Research Articles

Spatial and temporal assessment of gaseous pollutants in the Highveld of South Africa

Alexandra S. Lourens, Johan P. Beukes, Pieter G. van Zyl, Gerhardus D. Fourie, Johanna W. Burger, Jacobus J. Pienaar, Colin E. Read, Johan H. Jordaan
South African Journal of Science | Vol 107, No 1/2 | a269 | DOI: | © 2011 Alexandra S. Lourens, Johan P. Beukes, Pieter G. van Zyl, Gerhardus D. Fourie, Johanna W. Burger, Jacobus J. Pienaar, Colin E. Read, Johan H. Jordaan | This work is licensed under CC Attribution 4.0
Submitted: 13 May 2010 | Published: 28 January 2011

About the author(s)

Alexandra S. Lourens, North West University, Potchefstroom campus, South Africa
Johan P. Beukes, North West University, Potchefstroom campus, South Africa
Pieter G. van Zyl, North West University, Potchefstroom campus, South Africa
Gerhardus D. Fourie, Sasol Technology, Sasolburg, South Africa
Johanna W. Burger, Sasol Technology, Sasolburg, South Africa
Jacobus J. Pienaar, North West University, Potchefstroom campus, South Africa
Colin E. Read, North West University, Potchefstroom campus, South Africa
Johan H. Jordaan, North West University, Potchefstroom campus, South Africa

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Diverse natural and anthropogenic activities in the Highveld of South Africa contribute to elevated levels of inorganic and organic gaseous pollutant species. The primary aims of this investigation were to determine spatial and temporal distributions of nitrogen dioxide (NO2), sulphur dioxide (SO2) and ozone (O3), as well as benzene, toluene, ethylbenzene and xylene (BTEX) in this area. Sampling was conducted on a monthly basis for a year at eight strategically selected sites. The highest NO2, SO2 and BTEX concentrations were measured at sites with significant local sources and/or sites impacted by more remote sources, as indicated by overlay back trajectories. O3 concentrations were found to be lower at sites with high levels of NO2, SO2 and BTEX. NO2 and SO2 peaked during winter, while O3 peaked in spring. NO2 and SO2 temporal concentration variations were ascribed to differences in seasonal meteorological conditions, as well as additional sources in winter. The O3 peak coincided with a seasonal CO peak, which was identified as an important precursor for O3 formation. No distinct seasonal trend was observed for BTEX. The annual average concentrations for SO2, NO2, O3 and benzene were below the South African annual standards at all sites.


BTEX; NO2; SO2; O3; passive; sampling; spatial; temporal distributions


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Dabrowski JM, Ashton PJ, Murray K, Leaner JJ, Mason RP. Anthropogenic mercury emissions in South Africa: Coal combustion in power plants. Atmos Environ. 2008;42(27):6620–6626. doi:10.1016/j.atmosenv.2008.04.032

Freiman MT, Piketh SJ. Air transport into and out of the industrial Highveld Region of South Africa. J Appl Meteorol. 2002;42(7):994–1002. doi:10.1175/1520-0450(2003)042<0994:ATIAOO>2.0.CO;2

Reisell A, MacDonald C, Roberts P, Arey J. Characterization of biogenic volatile organic compound and meteorology at Azusa during the SCOS97-NARSTO. Atmos Environ. 2003;37(Suppl 2):181–196. doi:10.1016/S1352-2310(03)00390-X

Atkinson R. Atmospheric chemistry of VOCs and NOx. Atmos Environ. 2000;34(12–14):2063–2101. doi:10.1016/S1352-2310(99)00460-4

Parra MA, Elustondo D, Garrigo J. Spatial and temporal trends of volatile organic compounds (VOC) in a rural area of northern Spain. Sci Tot Environ. 2006;370(1):157–167. doi:10.1016/j.scitotenv.2006.06.022, PMid:16899278

Hoque RR, Khillare PS, Agarwal T, Shridhar V, Balachandran S. Spatial and temporal variation of BTEX in the urban atmosphere of Delhi, India. Sci Tot Environ. 2007;392(1):30–40. doi:10.1016/j.scitotenv.2007.08.036, PMid:18067950

Paoletti E, Bytnerowicz A, Andersen C, Augustatitis A. Impacts of air pollution and climate change on forest ecosystems – emerging research needs. Sci World J. 2007;7(Suppl 1):1–6.

Felzer BS, Cronin T, Reilly JM, Melillo JM, Wang X. Impacts of ozone on trees and crops. C R Geoscience. 2007;339:784–798. doi:10.1016/j.crte.2007.08.008

Bernstein JA, Alexis N, Barnes C, et al. Health effects of air pollution. J Allergy Clin Immunol. 2004;114(5):1116–1123. doi:10.1016/j.jaci.2004.08.030, PMid:15536419

Kampa M, Castanas E. Human health effects of air pollution. Environ Pollut. 2007;151(2):362–367. doi:10.1016/j.envpol.2007.06.012, PMid:17646040

Ma W, Shaffer KM, Pancrazio JJ, et al. Toluene inhibits muscarinic receptor-mediated cytosolic Ca2+ responses in neutral precursor cells. Neurotoxicol. 2002;23(1):61–68. doi:10.1016/S0161-813X(01)00084-5

Notice of intention to declare the Highveld Priority Area in terms of Section 18(1) of the National Environmental Management: Air Quality Act, 2004. Act no. 39 of 2004. Proclamation no. 396, 2007.

Toenges-Schuller N, Stein O, Rohrer F, et al. Global distribution pattern of anthropogenic nitrogen oxide emissions: Correlation analysis of satellite measurements and model calculations. J Geophys Res. 2006;111(D05312):1–15.

Martins JJ, Dhammapala RS, Lachmann G, Galy-Lacaux C, Pienaar JJ. Long-term measurements of sulphur dioxide, nitrogen dioxide, ammonia, nitric acid and ozone in southern Africa using passive samplers. S Afr J Sci. 2007;103(7–8):336–342.

Carmichael GR, Ferm M, Thongvoonchoo N, et al. Measurements of sulfur dioxide, ozone and ammonia concentrations in Asia, Africa and South America using passive samplers. Atmos Environ. 2003;37(9–10):1293–1308. doi:10.1016/S1352-2310(02)01009-9

Josipovic M. Acidic deposition emanating from the South African Highveld– a critical levels and critical loads assessment. PhD thesis, Johannesburg, University of Johannesburg, 2009.

Dhammapala RS. Use of diffusive samplers for the sampling of atmospheric pollutants. MSc thesis, Potchefstroom, North West University, 1996.

United States Environmental Protection Agency. Compendium methods for the determination of toxic organic compounds in ambient air. 2nd ed. Compendium method TO-17. Determination of volatile organic compounds (VOCs) in ambient air using active sampling unto sorbent tubes. Cincinnati: United States Environmental Protection Agency; 1999.

Skov H, Lindskog A, Palmgren F, Christensen CS. An overview of commonly used methods for measuring benzene in ambient air. Atmos Environ. 2001;35(Suppl 1):141–148. doi:10.1016/S1352-2310(00)00512-4

Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT), Version 4.8, [cited 2009 Dec 4]. Available from:

MATLAB 7.8.0, Mathworks, Massachusetts, USA, [cited 2009 Nov 21]. Available from:

Valente RJ, Imhoff RE, Tanner RL, et al. Ozone production during an urban air stagnation episode over Nashville, Tennessee. J Geophys Res. 1998;103(D17):22555–22568. doi:10.1029/98JD01641

Martins JJ. Concentrations and deposition of atmospheric species at regional sites in southern Africa. PhD thesis, Potchefstroom, North West University, 2008.

Seinfeld JH, Pandis SP. Atmospheric chemistry and physics: From air pollution to climate change. New York: Johan Wiley & Sons, 1998; p. 66259.

Garstang M, Tyson PD, Swap R, Edwards M, Kallberg P, Lindesay JA. Horizontal and vertical transport of air over southern Africa. J Geophys Res. 1996;101(D19):23721–23736. doi:10.1029/95JD00844

Jacob DJ. Heterogeneous chemistry and tropospheric ozone. Atmos Environ. 2000;34:2131–2159. doi:10.1016/S1352-2310(99)00462-8

Laakso L, Laakso H, Aalto PP, et al. Basic characteristics of atmospheric particles, trace gases and meteorology in a relatively clean southern African savannah environment. Atmos Chem Phys. 2008;8:4823–4839. doi:10.5194/acp-8-4823-2008

Swap RJ, Annegarn HJ, Suttles JT, et al. Africa burning: A thematic analysis of the South African Regional; Science Initiative (SAFARI 2000). J Geophys Res. 2003;108(D13):8465–8480. doi:10.1029/2003JD003747

Zunckel M, Venjonoka K, Pienaar JJ. Surface ozone over South Africa: Synthesis of monitoring results during the cross border air pollution impact assessment project. Atmos Environ. 2004;38:6139–6147. doi:10.1016/j.atmosenv.2004.07.029

Diab RD, Thompson AM, Mari K, Ramsay L, Coetzee GJR. Troposheric ozone climatology over Irene, South Africa, from 1990 to 1994 and 1998 to 2002. J Geophys Res. 2004;109(D20301):1–11.

National Environmental Management Air Quality Act of 2004 section 63. Government Gazette Republic of South Africa. 534:8–9. c2004 [cited 2009 Dec 24]. Available from:

Van der Walt HJ. The impact of hydrocarbon emissions on regional air quality in a South African metropolitan area. PhD thesis, Potchefstroom, North West University, 2009.

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