Trace metal concentrations in commercial fish, crabs, and bivalves from three lagoons in the South China Sea and implications for human health

Seafood is increasingly used worldwide due to its nutritional value. It is rich in essential minerals, liposoluble vitamins, and high-quality proteins. However, many seafood species tend to accumulate metals, making them a threat to human health. We chose Xincun Lagoon and Li-an Lagoon, which have been seriously polluted by local activities, and the relatively clean Tufu Bay as the research areas to investigate whether trace metals in economic seafood species in these areas threaten the food safety of consumers. The results show that the mean concentrations (mg kg−1 ww) of trace metals were Cu 0.22 ± 0.18, Pb 0.040 ± 0.028, Zn 5.25 ± 1.60, Cd 0.009 ± 0.004, Hg 0.0072 ± 0.0031, As 0.21 ± 0.12, and Cr 0.084 ± 0.048 in fish samples (Trachinotus ovatus); Cu 4.00 ± 0.96, Pb 0.075 ± 0.030, Zn 19.10 ± 2.64, Cd 0.050 ± 0.024, Hg 0.0131 ± 0.0035, As 0.91 ± 0.27, and Cr 0.216 ± 0.095 in crab samples (Charybdis natator); and Cu 5.37 ± 1.39, Pb 0.095 ± 0.023, Zn 21.38 ± 3.59, Cd 0.096 ± 0.026, Hg 0.0208 ± 0.0052, As 1.65 ± 0.59, and Cr 0.406 ± 0.117 in bivalve samples (Ruditapes philippinarum), respectively, with species specific (fish < crab < bivalve) and significant seasonal and spatial variation (p < 0.05). However, health risk assessment (EDI, THQ, TTHQ, CR) indicated that the consumption of the analyzed seafood from the study areas is safe for local consumers. But there is a potential risk for fishermen and those who prefer seafood.