ABSTRACT Field investigation and laboratory experiments were conducted to study the Pb and Cd tolerance mechanism of Bellamya aeruginosa from the Xiangjiang River. B. aeruginosa were collected from the middle reaches of the Xiangjiang River, and their Pb and Cd accumulation and subcellular distribution, as well as the related ecological risks, were analysed. Results showed significant differences between Pb and Cd accumulation and distribution in B. aeruginosa. Cd concentration was distributed in the following decreasing order: visceral mass > mantle > foot > shell, with the visceral mass and mantle being the main Cd accumulation sites. The shell was the main part accumulating Pb in B. aeruginosa, with Pb not being detected in soft tissues. Differential centrifugation revealed Cd subcellular distribution, i.e. lysosomes and mitochondria were the important accumulation and effect sites of Cd in B. aeruginosa cells. Cd subcellular distribution effectively reduced Cd damage on the nuclei, which improved the Cd tolerance of B. aeruginosa. The single factor pollution (Pi) and metal pollution (MPI) indices showed that the middle reaches of the Xiangjiang River had been seriously polluted by Pb and Cd. Cd pollution was particularly serious, accumulating in B. aeruginosa, which constituted a food safety hazard to humans.

中文翻译：

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湘江铜绿藻Pb、Cd的积累、亚细胞分布及生态风险评估

摘要 通过田间调查和室内试验，研究了湘江铜绿贝拉姆菌对铅、镉的耐受机制。从湘江中游采集铜绿假单胞菌，对其Pb、Cd的积累、亚细胞分布及相关生态风险进行了分析。结果表明铜绿假单胞菌中铅和镉的积累和分布存在显着差异。Cd浓度呈递减顺序分布：内脏块>地幔>足>壳，内脏块和地幔是主要的Cd积累位点。贝壳是铜绿假单胞菌中铅积累的主要部分，软组织中未检测到铅。差速离心揭示了 Cd 亚细胞分布，即 溶酶体和线粒体是铜绿假单胞菌细胞中镉的重要积累和作用位点。Cd亚细胞分布有效减少了细胞核的Cd损伤，提高了铜绿假单胞菌对Cd的耐受性。单因素污染（Pi）和金属污染（MPI）指数表明，湘江中游地区已受到铅、镉的严重污染。镉污染尤为严重，在铜绿假单胞菌中积累，对人类构成食品安全隐患。单因素污染（Pi）和金属污染（MPI）指数表明，湘江中游地区已受到铅、镉的严重污染。镉污染尤为严重，在铜绿假单胞菌中积累，对人类构成食品安全隐患。单因素污染（Pi）和金属污染（MPI）指数表明，湘江中游地区已受到铅、镉的严重污染。镉污染尤为严重，在铜绿假单胞菌中积累，对人类构成食品安全隐患。