Carcinogenic and non-carcinogenic health risk assessment of heavy metals in the offal of animals from Felele Abattoir, Lokoja, Nigeria

Abstract

The consumption of metal-contaminated offal of animals will affect the health of humans. Thus, the research determined the concentrations of heavy metals in the offal and muscle tissues of cows, goats, and ram slaughtered at the main abattoir in Lokoja, northcentral Nigeria. Furthermore, an evaluation was carried out to assess the potential health hazards faced by the indigenous population due to the consumption of heavy metals from these animals. The mean concentrations of metals (Al, Cd, Cr, Ni, and Pb) in the kidney, liver, and muscle of cows, goats, and rams were determined using Inductively Coupled Plasma Optical Emission Spectrometry. Estimated daily intake of the metals, hazard quotient, hazard index, and cancer risk were calculated. All internal organs had Ni levels above the regulatory threshold limit. The average concentration of Pb in the muscle tissue and liver of the tested animals exceeded the permissible limits by the WHO. Similarly, the concentration of Cd in the muscle tissues was above the Maximum Permissible Limit (MPL) of 0.05 mg kg−1. Except for cow kidneys, all internal organs contain Cr levels below the MPL (1.0) limit. The THQ value for the metals was < 1 except Cd. It indicates potential health risks due to Cd. The calculated HI values were > 1. The percentage contribution of Cd to the HI value was the highest. The observed sequence is Cd > Ni > Cr > Pb > Al. The results show that eating the offal and muscle under investigation has a carcinogenic effect.