In Search of Science
Seeking a greater scientific understanding of the atmospheric factors that contribute to the formation of ground-level ozone pollution - sometimes referred to as "smog" - is the ambitious goal of an organization known as the North American Research Council on Tropospheric Ozone, or NARSTO.
Sharing this objective of greater scientific understanding - and working to forge new directions in thinking on the part of agencies that set air-quality standards and regulations - is NARSTO's recently appointed co-chairman, Robert Wendoll of Dunn-Edwards Corp.
Wendoll, who in the past gained a reputation as one of the coatings industry's most strident critics of national and state air-quality rules that targeted VOCs in architectural paints, was recently elected to a two-year term as the Private Sector co-chairman of the NARSTO Steering Committee. Wendoll, director of Environmental Affairs for Dunn-Edwards, will begin his term Jan. 1, 2002, succeeding Howard Feldman of the American Petroleum Institute. Joining Wendoll in leading the Steering Committee is the Public Sector co-chairman, James Meagher of the U.S. National Oceanic & Atmospheric Administration (NOAA).
NARSTO is a public-private research consortium involving the governments of the United States, Canada and Mexico, and also includes representatives of industry, academia, and private research groups. Dunn-Edwards, based in Los Angeles, is a major regional manufacturer and distributor of architectural coatings in California and several other western states. The company is a strong supporter of NARSTO's VOC-reactivity research program.
In a reflection of what might be termed a softening of Dunn-Edwards' former hard-line stance on any VOC regulations affecting architectural and industrial-maintenance (AIM) coatings, Wendoll in recent years has assumed a decidedly lower-key posture in debates about VOC rules. But neither he nor Dunn-Edwards has lost an ounce of their interest in campaigning for science-based air-quality policies - specifically, rules that take into account increased knowledge about ground-level ozone pollution and its causes.
In this regard, NARSTO and Wendoll are the ideal fit. And Wendoll is assuming a leadership position with the organization at a time when NARSTO is undertaking research projects that could generate new approaches to how VOCs are regulated. The organization has commissioned studies on the issue of relative reactivity of VOCs - differences in the propensity of specific compounds to react with other atmospheric pollutants to create ground-level ozone pollution - and a related issue called "atmospheric availability." The discussion of "availability" centers on the extent to which any given VOC may become available in the atmosphere to participate in ozone-forming reactions.
In an announcement regarding his appointment, Wendoll said it is Dunn-Edwards' hope that "future regulatory policies acknowledging reactivity and availability criteria will be far more efficient than current mass-based regulations."
The subject of relative VOC reactivity has attracted a fair degree of attention in the coatings industry, and has actually been incorporated in one existing regulation - California's statewide aerosol VOC rule. This matter of VOC "availability" may not be as well known but, as Wendoll points out, has figured in air-quality rulemaking deliberations involving other products that are sources of VOC emissions.
In fact, a recently enacted national regulation on VOCs in consumer products exempts certain compounds from reporting requirements based on very low vapor-pressure levels - 0.1 millimeters of mercury at 20degC. or less. Such low-volatility compounds, the EPA said, "evaporate at such a low rate that they do not enter the air to any appreciable degree." In other words, they are "unavailable" to react with other compounds to form ozone.
No such exemption exists among VOC regulations affecting coatings, although some VOCs used in coatings would fall below the vapor-pressure threshold included in the consumer-products regulation, Wendoll says.
During a recent interview, Wendoll explained that the atmospheric availability of VOCs to combine with nitrogen oxides and form ozone can be affected significantly by the VOC's "removal" from the atmosphere by absorption or deposition. For example, he said, VOC absorption by water, vegetation or the ground can prevent the VOC from being present long enough to be a reactivity factor. Included in the types of VOCs that can be absorbed this way, he said, are solvents such as ethylene glycol, propylene glycol and Texanol (ester alcohol) - common coalescent solvents in coatings that are easily absorbed by water.
Research Could Cast Doubt on Effectiveness For industries such as coatings manufacturing, this science of reactivity and availability could, in theory, translate into the development of a new breed of air-quality regulation - rules based not strictly on "mass-based" VOC controls that aim simply to reduce total VOC emissions, but controls that would treat specific compounds differently, based on their actual contribution - or lack of - to ground-level ozone pollution.
of Existing 'Mass-Based' VOC Rules
Before any such new-age regulations can emerge, however, there is the trifling matter of empirical evidence - demonstrating how such reactions do or do not occur and the types of atmospheric conditions that are at work. That's where NARSTO can play a significant role, Wendoll says.
A year ago, NARSTO issued a report called "An Assessment of Tropospheric Ozone Pollution," which reviewed progress in the scientific research on ozone-related air-quality problems. The report raised the question of whether reactivity-based controls on VOC emissions may be more effective than so-called "mass-based" controls, particularly in reducing ozone levels in urban areas.
NARSTO also created a panel called the Relative Reactivity Working Group, which was given a mission "to develop policy-relevant science to guide decision-making on how to regulate VOCs most effectively," Wendoll said.
In response to this charge, the reactivity working group has commissioned research that will analyze solvent reactivity under various air-quality scenarios. In part, the research is intended to determine "whether VOC reactivity reduction, independent of mass VOC reductions, in itself can be an effective technique for eliminating ozone formation," Wendoll said.
Research teams retained by NARSTO include some of the most noted experts on VOCs and ground-level ozone pollution in the country, including groups headed by William Carter of the University of California-Riverside, Ted Russell of the Georgia Institute of Technology, and Harvey Jeffries of the University of North Carolina. Wendoll calls them "the world's foremost authorities on the issue of VOC reactivity."
In one research project already under way, Carter is leading an effort to build a so-called "next-generation" smog chamber that is designed to more accurately assess the reactivity of various VOCs. The chamber, when completed in the next year, is expected to duplicate "real-world" atmospheric conditions more accurately than existing instruments. While NARSTO was not directly involved in the launch of the project, Wendoll said the organization will seek to use its findings in its research efforts. Dunn-Edwards played a key role in securing a federal EPA grant that is funding the smog-chamber project, he said.
The earliest findings from NARSTO's other research projects are anticipated within nine months to a year. At the very least, it is hoped that the results "will tell whether it is worth pursuing more research on reactivity" and give an idea "whether reactivity is useful as a regulatory tool," Wendoll said.
It is also believed that additional study will generate greater credibility for the argument that simply forcing lower VOC limits on coatings products across the board may not deliver the desired result. And the U.S. EPA, which has been reluctant to give the issue much attention, is a primary target of the research program. "The EPA is looking for more (scientific) support" of reactivity-based controls. Wendoll said. "They are still the 800-pound gorilla."
Wendoll believes NARSTO's work is already paying off, in part because the group includes key players from industry, science and government. He points out that industry and regulatory agencies are teaming up to provide funding for an in-depth NARSTO modeling assessment of VOC reactivity. The funding sources include the American Chemistry Council, the U.S. EPA, the California Air Resources Board, the Consumer Specialty Products Association, and the National Paint & Coatings Association (NPCA). Dunn-Edwards is providing $25,000 for the project.
"I feel the group is making real progress. For the first time, we've got all the right players at the table," Wendoll said of NARSTO.
And the research could be important to more than manufacturers and users of architectural and industrial-maintenance coatings. "It could have broad application to all types of coatings and consumer products," Wendoll said.