Bivalve Shellfish Safety in Portugal: Variability of Faecal Levels, Metal Contaminants and Marine Biotoxins during the Last Decade (2011-2020)

• Published in: Toxins Vol. 15; no. 2; p. 91
• Main Authors: Braga, Ana Catarina, Rodrigues, Susana Margarida, Lourenço, Helena Maria, Costa, Pedro Reis, Pedro, Sónia
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 2023; MDPI
• Subjects: Animals; Anthropogenic factors; Aquaculture; Bioaccumulation; Bivalvia; Coastal ecology; Coastal waters; Coasts; Consumers; Consumption; Contaminants; Contamination; E coli; Environmental Monitoring - methods; Estuaries; faecal contamination; Feces; Food contamination & poisoning; Health aspects; Health risk assessment; Health risks; Heavy metals; Human influences; Humans; Hygiene; Invertebrates; Lagoons; Marine biology; marine biotoxins; Marine pollution; Marine toxins; Marine Toxins - analysis; metal contamination; Metals; Microbial contamination; Microorganisms; Mollusks; Monitoring; Portugal; Portuguese coast; Public health; Reclassification; Regulation; Risk management; Risk reduction; Safety and security measures; Seafood; seafood safety; Shellfish; Shellfish - analysis; Surveillance; Water quality; Portugal; seafood safety; shellfish; faecal contamination; Portuguese coast; marine biotoxins; metal contamination
• ISSN: 2072-6651; 2072-6651
• DOI: 10.3390/toxins15020091

Bivalves are a high-value product whose production has markedly increased, reaching 9863 tonnes in Portugal in 2021. Bivalves' habitats-lagoons, estuaries and coastal waters-are exposed to biological and anthropogenic contaminants, which can bioaccumulate in these organisms and pose a significant public health risk. The need to obtain a safe product for human consumption led to the implementation of standardised hygiene regulations for harvesting and marketing bivalve molluscs, resulting in routine monitoring of bivalve production areas for microbial quality, metal contaminants, and marine biotoxins. While excessive levels of biotoxins and metal contamination lead to temporary harvesting bans, high faecal contamination leads to area reclassification and impose post-harvest treatments. In this study, the seasonal and temporal variability of these parameters were analysed using historical data generated by the monitoring programme during the last decade. Moreover, the impact of the monitoring program on bivalve harvesting from 2011 to 2020 was assessed. This program presented a considerable improvement over time, with an increase in the sampling effort and the overall program representativeness. Finally, contamination risk, revising control measures, and defining recommendations for risk mitigation measures are given in the light of ten years' monitoring.