Heavy Metals and Arsenic in Soft Tissues of the Gastropod Rapana Venosa (Valenciennes, 1846) Collected on a Mollusk Farm Off Sevastopol (Southwestern Crimea, Black Sea): Assessing Human Health Risk and Locating Regional Contamination Areas

The gastropod Rapana venosa is an edible mollusk suitable for biomonitoring of sea shelf contamination. In this work, the contents of five elements (Cu, Zn, As, Cd, Pb) in foot and in the rest of soft tissues of this mollusk were quantified, and the element contents in the edible foot were found below the maximum permissible levels set in several national and transnational regulations. The estimated daily intake of these elements and the hazard index indicated no likely risks to consumers' health, but the long-term cancer risks due to the arsenic intake were found significant. The arsenic and cadmium contents in soft tissues of this rapa whelk were among highest observed in the Black Sea region in the 2010s, and this suggests the specific arsenic and cadmium contamination of seawater off the southwestern Crimea. For the first time, this mollusk was shown to serve as a seawater contamination bioindicator at the regional level.