Trophic distribution of Cd, Pb, and Zn in a food web from Altata-Ensenada del Pabellón Subtropical Lagoon, SE Gulf of California.

The aim of the work was to obtain a comparative view of the trophic distribution of Cd, Pb, and Zn in different organisms of the food web (from primary producers to top predators), considering representative species in Altata-Ensenada del Pabellón subtropical lagoon (SE Gulf of California). The study provides the first quantitative information on the biotransference of Cd, Pb, and Zn in a moderately contaminated lagoon ecosystem. After examination of 31 trophic interactions, 20 cases resulted in transference factors (TF) > 1.0 for Cd, 14 cases for Pb, and 18 cases for Zn. For Cd, most of the TF > 1 were found mainly among the low trophic levels (15 of 20 links); for Pb, most of the TF > 1 were found mainly among the high trophic levels (11 of 14 links), and for Zn, most of the TF > 1 were found mainly among the low trophic levels (14 of 18 links). This can be interpreted as partial evidence of biomagnification of Cd, Pb, and Zn for the species involved.