Linking vehicle emissions to brain health
While the harmful effects of air pollution on lung and cardiovascular health have been widely confirmed, impacts on the central nervous system have been less well studied. The TUBE project sought to address this by examining possible environmental causes of Alzheimer’s disease and other brain-related conditions. “It has been obvious for years that air pollution causes various respiratory and cardiac diseases,” says TUBE project coordinator Pasi Jalava from the University of Eastern Finland. “Recent evidence though also indicates an association between polluted air and neurological disorders.”
Adverse health effects of air pollutants
TUBE brought together a multidisciplinary consortium to answer several key questions on this topic, covering emission research as well as health research. The project began by carrying out measurements in different urban environments, to detect ultrafine particles (UFPs). These were found in every environment, in varying degrees. The contribution of vehicle emissions – and the effect of the aromatic content of fuel on diesel- and petrol-powered vehicles – were also studied. “A major innovation was the inclusion of this state-of-the-art aerosol research with biological research, to study as yet unknown health effects of modern vehicle emissions,” explains Jalava. Project partners examined the adverse health effects of UFPs using cell cultures, as well as human data from an epidemiological cohort study and experimental exposure setting. Researchers looked for inflammatory, cytotoxic and genotoxic changes to confirm whether ultrafine particulate pollution from traffic exhaust may cause a potential risk to human brain health.
Environment risks of ultrafine particles exposure
“One of our most interesting findings was that areas around airports may present a highly significant environment risk of UFP exposure,” says Jalava. “UFPs from vehicles though were also found in the air around streets, highways and harbours.” The project found that fuel aromatic content is a major contributor to the harmfulness of emissions. “Reducing the aromatic content of fuel can reduce emissions even without particulate filters,” notes Jalava. “We also confirmed though that particulate filters can help to reduce emissions from petrol engines.” On the health side of things, the project team confirmed that untreated vehicle emissions can be harmful to the brain. “In particular, smaller UFPs caused higher toxic effects in our cell models,” adds Jalava.
Reducing UFP emissions in urban environments
A key success of the project has been the establishment of a research team capable of carrying out more in-depth studies of air pollution impacts on health, especially brain health. “We have developed some research proposals following completion of this project,” remarks Jalava. “This work will certainly continue in some form.” One issue, Jalava believes, is the lack of robust population-based evidence of the effects of UFPs on brain health. This can be addressed by improving measurement technologies, and widening the coverage of these measurements. Jalava believes that the evidence gathered through the TUBE project will contribute to future legislation designed to reduce UFP emissions and concentrations in urban environments. “We hope that the measurement of UFPs will continue to be improved, to help us gain better population-based evidence of the impact of UFPs,” he adds. “Our results strongly indicate the need for continuing this research on the harmful effects of air pollution on the human brain.”
Keywords
TUBE, vehicle, emissions, brain, health, pollution, Alzheimer’s, neurological
