Toxicological Impact And Ecological Implications Of Effluent And Inorganic Mercury On Environment & A Crop Plant.

The effluent and solid waste of the Chlor-alkali industry contained significant amount of mercury. The effluent after joining the Rushikulya River significantly changes the physico-chemical properties of river water. The river water which is used for irrigation contained significant amount of mercury. The mercury concentration significantly varied in all the 5 stations of the effluent canal. The sediments collected from the effluent canal were dumped nearby. It was observed that the solid waste contained significant amount of mercury much more than prescribed limit. The lechate and washings enter into the river during rainy season increasing the mercury level in the river water. This river water was used to irrigate the crop fields at down stream. Residual mercury was found in effluent mixed river water used for irrigation. Mercury was also found in the crop fields where contaminated water was used for irrigation. Field study indicated that most of the crops and vegetables cultivated in these contaminated crop fields contained mercury. Most of the mercury available was in the inorganic form, very less in organic form and elemental mercury was also available. Elemental mercury is converted to inorganic and organic mercury by natural transformation. All the three types of mercury were found in the crop fields. It was planned to study the impact inorganic mercury as mercuric chloride on the seed biology of a crop plant. The seed germination and seedling establishment decreased significantly with the increase in mercury concentration, when compared to the respective control values. The pigments like total chlorophyll, total pheophytin and carotenoid content significantly decreased in exposed seedling leaves compared to control seedling leaves of rice crop seedlings. Mercury is highly toxic and should not be released into the environment as the toxicant severely affects the environment and the crop plant.