Measurable health risks after brief exposure to exhaust fumes
Epigenetic changes can be detected in the blood of test subjects within two hours of exposure to exhaust fumes. Each of the observed changes are associated with diseases known to be caused by long-term exposure to air pollutants. These were the results of a study conducted by Maastricht University (UM) in collaboration with Imperial College and King's College in London. The international research team recently published its findings in the scientific journal Environment International.
As part of the study, 24 test subjects spent one to two hours on the busy Oxford Street in the centre of London, which has a large number of diesel buses and taxis. Each of the test subjects was equipped with a backpack with sensors and data processors (see photo). Three weeks later, the same group spent the same amount of time in the traffic-free Hyde Park in the British capital. After each visit, the research team – including UM researcher Julian Krauskopf – took blood samples from the participants, which revealed that 54 microRNAs were affected after just two hours of exposure. These microRNAs, or epigenetic particles, are associated with a wide range of health risks. The particles are coded by our DNA and can be influenced by diseases and environmental factors.
MicroRNAs were first discovered in 1993 and have generated considerable scientific interest in recent years as promising biomarkers for organ disease. Circulating microRNAs reflect the adverse consequences of traffic pollution-induced toxicity in organs like the lungs, heart, kidneys and brain. The research team identified 54 microRNAs after two hours of exposure to diesel fumes that are associated with specific types of air pollution, such as black carbon, ultrafine particles and nitrogen dioxide (NO2). 'Our research reveals that even short-term exposure to traffic pollution can pose a significant health risk,' says Julian Krauskopf. 'And not in general terms either; during the study we estimated the health risks associated with personal exposure to everyday traffic-related air pollution.'
Krauskopf's research team is part of the international project EXPOsOMICS, which aims to make predictions about individual health risks in relation to environmental impact. In addition to UM, King's College and Imperial College, the international project also includes the universities of Utrecht, Hasselt, Berkley (USA) and the Institute for Global Health in Barcelona. Oxford Street can be compared to any busy street in a Dutch city and the researchers now want to investigate the results of heavier air pollution. Follow-up research is currently being conducted in Barcelona, where test subjects are being monitored at two highly-polluted areas. The results of that study are expected soon.