Fast In, Faster Out: Rapid Thallium Elimination Drives Low Bioaccumulation in Coastal Gastropods

作者：Xinxin Ma, Wenze Xiao, Qiong Zhang, Zhenming Yu, Xiaoke Jia, Rong Chen, Minwei Xie, Qiao‐Guo Tan · 发表于：Environmental Science & Technology · 年份：2025 · DOI：10.1021/acs.est.5c04432 · 被引用次数：4 · 研究领域：Thallium and Germanium Studies、Analytical chemistry methods development、Fullerene Chemistry and Applications

Thallium (Tl) ranks among the most toxic elements to humans, but its bioaccumulation and ecological risks in marine organisms remain poorly understood. In this study, we investigated the toxicokinetics of Tl in the intertidal snail Reishia clavigera, an ecologically and economically important gastropod native to East and Southeast Asia. Using the stable isotope 203 Tl as a tracer, we quantified Tl uptake and elimination under environmentally relevant conditions across salinity (15–30‰) and temperature (7–28 °C) gradients. Despite moderate uptake rates ( k u: 0.064–0.29 L g –1 day –1 ), Tl bioaccumulation remained low due to exceptionally fast elimination ( k e: 0.79–3.37 day –1 ), with biological half-lives as short as 0.21 days. Salinity suppressed Tl uptake without affecting elimination, while temperature increased both k u and k e . The resulting bioconcentration factors (BCF: 59–160 L kg –1 dry weight) were two to four orders of magnitude lower than those of other trace metals, indicating inherently weak Tl retention. Tissue-specific analyses showed a higher Tl retention in viscera than in muscle, largely driven by slower elimination. Our findings resolve the apparent paradox between Tl’s high mammalian toxicity and relatively lower aquatic toxicity, highlighting rapid elimination as the key controlling factor. This work underscores the importance of integrating toxicokinetics into ecological risk assessment and suggests that Tl tissue levels in marine mollusks primarily ...