Trace metals in target tissues and stomach contents of the top predator sailfish Istiophorus platypterus from the Eastern Pacific: concentrations and contrasting behavior of biomagnification.

Cadmium, lead, copper, and zinc were analyzed in the dorsal muscle, liver, gonad, and stomach contents of 67 sailfish, Istiophorus platypterus, from the Eastern Pacific. Muscle exhibited the following pattern (μg/g wet weight): Zn (15.05 ± 1.24) > Cu (0.461 ± 0.026) > Cd (0.434 ± 0.099) > Pb (0.025 ± 0.001); liver Zn (119.1 ± 7.6) > Cd (95.1 ± 11.0) > Cu (39.7 ± 2.6) > Pb (0.047 ± 0.004); and gonad Zn (96.8 ± 7.8) > Cd (2.16 ± 0.38) > Cu (2.08 ± 0.14) > Pb (0.033 ± 0.003). Significant (p < 0.05) correlations were observed between elements, length, and weight. I. platypterus feed mainly on fishes and cephalopods with variable concentrations (μg/g wet weight) of Cd (0.081-11.41), Pb (0.002-0.057), Cu (0.204-4.35), and Zn (3.23-86.6). Of the four analyzed elements, only Pb was biomagnified (BMF = 1.85). According to the regulatory limits, muscle exhibited Cd concentrations higher than the Official Mexican Standard, WHO, FDA (28 % of samples), and the European Union (40 %) regulations.