Accurately distinguishing between the endogenous formation and exogenous exposure of Fe-bearing particles(e.g.,magnetic Fe particles)within biological organisms is the prerequisite for scientifically evaluating their ...Accurately distinguishing between the endogenous formation and exogenous exposure of Fe-bearing particles(e.g.,magnetic Fe particles)within biological organisms is the prerequisite for scientifically evaluating their health risks.However,this remains a challenging task due to lacking the comprehensive understanding of the endogenous formation process of Fe-bearing particles.Here,we report the formation dynamics of Fe-bearing particles under conditions closely resembling actual physiological conditions,and compare the morphological and structural differences between endogenous and exogenous Fe-bearing particles.We find that Fe-bearing particles can indeed form under physiological conditions at 37℃.In this process,phosphate plays a crucial role in the oxidation and mineralization of iron ions.Moreover,endogenously formed Fe-bearing particles typically have a diameter of less than8 nm,and iron is the only metal element present.Therefore,we propose that Fe-bearing particles found in the body with a diameter larger than 8 nm are mainly derived from exogenous exposure.For Fe-bearing particles smaller than 8 nm,it is necessary to combine associated elements and crystal structure characteristics to distinguish between endogenous and exogenous sources.This study provides direct evidence from endogenous metabolism for tracing Fe-bearing particles,especially magnetic iron particles,within the human body.展开更多
Oxidation remediation is a commonly used technology for PAHs contaminated soil presently,but the overestimate of efficiency due to ongoing remediation by residual oxidants during extraction and testing has not been pa...Oxidation remediation is a commonly used technology for PAHs contaminated soil presently,but the overestimate of efficiency due to ongoing remediation by residual oxidants during extraction and testing has not been paid enough attention.In this study,persulfate was activated by Fe(Ⅱ)to investigate the effects of residual oxidants on PAHs removal during detection process and the elimination effects of adding Na_(2)SO_(3) and extending sampling time on residual oxidants.Results verified that the residual oxidants removed PAHs in extraction process,making the results lower than the actual values:the detection recovery rate η of ΣPAHs and 3-6 ring PAHs ranged from 24.3%(25%Na_(2)S_(2)O_(8)treatment)to 87.4%(5%Na_(2)S_(2)O_(8)+4/4Fe^(2+) treatment),20.1%-99.0%,28.9%-87.9%,20.8%-89.4%,and 1.8.6%-76.9%,respectively.After adding Na_(2)SO_(3),the accuracy of detection results increased significantly:the η of ΣPAHs and 3-6 ring PAHs increased to 64.1%-96.5%,58.8%-95.5%,73.8%-114.4%,60.6%-95.6%,and 45.4%-77.1%,respectively.After 49 days of adding oxidants,residual oxidants had no considerable effect on the detection of PAHs,indicating it was appropriate to start soil remediation verification sampling49 days after the remediation was completed.The observed results will help scientific evaluation of the remediation effects of chemical oxidation on or-ganic contaminated soil.展开更多
基金supported by the National Natural Science Foundation of China(Nos.22222610,22376202,and 22193051)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB0750100)+1 种基金Chinese Academy of Sciences Project for Young in Basic Research(No.YSBR-086)the National Key R&D Program of China(Nos.2023YFF0614200 and 2023YFC3708301)。
文摘Accurately distinguishing between the endogenous formation and exogenous exposure of Fe-bearing particles(e.g.,magnetic Fe particles)within biological organisms is the prerequisite for scientifically evaluating their health risks.However,this remains a challenging task due to lacking the comprehensive understanding of the endogenous formation process of Fe-bearing particles.Here,we report the formation dynamics of Fe-bearing particles under conditions closely resembling actual physiological conditions,and compare the morphological and structural differences between endogenous and exogenous Fe-bearing particles.We find that Fe-bearing particles can indeed form under physiological conditions at 37℃.In this process,phosphate plays a crucial role in the oxidation and mineralization of iron ions.Moreover,endogenously formed Fe-bearing particles typically have a diameter of less than8 nm,and iron is the only metal element present.Therefore,we propose that Fe-bearing particles found in the body with a diameter larger than 8 nm are mainly derived from exogenous exposure.For Fe-bearing particles smaller than 8 nm,it is necessary to combine associated elements and crystal structure characteristics to distinguish between endogenous and exogenous sources.This study provides direct evidence from endogenous metabolism for tracing Fe-bearing particles,especially magnetic iron particles,within the human body.
基金supported by the Research and Demonstration Program of Yunnan Province for Soil Environmental Management System Construction and Key Remediation TechnologyNational Key Research and Development Program of China (No. 2018YFC1802200).
文摘Oxidation remediation is a commonly used technology for PAHs contaminated soil presently,but the overestimate of efficiency due to ongoing remediation by residual oxidants during extraction and testing has not been paid enough attention.In this study,persulfate was activated by Fe(Ⅱ)to investigate the effects of residual oxidants on PAHs removal during detection process and the elimination effects of adding Na_(2)SO_(3) and extending sampling time on residual oxidants.Results verified that the residual oxidants removed PAHs in extraction process,making the results lower than the actual values:the detection recovery rate η of ΣPAHs and 3-6 ring PAHs ranged from 24.3%(25%Na_(2)S_(2)O_(8)treatment)to 87.4%(5%Na_(2)S_(2)O_(8)+4/4Fe^(2+) treatment),20.1%-99.0%,28.9%-87.9%,20.8%-89.4%,and 1.8.6%-76.9%,respectively.After adding Na_(2)SO_(3),the accuracy of detection results increased significantly:the η of ΣPAHs and 3-6 ring PAHs increased to 64.1%-96.5%,58.8%-95.5%,73.8%-114.4%,60.6%-95.6%,and 45.4%-77.1%,respectively.After 49 days of adding oxidants,residual oxidants had no considerable effect on the detection of PAHs,indicating it was appropriate to start soil remediation verification sampling49 days after the remediation was completed.The observed results will help scientific evaluation of the remediation effects of chemical oxidation on or-ganic contaminated soil.
