The density difference between the cell body and the surrounding
medium causes sedimentation of the cell contents which results in
The NOEC and EC50 values obtained in the present study varied
for different parameters of E. gracilis. The lowest NOEC values were
obtained for velocity followed by chlorophyll a and carotenoids
after 24 and 72 h exposure. Therefore, these parameters can be
used as sensitive end points for toxicity assessment of Ariel towards
Euglena. No EC50 and NOEC are available for the same detergent
for comparison purposes except those published by Markina
and Aizdaicher (2007), Markina and Aizdaycher, 2010)