Airborne lead: A vital factor influencing rice lead accumulation in China

• Published in: Journal of hazardous materials Vol. 427; p. 128169
• Main Authors: Lin, Qi, Dai, Wei, Chen, Jun-Qiao, Jin, Yu, Yang, Yue, Wang, Yi-Yi, Zhang, Bao-Feng, Fan, Jia-Ming, Lou, Li-Ping, Shen, Zhen-Guo, Shen, Chao-Feng, Mao, Jing-Dong
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 05.04.2022
• Subjects: Aerosol lead; China; Edible Grain - chemistry; Foliar uptake; Genotype; Lead; Oryza; Predictive model; Rice; Soil; Soil Pollutants - analysis; China; Genotype; Foliar uptake; Aerosol lead; China; Predictive model; Rice
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2021.128169

Traditionally, lead (Pb) in rice grains has been thought to be mostly derived from soil, and the contribution of aerosol Pb remains so far unknown. Based on a meta-analysis, we surprisingly found rice Pb content decreased proportionally with urban atmospheric Pb concentrations in major rice-growing provinces in China during 2001–2015, suggestive of the strong influence of long-range Pb transport on agricultural environment. With the combination of field survey, field experiment, as well as a predictive model, we confirmed high contribution of atmospheric exposure to rice grain Pb in China. We for the first time developed a predictive mathematical model which revealed that aerosol Pb accumulation ratios of rice grains were related to both grain weight and accumulation types. We successfully predicted the national-scale rice Pb in China on the basis of the public data of urban PM2.5 from 19 rice-growing provinces and proposed a seasonal atmospheric Pb limit of 0.20 µg m−3 based on the safe threshold level of Pb in rice, which was much lower than the current limit of 1 µg m−3 set in China. [Display omitted] •High contribution of atmospheric exposure in lead accumulation of rice grains in China.•Predictive mathematical model for aerosol Pb accumulation ratios of rice grains is developed.•Atmospheric Pb concentrations can be included for predicting the regional average rice Pb.•Atmospheric seasonal Pb limit of 0.20 µg m− 3 for rice safety is proposed.