Is Hourly Particulate Matter Sampling the Answer to Burning Questions in Modelling and Health?

Transcription

1 Is Hourly Particulate Matter Sampling the Answer to Burning Questions in Modelling and Health? 1 Andreas Markwitz, Travis Ancelet, Perry Davy and Bill Trompetter BAQ 2012, December

2 Introduction 2 Particulate matter (PM) pollution is a global health concern Adverse health effects related to both particle size and composition In New Zealand alone, it has been estimated that PM pollution (from all sources) causes over 2300 premature deaths, with total social costs of over $8 billion each year Understanding the composition and sources of PM is crucial for developing targeted mitigation strategies to improve health outcomes APM source contributions (emissions) Pressure State Ambient APM concentrations Policy intervention Response APM emission reduction strategies

3 Capabilities 3 At we have been analyzing the elemental composition of PM collected on filters for more than a decade Use Ion Beam Analysis techniques (PIXE, PIGE, PESA, RBS) Able to analyze ~100 filters per day

4 Filter samples are simply mounted into slide holders no sample preparation! 4 Filters can be Teflon, polycarbonate, Mylar etc. but not glass or quartz fibre

5 Capabilities 5 Capable of collecting and analysing PM samples on an hourly timescale (or any timescale of interest) Unique, specialized IBA capability Use in-house modified Streaker samplers Size resolved (PM and PM 2.5 )

6 Source Apportionment 6 Source determination is performed using factor analysis: Each factor represents a source Sources identified must make physical sense Q(E) = n m i = 1 j = 1 (e ik / kj ) 2 The primary technique used is positive matrix factorization (PMF): Accounts for data uncertainties and limits of detection Non-negativity constraints in solution

7 An example from Ulaanbaatar, Mongolia 7 PM 2.5 source profiles PM 2.5 source time-series Also perform back-trajectory analyses for identifying probable source locations

8 Hourly Sampling and Source Apportionment 8 ~60 hours (samples) collected per size-resolved filter Gravimetric PM mass not possible, a continuous E-BAM (MetOne) co-located Meteorological variables from an ultrasonic Vaisala Not possible / too onerous to analyse Streaker filters using XRF and NAA Can analyse ~250 samples per day AP sampler station

9 Application 9 Hourly PM 10 concentrations during winter in New Zealand urban areas display similar diurnal profiles, regardless of population What source(s) contribute to peak PM 10 concentrations? In particular, the morning peak at ~9am which is largest in small towns How is PM transported within the airshed?

10 10

11 Results from Nelson, New Zealand 11 Wood combustion identified as most significant contributor to evening and morning peak residents relighting or restoking fires in the morning Shipping emissions identified for the first time S and V in the source profile Vehicle contributions increase during peak hours

12 Who we work with in Asia Lead $1.2 million IAEA program, but have also worked with individual countries 12

13 Summary 13 What we offer Inexpensive multielemental analysis from hydrogen to uranium (20 elements plus in a single analysis run), source identification (man-made and natural) and apportionment techniques for Asian countries on PM Complete sampling stations for rent, including hourly-weekly PM (Streaker) samplers that can run in remote places in Asia. Competitive OC/EC and PAH measurements What the results can be Hourly studies of PM composition and sources improve understanding about population exposures throughout a day. Hourly source information coupled with meteorological information provide useful datasets for air quality modelling, monitoring and development of air pollution mitigation strategies.

14 Acknowledgments 14 Our customers in New Zealand and Overseas for continued support for more than 10 years. for technical and financial support. New Zealand government funding agencies for funding support. IAEA in Vienna for Programme Leadership in Asia. Our colleagues around the world for working with us on air pollution research for many years strong joint publication track record.