Mean Aflatoxin Levels Research Articles

Evaluation of aflatoxin content in “Cheka” (traditional beverage in South-Western Ethiopia) and its major ingredient (maize)

BackgroundAflatoxin is a toxic cancerous fungal secondary metabolite produced by Aspergillus species. Consumption of aflatoxin-contaminated cereals and their products can cause several health-related effects including acute and chronic aflatoxicosis. This study aims to evaluate the total aflatoxin content in “Cheka” and its major ingredients using the Immuno-Affinity Column Clean-up technique by sensitive HPLC (High-Performance Liquid Chromatography) with fluorescence detection.MethodsThis study followed a completely randomized experimental design to evaluate the level of aflatoxin in traditionally brewed “Cheka” and its major ingredients (maize) by HPLC from November 2019 to June 2020. Traditionally brewed 6 “Cheka” beverages and 6 maize seed samples were collected randomly from Konso and transported to Bless Agri Food Laboratory in Addis Ababa for laboratory evaluation of aflatoxin in samples. The data were analyzed by SPSS version 25.ResultsIn the present study aflatoxin contamination was detected in all maize and “Cheka” samples. A mean total aflatoxin level of 6.78 ± 8.28 μg/kg and 10.76 ± 4.50 μg/kg were observed in maize and “Cheka” samples respectively. The maize taken from above-ground storage (“Gotera”) and underground storage (pitfall) showed a mean total aflatoxin level of 10.23 ± 10.12 μg/kg and 3.35 ± 5.79 μg/kg respectively. The samples taken from “Cheka” prepared from maize of above-ground storage (“Gotera”) and underground storage (pitfall) showed a mean total aflatoxin level of 11.34 ± 3.06 μg/kg and 10.19 ± 6.35 μg/kg respectively. Aflatoxin G family was not detected in both maize and “Cheka” samples while aflatoxin B1 and B2 contributed to the total aflatoxin level. AFB1 predominantly contributed to the contamination of all samples. Although there was no significant difference while comparing between mean total aflatoxin of any other sample types, a significant difference was observed for the AFB1 mean level of pitfall maize and their respective “Cheka” samples (P = 0.033).ConclusionThe mean level of AFB1 in pitfall maize differs from a respective “Cheka” sample. As most of the samples evaluated for aflatoxin contamination showed levels above healthy cut-off points of aflatoxin set by different authorities like the European Union, CODEX, and Ethiopian Standards Agency, there must be a protracted interventional approach to reduce aflatoxin contamination in maize and its products in the region.

Evaluation of the Level of Aflatoxins in Raw Peanuts and Reduction Levels of Aflatoxins in Peanuts through Nixtamalization (Lime Treatment) and Calcium Enrichment

Nixtamalization has been widely used as a method of reducing aflatoxin contamination in peanuts as well as in calcium enrichment. The aim of this study is to investigate the effects of nixtamalization on aflatoxin and nutrient content in peanuts among wholesalers and retailers at Nyamakima Market in Nairobi, Kenya. A representative sample was drawn from a population of 70 market vendors using a systematic random sampling technique, resulting in 35 raw peanut samples for analysis via ELISA to determine initial aflatoxin levels. These samples were then subjected to nixtamalization treatments of 4, 8, and 16 minutes. The findings revealed that the average concentration of total aflatoxins in peanuts initially exceeded the accepted safety limit, with 71% of the samples failing to meet the standards. However, nixtamalization led to a substantial reduction in aflatoxin levels by 49%, 48%, and 50% after treatment durations of 4, 8, and 16 minutes, respectively. Statistical analysis, including ANOVA and Two-sample T-tests, confirmed significant distinctions between initial and final mean aflatoxin levels post-treatment, as well as variations between treatments. The study also observed a significant variation in calcium levels between the different time treatments, supported by linear regression analysis, which demonstrated a robust correlation between time treatments and calcium levels (R2=0.83, P=0.011). Furthermore, the analysis revealed significant differences in mean moisture contents across various treatments (P=0.000), and a linear relationship between mean moisture content and exposure time (P=0.02). The results emphasize the positive impact of nixtamalization in reducing aflatoxin levels and enhancing calcium content in peanuts. However, it is crucial to note the negative effect on moisture content, which exceeded stipulated limits, potentially raising concerns about product safety and quality.

Levels of total aflatoxins in maize and groundnuts across food value chains, gender and Agro-ecological zones of Uganda

Maize and groundnuts are traditional nutrient-rich and high economic value foods grown in Uganda. However, these crops are susceptible to aflatoxin contamination which may result into aflatoxicosis related illnesses. Occurrence of flatoxins in the foods varies across food value chains, gender and agro-ecological zones of Uganda. Therefore, we conducted a cross-sectional study in 80 maize and groundnut foodstuff from Masindi and Soroti agro-ecological districts respectively. We determined levels of total aflatoxins in maize and groundnut samples across food value chains, gender and agro-ecological zones. This was aimed at assessing safety and quality status of the foods in Uganda. Questionnaires were administered to obtain information on food handling practices. 500g of each food sample were obtained and analyzed for total aflatoxin levels using ELISA assay. Data was analyzed using descriptive and analytical statistics. In overall, 45% of maize and 30% of groundnut foods were contaminated with aflatoxins. Mean aflatoxin levels in foods from Eastern and Western agro-ecological zones were 0.052±0.036ppb and 0.045±0.033ppb respectively (p=0.124). Mean aflatoxin levels in groundnuts from both male and female respondents were coincidentally 0.052ppb. Whereas, the mean aflatoxin levels in maize from male and female respondents were 0.056±0.037ppb and 0.039±0.029ppb respectively. Across the food value chain, wholesaler groundnut foods contained the highest mean aflatoxin levels of 0.088ppb (p= 0.27). Growing high polyamine containing crops, routine testing of aflatoxin prone foods and sensitizing food value chain players are important aflatoxin control strategies.

Occurrence of aflatoxins in nuts and peanut butter imported to UAE

Nuts are an important food group that contributes to maintaining health; however, they can be a source of exposure to aflatoxins. This study was conducted from 2017 to 2021 to assess the incidence of aflatoxins in nuts and nut products imported to the UAE from 57 countries. Associations between container type and processing technique and aflatoxin levels were also analyzed. A total of 5401 samples of pistachios, peanuts, peanut butter, and mixed nuts were examined using HPLC-FLD analysis in conjunction with immunoaffinity cleanup. In nuts, non-conformity was detected in samples imported from 32 different countries. Mean aflatoxin values for the non-compliant samples ranged from 81.0 to 92.7 μg/kg in pistachios, peanuts, and mixed nuts. A significant difference (p < 0.05) was found between mean aflatoxin levels in samples of peanut butter (29.3 μg/kg) compared to the other types of nuts. Nuts packed in containers made of fabric material had the highest mean aflatoxin levels of 108.1 μg/kg, while 29.7 μg/kg was the lowest mean level and was detected in nuts packed in glass. Ground samples had the highest aflatoxin levels (158.9 μg/kg) among processed products. This report will be valuable as a reference document in developing approaches to control nut importation and for establishing procedures that prevent food safety risks due to aflatoxin exposure. A need was underlined for the regulating authority to audit companies importing nuts, ensure safe practices are in place, and establish standards to minimize contamination and prevent the need for product rejection at the border.

Aflatoxin Susceptible Food Consumption Frequency, Prevalence, and Levels in Household Foodstuffs in Southwestern Uganda

Contamination of household foodstuffs by aflatoxins has been associated with many illnesses, especially hepatocellular cancer and malnutrition. Aflatoxins are toxins produced by fungi, especially Aspergillus flavus and Aspergillus parasiticus, usually found in food. Literature concerning the S.W. Ugandan foods that are the main aflatoxicosis route and therefore need most aflatoxin preventive measure is scanty. The current study determined the aflatoxin-susceptible food consumption frequency, prevalence, and levels of aflatoxins in selected foodstuffs in households in S.W. Uganda to establish the main food route of aflatoxicosis. Following a food frequency questionnaire, flour samples of common foodstuffs, namely, groundnuts, maize, millet, and sorghum, were randomly picked from seven districts of Southwest Uganda and analyzed for the presence and levels of aflatoxins using competitive ELISA. On average, maize and groundnut were found to be the most frequently consumed foods (seven times a week) by every family. Groundnuts had the highest mean aflatoxin level (96.5 ± 13.37 μg/kg), ranging from 6.2 to 297.3 μg/kg. Over 90% of the groundnut samples had mean aflatoxin levels greater than 10 μg/kg, the East African regulatory limit. Maize flour had a mean aflatoxin level of 34.1 ± 14.1 μg/kg, with one sample registering 336.5 μg/kg. This study found that groundnuts were the main food-route for aflatoxicosis followed by maize flour. In addition, the study re-affirmed the high prevalence and levels of aflatoxins in common food stuff in households in S.W. Uganda reported by previous studies. This study recommends further studies to elucidate its association with the observed recent increase in diseases like hepatocellular cancer and malnutrition in the region.

Verification of the Accuscan gold reader and RIDA smart phone application rapid test kits in detection and quantification of aflatoxin levels in maize from selected regions in Kenya

The study aimed to verify the effectiveness of two detection kits namely, Accuscan gold reader and RIDA total aflatoxin smart phone application in assessing levels of aflatoxins’ contamination in maize. Three regions of Kenya were selected namely, Kisumu, Makueni and Kilifi. Confirmatory tests were done using liquid chromatography tandem mass spectrometry (LC-MS/MS). The Accuscan gold reader showed mean aflatoxin levels of 14.52, 5.18, and 3.04 μg/kg and RIDA smart phone application had levels of 26.08, 26.68, and 4.05 μg/kg for Kilifi, Makueni, and Kisumu, respectively. The LC-MS/MS confirmed the presence of AFB1 and AFB2 with AFB1 of 97.5 μg/kg in Makueni and 76.2 μg/kg in Kilifi. Maize from Kilifi and Makueni was contaminated and unfit for human and animal consumption. Also, low rainfall, high temperature and high relative humidity directly increased the levels of aflatoxins, resulting in contamination. Therefore, the detection kits are recommended for use by maize farmers. Confirmatory tests should be done with maize having levels of aflatoxin above 10 μg/kg. Adequate drying and handling of maize and proper storage with good aeration should be ensured.

Aflatoxin contamination in Tanzania: quantifying the problem in maize and groundnuts from rural households

Aflatoxins are toxic and carcinogenic secondary metabolites, produced byAspergillus flavus andAspergillus parasiticus, which contaminate food and feed and threaten human and animal health. To assess the prevalence of aflatoxins in Tanzania, 180 groundnut and 200 maize samples were collected from 9 and 10 districts, respectively. Aflatoxin contamination was quantified using high performance liquid chromatography. Aflatoxins were detected in samples collected from all districts and prevalence ranged from 92 to 100% for groundnuts and 10 to 80% for maize. The mean aflatoxin level for groundnuts was 6.37 μg/kg and the highly contaminated sample had 40.31 μg/kg. For maize, the mean aflatoxin level was 12.47 μg/kg and the highly contaminated sample had 162.40 μg/kg. The estimated average probable daily intake (APDI) of aflatoxin B1 (AFB1) from groundnuts consumption was 1.88 ng/kg body weight/day, while for maize, it ranged between 151.98-272.89 ng/kg body weight/day. The APDI for both groundnut and maize exceeded the provisional maximum tolerable daily intake (PMTDI) of AFB1 for adults (1 ng/kg body weight/day), bringing about health concerns for populations in Tanzania. Another alarming finding was that 75% of the farmers who provided samples for analysis were not aware of aflatoxins or the negative health impacts from consuming contaminated products. Results reported in this paper show that aflatoxin contaminated staple crops are widely distributed in Tanzania and that the risk of human exposure is high due to diet preferences. Awareness campaigns are required to inform and protect farmers and consumers.

Effects of the Use of Good Agricultural Practices on Aflatoxin Levels in Maize Grown in Nandi County, Kenya

Aflatoxin contaminated maize is of public health concern in Kenya. Training farmers on good agricultural practice (GAP) has been touted as a mitigative measure. Little is known of the effect of such training on aflatoxin levels in maize grown in Kenya. This study evaluated what effect training farmers on GAP has on aflatoxin levels in maize grown in Kaptumo, Kilibwoni, and Kipkaren divisions in Nandi County. Ninety farmers were recruited for the study and interviewed on GAP. Maize samples were additionally collected from the participating farmers and analyzed for aflatoxins using competitive enzyme-linked immunosorbent assay (c-ELISA). All farmers prepared the land before planting, applied correct spacing between the planted crops, carried out weeding, cleaned their stores before use, checked the condition of the maize after harvesting, sorted maize after shelling, and knew about aflatoxins. The majority of the farmers (90%) used fertilizers, dried maize after harvesting, knew that aflatoxins were harmful to humans, and used clean transport in transporting the harvested maize. About 98% of farmers did stooking after harvesting and 97% used wooden pallets in the maize stores. The percentage of farmers who practiced early planting, top dressing, crop rotation, raising stores above the ground, applying insecticide after shelling and feeding damaged/rotten seeds to their animals was 84–96%, 62–80%, 67–85%, 86–98%, 63–81%, and 7–21% respectively. About 18/90 (20%) of all farmers reported that they had a relative who had died from liver cancer, and the mean aflatoxin levels in season 1 were significantly different from those in season 2 (1.92 ± 1.07 ppb; 1.30 ± 1.50 ppb). Our findings suggest that although training farmers to adopt good agricultural practices was observed to be efficient in mitigating the problem of aflatoxins, the receptiveness of farmers to different aspects of the training may have differed. Therefore, in designing an optimized regional aflatoxin contamination strategy, local applicability should be considered.

On-farm evaluation of effectiveness of improved postharvest handling of maize in reducing grain losses, mold infection and aflatoxin contamination in rural Uganda

Postharvest losses remain a challenge among smallholder farmers in sub-Saharan Africa. The uses of hermetic storage containers (hermetic bags and metallic silos), tarpaulin sheet (plastic sheet) and raised racks reduce postharvest deterioration of grain. This study evaluated the effectiveness of selected improved drying and storage postharvest technologies and practices in reducing maize grain postharvest losses among smallholder farmers in Kamuli and Apac districts, Uganda. The assessed improved storage technologies were hermetic bags and metallic silos against woven polypropylene bags (common farmer practice). For drying, use of tarpaulins and raised racks were assessed against drying on bare ground (common farmer practice). Grain quality and quantity were determined at harvest as well as during drying and six months of storage using Longe 10H variety. Mean quantitative losses, mold infection and aflatoxin level of maize at harvest were 13.72 ± 5.44%, 59.01 ± 17.97% and 1.21 ± 0.7 ppb, respectively for traditional practice. Improved drying and storage technologies resulted in significantly lower (p≤0.05) losses, mold infection and aflatoxin level than the common farmer practices. Drying on bare ground (3.04 ± 1.50%) resulted in 1.94 times and 7.07 times higher quantitative losses than drying on tarpaulins (1.56 ± 1.09%) and raised racks (0.43 ± 0.58%). By the sixth month of storage, polypropylene bag storage resulted in 3.7 times and 84 times higher quantitative losses (23.7 ± 5.11%) than hermetic bags (6.33 ± 5.41%) and metallic silos (0.28 ± 0.22%), respectively. Polypropylene bag storage also resulted in 4.4 times and 6 times higher aflatoxin levels (45.82 ± 20.88 ppb) than hermetic bags and metallic silos, respectively. The interaction effects of type of drying technology and storage technology used on aflatoxin levels at the end of the storage period was significant. The highest mold infection and aflatoxin levels were observed when drying was done on bare ground and storage was in polypropylene bags and by the sixth month of storage, mold infection was 90.54 ± 5.48% and average aflatoxin content was 53.47 ± 22.79 ppb. Storage in metallic silos was the most effective in controlling mold infection and aflatoxin contamination, regardless of drying practice, while storage in polypropylene bags was the least effective. From the results, improved drying and storage technologies and practices were found to reduce postharvest maize losses, mold infection and aflatoxin level by over 50%. Use of raised drying racks and storage in metallic silos was found to be the most effective combination in maintaining maizequality and reducing postharvest losses. Key words: Aflatoxins, maize quality, mold infection, grain storage, postharvest losses

Fungi and Aflatoxin Levels in Traditionally Processed Cassava (Manihot esculenta Crantz) Products in Homa Bay County, Kenya.

Cassava (Manihot esculenta Crantz) is a major source of carbohydrates, calcium, vitamins (B and C), and essential minerals and is the third most important source of calories in the tropics. However, it is not clear if the traditional processing methods expose the products to microbial contamination. This study assessed the levels of fungi and aflatoxin contamination in traditionally processed cassava products (Akuoga and Abeta). A total of 38 samples were collected from the local markets in 7 subcounties in Homa Bay County, Kenya. The levels of aflatoxin were determined using an indirect competitive ELISA protocol. Yeast and mould contamination was determined using ISO 21527-2 method. Mean aflatoxin levels in chopped, fermented, and sun-dried cassava (Akuoga) were 0.36 μg/kg compared to 0.25 μg/kg in chopped and sun-dried (Abeta) products. Aflatoxin contamination was detected in 55% of the samples and ranged from 0–5.33 μg/kg. These levels are within 10 μg/kg recommended by the CODEX STAN 193-1995. Yeast and mould counts in fermented and chopped sun-dried products were 3.16 log Cfu/g and 2.92 log Cfu/g, respectively. The yeast and mould counts were above standards set by East African Standard 739:2010 in 62% (Akuoga) and 58% (Abeta). The most prevalent fungal species were Saccharomyces cerevisiae (68.4%) and Candida rugosa (68%) followed by Candida parapsilosis (18.4%), Candida tropicalis (15.8%), Candida humilis (15.8%), and Aspergillus spp. (5.3%). Aspergillus spp. was the only mycotoxigenic mould isolated from the samples. The study shows that cassava consumers are exposed to the risk of aflatoxin poisoning. The study, therefore, recommends appropriate surveillance to ensure safety standards.

Effects of the Use of Good Agricultural Practices on Aflatoxin Levels in Maize Grown in Nandi County, Kenya

Aflatoxin contaminated maize is of public health concern in Kenya. Training farmers on good agricultural practice (GAP) has been touted as a mitigative measure. Little is known of the effect of such training on aflatoxin levels in maize grown in Kenya. This study evaluated what effect training farmers on GAP has on aflatoxin levels in maize grown in in maize grown in Kaptumo, Kilibwoni, and Kipkaren divisions in Nandi County. Ninety farmers were recruited for the study and interviewed on GAP. Maize samples were additionally collected from the participating farmers and analyzed for aflatoxins using competitive enzyme-linked immunosorbent assay (c-ELISA). All farmers prepared the land before planting, did correct spacing between the planted crops, carried out weeding, cleaned their stores before use, checked the condition of the maize after harvesting, sorted maize after shelling, and knew aflatoxins. A majority of the farmers (90%) used fertilizers, dried maize after harvesting, knew that aflatoxins were harmful to humans, and used clean transport in transporting the harvested maize. About 98% of farmers did stooking after harvesting and 97% used wooden pallets in the maize stores. The percentage of farmers who practiced early planting, top dressing, crop rotation, raising stores above the ground, applying insecticide after shelling and feeding damaged/rotten seeds to their animals was 84–96%, 62–80%, 67–85%, 86–98%, 63–81%, and 7–21% respectively. About 18/90 (20%) of all farmers reported that they had a relative who had died from liver cancer and the mean aflatoxin levels in season 1 were significantly different from season 2 (1.92 ± 1.07 ppb; 1.30 ± 1.50 ppb). Our findings suggest that although training farmers to adopt good agricultural practices was observed to be efficient in mitigating the problem of aflatoxins, the receptiveness of farmers to different aspects of the training may have differed. Therefore, in designing an optimized regional aflatoxin contamination strategy, local applicability should be considered.

Aflatoxin Contamination of Milk Produced in Peri-urban Farms of Pakistan: Prevalence and Contributory Factors.

Aflatoxin M1 contamination of milk in Pakistan, like many developing countries, is poorly understood. The present study was therefore conducted to determine AFM1 contamination of milk and its contributory factors in Pakistan. We sampled milk and feedstuffs from 450 peri-urban dairy farms in seven major cities following a cross-sectional study design. Analysis of milk using ELISA revealed high contamination with an overall average of 3164.5 ng of AFM1/L, and significant differences (p < 0.001) between cities. The milk sampled from Gilgit, in northern hilly areas, had an average AFM1 level of 92.5 ng/L. Milk from other cities had 3529.7 ng/L average contamination, with only 5.7% samples qualifying the maximum tolerable limit of 500 ng of AFM1/L. Heavy mean aflatoxin contamination was found in bakery waste (724.6 μg/kg), and cottonseed cake (600.8 μg/kg). Rest of the other feedstuffs had moderate to low mean aflatoxin contamination, ranging from 66.0 μg/kg in maize stover to 3.4 μg/kg in wheat bran. The mean aflatoxin level in commercial dairy concentrates was 32.7 µg/kg. About 80% of the total aflatoxin intake of dairy animals was contributed by cottonseed cake alone due to its high aflatoxin contamination and proportion in dairy rations. On-farm storage time of oilseed cakes varied (p < 0.01) in different cities but was not associated with aflatoxin contamination. The exceptionally high AFM1 contamination suggests that milk from peri-urban dairy farms is a serious public health threat in Pakistan. This situation can be mitigated by reducing aflatoxin contamination in cottonseed cake and promoting the use of commercial concentrates and other feedstuffs with low contamination.

Assessment of Aflatoxin and Fumonisin Contamination and Associated Risk Factors in Feed and Feed Ingredients in Rwanda.

Mycotoxins are fungal metabolites that contaminate crops, food, and animal feeds. Aflatoxins and fumonisins are among the mycotoxins that have been increasingly reported to affect health and productivity of livestock globally. Given that the health and productivity of livestock can directly influence human food safety and security, a study was conducted to assess the levels and factors for aflatoxin and fumonisin contamination in feed and feed ingredients in Rwanda. Aflatoxins and fumonisins were analyzed in 3328 feed and feed ingredient samples collected at six time points between March and October 2017 in all 30 districts of Rwanda. Of the 612 participants providing samples, there were 10 feed processors, 68 feed vendors, 225 dairy farmers, and 309 poultry farmers. Enzyme-Linked Immunosorbent Assay (ELISA) was used for aflatoxin and fumonisin analyses. Mean aflatoxin levels of 108.83 µg/kg (Median (MD): 43.65 µg/kg), 103.81µg/kg (MD: 48.4 µg/kg), 88.64 µg/kg (MD: 30.90 µg/kg), and 94.95 µg/kg (MD: 70.45 µg/kg) were determined for dairy farmers, poultry farmers, feed vendors, and feed processors, respectively. Mean fumonisin levels were 1.52 mg/kg (MD: 0.71 mg/kg), 1.21 mg/kg (MD: 0.56 mg/kg), 1.48 mg/kg (MD: 0.76 mg/kg), and 1.03 mg/kg (MD: 0.47 mg/kg) for dairy farmers, poultry farmers, feed vendors, and feed processors, respectively. Aflatoxin contamination was significantly affected by time of sampling and district from which feed samples originated (p < 0.05). Fumonisins did not show any correlation trends. Ninety-two percent of survey participants were unaware of aflatoxins and fumonisins and their adverse effects. This study has provided the basic understanding of the extent of feed contamination across the country and has established a baseline for future interventions in Rwanda. Further studies are needed to explore strategies for mitigating mycotoxins in the feed value chain in Rwanda.

Effects of the Use of Good Agricultural Practices on Aflatoxin Levels in Maize Grown in Nandi County, Kenya

Aflatoxin contaminated maize is of public health concern in Kenya. Training farmers on good agricultural practice (GAP) has been touted as a mitigative measure. Little is known of the effect of such training on aflatoxin levels in maize grown in Kenya. This study evaluated what effect training farmers on GAP has on aflatoxin levels in maize grown in Kaptumo, Kilibwoni, and Kipkaren divisions in Nandi County, Kenya. Ninety farmers were recruited into farmer field schools and a questionnaire on GAP administered to each farmer. Maize samples were collected from the farmers and analyzed for aflatoxins using competitive enzyme-linked immunosorbent assay (c-ELISA). All farmers weeded their farms before planting, prepared the land, correctly spaced the seedlings, sorted the maize after shelling, cleaned stores before use and knew that aflatoxins were harmful to humans and animals. Eighty-one farmers did early planting, 88/90 did stooking after harvesting, 89/90 applied fertilizer, 89/90 cleared bushes around the stores, 87/90 used wooden pallets to store maize, 89/90 dried maize after harvesting, 83/90 did crop rotation, and 89/90 used clean transport. Moreover, 62/90 had a relative who had died from liver cancer, 13/90 had fed damaged/rotten seeds to animals, and 45/90 had stored harvested seeds on the ground. The mean aflatoxin levels in season 1 were significantly different from season 2 (1.918 ± 1.065; 1.301 ± 1.501). Our findings suggest that some aspects of the training on GAP were better received than others. Training farmers on GAP results in a decrease in aflatoxin levels in maize grown in Nandi County. Farmers in other maize growing areas of Kenya may benefit from similar training on GAP.

Status of aflatoxin contamination in cow milk produced in smallholder dairy farms in urban and peri-urban areas of Nairobi County: a case study of Kasarani sub county, Kenya

ABSTRACTIntroduction: Milk consumption in Kenya supersedes other countries in East Africa. However, milk contamination with aflatoxin M1 (AFM1) is common, but the magnitude of this exposure and the health risks are poorly understood and need to be monitored routinely. This study aimed at assessing the awareness, knowledge and practices of urban and peri-urban farmers about aflatoxins and determining the levels of aflatoxin contamination in on-farm milk in a selected area within Nairobi County.Materials and methods: A cross-sectional study was undertaken to assess aflatoxin contamination levels of milk in Kasarani sub-county. A total of 84 milk samples were collected from small-holder dairy farms and analyzed for AFM1 using Enzyme-Linked Immunosorbent Assay (ELISA).Results and Discussion: Ninety nine percent of the samples (83/84) analysed were contaminated with AFM1. The mean aflatoxin level was 84 ng/kg with 64% of the samples exceeding the EU legal limit of 50 ng/kg. Whereas 80% of the farmers were aware of aflatoxin, there was no correlation between farmers’ knowledge and gender with AFM1 prevalence.Conclusion: This study concludes that AFM1 is a frequent contaminant in milk and there is need to enhance farmers awareness on mitigation.

Moisture content, insect pest infestation and mycotoxin levels of maize in markets in the northern region of Ghana

Reliable quantitative data on maize post-harvest losses and factors that cause them in northern Ghana are limited. In this study we assessed maize at six markets in the Northern Region of Ghana, in and around Tamale, during the harvest and storage period of October 2015–June 2016. Across all the markets and sampling periods grain temperature was 32.6 ± 0.2 °C and equilibrium moisture content (EMC) was 9.5 ± 0.2%. EMC tended to decrease to a low in January and February and then increased again, while mean maize temperature was above 30 °C in all months. The primary stored product insects collected from the samples were Tribolium castaneum (Herbst), Sitophilus spp., Rhyzopertha dominica (Fauvel), and Cryptolestes ferrugineus (Stephens). Using all the market and sampling month data, there was a significant correlation between EMC and total number of insects recovered, but not between total number of insects and temperature. The average percentage of insect-damaged kernels (IDK) in the maize sampled across all the markets and sampling periods was 2.7 ± 0.2%, with a range between 0 and 21.4%. Using all the market and sampling month data, levels of insect damage tended to be positively correlated with maize moisture, but not temperature, and levels of insect damage increased with number of stored product insects recovered. The action threshold for aflatoxin in maize in Ghana is 15 ppb, but overall mean aflatoxin level was 19.8 ± 1.5 ppb and aflatoxin levels ranged from 0.3 to 132.2 ppb, with 53% of the samples having levels above 15 ppb. The mean fumonisin level was 1.2 ± 0.0 ppm, which is below the 4.0 ppm action threshold for Ghana. Our results show that aflatoxin levels were high in the market maize in Northern Region of Ghana and insects were prevalent, even though grain moisture tended to be relatively low, especially compared to the Middle Belt of Ghana.

On-farm maize insect pest and mycotoxin levels in Ghana: Presentation

Maize post-harvest losses are perennial in Ghana but reliable comparative information on on-farm losses of maize produced in the Middle and Northern Belts of Ghana is lacking. Two studies were conducted from September 2015 to February 2016 to identify factors contributing to on-farm losses of maize in these two Belts. In the Northern Belt, the study was conducted in six communities including Adubiyili, Diari, Pong-Tamale, Savelugu, Toroyili and Zamnayili; and in the Middle Belt, in Ejura, Sekyedumase and Amantin communities. Moisture content, percent weight loss, percent insect damaged kernels (IDK) on numerical basis (%IDKnb) and percent IDK by weight basis (%IDKwb), insect pest abundance, and mycotoxin levels were estimated. Moisture content values of maize at pre-harvest and heaping stages in all nine communities were below 15%. Sitophilus zeamais, Sitotroga cerealella, Cathartus quadricollis, and Carpophilus dimidiatus were found to attack maize onfarm in communities in the Middle Belt, but no adult insect pests were collected on pre-harvested maize in the Northern Belt. The %IDKnb values on-farm in all nine communities were < 2% per 250 g. Mean aflatoxin levels below 15 ppb were obtained from pre-harvested maize in both regions but levels above 15 ppb were obtained from heaped maize on-farm. Fumonisin levels of maize were below 4 ppm on pre-harvested and in heaped maize in both regions. Results show that heaping maize on-farm increases aflatoxin levels beyond the acceptable threshold level and should not be practiced.

Evaluation of five storage technologies to preserve quality composition of maize in Nigerian markets

Maize needs to be stored using good and safe postharvest management measures that will maintain the quality as at harvest. Insects and moisture must be controlled in storage to ensure quality and methods to achieve this, such as the use of reduced-risk measures were evaluated in this study, conducted February–December 2016. The efficacy of Bularafa diatomaceous earth (DE), Piper guineense (Botanical), PICS bags, ZeroFly® bags and permethrin (Rambo™) in preserving maize quality in Nigerian markets was assessed. A sixth treatment comprised maize in untreated polypropylene bags. Study locations were in four markets in Ibadan, Ilorin and Oyo towns. Each market had a storehouse, which contained experimental 100-kg bags. In each storehouse, each technology had six bags, which were all sampled monthly except in PICS treatment where six bags were destructively sampled every four months. Data taken in February) and December) showed that quality of maize in PICS bags was best having the lowest percentage of insect damaged kernels, numerical based (%IDKNB), — 0.01 ± 0.01and 0.02 ± 0.01; %IDKWB— weight based were 0.00 ± 0.00 and 0.00 ± 0.00); % weight loss (0.01 ± 0.01; 0.01 ± 0.01), % number of discolored maize (0.02 ± 0.01; 0.01 ± 0.01) and % seed germination (96.77 ± 0.53; 98.37 ± 0.35) respectively. Treated and untreated maize had mean aflatoxin levels below limit of detection of 5 ppb in February and December (0.47 and 1.66), respectively and their proximate composition were within ranges reported in literature. By December, untreated maize had the highest %IDKNB (1.42 ± 0.22), %IDKWB (1.07 ± 0.18), % weight loss (0.36 ± 0.07) and lowest % seed germination (88.09 ± 0.98) when compared to the evaluated storage technologies Therefore, these five technologies can be incorporated in integrated management of storage insect pests in storehouses.

Genetic diversity of Aspergillus flavus and occurrence of aflatoxin contamination in stored maize across three agro-ecological zones in Kenya

BackgroundAflatoxin contamination at pre- and post-harvest poses a serious challenge in achieving sustainable development goals on food security and food safety, in particular within the developing world. In Kenya, major outbreaks of aflatoxicoses have been reported and attributed to poor post-harvest storage practices. In this study, we conducted a cross-sectional survey within three Agro-ecological zones in Kenya, to determine occurrence and distribution of total aflatoxin in stored maize and the aflatoxigenicity potential of Aspergillus flavus in stored maize. The counties selected were: Kitui, Nakuru and Trans-Nzoia. Sampling sites were selected based on previous aflatoxicoses outbreaks (Kitui) and major maize production areas (Nakuru and Trans-Nzoia) where little information exists on the occurrence of aflatoxin contamination. One hundred and thirty (130) kernel maize samples were randomly collected. Aspergillus flavus was isolated by direct plating technique. Genetic diversity of the isolates was determined by PCR and single sequence repeats (SSR) microsatellites analysis. Positive strains were induced to produce B1 aflatoxins on yeast extract sucrose agar and quantified using competitive ELISA technique.ResultsTotal aflatoxin contamination of post-harvest stored maize samples between sites was significantly different (p = 0.000, < 0.05), with the highest contamination in Kitale at a mean of (9.68 µg/kg). A. flavus was isolated in 70% (N = 91) of the maize samples collected at post-harvest. A. flavus isolates with the highest aflatoxigenicity potential were from Nakuru County with mean aflatoxin level at 239.7 µg/kg. Genetic distance based on neighbor joining (NJ) clustered the A. flavus isolates into five main clusters including one clade with an admixture. Principal coordinate analysis showed five distinct clusters with both axes explaining 60.17% of the variance.ConclusionThis study showed widespread distribution of aflatoxin contamination and a highly toxigenic A. flavus in stored maize in three major agro-ecological zones in Kenya. These results suggest a potential health risk of aflatoxin outbreaks under favorable conditions within these areas, thus calling for more investigations.

Nutrient and aflatoxin contents of traditional complementary foods consumed by children of 6-24months.

The nutrient composition and safety of complementary foods have recently become areas of concern, especially with regard to aflatoxin contamination which has been found to adversely affect health outcomes. This study presents the nutrient and aflatoxin contents of complementary foods consumed by children (6–24 months) and infants and young child feeding practices of mothers from two districts in eastern and southern Zambia. A total of 400 mother–child pairs were recruited from Monze and Chipata districts, and data on breastfeeding and complementary feeding practices were collected twice at 3‐month interval using a structured questionnaire. Samples of two traditional complementary foods (Maize Nshima and Maize porridge) were collected from the mothers and analyzed for nutrient contents and aflatoxin contamination. The results showed that there is a high level of awareness on exclusive breastfeeding among mothers. Fat, protein, carbohydrate, and ash contents of Maize nshima from Chipata were significantly lower (p < .05) compared to those from Monze district except for starch and sugar. Monze mothers preferred to prepare a thicker Maize nshima and Maize porridge compared to their Chipata counterparts. The aflatoxin contamination showed that the Maize porridge samples from Chipata were the most contaminated with mean aflatoxin content of 5.8 ± 15.93 mg/100 g, while Maize nshima was the most contaminated of the two complementary foods from Monze districts with mean aflatoxin level of 3.8 ± 6.41 mg/100 g. There were significant (p < .05) positive correlations between fat and aflatoxin contents for Chipata samples (r = .12409) and for Monze samples (r = .13666). The traditional complementary foods studied were found to be low in fat and protein and high in aflatoxin contamination. Thus, it is imperative that best practices and interventions are designed and introduced to reduce the possible lethal health implications of consumption of such complementary foods by children under 5 years.