Materials used by dental technicians in South Africa.

In order to determine the choice of materials used by dental technicians, questionnaires were sent to 400 registered South African dental laboratories. The response rate was 30.5 per cent. The most frequently used brands were identified. The relationship between usage of materials and demographic variables is discussed.

Exposure to air pollution from transitional household fuels in a South African population.

Exposure to high levels of particulate matter is one of the risks associated with a household utilizing low quality coal as primary household energy source. In South Africa more than 20 million people rely on traditional (wood) and transitional (coal and paraffin) fuels to fulfil their basic energy needs--cooking and space heating. Personal exposures to TSP in a coal burning Township in the Vaal Triangle (central South Africa) were determined during the winter and summer of 1991 and 1992. Personal monitoring of TSP were conducted over a 12 hour period. Forty five children, age 8-12, participated. Exposures varied from 294 to 2304 micrograms/m3. The average 12 hour exposure during a summer day (8:30 a.m.-8:30 p.m.) was 662 micrograms/m3 (N = 15) compared to 1333 micrograms/m3 for a winter school day (N = 13). The difference was highly significant (P < 0.0002). The study identified the following risk factors associated with exposure: season (winter higher than summer), gender (boys higher than girls), and day of the week (school days higher: schools are situated in the centre of completely unelectrified areas). Statistical significant difference between personal exposures to TSP were documented between electrified vs unelectrified (utilize coal only) areas. The study confirmed other reports of extremely high exposures to air pollution documented in developing communities across the globe.