Dioxin levels in cattle hide processed using different fuel sources for human consumption in Sokoto Central Abattoir, Sokoto State, Nigeria

Introduction: The practice of using tyres to singed hide has been a daily occurrence in most of the abattoirs in Nigeria including Sokoto. This practice exposes meat/hide to hazardous toxic compounds such as heavy metals, polyaromatic hydrocarbons, dioxins and furans. This study aimed to determine the baseline concentrations of dioxins in the hide of slaughtered cattle, and also to determine the contributions of processing methods to dioxins content in cattle hide. Methods: A quasi-experimental study was carried out involving the collection of 160 cattle hide samples through systematic random sampling.: The samples were evenly distributed across the three groups: Tyre, Plastic, and Firewood. Each group was further divided into two subgroups: Control and Test. The sample allocation was as follows: - Tyre group: 54 samples (27 Control, 27 Test), Plastic group: 53 samples (26 Control, 27 Test) and Firewood group: 53 samples (26 Control, 27 Test). These were then processed using a variety of materials, specifically tyres, plastic or nylon bags, and firewood, to evaluate the differential effects of each. An Enzyme-Linked Immunosorbent Assay (ELISA) was used to analyse samples from the processed hides. Results: The concentration of dioxin in the control groups was found to be 0.679ppt , 0.263ppt and 0.501ppt for tyres, plastics and firewoods respectively which were all within the normal range set by WHO/FAO at 0.0001 to 1.0parts per trillion, while for the other groups, it was above, with those processed using tyres having the highest concentration ranging from 1.30- 25.62ppt. The level of concentration of dioxin was compared using the Paired T-test statistical method and the concentration was statistically significant for hide processed using tyres at p=0.004. The result was also statistically significant using ANOVA at a p-value of 0.015, and a post-hoc test shows that it was significant between tyres and plastics at a p-value of 0.017. Conclusion: The concentration of dioxins significantly increased in hide samples processed using tires beyond the WHO/FAO acceptable levels. And therefore there is need for Government regulatory agencies to enforce food safety laws that will protect the public from the practices of using tires to singe hides.