An overview of the occurrence, evaluation and remediation of petroleum hydrocarbon contamination in South Africa: case studies of contamination from filling stations in Gauteng

Abstract

Petroleum hydrocarbon compounds are processed into many products including diesel, petrol, paraffin and lubricants. These products are used by ordinary South Africans on a daily basis as they go about their lives. However, some petroleum hydrocarbon compounds, like benzene, used as ingredients in the manufacturing of petrol, are known carcinogens and may increase the risk of cancers, such as lung, skin and bladder cancers (Konečnýet al., 2003, World Health Organisation, 2010, Kpone et al., 2015andIffis et al., 2017),or are otherwise hazardous and may compromise human and ecological health(Chilcott, 2007). Urbanisation and economic growth have significantly accelerated motorisation in South Africa. Van der Post (2017) reports that at the end of February 2017theSouth African electronic National Administration Traffic Information System (eNatis) had a total of 12 027 860 registered vehicles. Of these, approximately 4.6 million were registered in Gauteng, 1.9 million in the Western Cape and 1.6 million in KwaZulu-Natal. Each of these 12 million vehicles uses either diesel or petrol as fuel. Because of the carcinogenic petroleum hydrocarbon compounds contained in and used in the manufacture of diesel and petrol, the National Environmental Management Act 107 of 1998 classifies diesel and petrol as dangerous goods, for which authorisation must be granted by a competent authority for their handling and storage (Government of the Republic of South Africa, 1998). Despite the legislation in place, accidental releases of diesel and petrol may occur during storage, handling and transportation. The accidental releases may be due to leaking storage tanks, spillages during vehicle refuelling, tank overfills, pipeline leakages and bulk fuel tanker road accidents. Accidental releases may result in petroleum hydrocarbon contamination of environmental receptors like soil, surface water, groundwater and air. Human exposure to contaminated receptors may lead to cancer or an otherwise comprised health including narcosis, rapid unconsciousness, chemical pneumonitis, eye and respiratory system irritation, aplastic anaemia, reduced resistance to infections, a variety of dermatitic conditions and neurological disorders (Chilcott, 2007;Sellappa et al., 2010 &World Health Organisation, 2010)