Open AccessDynamics of Lead Bioavailability and Speciation in Indoor Dust and X-ray Spectroscopic Investigation of the Link between Ingestion and Inhalation Pathways
Author(s) -
Farzana Kastury,
Euan Smith,
Enzo Lombi,
Martin Donnelley,
Patricia Cmielewski,
David Parsons,
Matt Noerpel,
Kirk G. Scheckel,
Andrew Kingston,
Glenn R. Myers,
David Paterson,
Martin D. de Jonge,
Albert L. Juhasz
Publication year - 2019
Publication title -
environmental science and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.851
H-Index - 397
eISSN - 1520-5851
pISSN - 0013-936X
DOI - 10.1021/acs.est.9b03249
Subject(s) - bioavailability , chemistry , environmental chemistry , gastric emptying , absorption (acoustics) , inhalation , ingestion , inhalation exposure , stomach , materials science , toxicity , pharmacology , medicine , biochemistry , organic chemistry , composite material , anatomy
Lead (Pb) exposure from household dust is a major childhood health concern because of its adverse impact on cognitive development. This study investigated the absorption kinetics of Pb from indoor dust following a single dose instillation into C57BL/6 mice. Blood Pb concentration (PbB) was assessed over 24 h, and the dynamics of particles in the lung and gastro-intestinal (GI) tract were visualized using X-ray fluorescence (XRF) microscopy. The influence of mineralogy on Pb absorption and particle retention was investigated using X-ray absorption near-edge structure spectroscopy. A rapid rise in PbB was observed between 0.25 and 4 h after instillation, peaking at 8 h and slowly declining during a period of 24 h. Following clearance from the lungs, Pb particles were detected in the stomach and small intestine at 4 and 8 h, respectively. Analysis of Pb mineralogy in the residual particles in tissues at 8 h showed that mineral-sorbed Pb and Pb-phosphates dominated the lung, while organic-bound Pb and galena were the main phases in the small intestines. This is the first study to visualize Pb dynamics in the lung and GI tract using XRF microscopy and link the inhalation and ingestion pathways for metal exposure assessment from dust.