The concentrations of heavy metals in the bivalve molluscs Anadara similis and A. tuberculosa are determined. The specimens were collected at 2 km from the mouth of Estero Huaylá, El Oro Province, Ecuador, in November 2013. The length and weight of each species were determined in the laboratory, with two length ranges being established for A. similis and four for A. tuberculosa. The meat of the organisms was extracted, washed and dried in an oven at 60 ° C for 72 h, then digested w...