ZOU, E.*; STUEBEN, B.; Nicholls State University, Thibodaux, LA: Acute exposure to naphthalene reduces oxyregulating capacity of the brown shrimp, Penaeus aztecus, subjected to progressive hypoxia

The brown shrimp, Penaeus aztecus, in the northern Gulf of Mexico is faced with dual stresses of environmental hypoxia, which occurs as a result of nutrients input from the Mississippi river, and the pollution of polycyclic aromatic hydrocarbons (PAHs) from the activities of petroleum and gas production on the continental shelf of the northern Gulf of Mexico. This study investigated the modulation of oxyregulating capacity of Penaeus aztecus subjected to progressive hypoxia by a representative PAH, naphthalene. We found that Penaeus aztecus is an oxyregulator with a critical oxygen concentration of 2.53 mg/l at 19 � 21 �C. Acute exposure to naphthalene at 2.0 mg/l significantly reduced the oxyregulating capacity by 112%. This is the first report on the alteration of an aquatic animal�s oxyregulating capacity by a PAH.