Five sites in the the Durban Metropolitan Area (DMA) were monitored for pollen over a period of approximately six months. Monitoring commenced in the beginning of October 1996 and ended at the end of April 1997. Five Burkard Seven-day Samplers were located in secure sites in Pinetown, Chatsworth, Wentworth, Durban North and Glenwood. At the end of each week the pollen sample was sent to a laboratory in Johannesburg where the pollen content was analysed and recorded.

Results showed that total pollen counts were never very high, with the greatest number recorded in February. December showed a decrease at all sites, while the decline in April indicates the end of the summer flowering season. There was some variability among the sites, with highest counts generally found in Durban North. This reflects a difference in localised vegetation.

The types of pollen which occurred most frequently were Poaceae (various grasses) and Cannabis (dagga). Other plants recorded in very small numbers were Acacia (both Australian and South African), Chenopodiaceae (pigweed family), Compositae (daisy family), Cyperaceae (sedge), Myrtaceae (bluegum family), Pinus, Ulmus (elm) and Urtica (nettle).

Most of these are allergenic, but the low numbers indicate that pollen was not a major cause of respiratory ailments in Durban during this particular study-period. For any one pollen type to constitute an allergy risk, it must be present at levels of between 30 and 50 grains.m^-3 daily. This study showed that daily counts for all pollen types combined never exceeded this level. It is possible that pollen allergy may have occurred in localised situations, where there was an abundance of the plant types mentioned above.

Previous studies conducted in the DMA have shown that there can be tremendous inter-annual variation in pollen counts. In some past years daily counts of individual types (especially grass and dagga) often exceeded the limit of 30-50. This variability is due to the role of weather conditions: they influence both the amount of pollen which plants produce, and also the amount which becomes air-borne. For this reason it is difficult to categorically state that the DMA is either a high- or low-risk area, in terms of pollen allergy. When available data are averaged over several years, the tendency is towards a low-risk classification.

Possibly of greater importance in the DMA is the observation that fungal and house-dust mite allergies are more prevalent than pollen, and also more significant than in any other part of the country. Therefore these aeroallergens probably affect more people in the DMA than does pollen.