Saxitoxin monitoring in three species of Florida puffer fish

Beginning in April 2002, three species of Florida puffer fish from around the state of Florida, USA were monitored for the presence of saxitoxin (STX). In total, 873 southern (Sphoeroides nephelus),171 checkered (S. testudineus), and 53 bandtail (S. spengleri) puffer fish were collected between 2002 and 2006 from eight regions: Jacksonville, the Indian River Lagoon, Tequesta, the Florida Keys, Charlotte Harbor, Tampa Bay, Cedar Key, and Apalachicola. Emphasis was placed on collecting specimens from the Indian River Lagoon (IRL), where recreational harvesting of puffer fish led to 28 cases of saxitoxin puffer fish poisoning (SPFP) between January 2002 and May 2004. Southern puffer fish from the northern IRL routinely contained the highest concentrations of STX, with average levels in the skin of 1787 mu g STXequiv./100 g tissue. Elevated concentrations were also found in the muscle (1102 mu g STXequiv./100 g), gut contents (539 mu g STXequiv./100 g), gonads (654 mu g STXequiv./100 g), and liver (214 mu g STXequiv./100 g). Lower, yet significant (above the action limit of 80 mu g STXequiv./100 g tissue), concentrations of STX were also detected in the skin (599 mu g STXequiv./100 g), muscle (233 mu g STXequiv./100 g), gut contents (197 mu g STXequiv./100 g), and gonads (239 mu g STXequiv./100 g) of southern puffer fish from Tequesta in the southern IRL, as well as in the gonads (122 mu g STXequiv./100 g) of Jacksonville southern puffer fish and the skin (265 mu g STXequiv./100 g) of Tampa Bay southern puffer fish. STX concentrations above the action limit were also found in the skin of bandtail puffer fish from the IRL (620 mu g STXequiv./100 g), Tequesta (374 mu g STXequiv./100 g), and the Florida Keys (230 mu g STXequiv./100 g). Checkered puffer fish collected from the IRL, Tequesta, and the Florida Keys on average were nontoxic, containing STX levels below the action limit in all tissues. (C) 2008 Elsevier B.V. All rights reserved.