Trace metals potential human health risks assessment through consuming common food spices in Ado Ekiti, Southwest, Nigeria

Background

The safety of food, especially among developing countries like Nigeria, is increasingly becoming a genuine call for concern due to food contamination. While culinary spices are often used for their flavour and colouring capabilities, they also contain significant trace minerals that may be harmful to human health.

Objectives

This study aimed to assess the concentrations of trace minerals, including Iron (Fe), Chromium (Cr), Lead (Pb), Cadmium (Cd), and Arsenic (As), in commonly used spices in Ado Ekiti, Nigeria. Additionally, it sought to evaluate the potential health risks associated with these concentrations.

Methods

The research employed an Atomic Absorption Spectrophotometer (AAS) to detect trace minerals like iron (Fe), chromium (Cr), lead (Pb), cadmium (Cd), and arsenic (As) present in commonly consumed spices in Ado Ekiti, Nigeria. The assessment involved various methods such as Estimation of Daily Intake (EDI), Hazard Quotient (THQ), Total Hazard Quotient (TTHQ), and Cancer Risk (CR).

Results

The results indicated that iron (Fe) levels varied from 0.62 mg/kg in dry onion to 210.40 mg/kg in turmeric, with an average concentration of 45.09±59.83 mg/kg. Chromium (Cr) concentrations ranged from non-detectable (ND) to 0.72 mg/kg, with an average value of 0.1 ± 0.16 mg/kg. All the Cr concentrations were higher than the regulatory limits. The Pb concentration in the spices varied between ND to 0.10 mg/kg with a mean concentration of 0.03±0.03 mg/kg. Scent leaf, bay leaf, dry suya powder, Maggi powder, dry onions, cinnamon, alligator pepper and onion leaf had Pb contents above the permissible level. EDI follows the order: Fe > Cr > Pb > Cd > As. EDI for Cr (0.133 mg/kg) exceeded the reference dose (RfD). All other spices had their THQ for Cr > 1 except for cayenne pepper and dry onions. Scent leaf, curry, bay leaf, thyme, turmeric, black pepper, garlic, Cameroun pepper and alligator pepper had THQ for Pb>1.

Conclusion

All the spices showed TTHQ > 1 except dry onions, with TTHQ <1, an indication of the adverse effects of these spices on consumers in Ado Ekiti, Nigeria. Comprehensive research, such as a risk assessment to understand the spice's vulnerabilities, product type, and history, should be given priority.