Field Measurements and Source Analysis of Airborne Particulate Matter in London

Student thesis: Doctoral ThesisDoctor of Philosophy


Datasets of PM10 measured gravimetrically and its key components from different locations (background, suburban, roadside, kerbside) in London during the period 2001 to 2012 have been collected and analysed. During this period a number of regulatory requirements and other initiatives, including a Low Emission Zone, were introduced targeting the reduction of PM10 because of its known adverse health effects. Analysis across the whole timescale was confounded by a change of filter substrate in 2007 but no evidence of any noticeable reduction in overall PM10 concentrations was found at the study sites. The contribution of the coarse fraction increased at Marylebone Road suggesting that road abrasion and brake and tyre wear from traffic sources became increasingly important. Pollution episodes, when PM10 concentrations exceeded 50 μg m-3, were particularly noticeable in springtime and associated with increased ammonium nitrate concentrations. Ammonium sulphate concentrations reduced by approximately 30% at the time of the introduction of ultra-low sulphur fuel in the UK in 2007 signifying the importance of local sources of sulphate to PM10 concentrations. A high concentration (6.5 μg m-3) of chloride in the fine fraction of PM10 at one of the sites in early November suggests that not all chloride concentrations may be associated with sea-salt and that anthropogenic chloride can make a significant contribution to pollution episodes.

Particulate black carbon from vehicle emissions has independently been linked to adverse health outcomes. The use of transmissometry and reflectometry to measure and compare the light absorbing properties of equivalent black carbon concentrations (EBC) on archived filters of different substrates was investigated. Equations for calculating daily EBC concentrations were determined and may be used at locations where measurements would not otherwise be available. A decrease in the region of 7% in overall mean EBC concentrations was detected at Marylebone Road after 2010. However, daily concentrations at all locations did not change in line with PM10 concentrations indicating a need for a separate long term monitoring programme of ambient EBC concentrations to track the results of exhaust abatement technologies and policies.
Date of Award2014
Original languageEnglish
Awarding Institution
  • King's College London
SupervisorGary Fuller (Supervisor) & Steven Smith (Supervisor)

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