Accumulation, subcellular distribution, and ecological risk assessment of Pb and Cd in Bellamya aeruginosa from the Xiangjiang River, China

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.

KEYWORDS:

• Pb and Cd
• Xiangjiang River
• Bellamya aeruginosa
• accumulation
• subcellular distribution
• ecological risk

Acknowledgements

We would also like to thank the anonymous referees for their valuable suggestions.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Notes on contributors

Jun Liu is an associate professor of University of South China. He earned a Ph.D. in ecology from Hunan Agricultural University in 2010.

Wei Huang is a master student in biology at University of South China.

Zhiliang Li is a master student in biology at University of South China.

Jingsong Hu is a lecturer of University of South China. He earned a Ph.D. in botany from Hunan Normal University in 2013.

Yunhua Zhu is a lecturer of University of South China. She earned a Ph.D. in biochemistry from Hunan Agricultural University in 2013.

Hongyan Xie is a lecturer of University of South China. She earned a master's degree in botany from Hunan Agricultural University in 2013.

Cuiying Peng is a professor of University of South China. She earned a Ph.D. in Genetics from Central South University in 2010.

Additional information

Funding

Liu Jun was Supported by Scientific Research Fund of Hunan Provincial Education Department (15A168), Hunan Provincial Natural Science Foundation of China (2018JJ2325), Project of Hengyang Science and Technology Bureau (2018KJ111, 2016KF14), The Key Laboratory of Ecological Environment and Critical Human Diseases Prevention of Hunan Province Department of Education (Hunan Provincial Education Department document (Approval number: 2019-379)), and College students’ research learning and innovative experimental project of University of South China (2018XJXZ203, 2018XJXZ396, X2019170).