Technical Note: Particulate reactive oxygen species concentrations and their association with environmental conditions in an urban, subtropical climate
Author:
Khurshid S. S.ORCID, Siegel J. A., Kinney K. A.
Abstract
Abstract. Reactions between hydrocarbons and ozone or hydroxyl radicals lead to the formation of oxidized species, including reactive oxygen species (ROS), and secondary organic aerosol (SOA) in the troposphere. ROS can be carried deep into the lungs by small aerodynamic particles where they can cause oxidative stress and cell damage. While environmental studies have focused on ROS in the gas-phase and rainwater, it is also important to determine concentrations of ROS on respirable particles. Samples of PM2.5 collected over 3 h at midday on 40 days during November 2011 and September 2012 show that the particulate ROS concentration in Austin, Texas ranged from a minimum value of 0.02 nmol H2O2 (m3 air)−1 in December to 3.81 nmol H2O2 (m3 air)−1 in September. Results from correlation tests and linear regression analysis on particulate ROS concentrations and environmental conditions (which included ozone and PM2.5 concentrations, temperature, relative humidity, precipitation and solar radiation) indicate that ambient particulate ROS is significantly influenced by the ambient ozone concentration, temperature and incident solar radiation. Particulate ROS concentrations measured in this study were in the range reported by other studies in the US, Taiwan and Singapore. This study is one of the first to assess seasonal variations in particulate ROS concentrations and helps explain the influence of environmental conditions on particulate ROS concentrations.
Publisher
Copernicus GmbH
Reference59 articles.
1. Arellanes, C., Paulson, S. E., Fine, P. M., and Sioutas, C.: Exceeding of Henry's law by hydrogen peroxide associated with urban aerosols, Environ. Sci. Technol., 40, 4859–4866, 2006. 2. Ayers, G. P., Penkett, S. A., Gillett, R. W., Bandy, B., Galbally, I. E., Meyer, C. P., Elsworth, C. M., Bentley, S. T., and Forgan, B. W.: Evidence for photochemical control of ozone concentrations in unpolluted marine air, Nature, 360, 446–449, 1992. 3. Baulig, A., Poirault, J.-J., Ausset, P., Schins, R., Shi, T., Baralle, D., Dorlhene, P., Meyer, M., Lefevre, R., Baeza-Squiban, A., and Marano, F.: Physicochemical characteristics and biological activities of seasonal atmospheric particulate matter sampling in two locations of Paris, Environ. Sci. Technol., 38, 5985–5992, 2004. 4. Bell, M. L., Samet, J. M., and Dominici, F.: Time-series studies of particulate matter, Annu. Rev. Publ. Health, 25, 247–280, 2004. 5. Boogaard, H., Janssen, N. A. H., Fischer, P. H., Kos, G. P. A., Weijers, E. P., Cassee, F. R., van der Zee, S. C., de Hartog, J. J., Brunekreef, B., and Hoek, G.: Contrasts in oxidative potential and other particulate matter characteristics collected near major streets and background locations, Environ. Health Persp., 120, 185–191, 2012.
|
|