Multifactorial Safety Assessment of Raw Milk in Shiraz, Iran: Adulteration, Microbial Contamination, and Toxicological Hazards Publisher



Alimohammadi A ; Azari R ; Arab MS ; Berizi E
Source: Food Control Published:2026

Abstract

With the recent surge in milk consumption in developing countries, ensuring milk safety and quality is now more critical than ever. This study assessed the safety and quality of raw milk produced by farms near the city of Shiraz, Iran. Raw milk was assessed in terms of possible adulteration, freshness, storage temperature, microbial contamination, levels of heavy metals, AFM1, and the presence of antibiotic residues. The results showed that large-scale milk producers are far less likely to deliver low-quality milk or adulterate it compared to small-scale ones. In addition, insufficient cooling can be blamed for the rather high microbial contamination in milk. A total of 654 out of 658 milk samples (99.39%) were stored at temperatures above 4 °C. Fortunately, based on risk assessment results, there were no immediate or long-term risks related to milk consumption for consumers. This applied to the levels of arsenic, lead, cadmium, and mercury, as well as AFM1 contamination. The hazard quotients (HQs) for all heavy metals were well below 1. AFM1 was detected in 70% of samples at an average concentration of 0.034 μg/kg, but none exceeded the national standard. Also, antibiotic residues were negligible, with only 7 samples (1.06%) testing positive for β-lactams, thus relieving concerns about potential allergenic hazards to consumers. These results suggest that although there are some legitimate concerns about milk safety in Shiraz, they can be addressed through proper milk handling and cooling, as well as stricter inspection of milk safety in small-scale farms. Thus, consumers can drink a glass of milk safely when the dairy industry and regulatory authorities exercise full oversight. © 2026