Occurrence and health risk assessment of toxic metals and rare earth elements in microalgae: Insight into potential risk factors in new sustainable food resources.

Microalgae are a promising sustainable food source with high nutritional value and environmental benefits. This study investigated the presence of toxic metals and rare earth elements (REEs) in 68 microalgal-based food products and conducted a probabilistic risk assessment to evaluate potential health risks. The findings revealed high detection rates of REEs (80.96% to 100%) and heavy metals (83.82% to 100%), with REE concentrations ranging from 0.0055 to 0.5207 mg/kg. Heavy metals were detected at the following average concentrations: As (2.80 mg/kg) > Cr (1.27 mg/kg) > Pb (0.30 mg/kg) > Cd (0.20 mg/kg) > Hg (0.01 mg/kg). Carcinogenic risk analysis for Cd (3.004 × 10), Cr (1.484 × 10), and As (1.1283 × 10) indicated that 95th percentile values exceeded established safety thresholds (10). These findings highlight the critical need for stringent monitoring and the establishment of comprehensive regulatory frameworks for the safety of novel microalgae foods.