Cadmium and arsenic accumulation during the rice growth period under in situ remediation

Jiao-Feng Gu; Hang Zhou; Hui-Ling Tang; Wen-Tao Yang; Min Zeng; Zhi-Ming Liu; Pei-Qin Peng; Bo-Han Liao

doi:10.1016/j.ecoenv.2019.01.003

Cadmium and arsenic accumulation during the rice growth period under in situ remediation

Ecotoxicol Environ Saf. 2019 Apr 30:171:451-459. doi: 10.1016/j.ecoenv.2019.01.003. Epub 2019 Jan 9.

Authors

Jiao-Feng Gu¹, Hang Zhou², Hui-Ling Tang³, Wen-Tao Yang⁴, Min Zeng⁵, Zhi-Ming Liu⁶, Pei-Qin Peng⁷, Bo-Han Liao⁸

Affiliations

¹ College of Environment Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China; Hunan Engineering Laboratory for Control of Rice Quality and Safety, Changsha 410004, China. Electronic address: gujiaofeng@163.com.
² College of Environment Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China; Hunan Engineering Laboratory for Control of Rice Quality and Safety, Changsha 410004, China. Electronic address: zhouhang4607@163.com.
³ College of Environment Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China. Electronic address: TLmorn@163.com.
⁴ College of Environment Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China. Electronic address: wtyang0803@163.com.
⁵ College of Environment Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China. Electronic address: emailzm@163.com.
⁶ College of Environment Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China; Department of Biology, Eastern New Mexico University, Portales, NM 88130, USA. Electronic address: zhiming.liu@enmu.edu.
⁷ College of Environment Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China; Hunan Engineering Laboratory for Control of Rice Quality and Safety, Changsha 410004, China. Electronic address: pqpeng123@sina.com.
⁸ College of Environment Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China; Hunan Engineering Laboratory for Control of Rice Quality and Safety, Changsha 410004, China. Electronic address: liaobohan1020@163.com.

PMID: 30639871
DOI: 10.1016/j.ecoenv.2019.01.003

Abstract

Rice (Oryza sativa L.) planted in cadmium (Cd)- and arsenic (As)-contaminated soil is considered the main source of dietary Cd and As intake for humans in Southeast Asia and thereby poses a threat to human health. Minimizing the transfer of these pollutants to rice grain is an urgent task for environmental researchers. The main objective of this study was to investigate the effects and the mechanisms of a combined amendment (hydroxyapatite + zeolite + biochar, HZB) on decreasing Cd and As accumulation in rice. In situ remediation and aqueous solution adsorption experiments were conducted. The results showed that after application of HZB, Cd and As concentrations of the exchangeable fraction and TCLP extraction in soil decreased with the growth of rice plants. Cd concentrations in rice tissues were decreased at the tillering, filling and maturing stages after in situ remediation, while As concentrations in rice tissues were decreased only at the maturing stage. When 8 kg·plot^-1 (9000 kg ha^-1) HZB was applied, concentrations of Cd and inorganic As in brown rice were decreased to 0.18 and 0.16 mg kg^-1, respectively, lower than the levels permissible for grain in China, i.e., 0.2 mg kg^-1. Application of HZB reduced Cd accumulation in rice tissues, and the suppression of Cd accumulation was significantly greater than that of As. Furthermore, HZB significantly increased rice grain yield. An aqueous solution adsorption experiment demonstrated that HZB could adsorb and covalently bind Cd and As (V) via -OH, -COOH, -Si-O-Si and CO₃^2- groups to produce carboxylates, silicates and carbonates, thereby promoting in situ immobilization of Cd and As in soil solution.

Keywords: Accumulation; Arsenic; Cadmium; In situ remediation; Rice; Soil.

MeSH terms

Arsenic / analysis*
Cadmium / analysis*
Charcoal / chemistry
China
Edible Grain / drug effects
Edible Grain / genetics
Hydrogen-Ion Concentration
Oryza / drug effects
Oryza / growth & development*
Soil / chemistry
Soil Pollutants / analysis*
Spectroscopy, Fourier Transform Infrared
Zeolites / chemistry

Substances

Soil
Soil Pollutants
biochar
Cadmium
Zeolites
Charcoal
Arsenic