التأثير السمي لبعض المبيدات الفوسفورية العضوية في النوع Arctodiaptomus (Rha bdodiaptomus)‎ Bacillifer (Calanoidae, Copepoda)‎

Abstract EN

The ever increasing use of pesticides in agriculture has meant that surface water, its fauna and floura are increasingly exposed to pollution danger.

Hence, the LC50 value is considered as a determining factor to the feasibility of using water in agriculture and fisheries and the possibility of treating such water to make it potable in some low resource area.

LC50 for the organo-phosphoric pesticides: malation, dichlorophos and chloropyrifos-methyl on Arctodiaptomus (Rhabdodiaptomus) Bacillifer (Calanoidae,Copepoda) was determined.

Also, the long lasting poisonous impact of the former pesticides on protein mass of A.bacillifer was studied.

LC50 for malation, dichlorophos and chlorpyrifos-methyl was (0.1 µg/l), (20µg/l) and (1 µg/l), respectively.

Protein concentration was lower in animals exposed to any of the tested pesticides compared to the control.

Generally, protein concentration correlated inversely with the sublethal doses for all pesticides tested.

Thus, at a concentration of (0.025 µg/l) and a 4 day exposure-period protein concentration was (0.0026 g/dl),(0.00278 g/dl) and (0.0024 g/dl) for chlorpyrifos-methyl, malation and dichlorophos, respectively compared to (0.0048 g/dl) for control treatment.

Whereas, for an exposure period of 6 day to the same concentration (0.025 µg/l) protein concentration decreased to (0.0018 g/dl) for malation and was zero for chlorpyrifos-methyl and dichlorophos.

When exposed to a lower concentration of pesticides (0.002 µg/l) for an exposure period of 6 days, protein concentration decreased to (0.004 g/dl), (0.002 g/dl) and (0 g/dl), respectively compared to (0.0048 g/dl) for the control.