Application of biochar to soil reduces cancer risk via rice consumption: a case study in Miaoqian village, Longyan, China.

Abstract

Consumption of rice contaminated with potentially toxic elements (PTEs) is a major pathway for human exposure to PTEs. This is particularly true in China's so called "Cancer Villages". In this study, sewage sludge biochar (SSBC) was applied to soil (at 5% and 10%) to suppress PTE phytoavailability and as a consequence to reduce PTE levels in rice grown in mining impacted paddy soils. Risk assessment indicated that SSBC addition (10%) markedly (P≤0.05) decreased the daily intake, associated with the consumption of rice, of PTEs (As, Cd, Co, Cu, Mn, Pb and Zn by: 68, 42, 55, 29, 43, 38 and 22%, respectively). In treatments containing SSBC (10%) the health quotient (HQ) indices for PTEs (except for As, Cu and Mn) were <1, indicating that SSBC suppressed the health risk associated with PTEs in rice. The addition of SSBC (10%) markedly (P≤0.01) reduced AsIII (72%), dimethylarsinic acid (DMA) (74%) and AsV (62%) concentrations in rice. Consequentially, following SSBC application (10%), the incremental lifetime cancer (ILTR) value for iAs (AsIII+AsV) associated with the consumption of rice was significantly (P≤0.01) reduced by 66%. These findings suggest that SSBC could be a useful soil amendment to mitigating PTE exposure, through rice consumption, in China's "Cancer Villages".

• Authors: Sardar Khan, Brian J Reid, Gang Li, Yong-Guan Zhu
• Journal: Environment international (Environ Int) Vol. 68 Pg. 154-61 (Jul 2014) ISSN: 1873-6750 [Electronic] Netherlands
• PMID: 24727070 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2014 Elsevier Ltd. All rights reserved.

Chemical References

• Metals, Heavy
• Sewage
• Soil
• Soil Pollutants
• biochar
• Charcoal

Topics

• Biomass
• Charcoal (chemistry)
• China
• Diet
• Environmental Exposure
• Food Contamination (prevention & control)
• Humans
• Metals, Heavy (chemistry, metabolism)
• Neoplasms (prevention & control)
• Oryza (chemistry, metabolism)
• Plant Leaves (chemistry, metabolism)
• Plant Stems (chemistry, metabolism)
• Risk Factors
• Seeds (chemistry, metabolism)
• Sewage (chemistry)
• Soil (chemistry)
• Soil Pollutants (chemistry, toxicity)