Development of sediment toxicity test with tropical peneid shrimps

A methodology to test the toxicity of marine and estuarine sediments was de veloped using postlarval organisms of the marine shrimp Penaeus schmitti an d P. paulensis. The tests were conducted in aquariums with a water feedback system and a sediment layer of 2 cm. The postlarvae exposure time to the s ediments was 10, 28, and 52 d. The tested sediments were collected in conta minated sites of Guanabara and Sepetiba Bays and at the reference site of I lha Grande inlet in Rio de Janerio, Brazil. The toxicity of the sediments w as evidenced with exposures of 28 d or longer. The sediment from Saco do En genho (Sepetiba Bay) was the most toxic, affecting the survival of both P. schmitti and P. paulensis. The sediment from Guanabara Bay was toxic to P. schmitti, affecting its survival after 28 d of exposure.