Community-level effects of a neonicotinoid pesticide on the metabolism of freshwater microorganisms
Cera, A., Kodama, S., Faulks, L. K. and Hakoyama, H.This study provides an ecotoxicological assessment of the effects of the neonicotinoid dinotefuran on freshwater microorganisms. Epilithic biofilm was sampled from a small stream and exposed to dinotefuran for 14 days in Biolog EcoPlates. In general, we found that a concentration of 0.100 mg l-1 of dinotefuran induced the microorganism community to catabolise carbon sources faster. However, catabolic activity varied depending on the type of carbon source. Catabolism increased for Putrescine (+4673 %), Serine (+376 %), Galacturonic Acid (+206 %), Pyruvic Acid Methyl Ester (+177 %), and Gamma Amino Butyric Acid (+113 %); and decreased for Arginine (-59 %), Asparagine (-26 %), and Mannitol (-21 %). This is the first study in which EcoPlates have been used to investigate the effects of dinotefuran on freshwater epilithic biofilm at an environmentally realistic concentration.
Key Words: Pesticide Periphyton Freshwater Ecotoxicology Metabolism Microorganism