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Special Feature
“The message here is that much needs to be done about VOC concentration in our indoor environment, especially those from paint,” Dr Fadeyi concludes. Isolating the issue While the regulations seen in the US and UK are still to be developed locally, the problem isn’t unique to the Middle East. In 2000, principal research scientist Stephen Brown, of Australia’s Commonwealth Scientific and Industrial Research Organisation, conducted a study on Australian homes that revealed tenants were exposed to “up to 20 times the maximum allowable limits of indoor air toxins”. “Identifying these air toxins is part of a world-wide focus on identifying and controlling the cost to human health associated with modern living,” commented Brown. The research also found that such compounds could be present in the atmosphere of newly built of decorated homes, for “at least ten weeks”. “The most potent sources are paints, adhesives and some wood-based panels. Further measurements in 27 suburban Melbourne residences more than a year after construction identified 27 airborne toxics. These included the carcinogens benzene, formaldehyde and styrene, and a cocktail of methanol, ethanol, acetone, toluene, dichlorobenzene plus a number
High incidences have also been recorded in museums, libraries and schools. Extensive research began in the 1970s, with scientists identifying poor ventilation; high temperatures; airborne and chemical pollutants; and ozone produced by photocopiers and printers, as leading culprits. The studies “There are numerous studies from European, North American and East Asian countries addressing this concern,” says Dr Fadeyi. “Despite this, little is known about UAE buildings’ VOC status and there are no conscious efforts or facilities for academics to address this concern. I came to this country more than two years ago and I was baffled about this situation,” he recalls, further commenting on the UAE’s pace of construction. Not only are the hazards of VOC well known, but the effects of using heavy metals have also been documented for millennia, with the ancient Greeks and Romans first documenting side effects in workers. In 370BC, it is said Hippocrates attributed a severe case of colic in a worker who extracted metals to lead exposure and in around AD50, Pliny the Elder recorded that workers painting ships with native ceruse – commonly known as white lead – wore loose bags
February 2012
over their faces to avoid breathing dust they considered to be noxious. Dr Fadeyi conducted investigatory IAQ studies in four air-conditioned office buildings in the UAE, using a handheld atmospheric monitor to measure VOC gas phase concentration, in addition to other toxins. The VOC concentrations recorded varied from 900 to 4500 µg/m3 – the recommended ‘comfort range’ as ascertained in a study by Canadian researcher Molhave, is less than 200µg/m3. Molhave’s study was first published at the fifth International Conference on Indoor Air Quality and Climate held at Toronto, Canada in 1990. During Dr Fadeyi’s research he also measured the toluene concentration, which averaged well above the recommended levels of less than 250 µg/ m3, reaching 1200 µg/m3.
Low VOC/ no VOC ‘No’ VOC does not mean the VOC content of a paint is zero. Regulations state that to be classed as ‘no VOC’, a paint cannot contain more than 5g/litre of VOC. Low VOC products are those that contain less than 50g/litre. Any paint with a VOC concentration of more than 50g/litre is considered to be high VOC.
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