Chickpea (Cicer arietinum L.), also called garbanzo bean or Bengal gram, belongs to the family Fabaceae of class dicots (Lev-Yadun et al. 2000). It is an important legume crop cultivated over an area of 963.0 hectares with a production of about 675.2 tons in Pakistan. It is the most nutritive pulse extensively used as protein addition to starchy diet. The major issue which influences the chickpea is naturally occurring aflatoxins (AFB1, AFB2, AFG1 and AFG2) with AFB1 the most important, toxic and carcinogenic. Aflatoxins (AFB1, AFB2, AFG1, and AfG2) are toxins produced by Aspergillus flavis and Aspergillus parasiticus infecting the agricultural crops. Chickpea is largely contaminated by aflatoxins in Pakistan due to seasonal variations, improper management of grains and contaminated soils. These are dangerous fungal metabolites that impair child development, suppress the immune system, cause cancer and in severe acute exposure death occurs, so it is necessary to estimate its toxicity in public health perspective.
For this purpose present study was conducted to determine the level of aflatoxins in Chickpea samples (Roasted and Unroasted). Samples were collected from different areas of Lahore i.e. Anarkali, Icchra, Model town, Gulberg, Mughalpura,Iqbal Town, Samnabad, Secretriate, Sabza Zar, Wahdat Road, Shad Bagh, Data Darbar, Thokar Niaz Begh, Cantt, Lohari Gate, Outfall Road, Dharampura, Joray Pull, Rehman Pura, Mozang, Faiz Bagh, Akbari Mandi, Liberty, Jallo Morh, Lahore Medical Society, Darogha Wala, Firdous Market, Siddiqia Colony, District Court, Sanat Nagar and also from chickpea vendors. The samples were analyzed by thin layer chromatography (TLC) to check the presence of aflatoxins (B1, B2, G1 & G2). TLC analyses were further confirmed by high performance liquid chromatography (HPLC) to verify the accuracy of TLC. These analyses were performed in the Department of Food Science and Human Nutrition and WTO labs, University of Veterinary and Animal Sciences, Lahore.
Experimental results showed that 60 out of 120 samples were contaminated with four different types of aflatoxins. In other words, 50% samples were found contaminated with aflatoxnis. Aflatoxin B1 was the major aflatoxin found in many samples but aflatoxins B2, G1 and G2 were also identified. Samples were analyzed on TLC method and 5% of contaminated samples were re- evaluated on HPLC technique to get precise results. Out of 120 samples sixty samples (50%) were collected from retail shops and other sixty (50%) samples were collected from street vendors. Each category of sixty samples holds 50% roasted and 50% un-roasted samples. Out of 120 total samples of chickpea 60 samples were taken from vendors with 2 categories of roasted and unroasted while 60 samples were collected from shops with the same categories. In those 120 samples, 60 (50%) were contaminated. From those 60 samples 39 (65%) samples were contaminated with aflatoxin B1. And it was also observed that the aflatoxin contamination level in vendors sample was high as compared to samples collected from shops. Out of 39 AFB1 contaminated samples vendor’s samples included 26 (66.66%) samples and samples collected from shops included 13 (33.3%) samples. In 26 vendors’ samples contaminated by AFB1, 18 (69.2%) samples were un-roasted while 8 (30.7%) samples were roasted. Aflatoxin B2 was present in 14 (23.33%) samples from these 60 contaminated samples, and presents only in both vendors and shops samples i.e. 7 (50%) samples from vendors and 7 (50%) from shops. From these AFB2 contaminated samples 10 samples (71.4%) were un-roasted and 4 samples (28.5%) was roasted. Aflatoxin G1 is also present in 5 samples (8.33%), out of which one sample (20%) was collected from vendors and 4 samples (80%) was collected from shop. From these G1 contaminated samples, 1 (20%) was roasted and 4 (80%) was un-roasted. Aflatoxin G2 is present only in two samples collected from vendors and shops, and we can say that 3.33% samples were contaminated with aflatoxin G12, out of 60 contaminated samples. From above results it is concluded that out of 60 contaminated samples 43 (71.66%) were un-roasted and 17 samples (28.33%) were roasted. After the aflatoxin determination in 60 shop’s and 60 vendor’s roasted and unroasted chickpea samples 5 samples were further processed at home by keeping 1 sample unroasted and 4 samples roasted at time intervals of 5mins,10mins,15mins and 20mins in sand bath. All the samples were free from the aflatoxin contamination except one which was unroasted. AFB1 was present in that sample at its minimum level i.e. 32.16µg/kg.
AFB1 was present more frequently in chickpea samples. Present study will be supportive for the investigation of aflatoxins in chickpea samples. Chickpea is widely consumed all over the world and occurrence of aflatoxins in this commodity is a major concern to human health. The present situation is too much worse about the levels of aflatoxins which are higher than the prescribed limit by the regulatory authorities. It was observed that TLC technique is good for the determination of aflatoxins in developing countries where the facilities of sensitive instruments are not accessible. Furthermore to quantify levels of aflatoxins by using sensitive instruments like HPLC, GC-MS and LC-MS is required for accurate detection of Aflatoxins (B1, B2, G1 & G2) in chickpea samples available in markets to protect the consumers from exposure of aflatoxins high level which are carcinogenic and hepatotoxic.