mountains, witnesses of global changes research in the himalaya and karakoram: share-asia project...

MOUNTAINS, WITNESSES OF GLOBAL CHANGES

Research in the Himalaya and Karakoram:

SHARE-Asia Project

Rome, November 2005

Ev-K2-CNR

RATEAP project

ResponsibleResponsible

Dr. Mario GalloriniDr. Mario Gallorini

Remote Areas

Trace Elements

Atmospheric Pollution

CNR - Institute of Metrology “G.Colonnetti”

Unit of Radiochemistry and Spectroscopy c/o University of Pavia - Italy

ELEMENTAL CHARACTERIZATION OF HIMALAYAN AIRBORNE PARTICULATE MATTER COLLECTED AT 5,100 M OF ALTITUDE.

E.Rizzio1, G.Giaveri1, L.Bergamaschi1, A.Profumo1, G.Tartari2, M.Gallorini1

1 CNR Institute of Metrology “G.Colonnetti” Unit of Radiochemistry and Spectroscopy c/o University of Pavia (Italy) 2CNR- IRSA, Brugherio-Milano (Italy)

Corresponding author: gallorin@unipv.it

Goals of the project:

• Obtaining information about the concentrations of trace elements (TE) in the air particulate in the Himalayas, contributing to study the Asian Brown Cloud

• Checking for possible air pollution and identification of those TE that may be considered of non local and/or of anthropic origin;

• Evaluation of possible origin and direction of long distance transport phenomena and their variation with seasonal/meteorological conditions;

The project is carried out thanks to:

• The use of the “Pyramid” laboratory of the CNR at 5050m a.s.l. in the Himalayas (Nepal) in the surroundings of mount Everest

• The financial support of the Ev-K2- CNR Committee • The logistic support of “Mountain Equipe” s.r.l.– Bergamo, Italy

• The sampling equipment specifically developed and supplied by Zambelli s.r.l. (Bareggio, Milan)

• The use of the research nuclear reactor TRIGA Mark II

of the University of Pavia, Italy

• The expertise matured by the working group of Pavia in the field of trace element air pollution, including previous studies on lichens, collected in the same region, and used as biomonitors

- aspiration pumps (for low pressure conditions)

- filters (Teflon®, 0.5 µm porosity, by Pall), blank study

- training for working in extreme conditions

Plateau Rosa, Italian Alps - 3500m

2001 - Preparation

Samplings

2002: Pre-monsoon ( March – May )

2003: Post-monsoon (October)

- Samples of 3 airborne particulate fractions: TSP, PM10, PM2.5

120m3 of aspired air (sampling time 80 –120h) for each sample - field blanks, soil samples, lichen samples

Sampling site near the pyramid Use of the pyramid’s laboratory

Weather conditions acquired from the Epson Meteo station settled at the Pyramid

Temperature (daily mean range) Precipitation (daily median)Mean Relative HumidityAtmospheric PressureWind speed and direction

Analyses

Carried out by INAA and ETAAS -       Blank study-       Quality control

filters of TSP filters of PM10 filters of PM2.5

INAA (26 elements) ETAAS (5 elements)

-       Soil samples to calculate Enrichment Factors (EF)-       Lichens (air pollution biomonitors)

Element blank filter field-blank filter

field-blank contribution in PM 2.5 analysis

ng/filter ng/filter %

As 0.5 ±0.2 0.5 ±0.3 18 Br 14 ±5 27 ±18 34 Ca 2260 ±900 2625 ±1400 60 Ce <0.8 <0.8 11 max. Cl 890 ±350 1100 ±240 74 Co 4.3 ± 2 4.5 ±3 34 Cr 136 ± 47 153 ± 60 >100 Cs 0.2 ± 0.05 0.2 ±0.05 19 Fe 1970 ± 5 92 2120 ± 510 50 Hf 0.18 ±0.07 0.18 ±0.07 34 Hg <0.5 <0.5 n.d. I <10 <10 38 max. K 1000 ±300 1000 ±300 22 La 1.5 ±0.5 1.7 ±0.5 25 Mg 1240 ±230 1300 ±265 44 Ni 130 ± 47 153 ± 51 > 100 Mn 43 ±8 40 ±9 54 Mo 11 ± 8 12 ± 9 >100 Rb <0.6 <0.5 3.7 max. Sb 2.8 ±0.8 2.8 ±1.0 19 Se <0.8 <0.8 40 max. Sc 0.21 ±0.07 0.17 ±0.10 11 Ta <0.1 <0.1 n.d. Ti 200 ± 70 180 ± 95 36 Th 0.14 ±0.09 0.17 ±0.11 12 U <0.3 <0.3 n.d. V 2.1 ±1.4 2.7 ±1.8 16 Zn 109 ± 39 131 ± 43 34

Elemental content (nanograms) in blank filters and field-blank filters (0.5 um 47 mm diameter ZefluorTM , PALL-USA) determined by INAA

Trace elements content in the different particles size fractions of air particulate matter collected at 5100 m a.s.l. (Khumbu valley-CNR Pyramid, March-May 2002). Concentration in ng/Nm3

Himalayas Himalayas Ispra MilanIspra Milan

Br 1.0 – 3.1 Br 1.0 – 3.1 8 - 148 - 14 280 – 758280 – 758

Cd 0.02 – 0.05 0.35 – 0.34 1.7 – 6.3Cd 0.02 – 0.05 0.35 – 0.34 1.7 – 6.3

Ni 0.8 – 2.0 6.7 – 15 3.9 – 167Ni 0.8 – 2.0 6.7 – 15 3.9 – 167

Pb 2.4 – 6.8 61 – 154 75 - 3200Pb 2.4 – 6.8 61 – 154 75 - 3200

Sb 0.08 – 0.65 4.0 – 6.1 55 –125Sb 0.08 – 0.65 4.0 – 6.1 55 –125

Trace elements content in the different particles size fractions of air particulate matter collected at 5100 m a.s.l. (Khumbu valley-CNR Pyramid, October 2003). Concentration in ng/Nm3

Post – monsoon period

Variation (%) of the elemental concentrations in the Hymalaian airborne particulate fractions between the pre-monsoon (March-May 2002) and the post-monsoon (October 2003) periods.

TSP TSP PM 10 PM 2.5PM 10 PM 2.5

Cr -89 % -89 % -92 %Cr -89 % -89 % -92 %

Co -70 % -82 % -89 %Co -70 % -82 % -89 %

Br +18 % -14 % -2.5%Br +18 % -14 % -2.5%

I +84 % +137 % +125 %I +84 % +137 % +125 %

0

35

70

105

140

Seasonal frequency of days with precipitations in 2000 - 2004

Days

TSP (As conc.)

Precip. (mm rain)

Mean 0.14 ± 0.04 (28 %)

Elemental characterization of Himalayan airborne particulate at CNR Pyramid (5050 msl) pre-monsoon period: March – May 2002 and post-monsoon (October 2003)

As ng/Nm3

Mean 0.064 0,02 (31%)

Variation: - 54%

pre-monsoon post-monsoon

TSP (Co conc.)

Precip. (mm rain)

Mean 0.43 ± 0.12 (28 %)

Elemental characterization of Himalayan airborne particulate at CNR Pyramid (5050 msl) pre-monsoon period: March – May 2002 and post-monsoon (October 2003)

Co ng/Nm3

Variation: - 70%

pre-monsoon post-monsoon

Mean 0.10 0.04 (40%)

TSP (Zn conc.)

Precip. (mm rain)

Mean 11.2 ± 5.4 (49 %)

Elemental characterization of Himalayan airborne particulate at CNR Pyramid (5050 msl) pre-monsoon period: March – May 2002 and post-monsoon (October 2003)

Zn ng/Nm3

Mean 4.14 1.70 (41 %)

Variation: - 63%

pre-monsoon post-monsoon

TSP (I conc.)

Precip. (mm rain)

Mean 1.1 ± 0.4 (36 %)

Elemental characterization of Himalayan airborne particulate at CNR Pyramid (5050 msl) pre-monsoon period: March – May 2002 and post-monsoon (October 2003)

I ng/Nm3

Mean 2.0 0.6 (30%)

Variation: + 85%

pre-monsoon

post-monsoon

Variation (%) of the elemental repartition in the PM10 and PM2.5 fractions of the Hymalaian airborne particulate between the pre-monsoon and the post-monsoon periods

0

300

600

TSP PM 10 PM 2.5

Pre - monsoon concentrations

Post - monsoon concentrations

Variation of the elemental repartitions of PM 10 and 2.5 fractions, between pre-monsoon (March/April 2002) and post-monsoon (October 2003) periods.

Ca

TSP/ PM 2.5 Pre-M = 7.4

TSP/ PM 2.5 Post-M= 2.4

0

6

12

TSP PM 10 PM 2.5

Pre - monsoon concentrations

Post - monsoon concentrations

Variation of the elemental repartitions of PM 10 and 2.5 fractions, between pre-monsoon (March/April 2002) and post-monsoon (October 2003) periods.

Mn

TSP/ PM 2.5 Pre-M = 10.4

TSP/ PM 2.5 Post-M = 7.7

0

0,1

0,2

TSP PM 10 PM 2.5

Pre - monsoon concentrations

Post - monsoon concentrations

Variation of the elemental repartitions of PM 10 and 2.5 fractions, between pre-monsoon (March/April 2002) and post-monsoon (October 2003) periods.

Se

TSP/ PM 2.5 Pre-M = 5.7

TSP/ PM 2.5 Post-M = 2.0

0

1,3

2,6

TSP PM 10 PM 2.5

Pre - monsoon concentrations

Post - monsoon concentrations

Variation of the elemental repartitions of PM 10 and 2.5 fractions, between pre-monsoon (March/April 2002) and post-monsoon (October 2003) periods.

I

TSP/ PM 2.5 Pre-M = 2.8

TSP/ PM 2.5 Post-M = 2.3

SUMMER - MONSON

Air mass Trajectory – Winter - Dry (2000 – 2004)

WINTER - DRY

Air mass Trajectory – Summer Monsoon (2000 – 2004)

Arabic Sea

Comparison between the trace elements EF calculated in airborne particulate matter and in lichens collected at high altitude in the Himalayas (Khumbu valley - CNR Pyramid, March-May 2002)

Airborne particulate

Lichens (collected at high altitude 4700-5100 m. s. l.)

Element TSP Hypogymnia Umbilicaria Alectoria

As 2.9 1.9 8 6.4

Br 43 151 55 166

Cd 59 32 37 42

Ce 0.4 2.1 1.5 0.2

Co 3.2 2.5 1.5 0.2

Cr 7 1.1 0.9 0.4

Cs 0.5 0.5 0.6 0.4

Cu 21 2.3 8.1 8.4

Fe 1.1 1 0.9 0.5

Hf 0.3 1 0.6 0.3

K 0.8 1.3 1.7 1.6

La 0.4 1.8 1.3 0.4

Mg 0.7 0.7 0.5 0.3

Mn 1.7 1.6 0.6 0.8

Ni 7 - - -

Pb 9 3.7 5.3 1.9

Rb 0.5 1 0.8 0.3

Sb 320 120 70 170

Se 4.3 1.3 0.1 0.6

Sc 1 1 1 1

Th 0.3 1.9 1.5 0.3

V 1.6 0.5 0.6 -

Zn 14 9.6 22 8.9

Cx APM / Cn APM

EF = --------------------- Cx Soil / Cn Soil

Where Cx is the concentration of the X element whose EF is to be determined

Cn is the concentration of the normalizing element assumed to be uniquely characteristic of the background

Data Quality Assurance

All the results have been checked and evaluated for the analitycal quality control by using the certified reference material

SRM 2783 “Trace Elements on Filter Media” NIST - USA

IAEA Laboratories Seibersdorf, Austria; M. Bogovac,IAEA Laboratories Seibersdorf, Austria; M. Bogovac,

A. Mendoza; A. MarkowiczA. Mendoza; A. Markowicz

ANSTO, Australia; I. OrlicANSTO, Australia; I. Orlic

Ghent University, Belgium; W. MaenhautGhent University, Belgium; W. Maenhaut

University of São Paulo, Brazil; P. ArtaxoUniversity of São Paulo, Brazil; P. Artaxo

Rudjer Boškoviç Institute, Croatia; M. JakašiçRudjer Boškoviç Institute, Croatia; M. Jakašiç

Nuclear Physics Institute, Czech Republic; J KuNuclear Physics Institute, Czech Republic; J Kuččeraera

University of Pavia, Italy, M. Gallorini; E. RizzioUniversity of Pavia, Italy, M. Gallorini; E. Rizzio

U.S. EPA, Research Triangle Park, NC, USA; J. U.S. EPA, Research Triangle Park, NC, USA; J. Weinstein Weinstein

Conclusions

• INAA has demonstrated its great capability in performing multielemental analyses at 10-9 g (nanogram) level on fractions of few milligrams of air dust collected onto filters

• The first and preliminary elemental characterization of the airborne particulate matter collected in the Himalayas region at 5100 m a.s.l. during the pre-monsoon and post-monsoon periods (2002/2003) has been accomplished

• As expected, all the concentration values found in this work are very low and can be taken as baseline values of unpolluted high altitude remote areas

• Nevertheless, the Enrichment Factors indicate that some elements found in the Himalayan air particulate are partially of a non–local origin. Their concentrations in the PM2.5 suggests the presence of long distance transport phenomena.

• A sensible seasonal variation between pre and post monsoon periods has been noticed for all the elements present in the airborne particulates being their concentrations, much lower in the post-monsoon period

• Iodine and, to some extent bromine, show in the post-monsoon period an enrichment of their concentrations that may be explained with the arrival of a southern air mass component coming from the Arabic Sea

• The quite good correspondence of EF values of many elements found in lichens and in the airborne particulate may suggest the use of lichens as trace metals permanent biomonitors also in this part of the world

Further research 

• Obtain information about the trace elements concentration and their distribution in the aerosols dispersed in the different layers of the Himalayan troposphere; 

• evaluation of the elements concentration variation with altitude (2650- 3570-5050 m a.s.l.) along a North-South transect during the pre and post monsoon seasons;  

• this can give important information about the elemental composition of the pollutant aerosols present in the northern margin of Asian Brown Cloud ;  

• the results will furnish fundamental data for assessing both air quality and possible trans-boundary air pollution phenomena in the Himalayan region.