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Indoor dust can be a major source of heavy metals, nutrients, and bacterial contamination in residential environments and may cause serious health problems. The goal of this research is to characterize chemical and bacterial contaminants of indoor, settled house dust in the Houston Metropolitan region. To achieve this, a total of 31 indoor dust samples were collected, along with household survey data, which were subsequently analyzed for elemental and bacterial concentrations. Microscopic and geospatial analysis was conducted to characterize and map potential hotspots of contamination. Interestingly Cd, Cr, Cu, Pb, and Zn concentrations of all 31 indoor dust samples were significantly enriched and exceeded soil background concentrations. Furthermore, As, Cd, Pb, and Zn concentrations in the dust samples were significantly correlated to the enteric bacterial load concentrations. Human health assessment revealed that cancer risk values via ingestion for Cd, Cr, and Ni were greater than the acceptable range. Of our 31 dust sample isolates, three Gram-negative and 16 Gram-positive pathogenic bacteria were identified, capable of causing a wide range of diseases. Our results demonstrate that both chemical and bacterial characterization of indoor dust coupled with spatial mapping is essential to assess and monitor human and ecological health risks.
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This content will become publicly available on June 18, 2026
Indoor surface chemistry variability: microspectroscopic analysis of deposited particles in dwellings across the United States
The indoor surfaces of dwellings across the United States range exhibit a wide range of chemical compositions and physical properties, which impacts semi-volatile partitioning, heterogeneous chemistry and the overall properties of indoor air.
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- Award ID(s):
- 2203982
- PAR ID:
- 10635995
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Environmental Science: Processes & Impacts
- Volume:
- 27
- Issue:
- 6
- ISSN:
- 2050-7887
- Page Range / eLocation ID:
- 1704 to 1713
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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