atmospheric pahs determination: influence of the air

ATMOSPHERIC PAHs DETERMINATION: ATMOSPHERIC PAHs DETERMINATION:

INFLUENCE OF THE AIR SAMPLING TIME INFLUENCE OF THE AIR SAMPLING TIME

PROGRAM IN THE OCCURRENCE OF PROGRAM IN THE OCCURRENCE OF

ARTIFACTSARTIFACTS

A&WMA International Specialty Conference: A&WMA International Specialty Conference:

Leapfrogging Opportunities for Air Quality ImprovementLeapfrogging Opportunities for Air Quality Improvement

CHINA, May 2010CHINA, May 2010

FRANCISCO CERECEDAFRANCISCO CERECEDA--BALICBALIC, V, Vííctor Vidal, ctor Vidal,

Juan Luis Guevara and NicolJuan Luis Guevara and Nicoláás Schiappacasse,s Schiappacasse,

LABORAT

ORIO DE QUIMIC

A AMBIENTA

L

Laboratorio de QuLaboratorio de Quíímica Ambiental mica Ambiental -- UTFSMUTFSM Dr. Francisco CerecedaDr. Francisco Cereceda

INTRODUCTIONINTRODUCTION

PAHsPAHs ((PPolycyclic olycyclic AAromatic romatic HHydrocarbons )ydrocarbons )

Naftaleno

PirenoBenzo (c) fenantreno

Coroneno

S

Benzonaftotiofeno Benzo(a)pireno

One of the greatest challenges in air pollution research, especiOne of the greatest challenges in air pollution research, especially which is ally which is

focuses on the study of PAHs, is the development of systems and focuses on the study of PAHs, is the development of systems and sampling sampling

procedures to obtain more accurate, reliable and representative procedures to obtain more accurate, reliable and representative information about information about

concentrations of these compounds and their variation in timeconcentrations of these compounds and their variation in time

SAMPLING ARTIFACTSSAMPLING ARTIFACTS

PAHPAHPAHPAHPAHPAHPAHPAH’’’’’’’’s +s +s +s +s +s +s +s +

•• NONONONONONONONOXXXXXXXX

•• OOOOOOOO33333333

•• ACID GASES AND OACID GASES AND OACID GASES AND OACID GASES AND OACID GASES AND OACID GASES AND OACID GASES AND OACID GASES AND O33333333

NITRONITRONITRONITRONITRONITRONITRONITRO--------PAHPAHPAHPAHPAHPAHPAHPAH’’’’’’’’ssssssss

OXYOXYOXYOXYOXYOXYOXYOXY--------PAHPAHPAHPAHPAHPAHPAHPAH’’’’’’’’ssssssss

HIGHLY POLAR HIGHLY POLAR HIGHLY POLAR HIGHLY POLAR HIGHLY POLAR HIGHLY POLAR HIGHLY POLAR HIGHLY POLAR

COMPOUNDSCOMPOUNDSCOMPOUNDSCOMPOUNDSCOMPOUNDSCOMPOUNDSCOMPOUNDSCOMPOUNDS

Atmospheric Environment, 33, 4977-4986 (1999)Chemosphere, 62, 1889-1898 (2006)

J. Atmospheric Environment, 29(19), 2575-2584 (1995)

•• REACTIONS OF PAHREACTIONS OF PAHREACTIONS OF PAHREACTIONS OF PAHREACTIONS OF PAHREACTIONS OF PAHREACTIONS OF PAHREACTIONS OF PAH’’’’’’’’s WITH COMPOUNDS PRESENT IN s WITH COMPOUNDS PRESENT IN s WITH COMPOUNDS PRESENT IN s WITH COMPOUNDS PRESENT IN s WITH COMPOUNDS PRESENT IN s WITH COMPOUNDS PRESENT IN s WITH COMPOUNDS PRESENT IN s WITH COMPOUNDS PRESENT IN

THE AIRTHE AIRTHE AIRTHE AIRTHE AIRTHE AIRTHE AIRTHE AIR

PROBLEMS IN PROBLEMS IN SAMPLING PROCEDURES SAMPLING PROCEDURES

•• EXCHANGE OF PAHs BETWEEN GASEOUS AND EXCHANGE OF PAHs BETWEEN GASEOUS AND EXCHANGE OF PAHs BETWEEN GASEOUS AND EXCHANGE OF PAHs BETWEEN GASEOUS AND EXCHANGE OF PAHs BETWEEN GASEOUS AND EXCHANGE OF PAHs BETWEEN GASEOUS AND EXCHANGE OF PAHs BETWEEN GASEOUS AND EXCHANGE OF PAHs BETWEEN GASEOUS AND

PARTICULATE PHASESPARTICULATE PHASESPARTICULATE PHASESPARTICULATE PHASESPARTICULATE PHASESPARTICULATE PHASESPARTICULATE PHASESPARTICULATE PHASES

Atmospheric Environment, 33, 4977-4986 (1999)Chemosphere, 49(3), 331-340 (2002)

PAH’s

GASEOUS

PHASE

ADSORBED PAH’s

-

+

FILTER

SURFACE

PMPMPMPM

• Artifact negative: some of the particulate organic compounds

is volatilized

• Artifact positive: a portion of the

organic vapor phase is adsorbed onto the filter surface

or onto the deposited particulate matter

THE OBJECTIVE OF THIS WORK WAS: TO THE OBJECTIVE OF THIS WORK WAS: TO

DETERMINATE A SAMPLING TIME PROGRAM DETERMINATE A SAMPLING TIME PROGRAM

THAT SATISFIES THE FOLLOWING CONDITIONS:THAT SATISFIES THE FOLLOWING CONDITIONS:

GOALGOAL

�� Collect enough PAHs amount to be Collect enough PAHs amount to be

measurable by GCmeasurable by GC--FID and GCFID and GC--MSMS

�� Minimize the occurrence of sampling Minimize the occurrence of sampling

artifacts, and generate a representative artifacts, and generate a representative

sample for a 24 hour periodsample for a 24 hour period

SSampling site: Santiago de Chile, ampling site: Santiago de Chile,

Metropolitan RegionMetropolitan Region


Sampling MethodologySampling Methodology

Parque O'Higgins monitoring station is located in Parque O'Higgins monitoring station is located in

downtown Santiago. It is placed in a large park downtown Santiago. It is placed in a large park

about 2 km south of the city downtown and 1 km about 2 km south of the city downtown and 1 km

west of a major highway with traffic of about west of a major highway with traffic of about

60,000 vehicles per day60,000 vehicles per day

Sampling System OutlineSampling System Outline

Speciation Sampler Partisol 2300 (R&P)Speciation Sampler Partisol 2300 (R&P)


Inlet AirInlet AirOutlet AirOutlet Air

12

3

4

56

7

8

PAHs in PAHs in

Gaseous phaseGaseous phase

PUF PUF

PAHs absorbed/PAHs absorbed/

adsorbed onadsorbed on

particulate matterparticulate matter

FILTERFILTER

Sampling Times Program (STP)Sampling Times Program (STP)


Qualitative and quantitative determinationQualitative and quantitative determination

of PAHs (PM + gas phase)of PAHs (PM + gas phase)

SamplingSampling ExtractionExtraction Evaporation/ Evaporation/

concentrationconcentrationPurificationPurification

(clean(clean--up)up)

IdentificationIdentification

PM phasePM phase

Gaseous phaseGaseous phase

QuantificationQuantification

MultiMulti--step Environmental Analytical Process step Environmental Analytical Process

Real Samples ChromatogramsReal Samples Chromatograms

of PAHs, (Filter and PUF)of PAHs, (Filter and PUF)


PUFPUF(escale 20 a 200 mV)(escale 20 a 200 mV)

FilterFilter(escale 20 a 200 mV)(escale 20 a 200 mV)

udl: under detection limitudl: under detection limit

ResultsResults

Total PAH concentration obtained at Total PAH concentration obtained at

different Sampling Times Programdifferent Sampling Times Program


EQUIVALENT EQUIVALENT

SAMPLING SAMPLING

PROGRAMSPROGRAMS

SAMPLING SAMPLING

PROGRAMS WITH PROGRAMS WITH

MORE ARTIFACTSMORE ARTIFACTS

Regression analysisRegression analysis

RegressionRegression

analysisanalysis

Hypothetical Hypothetical

equivalence equivalence

case a = 1case a = 1

1.25381.2538

0.31290.3129= 4.04.0

•• Were made a concentration analysis of atmospherics Were made a concentration analysis of atmospherics

samples of HAPs, obtained in a urban sampling station and samples of HAPs, obtained in a urban sampling station and

performed with three different STPperformed with three different STP

•• A significant sampling artifact was found when sampler A significant sampling artifact was found when sampler

works continuously for 24 hoursworks continuously for 24 hours

•• Statistical analysis showed that concentrations of PAHs Statistical analysis showed that concentrations of PAHs

obtained with longer time sampling ( 24 chr) are 4 times obtained with longer time sampling ( 24 chr) are 4 times

lower than those found at 1hr/6hr or 10min/1hrlower than those found at 1hr/6hr or 10min/1hr

•• 1hr/6hr or 10min/1hr are equivalents; nevertheless to get a 1hr/6hr or 10min/1hr are equivalents; nevertheless to get a

wider picture of the variation of pollutants through the day wider picture of the variation of pollutants through the day

(eg PAHs) it is proposed that the program of 10min/1hr is (eg PAHs) it is proposed that the program of 10min/1hr is

the most appropriatethe most appropriate


ConclusionsConclusions

ACKNOWLEDGEMENTSACKNOWLEDGEMENTSCollaborators in this work Collaborators in this work •• Environmental Chemistry LaboratoryEnvironmental Chemistry Laboratory

Environmental Technology CentreEnvironmental Technology Centre

UTFSMUTFSM

•• School of Environmental Engineering, School of Environmental Engineering,

Catholic University of TemucoCatholic University of Temuco

FONDECYT project 1070500FONDECYT project 1070500

FONDEF project D02FONDEF project D02--II--10054 10054

Proyecto Interno DGIP UTFSM NProyecto Interno DGIP UTFSM Nºº 130625130625

Secretaria Regional Miniterial de Salud del la RegiSecretaria Regional Miniterial de Salud del la Regióón n MetropolitanaMetropolitana”” (SEREMI de Salud RM) of the Health (SEREMI de Salud RM) of the Health MinistryMinistry

VVííctor Vidalctor Vidal

Juan Luis GuevaraJuan Luis Guevara

NicolNicoláás Schiappacasse s Schiappacasse

PUF Cleaning comparison between AutoExtractPUF Cleaning comparison between AutoExtract--PUFPUF®®

and Soxhlet extraction (EPAand Soxhlet extraction (EPA--TO13A) with GCTO13A) with GC--FIDFID

AutoExtractAutoExtract--PUF BlankPUF Blank(escale 0 a 150 mV)(escale 0 a 150 mV)

Soxhlet Blank Soxhlet Blank (escale 0 a 150 mV)(escale 0 a 150 mV)


PUFPUF

Before cleaningBefore cleaning(escale (escale --15 a 700 mV)15 a 700 mV)

PUFPUF

After cleaningAfter cleaning(escale (escale --15 a 700 mV)15 a 700 mV)


Comparison between before and after PUF cleaningComparison between before and after PUF cleaning

procedure wit AutoExtractprocedure wit AutoExtract--PUFPUF®® (GC(GC--FID)FID)

Chromatogram of 1 Chromatogram of 1 µµll standard standard

of 16of 16--EPA HAPs (8 EPA HAPs (8 ng/ng/µµl)l)


Samples processing of PAHsSamples processing of PAHs

in gas phase and particulate matterin gas phase and particulate matter (MP(MP2,52,5))


Similar samples treatment Similar samples treatment

is made,is made,

but separately but separately

PUF extraction in a automatic PUF extraction in a automatic

pneumatic extraction systempneumatic extraction system

AutoExtract PUFAutoExtract PUF®®

PUFPUF

Polyurethane Polyurethane

foam filterfoam filter

PAHs ab/adsorbed on PAHs ab/adsorbed on

particulate matter particulate matter PAHsPAHs

in gas phasein gas phase

FILTERFILTER

teflon membraneteflon membrane

0,45 0,45 µµµµµµµµm m ∅∅∅∅∅∅∅∅ porepore

Filter extraction with Toluene Filter extraction with Toluene

during 1h using reflux systemduring 1h using reflux system

Extract filtration on specially Extract filtration on specially

designed vacuum systemdesigned vacuum system

®® Patent pendentPatent pendent


Extract Concentration with rotary Extract Concentration with rotary

evaporatorevaporator

Evaporation under controlled Evaporation under controlled

nitrogen streamnitrogen stream

FILTERFILTER PUFPUF

Redisolution withRedisolution with

50 ul of Toluene50 ul of Toluene

Sample Clean Up on Sample Clean Up on

Silica Gel ColumnSilica Gel Column

chromatographicchromatographic

Identification Identification -- QuantificationQuantification

PAHs FractionPAHs Fraction

GCGC--FIDFIDGCGC--MSMS

Samples processing of PAHsSamples processing of PAHs

in gas phase and particulate matterin gas phase and particulate matter (MP(MP2,52,5))

Regression analysis: comparison Regression analysis: comparison

results of PAHs concentrations results of PAHs concentrations

obtained with different STPobtained with different STP

atmospheric pahs determination: influence of the air

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