Year: 2017, Issue: December
Eco-toxicological interaction studies on leached chemicals of red mud waste of alumina industry and a pesticide on the seed biology of a crop plant under laboratory controlled conditions.
Swarnalata Pattanaik, A. Leelaveni and A. K. Panigrahi
Alumina industry, Red mud waste, Red mud waste extract, Pestiocide, Seed germination, Pigments.
The red mud waste of the Alumina industry causes environmental contamination in the Damojodi area at Koraput district. The leached chemicals from the red mud pond enter into neighboring crop fields and cause severe damage to rice crop. The red mud waste was brought to the laboratory in plastic containers and kept in refrigerator for studies. The red mud waste was air dried and powdered. The dried red mud waste was taken and an extract was prepared in the laboratory. Graded series of concentrations of the red mud waste extract were prepared along with soil and cow dung mixture (3:1) and germination studies were conducted to find out lethal concentration values. During germination a regularly used pesticide was also applied at a recommended dose to see the impact and interaction both the toxicants. With the increase in red mud waste concentration, the germination of seeds decreased significantly. The lethal concentration values increased and the percent survival decreased with the increase in waste concentration. With the application of the RMW extract, along with the recommended dose of a pesticide most of the parameters showed a declining trend in the exposed seedlings when compared to control seedlings. No stimulation or better growth was observed at sub-lethal dose of both the toxicants. The mean root and shoot length decreased in all exposed seedlings. No stimulation was marked. The root and shoot fresh weight and dry weight decreased with the increase in toxicant concentration. The total chlorophyll content decreased significantly from 1.19 mg/gm (Control) to 1.01 mg/ gm at 1.5 ppm RMWE concentration. which was the LC10 concentration and it decreased significantly to 0.11 mg/gm at 5 ppm of the RMW extract at the highest select concentration. Total pjhaeophytin and total carotene significantly decreased with the increase in RMWE concentration. The RMWE exposed leaves curled and browning of the tips were noticed in the exposed seedlings. Browning and swellings of the roots were marked in all the RMWE exposed seedlings when compared to control seedlings. Shoot was not seen in the exposed seedlings at higher concentrations, however root was present. The study on seed biology indicated that the red mud waste dumped by the industry is deadly toxic and if released accidentally even into the environment, will cause environmental havoc.