Street foods exacerbate effects of the environmental burden of polycyclic aromatic hydrocarbons (PAHs) in Nigeria

Abstract

Polycyclic aromatic hydrocarbons (PAHs) are a large group of well-known toxicants with carcinogenic potential and other health effects including on the immune system. The high health risks of non-communicable diseases and relevant comorbidities in Africa, particularly in contaminated areas like e-waste and crude oil and gas exploration areas and for high consumers of food commodity groupings which are most critical for PAH exposure, are exacerbated by dietary exposure due to unsafe practices in commonly consumed foods, like those street vended.

In February 2016, 20 commonly consumed street foods were purchased directly from vendors at major bus stops in Benin City and Umunede in Nigeria. The concentration of 16 priority PAHs was determined. The dietary intake of B[a]P, ∑PAH, PAH4, PAH8, and ∑B(a)P_eq was estimated for children, peripubertal children/adolescent, and adult using the total diet study (TDS) method. Among the analyzed PAHs, there was a predominance of chrysene (17.42 μg/kg). Roasted yam (14.15 μg/kg) and fried fish (1.40 μg/kg) had the highest levels of ∑PAH and B[a]P, respectively. The mean concentration of B[a]P, ∑PAH, PAH4, PAH8, and ∑B(a)P_eq ranged from 0.65–1.40 μg/kg, 0.20–14.15 μg/kg, 0.43–5.22 μg/kg, 0.13–7.88 μg/kg, and 0.002–2.123 μg/kg, respectively. The mean concentration of B[a]P and PAH4 reported in this study was below the maximum allowable levels of 5 and 12 μg/kg for adults and above the maximum levels for young children set at 1.0 μg/kg for both B[a]P and PAH4 in food. The estimated dietary intake of B[a]P, ∑PAH, PAH4, PAH8, and ∑B(a)P_eq for adult, adolescent, and children was 0.56, 0.37, and 0.31 μg/day; 17.6, 10.7, and 8.81 μg/day; 5.78, 4.01, and 3.26 μg/day; 9.22, 6.19, and 5.09 μg/day; and 1.72, 0.97, and 0.82 μg/day, respectively.

Street foods represent one important source of PAHs. The exposure occurring through street food compounds with that from home-made foods, environmental pollution, and lifestyle (tobacco smoke) is making up an aggregate daily exposure in the general population.

The incremental lifetime cancer risk for adults and children from the consumption of street food was 7.6 × 10⁻⁸ and 2.1 × 10⁻⁸, respectively. Along with initiatives to manage environmental contamination and promote healthier lifestyle, people should be empowered on healthy cooking practices and safe food cookery environments.