MONTAGNA M; FERRARI A; VENTURINO A
Revista:
ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY
Editorial:
SETAC PRESS
Referencias:
Año: 2012 vol. 31 p. 2311 - 2317
ISSN:
0730-7268
Resumen:
We evaluated
biomarker responses in caged larvae of the amphibian Rhinella arenarum in water channels during fruit production
season, and compared them with those elicited by a transient exposure to
azinphos methyl (AzM) (0.02-2 mg/L; 4 h), the main pesticide applied in the Alto
Valle region, Patagonia Argentina, taking into account the maximum environmental
concentration detected in superficial water (22.5 µg/L). The traditional biomarkers
of organophosphate exposure, acetylcholinesterase (AChE) and carboxylesterase
(CE), were inhibited in tadpoles after one week of exposure in channels potentially receiving pesticide drift, while the
antioxidant glutathione (GSH) and the detoxifying activity of GSH-S-transferase
(GST) were induced. In a two-week monitoring study, AChE activity was induced
in larvae exposed at the agricultural site, and CE showed an inhibition followed by the return
to control values suggesting an exposure-recovery episode. GSH levels were
first depleted and then surpassed control levels while GST activity was continuously
induced. These responses were mimicked in the laboratory by 2 mg/L AzM-pulse exposure,
which notably exceeds the expected environmental concentrations. The results
draw attention to the complexity of the responses under pesticide exposure,
strongly depending on exposure time-concentration and recovery periods among
other possible factors, and support the necessity of the integrated use of
biomarkers to assess
exposure episodes in agricultural areas.