Quantification of insecticides in commercial seafood sold in East Asian markets: risk assessment for consumers

The extraction of 21 insecticides and 5 metabolites was performed using an optimized and validated QuEChERS protocol that was further used for the quantification (GC-MS/MS) in several seafood matrices (crustaceans, bivalves, and fish-mudskippers). Seven species, acquired from Hong Kong and Macao wet markets ( a region so far poorly monitored), were selected based on their commercial importance in the Indo-Pacific region, market abundance, and affordable price. Among them, mussels from Hong Kong, together with mudskippers from Macao, presented the highest insecticide concentrations (median values of 30.33 and 23.90 ng/g WW, respectively). Residual levels of fenobucarb, DDTs, HCHs, and heptachlors were above the established threshold (10 ng/g WW) for human consumption according to the European and Chinese legislations: for example, in fish-mudskippers, DDTs, fenobucarb, and heptachlors (5-, 20- and tenfold, respectively), and in bivalves, HCHs (fourfold) had higher levels than the threshold. Risk assessment revealed potential human health effects ( e.g., neurotoxicity), especially through fish and bivalve consumption (non- carcinogenic risk; Sigma HQ(LT) > 1), and a potential concern of lifetime cancer risk development through the consumption of fish, bivalves, and crustaceans collected from these markets ( carcinogenic risk; Sigma TCR > 10(-4)). Since these results indicate polluted regions, where the seafood is collected/produced, a strict monitoring framework should be implemented in those areas to improve food quality and safety of seafood products.

Automated summary

This study used an optimized and validated QuEChERS protocol to extract and quantify 21 insecticides and 5 metabolites in seafood samples (crustaceans, bivalves, and fish-mudskippers). Seven species from the poorly monitored Hong Kong and Macao wet markets were selected based on their commercial importance, abundance, and affordability. The results showed high concentrations of insecticides in mussels from Hong Kong and mudskippers from Macao, suggesting potential health risks, such as neurotoxicity and carcinogenicity, associated with the consumption of fish, bivalves, and crustaceans from these markets. Strict monitoring measures should be implemented to improve the quality and safety of seafood products.