Investigating the occurence of contaminants of emerging concern in urban slum areas: a case study of Bwaise, Kawempe division, Kampala-Uganda

Abstract

Contaminants of emerging concern (CECs) are defined as chemical compounds discovered in water or environment that are not currently monitored or regulated but are thought to cause adverse effects on the ecosystem and human health. The aim of this study was to investigate the occurrence, distribution, level of concentration, toxicology and risk rankings of four main pharmaceutically/personal care products active compounds (PPCPs) in the urban poor environment. The study was undertaken in Bwaise II &III, Kampala City, Uganda. Possible sources of contaminants of emerging concern were mapped and distances from housing and water sources established. Fifteen (15) water and waste samples were collected from water sources, open drains and solid waste dumping sites and analyses for various elements using the Liquid Chromatography tandem mass spectrometry (LC-MS-MS). The study found more healthcare centers (47%) than pharmacies (40%) and salons as possible sources of contaminants of emerging concern. These were found in low lying areas, mainly located along the main roads at an average distance of 20 metres from households and 20metres from communal water stand taps and protected springs. LC-MS-MS analysis found Paracetamol in communal stand taps, grey water, drainage channel and protected springs, respectively with concentrations of (0.038; 0.017; 0.046 and 0.031ng/ml). Ibrufen was detected in drainage channels (0.0083ng/ml), grey water (0.036ng/ml) protected spring (0.083ng/ml), unprotected spring (0.048ng/ml) and solid waste dump sites (0.285ng/ml). Other personal care products (PCPs) like Dichlovos and Cypermethrin were detected in traceable amounts. Results derived from risk quotient approach established that Ibrufen posed high acute risk of risk quotient (RQ) =1.96. This study recommends proper medical waste management especially from households, furthermore water treatment processes should target CECs and this can be captured at design stage.