Heavy Metals in Black Crabs in the Atlantic Coast (Tenerife, Spain) – Human Risk Assessment

Abstract

Crustaceans are considered to be a staple ingredient in a healthy balanced diet. This work determines the cadmium (Cd) and lead (Pb) content in the soft tissue (muscle) and the exoskeleton of 60 samples of black crabs from different areas of the coast of Tenerife (Canary Islands, Spain) by graphite furnace atomic absorption spectrophotometry. Average concentrations of Cd found in the soft tissue and the exoskeleton were 1.148 and 1.089 mg/kg, respectively. In the case of Pb, these levels were 4.736 and 13.92 mg/kg. People consume muscle tissue more than any other tissue. An average weekly intake of 10.36 g/person per week of black crab muscle provides an estimated weekly intake of 11.89 μg/week of Cd and its contribution to the tolerable weekly intake (TWI) is 6.79%. In the case of Pb, the estimated daily intake is 1.13 μg/week and its contribution to the provisional tolerable weekly intake (PTWI) is 0.06%. The values of the estimated weekly intake of Cd and Pb were lower than the TWI. In conclusion, there is no toxicological risk from the weekly consumption of crabs if we use the estimated daily intake of crab data published by the Spanish Food Safety Agency. However, both metals exceed the maximum levels permitted by the European Regulation.