Relationship between redox activity and chemical speciation of size-fractionated particulate matter

Ntziachristos, Leónidas; Froines, John R.; Cho, Arthur K.; Sioutas, Constantinos

doi:10.1186/1743-8977-4-5

Cited by 235 publications

(192 citation statements)

References 48 publications

Supporting

Mentioning

155

Contrasting

Unclassified

Order By: Relevance

“…Stronger associations during the cooler phase of study, despite similar PM 0.25 mass concentrations in cooler and warmer phases, further support the view that the greatest impacts on systemic responses may be attributable to nanoparticles not adequately represented by the present par ticle mass measurements as well as to unmea sured toxic air pollutants that increase near ground level in the winter. Our related experi mental work using particles collected in the LA air basin at the Southern California Particle Center suggests that this might include redox active and electrophilic organic components of traffic exhaust particles in the ultrafine range (Araujo et al 2008;Gong et al 2007;Li et al 2003;Ntziachristos et al 2007;Shinyashiki et al 2008).…”

Section: Resultsmentioning

confidence: 99%

“…Mechanisms involving oxidative stress and inflammation have been proposed to explain these associations (Mills et al 2007) (Figure 1). In addition, a growing toxicol ogy literature suggests that ultrafine particles (UFP), < 0.1 µm in diameter, may have greater potential to induce oxidative stress and inflammation than larger particles that domi nate PM 2.5 and PM 10 mass (Ntziachristos et al 2007). This is likely because compared with larger particles, UFP have a higher air way deposition efficiency, magnitudes higher particle number (PN) concentration and sur face area, and higher concentrations of organic components shown to induce oxidative stress responses (Li et al 2003).…”

mentioning

confidence: 99%

See 1 more Smart Citation

Air Pollution Exposures and Circulating Biomarkers of Effect in a Susceptible Population: Clues to Potential Causal Component mixtures and mechanisms

Delfino¹,

Staimer²,

Tjoa³

et al. 2009

Environ Health Perspect

Self Cite

View full text Add to dashboard Cite

Section: Resultsmentioning

confidence: 99%

mentioning

confidence: 99%

Air Pollution Exposures and Circulating Biomarkers of Effect in a Susceptible Population: Clues to Potential Causal Component mixtures and mechanisms

Delfino¹,

Staimer²,

Tjoa³

et al. 2009

Environ Health Perspect

Self Cite

View full text Add to dashboard Cite

“…Ultrafine particles carry more redox-active components than larger particles, which are more spatially homogenous. 7,31,32 Based in large part on experimental evidence, it has been hypothesized that particles from vehicular exhaust, especially in the ultrafine range, can trigger oxidative stress. When antioxidant responses are then overwhelmed, airway inflammation may follow, leading to increasing asthma symptoms in susceptible children.…”

Section: Overview Of Findings and Implicationsmentioning

confidence: 99%

Repeated hospital encounters for asthma in children and exposure to traffic-related air pollution near the home

Delfino

Chang

et al. 2009

Annals of Allergy, Asthma & Immunology

View full text Add to dashboard Cite

Background: Aggregate hospital encounters for asthma (admissions or emergency department visits) have been associated with daily regional air pollution. There are fewer data on relationships between repeated hospital encounters and traffic-related air pollution near the home.Objective: To estimate the association of local traffic-generated air pollution with repeated hospital encounters for asthma in children.Methods: Hospital records for 2,768 children aged 0 to 18 years (697 of whom had Ն2 encounters) were obtained for a catchment area of 2 hospitals in northern Orange County, California. Residential addresses were geocoded. A line source dispersion model was used to estimate individual seasonal exposures to local traffic-generated pollutants (nitrogen oxides and carbon monoxide) longitudinally beginning with the first hospital encounter. Recurrent proportional hazards analysis was used to estimate risk of exposure to air pollution adjusting for sex, age, health insurance, census-derived poverty, race/ethnicity, residence distance to hospital, and season. The adjustment variables and census-derived median household income were tested for effect modification.Results: Adjusted hazard ratios for interquartile range increases in nitrogen oxides (4.00 ppb) and carbon monoxide (0.056 ppm) were 1.10 (95% confidence interval, 1.03-1.16) and 1.07 (1.01-1.14), respectively. Associations were strongest for girls and infants but were not significantly different from other groups. Stronger associations in children from higher-income block groups (P Ͻ .09 for trend) may have been due to more accurate data.Conclusions: Associations for repeated hospital encounters suggest that locally generated air pollution near the home affects asthma severity in children. Risk may begin during infancy and continue in later childhood, when asthma diagnoses are clearer.

show abstract

“…Previous studies reported strong associations between the PAH content of atmospheric PM samples and DTT (Cho et al, 2005;Ntziachristos et al, 2007b). Biswas et al (2009) measured the chemical composition and redox activity of particles from a variety of diesel engines, and found that there is a strong association between water soluble organic carbon (WSOC), organic acids, and DTT.…”

Section: Pm Volatility and Its Impact On Public Exposure And Healthmentioning

confidence: 99%

Atmospheric Processes Influencing Aerosols Generated by Combustion and the Inference of Their Impact on Public Exposure: A Review

Ning

Sioutas

2010

Aerosol Air Qual. Res.

Self Cite

View full text Add to dashboard Cite

Combustion-generated aerosols, especially emissions of heavy and light duty vehicles, are the dominant contributors of ambient particulate matter (PM) in urban environments. This paper reviews the atmospheric processes (such as dilution, nucleation, condensation and coagulation) that dominate the dynamics of combustion aerosols following their emission, with a particular emphasis on PM from mobile sources. Atmospheric dilution affects the dynamic behavior of aerosols by shifting the gas-particle partitioning of the semi-volatile component of these aerosols. Our paper discusses the roles of dilution in changing the physico-chemical properties of the ambient aerosols, such as particle size distribution and number concentration, and the degree to which it affects non-labile and semi-volatile PM components. This information is complemented with a discussion of secondary aerosol formation from atmospheric photochemical reactions that involve precursors emitted from traffic sources. Special focus is devoted to the role of gas-phase vapors formed from the evaporation of the semi-volatile fraction of aerosols during dilution. Adding to the common recognition that volatile organic compounds (VOCs) are the major gaseous precursors, these vapors also actively participate in photochemical reactions and contribute to the formation of secondary aerosols. Following this discussion, we review recent findings that link PM semi-volatile components and their redox activity, and we discuss the influence and importance of PM volatility on particle toxicity. Lastly, this paper discusses possible metrics to regulate PM emissions and establish ambient air quality standards that are pertinent to public health, and suggests future investigations aimed to improve our current understanding of the adverse health effects of population exposure to combustion-generated aerosols.

show abstract

Relationship between redox activity and chemical speciation of size-fractionated particulate matter

Cited by 235 publications

References 48 publications

Air Pollution Exposures and Circulating Biomarkers of Effect in a Susceptible Population: Clues to Potential Causal Component mixtures and mechanisms

Air Pollution Exposures and Circulating Biomarkers of Effect in a Susceptible Population: Clues to Potential Causal Component mixtures and mechanisms

Repeated hospital encounters for asthma in children and exposure to traffic-related air pollution near the home

Atmospheric Processes Influencing Aerosols Generated by Combustion and the Inference of Their Impact on Public Exposure: A Review

Contact Info

Product

Resources

About