The joint toxicity effects of Chlorpyrifos ethyl and Fenobucarb to Climbing perch (Anabas testudineus) from rice fields in the Mekong Delta, Vietnam
2016 (English)In: Environmental science and pollution research international, ISSN 0944-1344, E-ISSN 1614-7499Article in journal (Refereed) Epub ahead of print
Organophosphates (e.g. chlorpyrifos ethyl) and carbamates (e.g. fenobucarb), are commonly used to control a wide range of pests in rice fields of the Mekong Delta in Vietnam. This study assesses the combined effect of chlorpyrifos ethyl (CPF) and fenobucarb (F) on the brain acetylcholinesterase (AChE) activity in climbing perch fingerlings from rice fields in the Mekong Delta. It also investigates if Pyridine-2-aldoxime methiodide (2-PAM) can be used to re-activate cholinesterase that has been blocked by CPF and F. Three days after spraying, the water concentrations of both insecticides decreased quickly below the detection levels. However the brain AChE activity in fish was inhibited for more than seven days. The results indicate a quicker but less prolonged inhibition of the brain AChE activity by the mixture than by only CPF. The inhibition levels were above 70% only during the first 48 hours, which could explain why all fish survived. 2-PAM resulted in a significant re-activation of the cholinesterase blocked by a combination of CPF and F, and it is proposed that the re-activation by 2-PAM could provide a way to assess the AChE inhibition level in organisms, when no unexposed individuals are available as controls. The results indicate that current use of CPF and F in rice farming in the Mekong Delta is likely to cause negative effects on non-target organisms. Many of these effects may be sub-lethal, and there is a need to develop relevant bio-markers, that are relevant, cheap and easy to apply under tropical conditions in developing countries.
Place, publisher, year, edition, pages
Anabas testudineus, Chlorpyrifos ethyl, Fenobucarb, Mixture, Acetylcholinesterase, Mekong Delta
Research subject Physical Geography
IdentifiersURN: urn:nbn:se:su:diva-128415DOI: 10.1007/s11356-016-6980-yOAI: oai:DiVA.org:su-128415DiVA: diva2:914869
ProjectsSwedish International Development Cooperation Agency (Sida) (Ref. No. AKT2010-010) through the Partner Driven Cooperation (PDC) project “Managing Ecosystem Services for Sustainable Aquaculture Development.