Pb Content, Risk Level and Primary-Source Apportionment in Wheat and Rice Grains in the Lihe River Watershed, Taihu Region, Eastern China.

Lian Chen,Qingrong Li,Cuiming Tang,Dongxu Xing,Yang Xiao,Shenglu Zhou,Qiong Yang

doi:10.3390/ijerph18126256

Abstract

This study detailed a complete research from Lead (Pb) content level to ecological and health risk to direct- and primary-sources apportionment arising from wheat and rice grains, in the Lihe River Watershed of the Taihu region, East China. Ecological and health risk assessment were based on the pollution index and US Environmental Protection Agency (EPA) health risk assessment model. A three-stage quantitative analysis program based on Pb isotope analysis to determine the relative contributions of primary sources involving (1) direct-source apportionment in grains with a two-end-member model, (2) apportionment of soil and dustfall sources using the IsoSource model, and (3) the integration of results of (1) and (2) was notedly first proposed. The results indicated that mean contents of Pb in wheat and rice grains were 0.54 and 0.45 mg/kg and both the bio-concentration factors (BCF) were <<1; the ecological risk pollution indices were 1.35 for wheat grains and 1.11 for rice grains; hazard quotient (HQ) values for adult and child indicating health risks through ingestion of grains were all <1; Coal-fired industrial sources account for up to 60% of Pb in the grains. This study provides insights into the management of grain Pb pollution and a new method for its source apportionment.

Highlights

Pb is a heavy metal produced by the rapid economic development and greatly harmful to human body, especially to child
Most investigations to date have focused on assessing contamination level and sources of Pb in soils and atmospheric particles [9,10,11,12], with few focusing on Pb contamination and its source apportionment in grains that are essential for metabolism
We provided a new attempt to determine the primary sources in grains based on Pb isotope analysis and model calculation using a three-stage three-stage quantitative quantitative analysis analysis program involving (1) direct-source apportionment in grains with a two-end-member model, which can determine the contribution rate of soil and dustfall source apportionment forfor soilsoil andand dustfall usdustfallPb

Summary

Introduction

Pb is a heavy metal produced by the rapid economic development and greatly harmful to human body, especially to child. Human exposure to Pb occurs primarily through inhalation and ingestion, causing adverse health effects such as neurological and kidney diseases, even at low exposure levels [1,2,3,4], and Pb contamination in environmental compartments (rural soils, atmospheric dustfall, and food) has been partly documented in some articles [4,5,6,7,8,9]. Mean concentrations of Pb in dustfall was 223.86 mg/kg, significantly higher than background values. The mean Pb concentration in the dustfall was significantly higher than background values, with almost nine times higher than the background value. These results all indicated relatively high degrees of contamination in dustfall of this region

Methods

Results

Conclusion