Agenda item

Alex Bullied updated the Board on progress with a pilot study into the exposure of Exeter residents to ultra-fine particles (PM_2.5).

The pilot conducted in June and July 2015 involved three volunteers equipped with personal PM_2.5 monitors and GPS loggers for 24 hours while they conducted their normal activities. The project mapped the exposure of the volunteers by location, and plotted exposure against time and activity. It provided personal travel planning advice to the volunteers and used their monitoring data to suggest changes they could make which would reduce their exposure. The volunteers had been chosen as they travelled from a variety of home locations as set out below, and to test different potential options for alternative sustainable travel choices.

Previous studies in London and other cities had shown that daily patterns of exposure were personal to individuals, and that reductions could be achieved by changing travel habits.

Results showed that, for car journeys, the route was important in determining the exposure to ultra fine particles. For example, Volunteer 1 travelling between Cranbrook and Exeter normally by car, but on different roads in the morning and afternoon. Their exposure was higher when travelling via East Wonford Hill and Heavitree Road than via Pinhoe Road. For Volunteer 2, measured concentrations also varied with route. For this person it was not possible to suggest a realistic alternative travel mode other than to change the route used for her car commute. Her alternative route followed back roads rather than main roads, which allowed her to maintain a more constant speed and more efficient driving style.

Volunteer 3 was able to choose a sustainable travel mode (bike from Lympstone) for their second day of testing and this did result in lower exposure than the car commute (Table 4, Figures 3 and 4). However for Volunteer 1, who changed to bus, the average exposure on the second day was higher than in a private car - the bus from Cranbrook travelling along the main Heavitree corridor and the maximum exposure for this journey was similar to maximum exposure along the same route at a similar time of day in a car.

The pilot study showed that differences in particulate concentration between travel modes could be shown for some individuals, but were not always clear-cut and the sustainable travel message derived from the data was more subtle and nuanced than was apparent from data from similar studies in London. However in public health terms, all three volunteers could achieve a reduction in their daily exposure by behavioural change.

The next priority for the project would include a social marketing budget so that the outputs from the project could be used to maximum benefit. Public Health Devon had agreed to assist with this aspect and the techniques to be used were being developed further.

A separate project was being conducted using a Public Health Devon grant focusing on air pollution. The money would support two projects, one of which was a personal exposure monitoring study with groups of three school children from Braunton, Newton Abbott and Exeter. The study would follow essentially the same methodology but would focus on travel to schools in areas that had been identified as having higher air pollution levels.

RESOLVED that the progress report be noted.