A comparison of particulate matter (PM101) in industrially exposed and non exposed communities.

Abstract

BACKGROUND For many years, the Durban south community has raised concerns about ambient air pollution including particulate matter. The Durban South Industrial Basin (DSIB) may be high risk for exposure to significant levels ofPMI0 due to its geographic relationship with two major petroleum refineries, together with a pulp and paper manufacturing facility. While potential sources of elevated levels of PMlOin the south are industrial, the north is likely to be exposed to controlled burning of vacant fields and use ofbiomass fuels, particularly in informal settlements. Adverse health effects from particulate matter (PM) were well documented by extensive epidemiological observations by animal and human studies, following laboratory exposures. Studies across a variety of environmental settings have demonstrated a strong association between ambient air particulate matter (PMlO) and cardiopulmonary morbidity and mortality. Studies have reported that particulate matter is associated with adverse health effects resulting from inflammatory responses in the lower respiratory tract. Exposure to particulate matter may increase the risk of lung cancer. Some studies suggested that small temporal increases in ambient particulate matter are sufficient to cause health impacts. Other studies attributed strong seasonality to temperature inversions associated with temperature changes. Studies also illustrated the impact of temporal variation on PMl 0 levels across regions. OBJECTIVES The main objectives of this study were to determine and compare the levels of ambient PMIO in industry exposed and non-industry exposed communities, to determine temporal variation and to make recommendations. METHODS This study focused on determining the 24-hour ambient PMI0 levels in the Durban south community. The PMIO levels in Durban south (industry exposed) were compared with the PM10 levels in an area north of Durban (non-industry exposed). Relevant data obtained from the monitoring program of the South Durban Health Study (SDHS) was reviewed for the purposes of this study. The different techniques used to measure PMI0 are gravimetric sampling and tapered elemental oscillating microbalance (TEaM). Both methods were used to collect PMI0 data. The data comprised of quantitative and categorical variables. The dependent variable was the PM10 values and the independent variable was the sampling sites. Non-parametric tests were used to analyse the data. RESULTS PMI0 was recorded in all sites in north and south areas. The levels varied across all sites. Both the north and south areas recorded high PMI0 values at regular intervals. No particular trend was observed when the 24 hour PM10 concentration was compared against the standard. All sites recorded medians that were generally in the region of 40-S0,ug/m3. The site with the highest median (SIA,ug/m3 ) was Assegai. Briardale recorded the lowest median (34.9,ug/m3 ). Exceedances of the South African National Standard code 1929 maximum 24-hour concentrations of7S,ug/m3 were observed across all sites. Overall there were 163 (16.7 % of all samples) exceedances, and these ranged widely between the various sites, with no particular regional trend. Overall .June experienced the highest PMl 0 values. No differences in seasonal trends were observed in north and south. CONCLUSION On average the levels ofPMI0 do not exceed national or international standards. The findings did not reveal any statistical difference in exposure levels between the industry exposed and non-industry exposed areas.