In a study that analyzed relationships between air quality and unemployment levels, a Tufts University researcher has developed a new statistical model that retrospectively estimates air pollution exposure for previous time periods where such information is not available.
Mary Davis, an associate professor of urban and environmental policy and planning at Tufts University School of Arts and Sciences, analyzed traffic-related air pollution levels and unemployment rates in four separate regions of California for which extensive air monitoring data was available: San Francisco Bay, Sacramento Valley, San Joaquin Valley, and the south-central coast between 1980 and 2000.
Davis focused on predicting trends in pollutants that are emitted by engines and known to negatively impact human health—haze, carbon monoxide, and nitrogen dioxide. She integrated into her model other variables such as weather, population density, unemployment levels, and environmental regulations. Air pollution data came from the California Air Resources Board.
The unemployment data was provided by the federal Bureau of Labor Statistics. It showed broad shifts in overall unemployment with highs in the early 1980s and 1990s. Unemployment levels for the trucking industry, which were tracked separately, matched the overall trend.
Davis's analysis revealed a pattern. During the highest periods of unemployment—early 1980s and early 1990s—concentrations of the three pollutants decreased in small but discernible amounts for every one percent increase in unemployment. The reason for the decrease, she says, was due to slowdowns in commercial trucking and car trips to work, shopping malls, or recreational destinations.
Importantly, Davis says the model allows epidemiologists to look backwards in time to predict public exposure to pollution in a geographical area. This data would ultimately help researchers discern public health trends.
"We can retrospectively estimate exposure levels for previous periods where direct data is lacking," says Davis, author of the paper titled "Recessions and Health: The Impact of Economic Trends on Air Pollution in California," which will be published in the October issue of the journal "American Journal of Public Health" (available online on August 16). "Without an accurate and historically relevant exposure model it is difficult to obtain estimates of lifetime human exposure which is critical in studies of chronic disease," she adds.
As an example of how the model could be used, Davis applied her formula to the years between 2006 and 2010—when unemployment rose from 4.9 percent to 12.4 percent in California. According to the model, there would have been a 16.8 percent decline in ambient concentrations of carbon monoxide and a 12.2 percent decline in concentrations of nitrogen dioxide.
Her findings were not independently validated but Davis says that "the comparison provides perspective on what the predicted change in air pollution would be during a major economic downturn based on the results of the model."
Davis also looked for relationships between unemployment in the trucking industry and air quality. With trucking, she included estimates for haze, which is a marker for diesel-powered truck emissions. Here, she found a similar pattern of lower predicted pollution levels between 2006 and 2010.
Davis says that the results of her work provide evidence linking the economy to air pollution. In a 2010 study of air pollution levels and economic trends in New Jersey between 1971 and 2003, Davis found a similar relationship between pollution and unemployment.
"This is evidence that cyclical economic activity has an impact on concentrations of pollutants that the general public is exposed to," says Davis. "There is a net benefit for public health in terms of air pollution when unemployment rises."
In the context of environmental policy, Davis suggested that environmental regulating agencies should consider the relationship between air quality and unemployment as they evaluate the effectiveness of clean air regulations. "Air quality regulations have an impact but they don't happen in a vacuum," she continues. "Policies aimed at improving air quality may act to speed up or slow down the underlying trend set by the economy."
Davis, who is participating in a National Institutes of Health-funded study of the trucking industry, air pollution and cancer rates with a team of Harvard University scientists, said the methodology she used in this research could be applied to other regions of the country where data is available.Davis ME. Recessions and Health: The Impact of Economic Trends on Air Pollution in California. Am J Public Health. 2012; 102(10):1951-1956
Alex Reid | EurekAlert!
Diagnoses: When Are Several Opinions Better Than One?
19.07.2016 | Max-Planck-Institut für Bildungsforschung
High in calories and low in nutrients when adolescents share pictures of food online
07.04.2016 | University of Gothenburg
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.
In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...
'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.
Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
21.10.2016 | Health and Medicine
21.10.2016 | Information Technology
21.10.2016 | Materials Sciences