Air Quality Monitoring: Evolving Issues and New Technologies
Monday 12th & Tuesday 13th December 2016
Conference held at the Society of Chemical Industry, 14-15 Belgrave Square, London, SW1X 8PS
Conference Report by Karl Ropkins – University of Leeds
Monitoring Ambient Air (MAA) 2016 was a two-day conference organised by the Royal Society of Chemistry’s Automation and Analytical Management Group (AAMG). Over 80 delegates, including both attendees and speakers from the United Kingdom, elsewhere in Europe, and North America, met for the conference which included six sessions, twenty presentations, seven posters and three exhibits.
The conference was opened by AAMG Hon. Secretary Dr Alan Braithwaite, who spoke about the origins of MAA, which began as a more specialist thermal desorption workshop, and its rapid growth to incorporate a much wider range of analytical challenges and technical solutions.
Session 1: Paul Quincey chaired ‘Innovative Measurement Technologies’, the opening session which introduced three very timely presentations. Firstly, Stephen Stratton of Ricardo Energy & Environment and Margaret Bell of University of Newcastle presented an overview of the findings of the Defra commissioned ‘Investigating the Feasibility of Innovative Technologies to Improve Air Quality Monitoring over the Medium to Long Term.’ The report and presentation focused on the viability and market barriers for four classes of monitoring technology, satellite-based remote sensors, aircraft and ground-based remote sensors, pervasive sensors, and fixed-point sensors, identified as having the potential ability to meet Defra’s medium to long-term (10-15 years) UK ambient air monitoring requirements. The second presentation was by J. Stewart Hager, of HEAT, the US company developing and commercialising EDAR, a new-to-market passing vehicle emission measurement system employing Differential Absorption LIDAR (DiAL). The EDAR has recently been evaluated in the US and UK and Stewart’s presentation ‘Laser based remote sensing of vehicle exhaust’ focused on the science underpinning the technology and the extra insights that are possible using DiAL rather than conventional adsorption spectroscopy. David Worton of the National Physical Laboratory (NPL) UK closed the session with ‘Developments in technologies and accuracy for NOx measurements’, an overview of the NPLs recent work on direct NO2 measurement methods and calibration standards. The existing air monitoring regulatory standard estimates NO2 as the difference between NO and NOx measured by chemiluminescence, and this work could provide the basis for new regulations for the direct measurement of the species that is arguably the UK’s current priority air quality pollution issue.
Session 2: The second session, ‘Particulate Measurements: Ultrafine and Composition’, was chaired by Gary Fuller of King’s College London. Particulates are an on-going concern, and Gary spoke briefly as part of his introduction about international efforts to better understand the most complex of the priority pollutants. In the first presentation of the session, ‘Long-term measurements of ultrafine particles in the Ruhr area (Germany)’, Ulrich Quass of the German Institute of Energy and Environmental technology (IUTA) described their work using instruments deployed at sites within the German Ultrafine Aerosol Network (GUAN) to study the relationship between particle number, surface area and mass, their sources and short-term health effects. Then Brian Stacey of Ricardo Energy & Environment presented an update on his efforts in collaboration with Heathrow Airport Limited and University of Birmingham to characterise ultrafine particulate (UFP) in and about Heathrow Airport titled ‘UFP Monitoring at Heathrow Airport’. Brian highlighted international concerns about airport-related UFP sources, datasets now being collected and objectives for upcoming data analysis. In the third presentation of the session, ‘Taking Ambient Air Monitoring to the Next Level’, Frederik Weis of specialist particulate analyser developer Palas GmbH (Germany) described the Fidas® range of sensing technologies and their applications for ambient particulate measurement. Frederik emphasised the broad range of metrics the patented technology reported, from conventional measures such as PM10 and PM2.5 through fine and ultrafine particulate and particle number. Speaking fourth, Olivier Favez of Institut National de l'Environnement (INERIS; France) presented ‘Characterisation of PM Pollution Within the French CARA Program’. Olivier described strategies for the discrete measurement of airborne aerosols derived from multiple sources and highlighted the value of such work by providing evidence of the role of agricultural NH3 emissions in the generation of ammonium nitrate pollution episodes. In the final presentation of the session, David Green of King’s College London spoke about ‘Chemical Composition Measurements and Source Apportionment of PM10 at Port Talbot’, the UK’s largest steelworks. David described the mobile monitoring laboratory set up on site, its measurement capabilities and presented the outcomes of recent source apportionment work that pointed to a complex mix of site-related sources (blast furnaces, coke ovens, solid fuel burning, etc.) and off-site sources (marine, traffic, etc.) driving local airborne particulate levels.
Session 3: The third session, ‘Small Sensors’, chaired by Paul Monks of the University of Leicester, was the first of two smaller sessions led by the Air Quality Expert Group (AQEG), and included three very different presentations highlighting the diverse nature of contemporary sensor-related research. Rod Jones of University of Cambridge opened the session with ‘Using a Commercial Low-cost Sensor Network (AQMesh) to Quantify Urban Air Quality: Comparing Measured and Modelled (ADMS urban) Pollutant Concentrations’. Rod presented data comparing sensor and conventional (AURN) air pollutant measurements, demonstrating encouraging agreement and citing the AURN ratification process as a possible source of errors for such studies. He also emphasised the potential benefits of integrating sensor network data within modelling procedures. Then Joris van den Bossche of Vrije Universiteit Brussel presented ‘The CurieuzeNeuzen Citizen Science Project: Large-scale Air Quality Mapping of NO2 Concentrations in Antwerp, Belgium’, work that used crowd-sourcing to both deploy a sensor network across a city at very low costs and to engage with the local community. Alastair Lewis of the University of York provided the last talk of session. ‘Application of Low-cost Sensors in Air Pollution Monitoring’ was a high-level discussion of sensor technologies, their current uptake patterns and barriers to wider use, that provided an interesting counterpoint to earlier presentations. There was also the hint that maybe we are still not making best use of the sensor technologies already available to us?
Session 4: The second AQEG-led session, also chaired by Paul Monk (University of Leicester), focused on ‘Agricultural Emissions’ and also included three presentations. The first ‘Agricultural Emissions, their Contribution to Air Quality and the Likely Value of Control Measures’ by David Fowler of the NERC Centre for Ecology and Hydrology (CEH) provided a comprehensive overview of agricultural emissions of ammonia, methane and N2O in the UK. As part of his discussion of inventory estimates and control measures, David noted that ammonia emissions, of which agricultural sources account for over 80%, have declined little in recent years while agricultural sources of other species are less confidently quantified but are likely to have increased over the same period. Then Christine Braben, also of NERC CEH, talked about recent PM pollution events widely reported as a Saharan dust plume by the UK media. In a presentation entitled ‘The UK Particulate Episode of March-April 2014: More Than Saharan Dust’, Christine showed that the chemical evidence indicated a large ammonium nitrate contribution to that episode, suggesting agricultural and other sources. Jacob Mønster of Danish company FORCE Technology closed the sessions with ‘Low-cost Sensor for Continuous Monitoring of the Ammonia Emission from a Pig House’, a presentation on work undertaken by FORCE and the Danish Technological Institute to develop routine ammonia emissions monitoring systems for use on pig farms. The presentation included discussion of a novel electrochemical ammonium sensor with regenerative capabilities that significantly extending its operational lifetime and performance by comparison to conventional alternatives.
Session 5: The fifth session ‘Exposure Reduction – Photocatalytic Paints’ included two presentations, ‘Photocatalytic Solutions to Mitigate Local Pollution Problems’ by Robert McIntyre of UK company Cristal Global and ‘Development of More Durable Photocatalytic Coating for Pre-Coated Metal’ by Chandrakant Mistry of UK company Becker Industrial Coatings. Although the shortest of the workshop sessions, these two presentations provided an interesting indication of the scope of work in this field, focusing on the development of surface coatings that actively breakdown dirt and air pollutants. Robert’s presentation provided an overview of Cristal Global’s work on the development of more effective photocatalytic paints, while Chandrakant’s presentation provided a similar overview of Becker Industrial Coating’s work to maximise the active life-times of such materials.
Session 6: I had the privilege of chairing the sixth and final presentation sessions of the workshop, ‘New Techniques and Recent Developments’. The first presentation of the session, ’Controlling Air Pollution at Construction Sites’, was made by Gary Fuller of King’s College London. Gary provided an overview of recent work to characterise construction-related emission in London, which was declared the first Low Emission Zone for construction machinery in 2014. Gary’s presentation also included an assessment of current monitoring methods and threshold levels used as part of on-site dust management programmes. Stephan Leinert of the North Rhine-Westphalian State Agency Landesamt für Natur Umwelt und Verbraucherschutz Nordrhein-Westfalen (LANUV) provided the second presentation on a ‘New Method for the Measurement of Engineered TiO2 Nanoparticles.’ Here, Stephen discussed the challenges of measuring industrially engineered nanoparticles in an environment dominated by high levels of naturally produced UFP, and an instrumental method to monitor chemically unique nanoparticle emissions from a factory producing paint pigments. Nuria Camiña of King’s College London then presented ‘On-Filter Determination of Particulate Matter Oxidative Potential: A Seasonal Analysis of the London Particulate Airshed.’ Nuria discussed both the need for and analytical complexities of PM filter based oxidative potential measurement, and presented a time-series analysis of measurements from four sites across London that indicated both an oxidative potential urban increment and winter maximum. The final presentation of the session and workshop was ‘Combination of Plant Monitoring Results and Weather Data as a Method to Identify PCB-Sources’ made by Dieter Gladtke of LANUV (Germany). In a talk that provided an interesting counterpoint to earlier presentations that focused on source apportionment of highly mobile airborne species, Dieter spoke about methods for source apportionment of more persistent pollutants, here focusing on the use of curly kale as a bioindicator, spatial sampling, and back-trajectory analysis to identify an electrical waste recycling facility (or more specifically its shredder unit) as a likely source of PCBs in one area.
Exhibitions, including live instrument demonstrations, were hosted by Air Monitors (http://www.airmonitors.co.uk/), Enviro Technology Services (http://www.et.co.uk/) and Hager Environmental & Atmospheric Technologies (HEAT; http://heatremotesensing.com/).