2011 Haagen-Smit Prize Winners
The Executive Editors and the Publisher of Atmospheric Environment take great pleasure in announcing the 2011 ''Haagen-Smit Prize'', designed to recognize outstanding papers published in Atmospheric Environment. The Prize is named in honor of Prof. Arie Jan Haagen-Smit, a pioneer in the field of air pollution and one of the first editors of the International Journal of Air Pollution, a predecessor to Atmospheric Environment.
The ''Haagen-Smit Prize'' is given annually to two papers previously published in Atmospheric Environment and covering different science areas. Additional information about this award and the selection committee members can be found at http://geo.arc.nasa.gov/sgg/singh/. The nominating letters printed below describe the two 2011 winning papers.
J. Calvert and S. Lindberg. Mechanisms of mercury removal by O3 and OH in the atmosphere. Atmos. Environ., 39, 3355-3367, 2005.
It is a pleasure to nominate the Calvert and Lindberg 2005 Atmospheric Environment paper for the 2011 Haagen-Smit Prize. This paper examined the mechanism for oxidation of Hg(0) to Hg(II), a critical step for atmospheric deposition of mercury. It was written at a time when the conventional view, based on a few lab studies and reflected in all mercury models, was that oxidation of Hg(0) in the global troposphere took place in the gas phase with OH and ozone as the main oxidants. Calvert and Lindberg blew the whistle by pointing out that these lab studies were likely contaminated by surface processes and that gas-phase oxidation of Hg(0) by OH and ozone was in fact unlikely to occur at a significant rate in the atmosphere. This has led to a fundamental re-evaluation of our understanding of atmospheric mercury chemistry, and has stimulated research to identify alternative Hg(0) oxidants. There are now a few working hypotheses, although large uncertainties remain. The Calvert and Lindberg paper marks a turning point for mercury research and will have a lasting impact. The paper has been cited nearly 70 times and is highly deserving of the Haagen-Smit Prize.
Nominator: Daniel Jacob, Harvard University, USA
Dr. Jack G. Calvert, 12665 Amberset Drive, Knoxville, TN 37922 (JGCalvert@charter.net)
Dr. Steve Lindberg, 35 Wishram Trail, Graeagle, CA 96103 (Lindberg@PSLN.com)
Y. F. Zhu, W. C. Hinds, S. Kim, S. Shen and C. Sioutas. Study of ultrafine particles near a major highway with heavy-duty diesel traffic. Atmos. Environ., 36, 4323-4335, 2002.
Zhu et al. (2002) reported measurements of ultrafine particles downwind of the Interstate 710 freeway in Los Angeles. This highway, on which 25% of the traffic is heavy-duty diesel trucks, is one of the most heavily traveled in the nation. This paper was ground-breaking in obtaining data on the particulate air quality, especially particle number concentrations, in the vicinity of a major roadway containing substantial diesel traffic and has been cited more than 300 times since its publication.
Abundant epidemiological literature has indicated a significant relationship between ambient particulate matter (PM) and gas phase pollutants and important clinical endpoints, such as respiratory symptoms (including asthma attacks), cardiovascular morbidity, and mortality. In air pollution control, national concerns are currently dominated by the effects of PM on public health. However, the underlying biological causes of the health effects of PM exposure are unclear. For example, it is not clear whether the mass concentration or the number concentration is most important in causing these adverse PM health effects. The particle size of airborne PM controls where inhaled particles deposit in the various regions of human respiratory system by the complex action of aerosol deposition mechanisms. Most recent toxicological studies have shown that ultrafine particles are more toxic than larger particles with the same chemical composition and at the same mass concentration. Currently, however, only the mass of particulate matter less than 10 µm in aerodynamic diameter (PM10) and less than 2.5 µm (PM2.5) are regulated. Information about ultrafine particles is usually not available. In fact, even though ultrafine particles represent over 80% of particles in terms of number concentration in an urban environment, the less numerous but much heavier supermicron particles dominate mass concentration measurements. Thus, number concentration, together with the size distribution of ultrafine particles, is needed to better understand ambient air quality and its potential health effects. In an urban environment, motor vehicle emissions usually constitute the most significant source of ultrafine particles. Although traffic-related air pollution in urban environments has been of increasing concern, most studies have focused on gaseous pollutants, and total mass concentration and chemical composition of particulate pollutants. Since the majority of particles from vehicle exhaust are in the ultrafine size range it is important and necessary to quantify ultrafine particle emission levels, and to determine ultrafine particle behavior after emission as they are transported away from the emission source --- busy roads and freeways.
Results from this study showed that the maximum ultrafine particle number concentration observed near the freeway was about 20 times greater than that for the background location. It suggests that people, who drive on the freeways or who live, work, or travel near major traffic sources, will have much higher ultrafine particle exposure than those who live farther away from such sources. This paper represents one of a serial of studies conducted by Dr. Zhu and colleagues to characterize ultrafine particles in the vicinity of major highways, particularly as they are transported downwind from the freeway. This paper provided important data on ultrafine particle concentrations near roadways for use in exposure studies and spurred a number of subsequent urban roadway measurements worldwide. This paper was also cited in major regulatory documents such as the U.S. EPA’s “Criteria Document for Particulate Matter” and the California Air Resource Board’s “Ambient Air Quality Standards for Particulate Matter and Sulfates” document and ultimately led to California Senate Bill 352 that prohibits building any new school site within 100 m from major roadways. This paper is highly deserving of the Haagen-Smit Prize.
Nominator: Jamie Schauer, University of Wisconsin-Madison, USA
Prof. Yifang Zhu, UCLA School of Public Health 51-295 CHS, Los Angeles, CA 90095 (Yifang@ucla.edu)
Our congratulations go to the authors of the two outstanding papers selected for the 2011 Prize. We would also very much like to thank all the nominators for their effort and note that unsuccessful nominations are eligible for consideration again next year. We further take this opportunity to acknowledge the conscientious effort of the selection committee, made up of members from five countries, in arriving at a clear and timely decision.
Hanwant B. Singh, Peter Brimblecombe, and Chak Chan