Effects of cadmium pollution on the safety of rice and fish in a rice-fish coculture system

Wei Luo; Dongjie Wang; Zhou Xu; Guoping Liao; Defang Chen; Xiaoli Huang; Yan Wang; Song Yang; Liulan Zhao; Huagang Huang; Yuliang Li; Wenyan Wei; Yuejin Long; Zongjun Du

doi:10.1016/j.envint.2020.105898

Effects of cadmium pollution on the safety of rice and fish in a rice-fish coculture system

Environ Int. 2020 Oct:143:105898. doi: 10.1016/j.envint.2020.105898. Epub 2020 Jul 2.

Authors

Wei Luo¹, Dongjie Wang¹, Zhou Xu¹, Guoping Liao¹, Defang Chen¹, Xiaoli Huang¹, Yan Wang¹, Song Yang¹, Liulan Zhao¹, Huagang Huang², Yuliang Li³, Wenyan Wei³, Yuejin Long⁴, Zongjun Du⁵

Affiliations

¹ College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 611130, China.
² College of Resources, Sichuan Agricultural University, Chengdu 611130, China.
³ Fisheries Research Institute, Chengdu Academy of Agricultural and Forestry Sciences, Chengdu 611130, China.
⁴ ZiyangYanjiang District Agricultural Bureau, Ziyang 641300, Sichuan, China.
⁵ College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 611130, China. Electronic address: 14364@sicau.edu.cn.

PMID: 32623219
DOI: 10.1016/j.envint.2020.105898

Abstract

The rice-fish coculture system (RFS) is one of the most important and environmentally friendly agricultural systems in the world. With the increasing amounts of heavy metal contamination in the soil and water, the safe production of RFS has been greatly threatened. However, there are no reports on heavy metal uptake by rice and fish in a RFS. In this study, a model of cadmium (Cd)-contaminated RFS with the addition of 0-40.00 mg kg^-1Cd was simulated in the field. The accumulation of Cd in the rice and fish increased as the level of Cd contamination increased. Regardless of the level of contamination, the order of Cd accumulation in the rice was root > stem ≈ leaf > rice grain > brown grain and in the fish was liver ≈ gut > kidney > gill > muscle. The dissolved oxygen (DO) and the transparency of water were significantly reduced after the fish were added. The tendency of the Cd to accumulate in the fish correlated with the change of the concentration of Cd in the water (P < 0.05). According to the maximum level of Cd in the brown grains (0.40 mg kg^-1) and in the fish muscle (0.10 mg kg^-1) of Codex Alimentarius Commission (CAC), the safety threshold of soil Cd for the rice and the fish was calculated to be 5.86 mg kg^-1 and 31.47 mg kg^-1, respectively, indicating that the safety risk to the rice was much greater in a Cd-contaminated RFS.

Keywords: Accumulation; Cadmium (Cd); Rice-fish coculture system (RFS); Safety threshold value.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Cadmium / analysis
Cadmium / toxicity
Coculture Techniques
Oryza*
Soil
Soil Pollutants* / analysis
Soil Pollutants* / toxicity

Substances

Soil
Soil Pollutants
Cadmium