Assessment of polycyclic aromatic hydrocarbons in the breast milk of mothers from Kampala capital city, Uganda

Abstract

The aim of this study was to investigate levels of polycyclic aromatic hydrocarbons (PAHs) in breast milk samples from healthy mothers who have lived in Kampala capital city (urban and industrialized area) for more thancarcin five years. In this study, the rural areas of Nakaseke District were used as a control site for comparison purposes. A total of sixty samples (30 from Kampala and 30 from Nakaseke) were collected between February and October 2019. The samples were extracted using liquid-liquid extraction and clean-up was performed on silica column. Analysis of the samples was done using Gas chromatography triple quadrupole (GC-MS/MS). Total concentration of thirteen PAHs (∑13PAHs) in the samples was 283.74 and 29.63 ng g-1 lipid weight in Kampala and Nakaseke, respectively. The levels of PAHs in Kampala were significantly higher than those from Nakaseke (p<0.05, Mann-Whitney U test). Low molecular weight PAHs (LPAHs) were more predominant than high molecular weight PAHs (HPAHs). Naphthalene was the most abundant and frequently detected PAH (90.0%) followed by acenaphthene (81.7%), fluorene (81.7%) and fluoranthene (81.7%). In the present study, risk assessment for carcinogenicity and mutagenicity on contaminated breast milk was 7.7×10−4 and 6.3×10−4, respectively. This means that approximately 8 and 6 out of 10,000 infants breast fed in Kampala may have cancer and non-cancer related adverse diseases, respectively during their life time as a result of taking breast milk contaminated with PAHs, thus suggesting a negligible risk. Therefore, the breast milk of mothers from Kampala is safe for the infant.