Abstract:
Dust storms are meteorological hazards associated with several adverse health impacts
including eye irritations, respiratory and cardiovascular disorders, and vehicular road accidents due
to poor visibility. This study investigated relations between admissions from a large, public hospital
that serves people living in Northern Cape and Free State provinces, South Africa during 2011 to 2017,
and meteorological variables (temperature and air quality) during two dust storms, one in October
2014 (spring) and the second in January 2016 (summer), identified from the media as no repository
of such events exists for South Africa. Distributed nonlinear lag analysis and wavelet transform
analysis were applied to explore the relationships between hospital admissions for respiratory and
cardiovascular diseases, eye irritation, and motor vehicle accidents; maximum temperature, and two
air quality ‘proxy measures,’ aerosol optical depth and Ångström exponent, were used as groundbased air quality data were unavailable. Eye irritation was the most common dust-related hospital
admission after both dust storm events. No statistically significant changes in admissions of interest
occurred at the time of the two dust storm events, using either of the statistical methods. Several
lessons were learnt. For this type of study, ground-based air quality and local wind data are required;
alternative statistical methods of analysis should be considered; and a central dust storm repository
would help analyze more than two events. Future studies in South Africa are needed to develop a
baseline for comparison of future dust storm events and their impacts on human health.
