Short communication Determination of aflatoxin M1 in dairy cattle milk in Khartoum State, Sudan Amin O. Elzupir * , Abdelrahim M. Elhussein Central Laboratory – Ministry of Sciences & Technology, Khartoum, Sudan article info Article history: Received 18 September 2009 Received in revised form 3 November 2009 Accepted 24 November 2009 Keywords: Aflatoxin M1 Dairy cattle milk HPLC abstract Aflatoxins are a group of mycotoxins that contaminate various types of food and feedstuff leading to health risk in both humans and animals. Aflatoxin M1 (AfM1), the major metabolite of AfB1, was deter- mined in dairy cattle milk samples of Khartoum State of Sudan using high-performance liquid chroma- tography (HPLC) with fluorescence detection. A total of 44 bulk dairy cattle milk samples were collected and analyzed. The percentage of AfM1 contamination has been found in 42/44 (95.45%) samples with contamination level ranging between 0.22 and 6.90 lgL À1 and average concentration of 2.07 lgL À1 . AfM1 contamination in the samples of dairy cattle milk of Khartoum State of Sudan appears to be preva- lent and may pose a public health problem at the moment. Awareness must be conveyed to producers, handlers and specialists. Ó 2009 Elsevier Ltd. All rights reserved. 1. Introduction Aflatoxins are a large family of mutagenic, teratogenic and hepatocarcinogenic compounds produced as secondary metabolic products by certain strains of Aspergillus (A) flavus and A. parasiticus (Santacroce et al., 2008; Whitlow & Hagler, 2002) that, contami- nate peanuts, cereals, cottonseed, corn, rice and other commodities with widespread contamination in hot and humid regions of the world (Murphy, Hendrich, Landgren, & Bryant, 2006). AfM1 and AfM2 are the hydroxilated metabolites of aflatoxin B1 (AfB1) and B2 (AfB2) and may be found in milk products obtained from live- stock that have ingested contaminated feed (Unusan, 2006). AfB1 has been shown through research to be the most potent naturally occurring carcinogen in animals, with a very strong link to human cancer incidence (Richard, Glenn, ROSS, & Nelson, 1993; Verma, 2004) Although, AfM1, is less carcinogenic and mutagenic than AfB1, it exhibits a high level of genotoxic activity and certainly rep- resents a health risk because of its possible accumulation and link- age to DNA (Heshmati & Milani, 2010). The occurrence of AfM1 in milk is a public health concern so that AfM1 was classified by the International Agency of Research on Cancer as class 2B, possible human carcinogens (Boudra, Barnouin, Dragacci, & Morgavi, 2007). The USA Food and Drug Administration (FDA) has estab- lished 0.5 lgL À1 as an action level for aflatoxin present milk (Khanafari, Soudi, & Miraboulfathi, 2007). In a pervious study the prevalence of aflatoxins in animal feed in Khartoum State was investigated. The results showed high value of AfB1 contamination which was detected in (32.14%) of the sam- ples, with an average concentration of 109.68 lg/kg and concen- tration range of 5.94–327.73 lg/kg (Elzupir, Younis, Fadul, & Elhussein, 2009), this prompted us to carry out the present inves- tigation on aflatoxin contamination of dairy cattle milk which is the most commonly used milk in Khartoum State, Sudan. 2. Materials and methods 2.1. Sampling Forty four fluid bulk milk samples (1000 mL of volume) were collected from different dairy farms and vendors in Omdurman, Khartoum and Khartoum North during 2009. The samples were kept at À20 °C deep-freezer till tested. At the time of analysis sam- ples were brought up to room temperature (Richard et al., 1993). 2.2. Extraction of aflatoxin M1 Aflatoxin M1 was extracted using AOAC official method 980.21. In brief; 8 mL chloroform and 0.6 lL salt solution (10 g NaCl in 50 mL H 2 O) was added into 15 mL falcon tube containing 3 mL of milk, securely stoppered, shaked gently. The volume of chloroform extract was recorded, transferred into screw capped borosilicate vial and then evaporated to dryness. The extract was dissolved with 2 mL acetonitrile, defatted twice with 3 mL petroleum ether and evaporated to dryness (Jonsyn, Maxwell, & Hendrickse, 1995). The dry film was redissolved with 200 lL mobile phase (Methanol:water:acetic acid (65:35:1)) for HPLC analysis. 2.3. Separation and detection The HPLC chromatograph was used for AfM1 determination adopting fluorescence detection (Jonsyn et al., 1995) with excita- 0956-7135/$ - see front matter Ó 2009 Elsevier Ltd. All rights reserved. doi:10.1016/j.foodcont.2009.11.013 * Corresponding author. Tel.: +249 911355464. E-mail address: aminosman81@gmail.com (A.O. Elzupir). Food Control 21 (2010) 945–946 Contents lists available at ScienceDirect Food Control journal homepage: www.elsevier.com/locate/foodcont