Biosorption Potential of the Microchlorophyte Chlorella vulgaris for Some Pesticides

摘要

Nowadays, pollution of either surface or ground water with pesticides is considered as one of the greatest challenges facing Humanity and being a national consideration in Egypt. Agricultural activities are the point source of pesticides that polluting water bodies. The present study investigated the potentiality of Chlorella vulgaris for bioremoval of pesticides mixture of 0.1 mg/mL for each component (Atrazine, Molinate, Simazine, Isoproturon, Propanil, Carbofuran, Dimethoate, Pendimethalin, Metoalcholar, Pyriproxin) either as free cells or immobilized in alginate. Two main experiments were conducted including short- term study having 60 min contact time using fresh free and lyophilized cells and other long-term study having five days incubation period using free and immobilized cells. In the short-term study, the presence of living cells led to bioremoval percentage ranged from 86 to 89 and the lyophilized algal biomass achieved bioremoval ranged from 96% to 99%. In long-term study, the presence of growing algae resulted in pesticides bioremoval ranged from 87% to 96.5%. The main mechanism behind the removal of pesticides in water phase is proposed to be biosorption onto the algal cells. This conclusion is based on the short duration required for removal to occur. The obtained results encourage using microalgae in bioremediation of pesticides polluted water.