Development and validation of single-step microwave-assisted digestion method for determining heavy metals in aquatic...

A simple, rapid, and environmentally friendly microwave-assisted digestion method was developed and validated to determine heavy metals in aquatic products. The method could digest 640 samples using only one microwave digester in an 8 h working day. Only 2 mL of nitric acid was required to completely digest 0.2 g of samples, significantly reducing the usage of acid. The method was applied to investigate the heavy metals concentrations in mostly consumed aquatic products in Shenzhen. The investigation showed significant differences between different sampling times and sites in the concentrations of heavy metals, implying the necessity of sampling based on multiple times and sites for the accurate determination of heavy metals. Besides, iAs in crab were found to exceed the Chinese standard limit (GB 2762-2022). Health risk assessment showed that Cd and iAs in P. trituberculatus and R. philippinarum posed potential non-carcinogenic and carcinogenic risks to residents' health.