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Cytotoxicity assessment of some carbon nanotubes and related carbon nanoparticle aggregates and the implications for anthropogenic carbon nanotube aggregates in the environment.

Murr LE, Garza KM, Soto KF, Carrasco A, Powell TG, Ramirez DA, Guerrero PA, Lopez DA, Venzor J - Int J Environ Res Public Health (2005)

Bottom Line: Toxicological studies, while sparse, have been concerned with virtually uncharacterized, single wall carbon nanotubes, and the conclusions have been conflicting and uncertain.These results suggest a number of novel epidemiological and etiological avenues for asthma triggers and related respiratory or other environmental health effects, especially since indoor number concentrations for multiwall carbon nanotube aggregates is at least 10 times the outdoor concentration, and virtually all gas combustion processes are variously effective sources.These results also raise concerns for manufactured carbon nanotube aggregates, and related fullerene nanoparticles.

View Article: PubMed Central - PubMed

Affiliation: Department of Metallurgical and Materials Engineering, The University of Texas at El Paso, El Paso, Texas 79968, USA. fekberg@utep.edu

ABSTRACT
Nanotechnology and nanomaterials have become the new frontier world-wide over the past few years and prospects for the production and novel uses of large quantities of carbon nanotubes in particular are becoming an increasing reality. Correspondingly, the potential health risks for these and other nanoparticulate materials have been of considerable concern. Toxicological studies, while sparse, have been concerned with virtually uncharacterized, single wall carbon nanotubes, and the conclusions have been conflicting and uncertain. In this research we performed viability assays on a murine lung macrophage cell line to assess the comparative cytotoxicity of commercial, single wall carbon nanotubes (ropes) and two different multiwall carbon nanotube samples; utilizing chrysotile asbestos nanotubes and black carbon nanoaggregates as toxicity standards. These nanotube materials were completely characterized by transmission electron microscopy and observed to be aggregates ranging from 1 to 2 microm in mean diameter, with closed ends. The cytotoxicity data indicated a strong concentration relationship and toxicity for all the carbon nanotube materials relative to the asbestos nanotubes and black carbon. A commercial multiwall carbon nanotube aggregate exhibiting this significant cell response was observed to be identical in structure to multiwall carbon nanotube aggregates demonstrated to be ubiquitous in the environment, and especially in indoor environments, where natural gas or propane cooking stoves exist. Correspondingly, preliminary epidemiological data, although sparse, indicate a correlation between asthma incidence or classification, and exposure to gas stoves. These results suggest a number of novel epidemiological and etiological avenues for asthma triggers and related respiratory or other environmental health effects, especially since indoor number concentrations for multiwall carbon nanotube aggregates is at least 10 times the outdoor concentration, and virtually all gas combustion processes are variously effective sources. These results also raise concerns for manufactured carbon nanotube aggregates, and related fullerene nanoparticles.

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TEM bright-field image for black carbon (BC) (VULCAN-XC-72) (After Murr, et al. [17]).(a) Aggregates composed of complex, branched, turbostratic carbon spherules. The SAED pattern insert shows diffuse diffraction (graphitic) rings characteristic of the turbostratic (mostly amorphous) spherule structure.(b) A typical aggregate of carbon spherules characteristic of diesel (bus) soot particulates collected in the outdoor air by thermal precipitation.
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f5-ijerph-02-00031: TEM bright-field image for black carbon (BC) (VULCAN-XC-72) (After Murr, et al. [17]).(a) Aggregates composed of complex, branched, turbostratic carbon spherules. The SAED pattern insert shows diffuse diffraction (graphitic) rings characteristic of the turbostratic (mostly amorphous) spherule structure.(b) A typical aggregate of carbon spherules characteristic of diesel (bus) soot particulates collected in the outdoor air by thermal precipitation.

Mentions: Figure 5(a) shows the BC (Vulcan XC-72) test material to be characterized by complex, branched aggregates of carbon spherules ranging in size from about 10 nm to 50 nm. The SAED pattern insert shows the same graphite diffraction rings shown in the SAED pattern insert in Figure 4(b) for aggregates of carbon nanotubes and fullerene polyhedra, but the diffraction ring intensity profiles exhibit a more diffuse amorphous-like microstructure consistent with the turbostratic, amorphous carbon and fullerene nanoparticle compositions of soots illustrated in recent high-resolution TEM studies by Grieco, et al. [30] and Vander Wal and Tomasek [31]. Correspondingly, Fig. 5(b) shows for comparison with Figure 5(a) typical diesel (truck) soot aggregate characterized by a similar, branched, fractal-like, carbon spherule aggregate; with spherule dimensions also ranging from about 10 nm to 50nm in diameter.


Cytotoxicity assessment of some carbon nanotubes and related carbon nanoparticle aggregates and the implications for anthropogenic carbon nanotube aggregates in the environment.

Murr LE, Garza KM, Soto KF, Carrasco A, Powell TG, Ramirez DA, Guerrero PA, Lopez DA, Venzor J - Int J Environ Res Public Health (2005)

TEM bright-field image for black carbon (BC) (VULCAN-XC-72) (After Murr, et al. [17]).(a) Aggregates composed of complex, branched, turbostratic carbon spherules. The SAED pattern insert shows diffuse diffraction (graphitic) rings characteristic of the turbostratic (mostly amorphous) spherule structure.(b) A typical aggregate of carbon spherules characteristic of diesel (bus) soot particulates collected in the outdoor air by thermal precipitation.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3814694&req=5

f5-ijerph-02-00031: TEM bright-field image for black carbon (BC) (VULCAN-XC-72) (After Murr, et al. [17]).(a) Aggregates composed of complex, branched, turbostratic carbon spherules. The SAED pattern insert shows diffuse diffraction (graphitic) rings characteristic of the turbostratic (mostly amorphous) spherule structure.(b) A typical aggregate of carbon spherules characteristic of diesel (bus) soot particulates collected in the outdoor air by thermal precipitation.
Mentions: Figure 5(a) shows the BC (Vulcan XC-72) test material to be characterized by complex, branched aggregates of carbon spherules ranging in size from about 10 nm to 50 nm. The SAED pattern insert shows the same graphite diffraction rings shown in the SAED pattern insert in Figure 4(b) for aggregates of carbon nanotubes and fullerene polyhedra, but the diffraction ring intensity profiles exhibit a more diffuse amorphous-like microstructure consistent with the turbostratic, amorphous carbon and fullerene nanoparticle compositions of soots illustrated in recent high-resolution TEM studies by Grieco, et al. [30] and Vander Wal and Tomasek [31]. Correspondingly, Fig. 5(b) shows for comparison with Figure 5(a) typical diesel (truck) soot aggregate characterized by a similar, branched, fractal-like, carbon spherule aggregate; with spherule dimensions also ranging from about 10 nm to 50nm in diameter.

Bottom Line: Toxicological studies, while sparse, have been concerned with virtually uncharacterized, single wall carbon nanotubes, and the conclusions have been conflicting and uncertain.These results suggest a number of novel epidemiological and etiological avenues for asthma triggers and related respiratory or other environmental health effects, especially since indoor number concentrations for multiwall carbon nanotube aggregates is at least 10 times the outdoor concentration, and virtually all gas combustion processes are variously effective sources.These results also raise concerns for manufactured carbon nanotube aggregates, and related fullerene nanoparticles.

View Article: PubMed Central - PubMed

Affiliation: Department of Metallurgical and Materials Engineering, The University of Texas at El Paso, El Paso, Texas 79968, USA. fekberg@utep.edu

ABSTRACT
Nanotechnology and nanomaterials have become the new frontier world-wide over the past few years and prospects for the production and novel uses of large quantities of carbon nanotubes in particular are becoming an increasing reality. Correspondingly, the potential health risks for these and other nanoparticulate materials have been of considerable concern. Toxicological studies, while sparse, have been concerned with virtually uncharacterized, single wall carbon nanotubes, and the conclusions have been conflicting and uncertain. In this research we performed viability assays on a murine lung macrophage cell line to assess the comparative cytotoxicity of commercial, single wall carbon nanotubes (ropes) and two different multiwall carbon nanotube samples; utilizing chrysotile asbestos nanotubes and black carbon nanoaggregates as toxicity standards. These nanotube materials were completely characterized by transmission electron microscopy and observed to be aggregates ranging from 1 to 2 microm in mean diameter, with closed ends. The cytotoxicity data indicated a strong concentration relationship and toxicity for all the carbon nanotube materials relative to the asbestos nanotubes and black carbon. A commercial multiwall carbon nanotube aggregate exhibiting this significant cell response was observed to be identical in structure to multiwall carbon nanotube aggregates demonstrated to be ubiquitous in the environment, and especially in indoor environments, where natural gas or propane cooking stoves exist. Correspondingly, preliminary epidemiological data, although sparse, indicate a correlation between asthma incidence or classification, and exposure to gas stoves. These results suggest a number of novel epidemiological and etiological avenues for asthma triggers and related respiratory or other environmental health effects, especially since indoor number concentrations for multiwall carbon nanotube aggregates is at least 10 times the outdoor concentration, and virtually all gas combustion processes are variously effective sources. These results also raise concerns for manufactured carbon nanotube aggregates, and related fullerene nanoparticles.

Show MeSH
Related in: MedlinePlus