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Title:	Dietary intake of aflatoxin in the adult Malaysian population - a risk assessmen
Authors:	Chin Cheow Keat (P42602)
Supervisor:	Aminah Abdullah, Prof. Dr.
Keywords:	Dietary Aflatoxin Adult Malaysian population Risk Diet -- Malaysia
Issue Date:	11-Aug-2012
Description:	This study estimates the dietary intake of aflatoxins and their association with liver cancer risk amongst adult Malaysian population aged 18 to 59 years. Based on the data from the Malaysian Food Consumption Survey in 2003, 38 foods (19 national foods and 19 regional foods) were selected for the purpose of sampling based on bibliographical knowledge on the occurrence of aflatoxins in raw and processed foods. National foods are foods processed by a small number of manufacturers and distributed throughout Malaysia. As national foods were not expected to show regional variation in contamination level, sampling was done in only one location from one region only. While regional foods were sampled in all regions in Malaysia as these foods may potentially vary in their contamination levels. From a total of 1196 food samples collected, 236 individual food composites were then prepared as "ready for consumption" and subsequently analysed for aflatoxins. The mean levels of aflatoxin B1 (AFB1) and total aflatoxins (AFT) were calculated for each food composite. Adopting a deterministic approach, estimates of dietary exposure were obtained by combining food consumption data with the mean concentration of AFB1 and AFT. Using all occurrence data, dietary exposure to AFB1 from this study ranged between 24.37 and 34.00 ng/kg b.w. per day (lower to upper bound), with peanuts being the main contributor. Using AFB1 liver cancer potency rate derived by Joint WHO/FAO Expert Committee on Food Additives and Malaysia's hepatitis B carrier rate of 5.24%, the exposure yielded an estimated liver cancer risk of 0.61- 0.85 cancer/year/100,000 population, which constituted 12.4 – 17.3% of the annual liver cancer cases in Malaysia. The impact of enforcing current maximum limit (ML) on exposure and risk were also estimated by excluding occurrence data above 15 and 5 μg/kg. Removing samples exceeding 15 μg/kg for AFB1 reduced the exposure by 65- 91% to 2.27 and 11.99 ng/kg b.w. per day (lower to upper bound). This correspondingly reduced the liver cancer risk to 0.06 – 0.30 cancers/year/100,000 population, which accounted for 1.2-6.1% of all liver cancer cases in Malaysia or a reduction of about 55 cancer cases/year/10 million pop (65-91% reduction). While reducing the ML further from 15 to 5 μg/kg yielded only a further 3-7% drop in exposure to 0.47 - 10.26 ng/kg b.w. per day and a 5-7% reduction in the estimated population risk from 0.06-0.3 to 0.01–0.26 cancers/year/100,000 population or a reduction in approximately 4-5 additional cancers/year/10 million population; thus lowering the number of liver cancer cases attributable to dietary AFB1 in Malaysia to only 0.2 – 5.1 %. For high consumers of peanuts, the exposure and corresponding liver cancer risk is approximately five times higher than those of the normal adult population. Between the different sexes, male has the higher estimated exposure and cancer risk. While amongst the ethnic groups, orang asli (indigenous people) has the highest exposure but in terms of cancer risk the ethnic Chinese has the highest risk. The findings indicated that current ML is adequate in protecting the health of Malaysian provided surveillance system is able to identify and remove contravening foods from the market, especially major foods contributing to exposure as it has the greatest risk on the population.,Ph.D
Pages:	259
Call Number:	TX360.M4.C484 2012
Publisher:	UKM, Bangi
Appears in Collections:	Faculty of Science and Technology / Fakulti Sains dan Teknologi

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