Dynamics of Lead Bioavailability and Speciation in Indoor Dust and X-ray Spectroscopic Investigation of the Link between Ingestion and Inhalation Pathways.
Farzana KasturyEuan SmithEnzo LombiMartin W DonnelleyPatricia L CmielewskiDavid W ParsonsMatt NoerpelKirk G ScheckelAndrew M KingstonGlenn R MyersDavid PatersonMartin D de JongeAlbert L JuhaszPublished in: Environmental science & technology (2019)
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.
Keyphrases
- heavy metals
- health risk
- health risk assessment
- aqueous solution
- high resolution
- risk assessment
- single molecule
- human health
- public health
- emergency department
- air pollution
- high throughput
- type diabetes
- adipose tissue
- mass spectrometry
- healthcare
- optical coherence tomography
- magnetic resonance imaging
- skeletal muscle
- young adults
- dual energy
- sensitive detection
- health information
- label free
- childhood cancer
- loop mediated isothermal amplification
- electron microscopy