Dietary Exposure and Natural Occurrence of Total Aflatoxins in Basmati Rice of Pakistan

Comprehensive Review of Aflatoxin Contamination, Impact on Health and Food Security, and Management Strategies in Pakistan

Aflatoxins (AFs) are the most important toxic, mutagenic, and carcinogenic fungal toxins that routinely contaminate food and feed. While more than 20 AFs have been identified to date, aflatoxin B1 (AFB1), B2 (AFB2), G1 (AFG1), G2 (AFG2), and M1 (AFM1) are the most common. Over 25 species of Aspergillus have been shown to produce AFs, with Aspergillus flavus, Aspergillus parasiticus, and Aspergillus nomius being the most important and well-known AF-producing fungi. These ubiquitous molds can propagate on agricultural commodities to produce AFs in fields and during harvesting, processing, transportation, and storage. Countries with warmer climates and that produce foods susceptible to AF contamination shoulder a substantial portion of the global AF burden. Pakistan's warm climate promotes the growth of toxigenic fungi, resulting in frequent AF contamination of human foods and animal feeds. The potential for contamination in Pakistan is exacerbated by improper storage conditions and a lack of regulatory limits and enforcement mechanisms. High levels of AFs in common commodities produced in Pakistan are a major food safety problem, posing serious health risks to the population. Furthermore, aflatoxin contamination contributes to economic losses by limiting exports of these commodities. In this review, recent information regarding the fungal producers of AFs, prevalence of AF contamination of foods and feed, current regulations, and AF prevention and removal strategies are summarized, with a major focus on Pakistan.

Exposure to multiple mycotoxins in domestic and imported rice commercially traded in Tehran and possible risk to public health

Mycotoxins are secondary fungi metabolites that induce acute and chronic toxic effects in humans and animals. In the present study, nine mycotoxins including aflatoxins (AFB1, AFB2, AFG1 and AFG2), fumonisins (FB1 and FB2), Ochratoxin A (OTA), deoxynivalenol (DON), and zearalenone (ZEN) were determined in one hundred rice samples collected from Tehran using high performance liquid chromatography (HPLC) with fluorescence or photodiode array detector. In addition, possible risk to public health was investigated by assessing dietary exposure through rice consumption, the margin of exposure (MOE), respective risk of cancer and hazard index (HI) of the monitored mycotoxins in children and adults. The higher mean levels were determined for DON (102.22 μg.Kg-1), followed by FB1 (85.00 μg.Kg-1). For the rests of mycotoxins the levels did not exceed 20 μg.Kg-1. The estimated AFB1 intake for the adults and children through rice consumption exceeds the safe levels established for both carriers and non-carriers of hepatitis B virus. The mean and median determined exposure levels of OTA, DON ZEN and FB1, were found lower than the Provisional Maximum Tolerable Daily Intake (PMTDI) value for both adults and children of Tehran that consuming domestic and imported rice. The mean HI for adults and median HI for adults and children were below one, and mean HI for children was close to one. All the mean, median and maximum MoE values were <10,000 in adults and children, indicating a risk due to AFB1 exposure through rice consumption in Tehran. In addition, the calculated mean cancer risk in adult and child populations of Tehran were 0.27 and 0.64 cases per year per 105 individuals, respectively, that shows population in Tehran could be at risk of cancer due to AFB1 exposure through rice consumption as calculated. So further studies are necessary for the monitoring mycotoxins in rice and different food products as well as estimating average dietary exposure and cumulative exposure assessment of mycotoxins for main foods in IR Iran.

Concentration and Prevalence of Aflatoxin M1 in Human Breast Milk in Iran: Systematic Review, Meta-Analysis, and Carcinogenic Risk Assessment: A Review

This meta-analysis was designed to review the published reports regarding the concentration and/or prevalence of aflatoxin M₁ (AFM₁) in human breast milk in Iran. The carcinogenic risk for Iranian infants consuming this milk was estimated with the hazard index. The PubMed and Scopus databases and the Scientific Information Database were screened for relevant studies between 1995 and 2017, and 11 of the 112 collected studies were included in the systematic review and meta-analysis. The mean (95% confidence interval) concentration of AFM₁ was 5.85 ng/L (4.54 to 7.15 ng/L), which was lower than the European Union standard (25 ng/L). The mean prevalence of AFM₁ in breast milk in Iran was 42% (11 to 77%). The estimated daily intakes for male and female infants were 0.02 to 5.57 ng/kg and 0.02 to 3.68 ng/kg of body weight per day, respectively. The rank order of estimated daily intake for both male and female infants according to age was 1 week > 1 month > 6 months > 12 months. The hazard index for all age groups of infants in all provinces in Iran was less than 1. Therefore, infants in Iran were not considered at carcinogenic risk from AFM₁ in human breast milk.

Multiple Mycotoxins in Rice: Occurrence and Health Risk Assessment in Children and Adults of Punjab, Pakistan

Mycotoxin contamination in rice can create a health risk for the consumers. In this study, the measurement of 23 mycotoxins in rice samples (n = 180) was performed using a validated LC–MS/MS method. A food frequency questionnaire was used to get rice consumption data for the assessment of mycotoxin dietary exposure, before calculating the health risk in adults and children of north and south regions of the Pakistani Punjab province. The prevalence of aflatoxin B₁ (56%), aflatoxin B₂ (48%), nivalenol (28%), diacetoxyscirpenol (23%), fumonisin B₁ (42%), zearalenone (15%), HT-2 toxin (10%), deoxynivalenol (8%), and ochratoxin A (6%) was estimated in samples with a mean concentration range between 0.61 and 22.98 µg/kg. Aflatoxin degradation by traditional Pakistani cooking recipes was evaluated and observed to be 41–63%. The dietary exposure to aflatoxins exceeded the tolerable daily intake at all levels, and ochratoxin A and zearalenone posed health risk at high contamination and high consumption levels. The margin of aflatoxin B₁ exposure ranged between 10 and 69 in adults and 10 and 62 in children. The mean cancer risk by aflatoxin B₁ exposure was 0.070 (adults) and 0.071 (children) cases/year/100,000 people in South Punjab population, and 0.122 (adults) and 0.127 (children) cases/year/100,000 people in North Punjab population. This study will provide new insights for the planning and management of mycotoxins in Pakistan.