C.N.R. Institute of Atmospheric Pollution EMEP TFMM 7th MEETING – HELSINKI, 10th-12th May 2006 PM10 and PM2.5 MASS CLOSURE in the LAZIO region (CENTRAL ITALY) Cinzia PERRINO C.N.R. Institute of Atmospheric Pollution Montelibretti (Rome) A study funded by the Lazio region

ROME – TRAFFIC STATION : OUR STARTING POINT ROME – TRAFFIC STATION : 194 PM10 EXCEEDANCES IN 2004 C. Perrino C.N.R. Istituto sull’Inquinamento Atmosferico – Montelibretti (Roma)

WHICH ARE THE DRIVING FACTORS DETERMINING THE TIME PATTERN OF ATMOSPHERIC POLLUTANTS? WHICH CONDITIONS LEAD TO EXCEEDANCES? WHICH COMPOUNDS ARE RESPONSABLE FOR THE INCREASE IN PM CONCENTRATION? WHICH SOURCES ARE RESPONSABLE FOR THE DIRECT OR INDIRECT PRODUCTION OF THESE COMPOUNDS? C. Perrino C.N.R. Istituto sull’Inquinamento Atmosferico – Montelibretti (Roma)

A research project funded by the Lazio Region “Fine Dust” 2004 - 2005 A research project funded by the Lazio Region FONTECHIARI regional background station LATINA urban station ROMA MONTEZEMOLO traffic station MONTELIBRETTI semi-rural station ROMA VILLA ADA urban background station VITERBO C. Perrino C.N.R. Istituto sull’Inquinamento Atmosferico – Montelibretti (Roma)

C. PERRINO - C.N.R. Institute of Atmospheric Pollution Study of the chemical composition of atmospheric particles apportionment of particle sources discrimination between natural and anthropogenic events October 2004 – July 2005 (daily sampling – analysis of the 140 most interesting days) Six stations: 1 regional background, 1 urban background, 1 peri-urban, three urban stations (Roma, Latina Viterbo) Two size fractions: PM10, PM2.5 C. PERRINO - C.N.R. Institute of Atmospheric Pollution

3-step procedure: Natural radioactivity monitoring Mixing properties of the lower atmosphere Size distribution of particulate matter Chemical composition of particles Natural radioactivity monitoring Optical particle counter Analysis of metals, ions, carbon compounds C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

about the air volume available for pollution dispersion atmospheric concentration of pollutants emission (and physico-chemical trasnformation) mixing properties of the lower atmosphere Having information about the air volume available for pollution dispersion we could uncouple pollutants variations due to changes in the emission rate from those due to changes in the dilution properties of the atmosphere C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

SHORT-LIVED RADON PROGENY STEP 1: Mixing properties of the lower atmosphere 238URANIUM DECAY CHAIN 222RADON SHORT-LIVED RADON PROGENY C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

STEP 1: Mixing properties of the lower atmosphere Convective mixing of the lower atmosphere: Radon dilutes into the whole mixing layer Weak mixing of the lower atmosphere: Radon is trapped in the lower layer and its air concentration increases

STEP 1: Mixing properties of the lower atmosphere ATMOSFERIC STABILITY MONITOR the instrument collects atmospheric particles and determines the natural radioactivity due to Radon progeny (1-h average). good index of the dilution properties of the lower atmosphere identification of stability periods and advection periods

During warm months natural radioactivity shows a well-defined and modulated temporal pattern (all days are similar: nocturnal stability and convective mixing during the day) During cold months high-pressure periods are sporadic and advection often occurs. Diurnal mixing is weak and of limited duration. C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

ROME - Traffic station NATURAL RADIOACTIVITY NATURAL RADIOACTIVITY JUNE – JULY 2003 DECEMBER 2003 NATURAL RADIOACTIVITY JUNE – JULY 2003 NATURAL RADIOACTIVITY DECEMBER 2003 C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

STEP 1: Mixing properties of the lower atmosphere C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

STEP 1: Mixing properties of the lower atmosphere C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

STEP 1: Mixing properties of the lower atmosphere Starting from natural raadioactivity values we can develop Atmospheric Stability Indexes… EXPERIMENTAL FORECASTED … for each day, they give the probability, from the meteorological point of view, for the occurrence of an atmospheric pollution event C. Perrino C.N.R. Istituto sull’Inquinamento Atmosferico – Montelibretti (Roma)

The episode of December 27th 2003 in Rome: traffic or meteorology? C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

The mixing properties of the lower atmosphere are a key factor FIRST REMARK The mixing properties of the lower atmosphere are a key factor in determining PM concentration level and its time variations C. Perrino C.N.R. Istituto sull’Inquinamento Atmosferico – Montelibretti (Roma)

3-step procedure: Natural radioactivity monitoring Mixing properties of the lower atmosphere Size distribution of particulate matter Chemical composition of particles Natural radioactivity monitoring Optical particle counter Analysis of metals, ions, carbon compounds C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

STEP 2: Size distribution of particulate matter Optical particle counter in six size ranges: 0.3 – 0.5 m; 0,5 – 1,0 m; 1,0 – 1,5 m; 1,5 – 2,0 m 2 – 5 m; 5 – 10 m C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

STEP 2: Size distribution of particulate matter Evaluation of the ratio between the number of particles in the coarse ( > 1,5 m) and the fine (0,3 – 0,5 m) ranges C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

IDENTIFICATION OF NATURAL EVENTS STEP 2: Size distribution of particulate matter Daily average ratio between the number of particles in the coarse ( > 1,5 m) and the fine (0,3 – 0,5 m) ranges IDENTIFICATION OF NATURAL EVENTS C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

FASE 2: DISTRIBUZIONE DIMENSIONALE DELLE PARTICELLE In the case of natural events (e.g. Saharan dust intrusions) the Atmospheric Stability Indexes are much lower than the real concentration of PM C. Perrino C.N.R. Istituto sull’Inquinamento Atmosferico – Montelibretti (Roma)

3-step procedure: Natural radioactivity monitoring Mixing properties of the lower atmosphere Size distribution of particulate matter Chemical composition of particles Natural radioactivity monitoring Optical particle counter Analysis of metals, ions, carbon compounds C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

STEP 3: Chemical composition of particles Ion chromatography (IC) Chemical characterisation: 1.  Anions and cations (NO3-, SO4=, Cl-, Na+, Ca++, Mg++, K+, NH4+)  2. Elemental carbon and organic carbon compounds (EC, OC) 3.  Crustal metals (major components) (Si, Al, Fe, Ca, K) 4. Inorganic volatile components (ammnium chloride and nitrate) Termo-optical analyser X-ray fluorescence (ED-XRF) Sampling by diffusion lines and IC analysis C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

PM10 PM2.5 plus DIFFUSION LINES at ML station STEP 3: Chemical composition of particles PM10 PM2.5 Teflon filter Quartz filter Crustal metals ED-XRF Termo-optical analyser Organic carbon Elemental carbon Extraction plus DIFFUSION LINES at ML station Trace metals ICP Ion chromatography Univ.of Rome “La Sapienza” Chemistry Department Anions and cations C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

MASS CONCENTRATION OF PM10 IN MONTELIBRETTI (ROME) MEASURED BY THE DUST MONITOR (blue) AND RECONSTRUCTED BY THE CHEMICAL ANALYSES (red) C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

MASS CONCENTRATION OF PM2.5 IN MONTELIBRETTI (ROME) MEASURED BY THE DUST MONITOR (blue) AND RECONSTRUCTED BY THE CHEMICAL ANALYSES (red) C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

STEP 3: Chemical composition of particles 10-15% of the ammonium nitrate is lost by the 20°C monitor and about 80% is lost by the 45°C monitor C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

[secondary compounds] = NH4+ + SO4= + NO3- + (OM – EC) STEP 3: Chemical composition of particles 4 main sources [sea-spray aerosol] = (Na+ + Cl-) * 1.176 [SO4= Mg Ca K] [crustal] = (1.89 Al + 2.14 Si + 1.4 Ca + 1.2 K + 1.36 Fe) * 1.12 [Mg Na Ti] [primary anthropogenic compounds] = EC * 2 [OM] [secondary compounds] = NH4+ + SO4= + NO3- + (OM – EC) OM = a OC a = 1.6 ÷ 2.1 C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

STEP 3: Chemical composition of particles C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

STEP 3: Chemical composition of particles C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

STEP 3: Chemical composition of particles Sea-spray events: NaCl concentration increases from 1-2% to 20-40% the coarse/fine ratio increases they occur in advection conditions (generally clean air masses) PM10 concentretion is low; the increase due to sea-salt is generally < 10 ug/m3 generally they do no cause exceedances they have low impact on PM2.5 concentration C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

STEP 3: Chemical composition of particles C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

STEP 3: Chemical composition of particles Saharan dust events: crustal matter concentration increases from 10-20% to over 50% the coarse/fine ratio increases they begin in advection conditions (but re-suspension may increase the time duration of the episode) PM10 concentretion can be very high (up to more than 100 ug/m3) they often cause exceedances they also generally cause an increase of PM2.5 concentration C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

STEP 3: Chemical composition of particles 38.0 mg/m3 146.4 mg/m3 58.8 mg/m3 IDENTIFICATION AND CHARACTERISATION OF NATURAL EVENTS: SEA-SPRAY AFRICAN DUST

Natural events can be identified SECOND REMARK Natural events can be identified from an increase of the coarse-to-fine ratio and are characterised by advection conditions C. Perrino C.N.R. Istituto sull’Inquinamento Atmosferico – Montelibretti (Roma)

STEP 3: Chemical composition of particles ELEMENTAL CARBON PRIMARY ANTHROPOGENIC POLLUTANTS C. Perrino C.N.R. Istituto sull’Inquinamento Atmosferico – Montelibretti (Roma)

STEP 3: Chemical composition of particles Average % composition of PM10 in the Lazio region C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

STEP 3: Chemical composition of particles Average % composition of PM2.5 in the Lazio region C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

For primary anthropogenic pollutants we cannot identify “events” THIRD REMARK For primary anthropogenic pollutants we cannot identify “events” Their concentration depends on the proximity to the emission sources and their concentration variations mainly depend on the dispersion capacity of the lower atmosphere C. Perrino C.N.R. Istituto sull’Inquinamento Atmosferico – Montelibretti (Roma)

STEP 3: Chemical composition of particles SULPHATE SECONDARY POLLUTANTS C. Perrino C.N.R. Istituto sull’Inquinamento Atmosferico – Montelibretti (Roma)

STEP 3: Chemical composition of particles Average % composition of PM10 in the Lazio region C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

STEP 3: Chemical composition of particles Average % composition of PM2.5 in the Lazio region C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

PM10 STEP 3: Chemical composition of particles Secondary pollutants are homogeneously distributed at least on a regional scale. C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

STEP 3: Chemical composition of particles PM10 PM2.5 PM10-2.5 C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

For secondary pollutants we cannot identify “events” FOURTH REMARK For secondary pollutants we cannot identify “events” Their concentration is homogeneous on a regional scale and their concentration variations mainly depend on the dispersion capacity of the lower atmosphere C. Perrino C.N.R. Istituto sull’Inquinamento Atmosferico – Montelibretti (Roma)

PM composition during polluted days STEP 3: Chemical composition of particles PM10 concentration lower than 35 mg/m3 PM10 concentration higher than 65 mg/m3 PM composition during polluted days is very close to PM composition during clean days with the exception of days characterised by important natural events C.N.R. Institute of Atmospheric Pollution – Rome (ITALY)

THANK YOU FOR YOUR ATTENTION ! C. Perrino C.N.R. Istituto sull’Inquinamento Atmosferico – Montelibretti (Roma)

STEP 3: Chemical composition of particles

PM10 - 2.5 FASE 3: COMPOSIZIONE CHIMICA DEL MATERIALE PARTICELLARE SIA L’AEROSOL MARINO CHE LE SPECIE DI DERIVAZIONE TERRIGENA SONO UNA COMPONENTE QUANTITATIVAMENTE IMPORTANTE DELLA FRAZIONE COARSE C. Perrino C.N.R. Istituto sull’Inquinamento Atmosferico – Montelibretti (Roma)