Phosphorus amendment competitively prevents chromium uptake and mitigates its toxicity in Spinacea oleracea L.

In this study, we assessed the role of phosphorus in preventing chromium uptake by plants. Two-factor complete randomized pot experiment (5x5 pattern) was conducted hydroponically with Spinacea oleracea L. (spinach), for 28 days in green house. Five concentrations of Cr (2.0, 3.5, 5.0, 6.5 and 8.0 mM), each amended with five concentrations of phosphorus (25, 50, 75, 100 and 125 mM) were supplied. With the phosphorus amendment in the growth medium, accumulation of chromium decreased up to 55% in root and 50% in shoot tissues. A 1.8-fold enhancement in total chlorophyll and 2-fold increase in the biomass of root and shoot were observed due to phosphorus amendment. Levels of superoxide dismutase, catalase, peroxidase and malondialdehyde were reduced by 27, 11.7, 38.1 and 45.5% in root tissues; and 27, 17.4, 32.3 and 35.1%, in shoot tissues, respectively. In conclusion, the phosphorus amendment has been shown not only to moderate the Cr-toxicity in S. oleracea but also enrich chlorophyll content as well as the biomass.

Differential response of Tilapia guineensis fingerlings to inorganic fertilizer under various salinity regimes.

The influence of salinity on the response of the estuarine teleost, Tilapia guineensis fingerlings to acute toxic effects of inorganic nitrogen-phosphorus-potassium (NPK) (15: 15: 15) fertilizer was investigated using semi-static bioassay. The toxicity of NPK fertilizer was found to increase significantly with increase in the salinity level from 0.05 %. to 32.4 %o. The 96 hr LC50 value at salinity of 32.4 %o was 0.11 mg/l and was found to be significantly (p < 0.05) higher than the toxicity values at any other salinity level of media evaluated. The implication of the findings is that pollution control standards and/or safe limits for brackish water ecosystem should consider variations in salinity regimes for greater relevance and reliability.

Utilizacion del interferon en necrosis hepatica por paraquat y fosoforo amarillo: evaluacion experimental / Use of interferon in hepatic necrosis produced by paraquat and yellow phosphorus: eperimental evaluation

El Paraquat y el Fósforo Amarillo son sustancias tóxicas que al ser ingeridas accidentalmente o con intenciones suicidas, producen una alta tasa de morbimortalidad usualmente asociada a una necrosis hepática. Se realizó un estudio para evaluar el efecto protector del interferón en ratas intoxicadas con estas dos sustancias. Las ratas fueron divididas en grupos que recibieron solamente el tóxico (Paraquat y Fósforo Amarillo) y otro grupo recibió el tóxico y el interferón. Los resultados mostraron una alta proporción de supervivencia en los grupos tratados con interferón, el mismo fue mayor del 20 por ciento. Además, los hallazgos histopatológicos encontrados demostraron un efecto protector hepático que fue mayor del 90 por ciento en las ratas que recibieron el interferón. Clínicamente, el Paraquat fue más tóxico que el Fósforo Amarillo. Este resultado experimental favorable obtenido con el uso del interferón necesitará mayor investigación en el futuro para evaluar su posible utilización en el tratamiento de este tipo de intoxicaciones.