PM10 levels in communities close to and away from opencast coal mining sites in Northeast England

Concerns about levels of particulate matter of less than 10 μm (PM10) and their potential health effects have been raised by residents living near opencast coal mining sites in the UK. PM10 levels were measured by TEOM in 5 matched pairs of communities in northeast England, 5 near active opencast sites and 5 further away, to characterise the PM10 exposure of residents. 14 609 paired 30-min TEOM readings, and weather data were collected during 1996–97, over 6 weeks each in four pairs and for 24 weeks in one pair. Co-located samplers collected PM10 on an approximately weekly basis and samples were analysed using scanning electron microscopy with energy dispersive analysis (SEM-EDS). The patterns of PM10 levels over time were similar in Opencast and Control Communities and were mostly similar to readings from nearby automated urban network stations. This suggested regional influences on PM10 levels. The geometric mean PM10 was 17.0 μg m−3 in Opencast and 14.9 μg m−3 in Control Communities (arithmetic mean 22.1 μg m−3 in Opencast 18.2 μg m−3 in Control Communities): Opencast Communities thus had 14% higher PM10 levels than Control Communities on average. While the size distribution and proportion of shale particles indicated the opencast site as contributor to the PM10 load in adjacent communities, elevated PM10 levels in Opencast Communities were not positively linked with permitted working hours or wind direction being from the site to the community. No consistent relationship was found between PM10 levels and wind speed or day of the week.