Aflatoxin M1 in Raw Milk, Pasteurized Milk and Cottage Cheese Collected along Value Chain Actors from Three Regions of Ethiopia

Abstract

Milk is a highly nutritious and perfect natural food for humans. However, when lactating animals feed on Aflatoxin B1 (AFB1)-containing feed, the hydroxyl metabolite aflatoxin M1 (AFM1) contaminates the milk and dairy products. The objective of the current study was to assess the level of AFM1 in raw milk, normally pasteurized milk and Ethiopian cottage cheese collected from value chain actors (producers, collectors, processors and retailers). Cross-sectional study and simple random techniques were used to collect primary samples. A total of 160 composite samples was collected; raw milk (n = 64), pasteurized milk (n = 64) and cheese (n = 32) was analyzed. Quantitative analysis of AFM1 was conducted using enzyme-linked immunosorbent assay (ELISA). The results indicate that AFM1 was detected in all milk products. Results along value chains show that the concentration of AFM1 in raw milk from collectors was significantly higher than from producers, and in pasteurized milk from processors and retailers (p < 0.05). However, no significant (p > 0.05) difference was observed in cottage cheese value-chain actors in all regions. Comparison of AFM1 mean values among all dairy products shows that raw milk had a significantly higher concentration of AFM1 followed by pasteurized milk and cottage cheese. However, there was no significant difference between raw and pasteurized milk (p > 0.05). The mean AFM1 contamination in milk products ranged from 0.137 to 0.319 µg/L (mean value 0.285 µg/L). The contamination percentages of AFM1 in raw milk (62.50%), pasteurized milk (67.20%) and cottage cheese (25%) were above the regulatory limit set by the European Union (EU) (0.05 µg/L). According to USA/Ethiopian Standard (US/ES) (0.50 µg/L), 21.87%, 25% and 1% exceeded the regulatory limit for the above products, respectively. The overall prevalence (56.88%) was above the EU regulatory limit and 19.38% over US/ES regulations. Therefore, to provide accurate information about the health risk to consumers, there is a need to conduct risk assessment studies in consumers of milk and dairy products at different age groups.

Underreported Human Exposure to Mycotoxins: The Case of South Africa

“…Zebib, Abate [ 78 ] revealed that all milk samples collected among value chain actors were contaminated with AFM 1 . Aflatoxin M 1 is detectable within 12 h in milk after an animal consumes feed contaminated with AFB 1 [ 79 ].…”

“…The increasing consumption of animal products such as dairy, from different animal species, emphasises the need for carryover effect data from these animals as well, to ensure food safety. In Ethiopia, for example, all milk samples were reportedly contaminated with AFM 1 in varying concentrations [ 78 ]. There is a need to extend AF carryover surveillance to other mycotoxins and precursor compounds such as sterigmacystein and minor metabolites such as aflatoxicol.…”

“…Secondly, the scarcity of data on contamination with mycotoxins of foods that is commonly consumed in SA. Food items, such as milk and cheese, which are highly consumed in SA, are known to have high rates of contamination with AFM 1 elsewhere [ 78 ]. Unfortunately, SA might have few data on mycotoxin contamination in these products, as their rates of consumption data are unavailable.…”

Seasonal Occurrence of Aflatoxin M1 in Raw Milk during a Five-Year Period in Croatia: Dietary Exposure and Risk Assessment

“…Successive studies from Pakistan showed a significant incidence of raw milk contamination with AFM 1 in both summer (36%, 19%) and winter season (40%, 29%) [14,48]. Studies from countries whose climatic and geographical features contribute to the increased incidence of AFM 1 (> 50 ng/kg) in milk are Pakistan 53% [15], India 44% [49], Bangladesh 70% [50] and 23.8% [51], South Africa 81% [52], Ecuador 59.3% [53], and Ethiopia 62.5% [54]. The incidence of AFM 1 in milk in countries whose legislation prescribes an MRL of 500 ng/kg showed an incidence above 500 ng/kg were Brazil 38% [55], Pakistan 69% and 90.9% [56,57], and Ethiopia 21.9% [54].…”

Multiple Isothermal Amplification Coupled with CRISPR–Cas14a for the Naked-eye and Colorimetric Detection of Aflatoxin B1

“…5,6 The United States Food and Drug Administration has set the allowable detectable amount of AFB1 at 20 ppb (μg mL −1 ), and the European Union has established a maximum allowable detection limit of 6.4 nM for AFB1 in cereals and their products. 7,8 Therefore, there is an urgent need to develop a rapid, simple, and sensitive method for accurately quantifying AFB1 and warning against food contamination.…”