Physicochemical characterisation of diesel exhaust particles: Factors for assessing biological activity

Berube, Kelly Ann ORCID: https://orcid.org/0000-0002-7471-7229, Jones, Timothy Peter ORCID: https://orcid.org/0000-0002-4466-1260, Williamson, B. J., Winters, C., Morgan, Andrew John, Pooley, Frederick D. and Richards, Roy J. 1999. Physicochemical characterisation of diesel exhaust particles: Factors for assessing biological activity. Atmospheric Environment 33 (10) , pp. 1599-1614. 10.1016/S1352-2310(98)00384-7

Full text not available from this repository.

Abstract

A range of microscopy and analytical techniques have been used to investigate the physicochemical properties of diluted DEP that may be important in determining its biological activity. Transmission electron microscopy demonstrated four basic categories of particle morphology: (1) “spherulites” [individual particles]; (2) “chains” or “clusters” of spherulites; (3) “spherules”, [large bodies of spherulites]; (4) “flake-like bodies”. Image analysis of TEM photomicrographs determined empirical morphological parameters (30 nm mean spherulite diameter, aspect ratio 1.5, mean particle area 0.078 μm, equivalent spherical diameter 0.23 μm, roundness 2.76) and derived parameters (0.313 μm2 surface area, 3.7 μm2 pg surface area per mass and 0.042 μm3 volume) of DEP. Distributions of the particle sizes by number showed 10.1% were ultrafine (<0.1 μm), 89.5% fine (0.1–2.0 μm), 0.4% coarse (>2.5 μm), but distributions based on a mass value were different (0.01% ultrafine; 52.6% fine, 47.4% coarse). In contrast, impacted DEP contained 60.87% ultrafine, 39.13% fine and 0% coarse particles by number. Field emission scanning electron microscopy of spherulites revealed smooth surfaces and flocculated spherules with large surface areas. Electron probe X-ray micro-analysis demonstrated the presence of C, O, Na, Mg, K, Al, Si, P, S, Cl, Ca along with a range of metals (Ti, Mn, Fe, Zn, Cr), that were heterogeneous in distribution. Inductively coupled plasma mass and atomic emission spectrometry identified Mg, P, Ca, Cr, Mn, Zn, Sr, Mo, Ba, Na, Fe, S, and Si as the mobile sorbed metals readily removed during sonication in water from DEP suspensions. X-ray Diffraction confirmed previous observations of the presence of nanometer sized crystallites of disordered graphite. Comparison of microscopy and analytical results between sonicated and impacted DEP revealed a physicochemical difference that must be taken into account in any toxicological investigations.

Item Type:	Article
Date Type:	Publication
Status:	Published
Schools:	Biosciences Earth and Environmental Sciences
Subjects:	G Geography. Anthropology. Recreation > GE Environmental Sciences Q Science > Q Science (General)
Uncontrolled Keywords:	Biopersistence; Microscopy; Microanalysis; Pollution; PM10
Publisher:	Elsevier
ISSN:	0004-6981
Last Modified:	05 Aug 2024 08:27
URI:	https://orca.cardiff.ac.uk/id/eprint/21890

Citation Data

Cited 186 times in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item