Toxic Effects of Linear Alkylbenzene Sulfonate on the Tiger Prawn, Penaeus monodon

The toxic effects of linear alkybenzene sulfonate (LAS) on the larvae and juveniles of tiger prawn Penaeus monodon were tested. The 24-hr LC50 values of LAS were 0.06, 0.10, and 3.11 ppm for the zoea 2nd substage, mysis 2nd substage (M2), and postlarva 12th substage (PL 12) of the tiger prawn, respectively. The 48-hr LC50 values of LAS were 0.07, 1.03, and 4.36 ppm for M2, PL12, and postlarva 15th substage of the tiger prawn, respectively. The hepatopancreatic glutathione (GSH) in juvenile tiger prawn was obviously depleted when LAS concentration was over 1.0 ppm. The hepatopancreatic GSH content of tiger prawn exposed to solutions of greater than 1.0 ppm LAS was difficult to raise to normal levels, even after the tiger prawns were switched to an LAS-free solution. The activity of malate dehydrogenase in the serum of juvenile tiger prawns exposed to 10.0 ppm LAS solution was significantly increased.