Effect of water soluble fraction (WSF)‎ and the oil-in water dispersions ( OWD )‎ of crude oil on the survival rate of crab Sesarma boulengeri from Hamdan canal a branch of Shatt al-Arab. Iraq

Abstract EN

The present study includes toxicity experiments carried out under laboratory conditions for ( 24 , 48 , 72 , 96 and 120 ) hours period by using renewal toxicity test system to determine the comparison of crude oils , dispersant mixtures and the water – soluble fraction to crab Sesarma boulengeri male and female net weight (2.655 ±0.5) gm which is found in Hamdan canal , a branch from Shatt Al _Arab River .

The median lethal time (LT50) has been recorded for each concentration and median lethal concentration (LC50) has also been recorded within (120) hours of exposure to concentrations of ( 2.5 , 5 , 10 and 20 ) ml / l crude oil .

The toxicity experiments show that the dispersant mixture water soluble fraction ( WSF ) vary widely in their toxicity and accumulation of petroleum hydrocarbons to the specimen tested and slightly less toxic to oil – in water dispersions ( OWD ) .

The mortalities increased with the increase of the concentrations and with the increase of time .

The female tend to accumulate petroleum hydrocarbons slightly more than the male , and that the individuals had an ability to dispose large amounts of oil pollutants after their recovery in clean water