This is a study of the existance of VOC compounds in the atmosphere of the city of Medellín in Colombia

1. ASSESMENT OF ORGANIC COMPOUNDS AS
VEHICULAR EMISSION TRACERS IN THE
ABURRA VALLEY REGION OF COLOMBIA
Miriam Gómez (1), Enrique Posada (2), Viviana Monsalve (2)
(1) Politécnico Colombiano Jaime Isaza Cadavid, Carrera 48 # 7-
151, Medellín, Colombia;
(2) INDISA S.A. Carrera 75 # 48 A 27, Medellín, Colombia
Presenting author email: enrique.posada@indisa.com
Talk 1078

2. Summary
The Aburrá Valley region in Colombia, with Medellín as its main
city, is an urban centre with about three million people.

3. Summary
An investigation was carried on to determine a set of baseline
concentrations for aliphatic hydrocarbon from n-nonane to n-
pentadecane, naphthalene, methylnaphtenes and phenanthrene
as vehicular emission tracers in the region.
The VOC measurement campaigns based on TENAX tube
sampling and analysis according to TO-17 EPA method were done
in areas of low and high vehicular flow as well as on-board
measurements covering major Medellín road networks during a
24 hour period.
The results show that there is a relation between VOCs
concentrations and vehicular activity.

4. Summary
At the time of the study, the sulfur content of the diesel fuel used
in the region, was changed from 2100 ppm to 50 ppm.
A study was carried also with a diesel motor, in a research
laboratory, working with fuel with sulfur contents of 50, 500 and
2100 ppm, to determine exhaust gas emission concentrations of
the same said organic compounds.
The results show that there is a relation between VOCs emissions
and sulfur content. This shows that the diesel fuel sulfur content
seems to be an important factor on VOC formation for the case of
diesel operated vehicles.

5. VOLATILE ORGANIC COMPOUNDS (VOC)
VOCs tend to be highly polluting both from their inhalation effects and
as a source of secondary pollutants.
For the present study they were classified into two (2) groups:
polynuclear aromatic hydrocarbons (PAHs) and aliphatic hydrocarbons
(AH).
Naphthalene
a polynuclear aromatic hydrocarbon
n-pentadecane
an aliphatic hydrocarbon (AH)

6. VOLATILE ORGANIC COMPOUNDS (VOC)
VOC an important role in today's environmental problems by their
accumulation and persistence in the environment.
Some VOCs, especially those of high molecular weight, resists
oxidation processes and become persistent, being adsorbed on
particles and transported over long distances), powering the global
greenhouse effect.
There is a need to control VOC
emissions to reduce ozone
formation. Ground-level ozone
impacts human health and damages
vegetation. Ozone is largely created
by a photochemical reaction
between nitrogen oxides (NOx) and
VOCs in the presence of sunlight.
NOx and VOCs are ozone precursors.

7. VOLATILE ORGANIC COMPOUNDS (VOCs)
So far no studies of these compounds have been done locally, so it was
deemed important to carry an exploratory work, in parallel with the
fact that S content of diesel fuel was undergoing changes at the time,
from 2000 to 50 ppm and it was desired to correlate those changes
with the said VOCs concentrations. The following VOCs were studied:
Compound studied Type Formula
n-Nonane AH C9H20
n-Decane AH C10H22
n-Undecane AH C11H24
n-Dodecane AH C12H26
n-Tridecane AH C13H28
n-Tetradecane AH C14H30
n-Pentadecane AH C15H32
Naphthalene PAH C10H8
1-Methylnaphthalene PAH C11H10
2-Methylnaphthalene PAH C11H10
Phenanthrene PAH C14H10
1-Methylphenanthrene PAH C15H12
2-Methylanthracene PAH C15H12

8. Compound
Molecular
weight
Vapor
pressure at
25 °C, mm Hg
Boiling
temperature
at
atmospheric
pressure, °C
n-Nonane 128,3 4,45 150,6
n-Decane 142,3 1,43 174,2
n-Undecane 156,3 0,412 196,0
n-Dodecane 170,4 0,135 214,0
n-Tridecane 184,4 0,0560 232,0
n-Tetradecane 198,4 0,0116 253,0
n-Pentadecane 212,4 0,00310 268,0
Naphthalene 128,2 0,0850 218,0
1-Methylnaphthalene 142,2 0,0670 240,0
2-Methylnaphthalene 142,2 0,0550 241,0
Phenanthrene 178,2 0,000121 332,0
1-Methylphenanthrene 192,3 0,0000501 354,0
2-Methylanthracene 192,3 0,0000727 353,5

9. 0,00
0,01
0,02
0,03
0,04
0,05
0,06
0,07
0,08
0,09
0,10
0,0
0,5
1,0
1,5
2,0
2,5
3,0
3,5
4,0
4,5
5,0
120 140 160 180 200 220
VaporpressurePAHat25°C,mmHg
Vaporpressurealkanesat25°C,mmHg
Molecular weight
Alkanes PAH
BEHAVIOR ACCORDING TO TWO TYPES
The studied VOC behave differently, following the two main types
(alkanes [AH], and PAH)

10. BEHAVIOR ACCORDING TO TWO TYPES
The studied VOC behave differently, following the two main types
(alkanes [AH], and PAH)
0
50
100
150
200
250
300
350
400
120 140 160 180 200 220
Boilingtmperatureatatmospheric
pressure,°C
Molecular weight
Alkanes PAH

11. Compound
Residence
half time
in air, hr Health Impact Occupational Limits
n-Nonane 40,8
Irritation eyes, skin, nose, throat;
headache, drowsiness, dizziness,
confusion, nausea, tremor,
discordination TLV: 200ppm (1050mg/m3)
n-Decane 33,2 Irritation eyes, skin. Little impact TLV Not established
n-Undecane 29 No clear indication of risks TLV Not established
n-Dodecane 27 Irritation eyes, skin. Little impact
TEEL-0: Concentration below
which people will experience
no adverse health effects =
0,015 ppm ( 105 μg/m3)
n-Tridecane 24
Irritating to eyes and skin. Inhalation
causes irritation of the lungs and
respiratory system. TLV Not established
n-Tetradecane 19,2
Irritation eyes, skin. Inhalation causes
irritation of the lungs and respiratory
system TLV Not established
n-Pentadecane 17 No clear indication of risks TLV Not established
Naphthalene 18 Irritating to skin and eyes TWA 10 ppm (50 mg/m3)
1-Methylnaphthalene 7,3
Irritation. Toxic by all routes (ie,
ingestion, inhalation, and skin contact) TLV = 0,5 ppm (2,9 mg/m3)
2-Methylnaphthalene 7,4 Irritating to skin TLV = 0,5 ppm (2,9 mg/m3)
Phenanthrene 36 - 1570
A known irritant, photosensitizing skin
to light. Potential occupational
carcinogen TWA = 0,028 ppm (0,2 mg/m3)

12. Compound Type
% in typical
diesel low S
fuel Gasoline
n nonane AH 0,84 0,24
n decane AH 0,92 0,19
n undecane AH 0,93 0,15
n dodecane AH 1,01 0,11
n tridecane AH 1,61 0,09
n tetradecane AH 1,21 0,03
n pentadecane AH 1,09 0,01
Total studied AH AH 7,61 0,82
naphthalene PAH 0,36 0,30
Typical contents of studied VOC in low sulfur diesel and
gasoline (ref. 7)
The other studied PAH come from oil and coal tars and incomplete
combustion, including wood combustion; Phenanthrene is also
associated with cigarrete and marihuane smoke and charcoal broil

13. Methodology (1)
A measurement campaign was conducted in three sites, two of
them with heavy traffic, the other one a rural park with low or
inexistent traffic, from July to August 2010, with sampling
periods of 24 hours.

14. Methodology (2)
Another sample was taken sampling during a 24 hour period
continuously, within a vehicle moving through designed zones
in the city, representative of medium to heavy traffic streets.
The sampling method applied was EPA TO-17 using 90 mm
length, 5 mm dia. stainless steel TENAX adsorption tubes filled
with appropriate sorbent materials.

15. Methodology (3)
Additional samples were taken in the discharge of a diesel motor
(four cylinders, 2.5 liter) working under standardized laboratory
conditions with diesel fuel of variable S content. Run cycles followed
standard ECE-M2 at 2420 rpm.

16. Sampling and Chemical Analysis Methodology
The sampling was done following method TO-17 EPA using a TENAX system,
with SS adsorption tubes, 90 mm long, 5 mm diameter, filled with
appropriate adsorbent material, prepared and supplied by the RDI (Desert
Research Institute at Reno, Nevada, USA). The chemical analysis of the
studied VOCs, was also done at the DRI, using the Agilent Thermal
Desorption-Gas Chromatograph/Mass Spectrometer (TD-GC/MS) system.
TENAX tubes (source DRI)
1 Flow direction at sampling 2- Flow direction at desorption 3 SS tube
4 Adsorbent material 5 Retaining SS mesh 6 glass wool

17. Sampling sites (1)

18. Sampling sites (2)
On board sampling pathway

19. Results (1)
Compound
Poblado,
05/08/10
Poblado,
07/08/10
Poblado,
10/08/10
Botanic
garden,
20/08/10
Arvi Park,
31/08/10
Type of zone urban urban urban urban rural
n-Nonane 0,870 0,736 0,769 1,896 0,060
n-Decane 0,980 0,696 0,693 2,273 0,046
n-Undecane 0,668 0,473 0,467 1,417 0,038
n-Dodecane 0,389 0,301 0,324 0,685 0,025
n-Tridecane 0,274 0,237 0,237 0,516 0,031
n-Tetradecane 0,244 0,218 0,225 0,583 0,027
n-Pentadecane 0,241 0,190 0,207 0,986 0,057
Naphthalene 0,989 0,839 0,836 2,269 0,139
1-Methylnaphthalene 0,212 0,179 0,200 0,741 0,010
2-Methylnaphthalene 0,428 0,357 0,407 1,520 0,016
Phenanthrene 0,038 0,023 0,022 0,141 0,005
1-Metylphenanthrene 0,000 0,000 0,000 0,158 0,000
2-Methylanthracene 0,000 0,000 0,000 0,182 0,000
Total studied VOC 5,334 4,248 4,388 13,369 0,456
Total studied AH 3,666 2,851 2,922 8,357 0,286
Total estudied PAH 1,667 1,398 1,466 5,012 0,170
Concentrations, μg/m3 in the urban and rural zones studied, 24 hr samples

20. Results (2)
Compound
On board run ,
05/08/10
Type of zone urban
n-Nonane 1,919
n-Decane 1,986
n-Undecane 1,728
n-Dodecane 0,564
n-Tridecane 0,730
n-Tetradecane 1,588
n-Pentadecane 6,379
Naphthalene 0,637
1-Methylnaphthalene 0,322
2-Methylnaphthalene 0,576
Phenanthrene 1,279
1-Metylphenanthrene 0,426
2-Methylanthracene 0,523
Total studied VOC 18,657
Total studied AH 14,894
Total estudied PAH 3,763
Concentrations, μg/m3 in the on board vehicle 24 hr study

21. Results (3)
Compound
Poblado,
average
Urban
stationary
average On board
Urban
averages,
stationary and
on board
Rural,
Arvi Park
Type of zone urban urban urban urban rural
n-Nonane 0,792 1,344 1,919 1,536 0,060
n-Decane 0,790 1,532 1,986 1,683 0,046
n-Undecane 0,536 0,977 1,728 1,227 0,038
n-Dodecane 0,338 0,512 0,564 0,529 0,025
n-Tridecane 0,250 0,383 0,730 0,498 0,031
n-Tetradecane 0,229 0,406 1,588 0,800 0,027
n-Pentadecane 0,213 0,599 6,379 2,526 0,057
Naphthalene 0,888 1,579 0,637 1,265 0,139
1-Methylnaphthalene 0,197 0,469 0,322 0,420 0,010
2-Methylnaphthalene 0,397 0,959 0,576 0,831 0,016
Phenanthrene 0,028 0,085 1,279 0,483 0,005
1-Metylphenanthrene 0,000 0,079 0,426 0,195 0,000
2-Methylanthracene 0,000 0,091 0,523 0,235 0,000
Total studied VOC 4,656 9,013 18,657 12,227 0,456
Total studied AH 3,146 5,751 14,894 8,799 0,286
Total estudied PAH 1,510 3,261 3,763 3,428 0,170
Comparative concentrations, μg/m3 in the average urban and rural zones and in
the on board 24 hr samples

22. 0,0
0,2
0,4
0,6
0,8
1,0
1,2
VOCsconcentration,μg/m3
Poblado, 05/08/10 Poblado, 07/08/10 Poblado, 10/08/10
Comparative results for the three samples in El Poblado (urban zone)

23. 0,0
0,5
1,0
1,5
2,0
2,5
VOCsconcentration,μg/m3
Poblado (urban) average Botanical Garden (urban)
Comparative results for the urban stationary samples

24. 0,0
1,0
2,0
3,0
4,0
5,0
6,0
7,0
VOCsconcentration,μg/m3
On Board
Results for the On board moving sample (urban zone)

25. 0,000
0,020
0,040
0,060
0,080
0,100
0,120
0,140
0,160
VOCsconcentration,μg/m3
Arvi Park
Results for the Arvi Park (rural zone)

26. 0
1
2
3
4
5
6
7
VOCsconcentration,μg/m3
Poblado (urban) average Botanical Garden (urban) Arvi Park On Board (urban)
Comparative results for all zones

27. 4,66
13,03
17,71
0,46
0
2
4
6
8
10
12
14
16
18
20
Total VOC
TotalVOCsconcentration,μg/m3
Poblado average (urban) Botanical Garden (urban) On Board (urban) Arvi Park (rural)
Comparative results for all the zones (total VOCs)

28. Compound
Range of
concentrations
in urban areas,
μg/m3
Typical
concentration
in urban areas,
μg/m3
Average of
concentrations
in study urban
areas, μg/m3
Indicator, Value
study/typical
value, urban
n-Nonane 0,07-467 5,06 1,24 0,245
n-Decane 0,16 -1100 18,68 1,33 0,071
n-Undecane 0,15- 59 7,66 0,95 0,124
n-Dodecane 0,0 -160 0,97 0,45 0,469
n-Tridecane 0,18-2,7 0,93 0,40 0,427
n-Tetradecane 0,0 - 36 8,46 0,57 0,068
n-Pentadecane 0,19 - 158 15,47 1,60 0,103
Naphthalene 0,0 - 77 2,27 1,11 0,490
1-Methylnaphthalene 0,00 - 5,1 0,59 0,33 0,557
2-Methylnaphthalene 0,00 - 1,1 0,39 0,66 1,678
Phenanthrene 0,01 - 129 1,08 0,30 0,277
Total studied VOCs 61,58 8,94 0,145
Comparisons with values reported in urban areas around the word

29. Compound
Range of
concentrations
in rural areas,
μg/m3
Typical
concentration
in rural areas,
μg/m3
Concentrations
in study rural
areas, μg/m3
Indicator,
Value
study/typical
value, rural
n-Nonane 0,0 - 58,2 4,07 0,060 0,015
n-Decane 0,0 - 161,2 5,92 0,046 0,008
n-Undecane 0,018 - 0,54 0,28 0,038 0,136
n-Dodecane 0,0 - 0,25 0,04 0,025 0,579
n-Tridecane 0,01-0,12 0,07 0,031 0,479
n-Tetradecane 0,0 - 0,116 0,06 0,027 0,474
n-Pentadecane 0,01 -0,149 0,08 0,057 0,722
Naphthalene - - 0,139 NA
1-Methylnaphthalene - - 0,010 NA
2-Methylnaphthalene - - 0,016 NA
Phenanthrene 0,0 -0,032 0,01 0,005 0,819
Total studied VOCs 10,52 0,46 0,043
Comparisons with values reported in rural areas around the word

30. Comparative results for the study in the diesel motor for the three fuel Sulfur contents
0
100
200
300
400
500
600
700
VOCsconcentration,μg/m3
Motor S=50 ppm Motor S=500 ppm Motor S=2100 ppm

31. Comparative results for the study in the diesel motor for the three fuel Sulfur contents
Compound Motor S=50 ppm Motor S=500 ppm
Motor S=2100
ppm
n-Nonane 177 62 160
n-Decane 407 153 528
n-Undecane 254 203 501
n-Dodecane 199 250 649
n-Tridecane 186 311 586
n-Tetradecane 111 311 450
n-Pentadecane 61 361 356
Naphthalene 179 140 141
1-Methylnaphthalene 87 134 176
2-Methylnaphthalene 170 218 317
Phenanthrene 1,4 13 6
1-Metylphenanthrene 0 0 0
2-Methylanthracene 0 0 0
Total studied VOC 1832 2155 3869
Total studied AH 1395 1650 3230
Total estudied PAH 437 505 639

32. 0
500
1000
1500
2000
2500
3000
3500
4000
4500
0 500 1000 1500 2000 2500
VOCsinexhaustgases,µg/m3
Concentration of sulfur in diesel, ppm
Total VOCs n - dodecane Naphthalene 2-Metylnaphthalene
Influence of diesel fuel sulfur content in VOC emissions

33. 1832
2155
3869
0
500
1.000
1.500
2.000
2.500
3.000
3.500
4.000
4.500
Total VOCs
VOCs,μg/m3
Motor S=50 ppm Motor S=500 ppm Motor S=2100 ppm
Influence of diesel fuel sulfur content in VOC emissions

34. Conclusions
The region atmosphere shows presence of VOCs
The concentrations in urban areas are clearly greater that the ones in rural area. In
the average urban total VOCs were 27 times larger.
The values found in rural and urban areas tend to be smaller that the typical values
reported in the literature. An indicative for total VOCs shows values around 15 % of
the reported typical values for urban areas and about 5 % for rural areas.
The VOC concentrations are related to vehicle emissions, especially to diesel fuel
vehicles emissions.
An initial baseline has been established which should be useful for future work and
public policy in relationship to vehicle related pollution control.
Reducing S content on diesel fuel has been a beneficial step in this direction.

35. Acknowledgements
This work was supported by POLITÉCNICO COLOMBIANO JAIME ISAZA CADAVID
from Medellín, Colombia, and by ECOPETROL, the petroleum company of Colombia.
We acknowledge the Nevada DRI Institute for the analytical and sampling assistance
and support and the University of Antioquia, GIMEL group, for the work done in the
laboratory motor testing.
Tanks you very much for your kind
attention

36. REFERENCIAS
1. http://www.air-quality.org.uk/04.php (Volatile Organic Compounds (VOCs))
2. Mølhave, L. (1991), Volatile Organic Compounds, Indoor Air Quality and Health. Indoor Air,
1: 357–376
3. Sánchez, José M; Alcántara, A., IX,Compuestos orgánicos volátiles en el medio ambiente, en
Anales de la Real Academia Nacional de Farmacia.
http://www.analesranf.com/index.php/mono/article/viewFile/605/622/
4. Wiederkehr, P., Yoon, S.-J., 1998. Air Quality Indicators, in: Fenger, J., Hertel, O., Palmgren,
F.(Eds.), Urban Air Pollution, European Aspects. Kluwer Academic Publisher, Dordrecht, pp.
403-418.
5. Toxicological Profile for Polycyclic Aromatic Hydrocarbons. U.S. DEPARTMENT OF HEALTH
AND HUMAN SERVICES, Public Health Service, Agency for Toxic Substances and Disease
Registry, August 1995
6. National VOC Emission Standards for Aerosol Coatings, 05 November 2009, Wanyu R.
Chan, in http://www.sciencedirect.com/science/article/pii/S0026057609803747
7. J.-Y. Chin, S.A. Batterman / Chemosphere 86 (2012) 951–958, VOC composition of current
motor vehicle fuels and vapors, and collinearity analyses for receptor modeling.
8. Data base for the VOCs, as reported in http://www.ncbi.nlm.nih.gov/
9. Agudelo, J., Corredor, L., Hernández, J., 2000. Simulación del proceso de combustión en
motores de encendido por compresión. Energética. Universidad Nacional de Colombia.

37. REFERENCIAS
10. Assessment and Standards Division Office of Transportation and Air Quality U.S.
Environmental Protection Agency. Technical Support Document: Control of Emissions of
Hazardous Air Pollutants from Motor Vehicles and Motor Vehicle Fuels. EPA420-R-00-023.
December 2000
11. Área Metropolitana del Valle de Aburrá, et al., 2010. Plan de Descontaminación del Valle de
Aburrá. 2010.
12. Barletta, B., Meinardi S., Sherwood F., Chan, C., Wang, X., Zou, S., Chan, L., Blake, D.,
2005.Volatile organic compounds in 43 Chinese cities. Atmospheric Environment 39, 5979-
5990.
13. Center for Environmental Research Information Office of Research and Development U.S.
Environmental Protection Agency, 1999. Compendium of Methodsfor the Determination of
Toxic Organic Compoundsin Ambient Air. Second Edition. Compendium Method TO-17.
14. Chin, J. Y., Stuart, A., Batterman, 2012. VOC composition of current motor vehicle fuels and
vapors, and collinearity analyses for receptor modeling. 86, 951–958.
15. Derwent, R.G., Davies, T.J., Delaney, M., Dollard, G.J., Field, R.A., Dumitrean, P., Nason, P.D.,
Jones, B.M.R., Pepler, S.A., 2000. Analysis and interpretation of the continuous hourly
monitoring data for 26 C2–C8 hydrocarbons at 12 United Kingdom sites during 1996.
Atmospheric Environment 34, 297–312.
16. Environmental Assesment-Washington Office U.S. Environmental Protection Agency. Health
Assesment Document for Diésel Emissions, 1998.

38. REFERENCIAS
17. Gómez, Miryam, et al., 2010. Caracterización y análisis de la Contribución de Fuentes de
Material particulado en la concentración PM2.5, Libro Arte Medellín, Colombia, pp 182.
18. Fenger, J., Hertel, O., Palmgren, F., Wiederkehr, P., 1998: Urban Air Pollution. European
Aspects. Kluwer Academic Publishers, Dordrecht, pp. 403-418.
19. Guo,H., So, K.L.,Simpson, I.J., Barletta, B., Meinardi, S., Blake, D.R.,2007. C1-C8volatile
organic compounds in the atmosphere of Hong Kong: Overview of atmospheric processing
and source apportionment. Atmospheric Environment, 41, 1456-1472.
20. Krieger, Robert K. Report to the Air Resources Board on the Proposed Identification of
Diesel Exhaust as a Toxic Air Contaminant. Part A. Exposure Assessment As Approved by the
Scientific Review Panel on April 22, 1998
21. Lee, C.R., Yoo,C.I., Lee, J.H., Kim,S.R.,Kim, Y., 2002. Hematological changes of children
exposed to volatile organic compounds containing low levels of benzene. Science of The
Total Environment,299, Issues 1–3,237-245.
22. López, G., Estrada, A., 1992. Morfología y composición química de las partículas emitidas
por los automotores a diésel en los grandes centros de población del país. Instituto
Mexicano del Petroleo. México.http://www.bvsde.ops-
oms.org/bvsaidis/caliaire/mexicona/R-0013.pdf
23. Pacheco, J., Franco, J., Behrentz, E., Belalcazar, L., Clappier, A., 2009. VOCs concentrations in
the ambient air of Bogota city: source identification and apportionment. Grupo de Estudios
en Sostenibilidad Urbana y Regional. Universidad de los Andes. Colombia. Escuela
Politécnica Federal de Lausanne (EPFL). Jeune Chercheur Boursier, KFPE, Suiza.

39. REFERENCIAS
24. Pacheco, J., Franco, J., Behrentz, E., Belalcazar, L., Clappier, A., 2009. VOCs concentrations in
the ambient air of Bogota city: source identification and apportionment. Grupo de Estudios
en Sostenibilidad Urbana y Regional. Universidad de los Andes. Colombia. Escuela
Politécnica Federal de Lausanne (EPFL). Jeune Chercheur Boursier, KFPE, Suiza.
25. Parivesh. Hazardous air pollutants. Central pollution control board. Ministry of environment
& forest. "Parivesh Bhawan" East Arjun Nagar, Delhi -
110032.http://www.cpcb.nic.in/upload/Newsletters/Newsletters_64_COVER,%20SOFT,%20
BACK,%20EDITORIAL%20HAPs%20Newsletter.pdf
26. Posada E., Díaz L. La formación de material particulado pm 2.5 en su relación con las
emisiones de vehículos y la química atmosférica. Seminario sobre material particulado y la
calidad de combustibles de automoción. Medellín, 2009
27. Wiederkehr, P. et al, 1998. Urban Air Pollution. European Aspects. Kluwer Academic
Publishers, Dordrecht, pp. 403-418.