Airway biological toxicological responses
Biomarkers of response and sensitivity to combustion derived aerosols – (Dr Ian Mudway – Environmental Research Group, School of Public Health)
There is a need to better understand the health impacts of ambient aerosols on human health, and particularly to discriminate between the effects of components derived from different sources. In this presentation I will explore differences in human systemic and pulmonary responses in relation to differing combustion derived aerosols – diesel exhaust, biodiesel, wood smoke and aviation derived particulate matter, both generated under experimental conditions and as mixed sources within ambient air. I will also explore the basis of differential sensitivities between individuals and disease groups, as well as potential interventions to reduce adverse responses to air pollutant exposures.
Aerosols in the London Underground – (Michael Hedges – PhD student, Environmental Research Group, School of Public Health.
Underground systems provide an important mode of environmentally friendly urban transportation relieving traffic congestion. However, there are increasing concerns over the elevated levels of particulate matter (PM) concentrations found in the underground and the potential health effects to London Underground (LU) staff and commuters of long-term exposure to underground PM. Concentrations in the underground are elevated beyond ambient levels due to the age, lack of ventilation, train frequency and confined spaces of the underground system. The physio-chemical properties of underground PM are very different to urban PM: being more metal-rich and generated from train wear products, such as the wheel/rail interface and brake wear. Health studies have been inconclusive in identifying the health implications of underground exposure. In-vivo studies have suffered from a lack of power, due to small study populations, and poor selection of outcome measures. In contrast, in-vitro evidence suggests underground PM2.5 can induce increased genotoxicity, inflammatory responses, and oxidative stress in human A549 epithelial cells. Previous studies have indicated that underground transitional metals driving in-vitro redox reactions could be responsible for these biological findings. In my current work we are addressing these knowledge gaps, by characterising the relationship between underground PM2.5 exposure and subsequent health effects by undertaking well-designed measurement campaigns throughout the underground network to be used in health studies. These will characterise the exposure of commuters and staff on the underground to support epidemiological and health-related medical studies to further understanding of the health effects of travel on the London Underground.
Dr Ian Mudway