Investigation of Arsenic Airborne in Particulate Matter around Caterers’ Wood Fires in the Cape Town Region

Abstract

Smoke from wood fires has long been recognized as a significant health hazard. Our recent work has reported on the occurrence of waste timber previously treated by chromated copper arsenate (CCA) insecticide in the fuel supplies of informally operating caterers in the Cape Town region. The main objective of this paper is to report evidence that the burning of CCA-treated wood by informal caterers does lead to arsenic enrichment of the smoke.Atmospheric particulate matter with aerodynamic diameter ≤ 10 μm (PM 10 ) was collected using an Air Metrics MiniVol portable aerosol sampler onto quartz filters for durations varying from 1 h to 4 h, at 5 L/min. Smoke was first sampled under controlled conditions, in which CCA-treated samples (of hazard classes H5 and H2) and two untreated wood samples were burned. 18 field samples were collected, from Nyanga, Langa and Khayelitsha (Cape Town) and Kayamandi (Stellenbosch). The PM 10 concentrations were calculated and the smoke samples were microwave-digested using nitric acid for metals analysis by ICP-AES.Under controlled conditions, the concentrations of arsenic volatilised from (H2 and H5) were 19 and 52 μg/m 3 , and the As:Cu and As:Cr ratios strongly increased compared the ratios found in the timber. The lowest concentration of PM 10 was found around the Nyanga taxi rank at a distance of ± 100 m from caterers, at 33 μg/m 3 , while the highest concentration was 8139 μg/m 3 for a 1-hour sample representing occupational exposure close to wood burning fires. Arsenic was detected in 15 smoke samples. The average arsenic level of positive samples was 1.3 μg/m 3 . The arsenic levels measured exceed normal background levels, which have been reported by the WHO to be 0.02-4 ng/m 3 in rural air and up to 30 ng/m 3 in urban air.

The environmental impacts and health hazards of abandoned boats in estuaries

“…Reports suggest that some boats are deliberately burned as a means of 'disposal' or through vandalism (Stevenson, undated;Eklund, 2014). However, as inferred from our observations above, boaters and other members of the public appear to be sampling parts of the hull, deck and interior of abandoned boats in the region under study for firewood; if used for domestic heating, householders will be at serious risk of inhaling significant quantities of toxic chemicals as the wood is burnt (Niyobuhungiro and Blottnitz, 2013).…”

Evaluation of the Changes of the Concentration, Composition and Possible Sources of Size-Resolved Particulate Matter between 2010 and 2011 in a Western Chinese Mega City

“…Atmospheric particulate matter (PM), which has been studied by numerous researchers, is an important air pollutant in many large cities (Zheng et al, 2005;Moorhouse, 2007;Thurston et al, 2011;Niyobuhungiro and Blottnitz, 2013;. A large amount of PM not only affects visibility and causes acidification but also has adverse effects on human health, such as increased respiratory and cardiovascular symptoms and diseases (Harrison and Yin, 2000;Tie et al, 2009;Cheng et al, 2012;Vernile et al, 2013).…”

The food environment and health in African cities

“…In addition to the risks to the safety of the food, many risks are associated with producing and preparing food, for example those from using 'heat generated by unprocessed biofuels and residual oil products' (Clancy, 2008: 467). The use of waste timber for wood fuel can also expose those who cook food with it to high levels of arsenic (Niyobuhungiro and von Blottnitz, 2013).…”