Persistent toxic substances in Mediterranean aquatic species

Area of Science:

• Environmental Chemistry
• Marine Biology
• Food Safety

Background:

• Fish and fishery products are significant dietary sources of persistent toxic substances (PTSs).
• Understanding PTS contamination in Mediterranean seafood is crucial for public health and environmental monitoring.
• Existing data on wild species contamination requires expansion for better risk assessment.

Purpose of the Study:

• To investigate PTS contamination in Italian Mediterranean fish and crustaceans.
• To evaluate the suitability of current regulatory limits for PTSs.
• To identify background concentration values and sources of variability in chemical body burdens.

Main Methods:

• Analysis of PTSs in twelve wild and two farmed fish species from Italian coastal waters.
• Comparison of contaminant concentrations with European Union regulatory limits and EFSA database values.
• Assessment of contamination variability based on species, food web position, and lifestyle.

Main Results:

• Contaminant concentrations in wild species were generally low, often below European ranges and well below maximum tolerable levels (excluding methyl mercury).
• Farmed fish exhibited significantly lower contamination levels than wild species.
• Absence of local contamination sources was suggested for wild species, yet regulatory levels could be exceeded due to food web dynamics.

Conclusions:

• A species-specific management approach for aquatic organism contamination is recommended over a general body burden assessment.
• Contamination levels are influenced by trophic position and natural species variability, independent of local pollution.
• Chemical-specific analysis considering the food chain is essential for effective contamination management.