Risk evaluation for mollusk consumption polluted with cadmium, chromium and lead

Abstract

Pectinids accumulate metals at higher levels in comparison to other mollusks. This constitutes a possible risk for people that consume them since it has been detected that concentrations of cadmium, chromium and lead in these organisms exceed the maximum limit established by the Mexican NOM (Norma Oficial Mexicana 031-SSA1993). The objective of this work was to determine the concentrations of those metals in tissues of Catarine clams and to evaluate the possible risk that implicates their consumption calculating the minimal secure ration (per day). Samples were collected during the summer and winter seasons of 1998, 1999 and 2000, from the mollusk farm of UABCS (Universidad Autónoma de Baja California Sur, México). The quantification of the elements was carried out by means of atomic absorption technique in flame. The average concentrations of Cd, Cr and Pb ± SD (standard deviation) registered in the scallops ranged from 1.76 ± 1.23, 0.288 ± 0.228 to 3.34 ± 1.09 µg/g (d.w., dry weight), respectively. The season and year that showed the highest concentrations was during the summer (July 1998). The safety portions of scallops (g) calculated for children, women and men (per day) and weight of consumers were: For children of 18 and 30 kg, portions of 1.50 and 2.50 g (w.w., wet weight); for women of 50, 60 and 70 kg, portions of 97.09, 116.50 and 135.92 g (w.w.), respectively. For men of 70, 80, 90 and 100 kg, 135.92, 155.33, 174.75 and 194.17 g (w.w.) of clams. The consumption of higher rations might imply a health risk.