Effects of insecticide (dimethyl 2,2,2-trichloro-1-hydroxyethylphosphonate) on an aquatic microcosm

Abstract

In this study, the effects of insecticide dimethyl-1,1,1-trichloro-1-hydroxyethylphosphonate (DEP), which is employed in large quantities and discharged into rivers and lakes were examined on the population growth and dynamics in a microcosm system which included producer, Chlorella sp. Tolypothrix sp., consumer Cyclidium glaucoma, Lecane sp. Philodina sp. and Aeolosoma hemprichi, decomposer bacteria. DEP was found to significantly affect bacterial growth in a concentration-dependent manner. Data suggest that DEP exposure alters microcosm dynamics and potentially the ecosystem.

Keywords:

• DEP
• Environmental Pollutants
• Microcosm

Acknowledgements

This research was supported by the JISTEC (Japan International Science and Technology Exchange Center). Dr Wui was STA fellow before JSPS fellow in JISTEC from 2002 to 2003. The Science and Technology Agency (STA), an administrative organ of the Japanese government, established the STA Fellowship Program in 1988. Since October 1 1989, the program has been managed by the Japan Science and Technology Corporation ( JST), a statutory organization under the supervision of STA, in cooperation with the Japan International Science and Technology Exchange Center ( JISTEC). Logistic support to foreign researchers staying in Japan in the programs of JSPS Invitation Fellowships for Research in Japan and JSPS (Japan Society for the Promotion of Science Fellows) Postdoctoral Fellowship for Foreign Researchers.