Bioassay testing the toxicity of nano-structure polymer (PAMAM G2) as coagulant aid in water treatment

Abstract

Poly (amido amine) generation 2.0 (PAMAM G2) has a tree-like structure having different applications and properties, among them is trapping tiny flocks and improving the procedure of coagulation. In this study, the toxicity effect of PAMAM G2 nanodendrimer as a coagulant aid was surveyed through bioassay testing for the first time. For this purpose, PAMAM G2 as a coagulant aid was applied at different doses (0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 mg L -1), accompanied by ferric chloride as coagulant in jar test. Then, the toxicity of water extracted from coagulation process and one sample without PAMAM G2 as testament were assessed. In order to measure the acute toxicity, bioassay experiment with Daphnia magna was used. It was cultured in specific medium for mass culture. Then, six young generated juveniles plus one as testament were added to each vessel. The bioassay test was performed for 48 h during which each sample was taken and evaluated at time interval of 2, 4, 8, 12, 24 and 48 h. The results showed that the usage of PAMAM G2 as coagulant aid would not lead into toxicity in water.