Abstract:
Street food vending is part of the informal sector that plays a significant role 10
in improving socio-economic status of vendors and the food security of consumers. 11
However, this sector faces safety challenges mostly due to anthropogenic activities and 12
the lack of regulation. Chemical and heavy metal contamination from agricultural 13
practices and industrial activities are significant concerns. This study aimed to evaluate 14
heavy metal contamination in commonly vended foods-pap, chicken, pork and 15
moroho/salads- in the Free State, South Africa, and assess the associated health risks to 16
consumers. Shapiro-Wilk’s normality test and Kruskal-Wallis H tests were used to 17
evaluate differences between means, followed by Pairwise Comparison (p=0.05). 18
Results indicated heavy metal contamination in all analysed samples. The overall 19
median and IQR of As, Cd, Cr, Cu, Fe, Pb, and Zn in descending order Fe 4.365(4.424), 20
Zn 3.605(3.711), As 2.653(2.971), Pb 1.095(1.266), Cu 0.271(0.326), Cr 0.212(0.117) and Zn
0.023(0.027) mg/kg. Multiple pairwise comparisons showed a statistically significant
difference (p <0.05) for As between all pairs, while other heavy metals showed some
variations without statistical significance. The EDI values of pap, chicken, pork and
moroho/salads were below the recommended dietary values, suggesting the heavy
metals may not pose a public health risk. The health risk assessment through ICLR and
Hazard Index (HI) indicated potential cancer and non-cancer risks from heavy metals
in street-vended foods, as ICLR≥10-3 and HI >1. This implies that habitual consumers
are at risk of non-carcinogenic health conditions
