Determination of Nitrate and Nitrite Levels in Preserved Meat Products Sold in Supermarkets in Port Harcourt, Rivers State

Nitrates and nitrites are commonly used as preservatives in processed and cured meat products to inhibit bacterial growth and maintain colour. However, excessive dietary intake of these compounds, particularly nitrites, is associated with methaemoglobinaemia in infants and the potential formation of carcinogenic N-nitrosamines. This study determined nitrate and nitrite concentrations in eight processed meat products including sausages, hot dogs, and smoked meats purchased from supermarkets in Port Harcourt, Rivers State. Nitrate and nitrite levels were quantified using the Griess reagent spectrophotometric method at 540 nm after reduction of nitrate to nitrite by cadmium sulphate. Results were compared with European Union and WHO maximum permissible limits. Nitrite concentrations ranged from 42 to 187 mg/kg across the tested products, with two sausage brands exceeding the EU limit of 150 mg/kg. Nitrate levels were within acceptable ranges in all products. Smoked fish-based products had lower nitrite concentrations compared to pork and chicken sausages. The variation in additive concentrations between brands suggests inconsistent quality control practices among processed meat manufacturers. Given the potential health implications of nitrite overconsumption, particularly for young children, the study recommends regular post-market surveillance of preservative levels in processed meats and enhanced regulatory scrutiny of manufacturing practices in Nigeria's food industry. Keywords: nitrates, nitrites, processed meat, Griess reagent, Port Harcourt.