Moulds and mycotoxins in rice in Swedish retail

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1 Moulds and mycotoxins in rice in Swedish retail Elisabeth Fredlund, Anna Maria Thim, Ann Gidlund, Siv Brostedt, Marianne Nyberg, Monica Olsen To cite this version: Elisabeth Fredlund, Anna Maria Thim, Ann Gidlund, Siv Brostedt, Marianne Nyberg, et al.. Moulds and mycotoxins in rice in Swedish retail. Food Additives and Contaminants, 00, (0), pp.-. <0.00/0000>. <hal-00> HAL Id: hal-00 Submitted on Mar 0 HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

2 Food Additives and Contaminants Moulds and mycotoxins in rice in Swedish retail Journal: Food Additives and Contaminants Manuscript ID: TFAC-00-0.R Manuscript Type: Original Research Paper Date Submitted by the Author: -Sep-00 Complete List of Authors: Fredlund, Elisabeth; Microbiology Division, Research and Development Department, National Food Administration Thim, Anna Maria; Chemistry Division, Research and Development Department, National Food Administration Gidlund, Ann; Microbiology Division, Research and Development Department, National Food Administration Brostedt, Siv; Chemistry Division, Research and Development Department, National Food Administration Nyberg, Marianne; Chemistry Division, Research and Development Department, National Food Administration Olsen, Monica; Microbiology Division, Research and Development Department, National Food Administration Methods/Techniques: HPLC, Mycology Additives/Contaminants: Aflatoxins, Ochratoxin A Food Types: Rice

3 Page of Food Additives and Contaminants Fredlund et al. Moulds and mycotoxins Moulds and mycotoxins in rice from the Swedish retail market E. FREDLUND, A-M THIM, A. GIDLUND, S. BROSTEDT, M. NYBERG, & M. OLSEN Microbiology Division, Research and Development Department, National Food Administration, P.O Box, SE- Uppsala, Sweden Chemistry Division, Research and Development Department, National Food Administration, P.O Box, SE- Uppsala, Sweden

4 Food Additives and Contaminants Page of Abstract A survey of moulds and mycotoxins was performed on rice samples taken from the Swedish retail market. The main objective was to study mould and mycotoxin content in basmati rice and rice with a high content of fibre. Samples of jasmine rice as well as longgrain rice were also included. The samples were analysed for their content of ochratoxin A (HPLC), aflatoxin B, B, G, and G (HPLC, RIDA QUICK), and mould (traditional cultivation methods in combination with morphological analysis). The majority of samples were sampled according to the European Commission Regulation 0/00. Sub-samples were pooled and mixed before milling and both mould and mycotoxin analyses were performed on milled rice. The results showed that the majority of basmati rice (%) and many jasmine rice samples (0%) contained detectable levels of aflatoxin B (level of quantification = 0. µg aflatoxin kg - rice). Two samples of jasmine rice and 0 basmati rice samples contained levels over the regulated European maximum limits of µg kg - for aflatoxin B or µg kg - for total aflatoxins. Aspergillus was the most common mould genus isolated but also Penicillium, Eurotium, Wallemia, Cladosporium, Epicoccum, Alternaria and Trichotecium were found. The presence of Aspergillus flavus in % of the samples indicates that incorrect management of rice during production and storage implies a risk of mould growth and subsequent production of aflatoxin. Rough estimates showed that high rice consumers may have an intake of - ng aflatoxin per kg bodyweight and day from rice alone. This survey shows that aflatoxin is a common contaminant in rice imported to Europe. Keywords: basmati rice, aflatoxin, ochratoxin A, jasmine rice, retail, Aspergillus flavus, mould

5 Page of Food Additives and Contaminants Fredlund et al. Moulds and mycotoxins Introduction Rice (Oryzae sativa L) is one of the most important staple foods world-wide. Various varieties of rice are cultivated in different parts of the world and some of them are restricted to specific geographical regions, such as basmati rice in Pakistan and India (Bhattacharjee et al. 00) or jasmine rice in Thailand (International Rice Institute, The paddy rice or rough rice is harvested with the hull (or husk) when the water content is approximately 0%. The water content must be further reduced by drying to -% to eliminate microbiological activity during storage. The hull is removed and the remaining brown rice is processed further into various rice products such as whole-grain rice, parboiled rice, polished rice etc. The rice kernels can be of varies sizes and are classified as long-grain rice, medium-grain rice, and short-grain rice. During cultivation and subsequent handling of rice, kernels can be contaminated by moulds, which can grow and produce mycotoxins if conditions are favourable. The fungi may later die due to increased temperature or dry periods, but once produced, the stable mycotoxins will remain in the rice. Fungal activity depends on the moisture content and temperature, which can both vary significantly in a silo depending on its design and environmental factors. Postharvest treatment of rice, including adequate drying and conditions of storage, are crucial factors that will determine storage stability. Species of Fusarium have been isolated from newly harvested paddy rice (Pitt et al. ; Pacin et al. 00) and low levels of Fusarium-toxins have been detected (Kim et al. ; Park et al. 00). However, Fusarium-toxins are not considered a risk in rice (EC Regulation /00). In stored rice, the fungal flora is different from that in newly harvested rice.

6 Food Additives and Contaminants Page of Aspergillus spp. are common contaminants of stored rice (Kim et al. ; Park et al. 00; Sales and Yoshizawa 00) but species of Alternaria and Penicillium have also been reported (Pitt et al. ; Park et al. 00). Several studies have reported detectable levels of aflatoxins and ochratoxin A in rice from different countries including Cuba (Escobar and Regueiro 00), Korea (Park et al. 00), Malaysia (Abdullah et al. ), Sri Lanka (Bandara et al. ), the Philippines (Sales and Yoshizawa 00), the United Arab Emirates (Osman et al. ), India (Toteja et al. 00), and Côte d Ivoire (Sangare-Tigori et al. 00). Rice is a major cereal crop consumed by the European population, yet, reports on the actual mycotoxin content in rice is limited. This was also pointed out by the UK Food Standard Agency, which performed a survey of mycotoxins in rice in 00 (FSA, 00). Of the 00 rice samples analysed, none of the samples (including samples of basmati rice) contained mycotoxins over the EC regulated limits. Aflatoxins are genotoxic and carcinogenic substances that may induce liver cancer in both humans and animals. Aflatoxins are produced by several species of Aspergillus including A. flavus (aflatoxin B and B ) and A. parasiticus (B, B, G, and G ). A toxicological evaluation of aflatoxins was made by the Joint FAO/WHO Expert Committee of Food Additives (JECFA) in (WHO ) and by EFSA in 00 (CONTAM Panel 00), which both concluded that aflatoxins should be treated as carcinogenic food contaminants and the intake should be reduced to levels as low as reasonably achievable. Aflatoxins are genotoxic substances and therefore no tolerable daily intake (TDI) levels have been set for these toxins. However, an intake of one ng per kg bodyweight (bw) and day, corresponding to a life-time cancer risk of one extra cancer case for 0 individuals may be considered as an acceptable risk.

7 Page of Food Additives and Contaminants Fredlund et al. Moulds and mycotoxins Ochratoxin A is a nephrotoxic agent with immunotoxic, neurotoxic and teratogenic effects at higher dose levels. The toxin is produced by representatives of the two genera Penicillium and Aspergillus genera. Ochratoxin A was evaluated by JECFA in 00 (WHO 00) and by EFSA in 00 (CONTAM Panel 00). The PTWI for ochratoxin A was set to 00 ng per kg bw by JECFA (WHO 00) and to 0 ng per kg bw by EFSA (CONTAM Panel 00). Within the European Union, contamination of mycotoxins in food are regulated by the EC regulation /00, which regulates the maximum level (ML) of mycotoxins allowed in food, and the EC Regulation 0/00, which regulates the sampling for mycotoxin control of foods. The ML s in cereals for ochratoxin A is three µg kg -, for aflatoxin B two µg kg - and for the sum of aflatoxin B, B, G, and G four µg kg -. There are no regulated levels for mould in food. However, the presence of aflatoxin-producing species such as Aspergillus flavus, A. parasiticus and A. nomius or the ochratoxin-producing species Penicillium verrucosum, A. ochraceus, A. niger, A. carbonarius, and A. westerdijkiae may indicate the presence of these toxins. In 00, high levels of aflatoxin M was detected in milk in the companies own quality controls. The source of contamination was aflatoxin-contaminated rice bran, a by-product from a rice-mill, which was used as an ingredient in cattle feed in the south of Sweden. In contrast to milk, rice is not routinely controlled for the presence of aflatoxin. Rice has become an important stable food for the Swedish consumers. In 00, Swedes consumed. kg rice per person, which can be compared to. kg pasta per person, which is another important staple food (JORDBRUKSVERKET, 00).

8 Food Additives and Contaminants Page of The objective of this survey was to investigate the presence of mould, aflatoxins and ochratoxin A in rice available for purchase in he Swedish retail market. The results were used to estimate the intake of these mycotoxins from rice by Swedish consumers. Rapid semiquantitative methods, such as lateral-flow devices, for the analysis of aflatoxin in various food items (nuts, figs etc.) have been developed. To evaluate whether such methods may be suitable also for screening for aflatoxin in rice, one such method, RIDA QUICK Aflatoxin (R-Biopharm AG, Darmstadt, Germany) was used in parallel with HPLC analysis.

9 Page of Food Additives and Contaminants Fredlund et al. Moulds and mycotoxins Material and Methods Sampling and sample treatment The majority of rice samples were purchased from retail outlets in the South and Central parts of Sweden in Malmö, Stockholm, Uppsala, and Gothenburg. Rice samples were purchased from large retail stores, small local shops, health shops, shops with organic products and shops with products of mainly ethnical origin. Most samples ( of samples) were taken according to the alternative sampling plan for official control of mycotoxins in food (EC 0/00). Sub-samples (0.- kg) were pooled and mixed for min (IGF 00/S, Svea, Linköping, Sweden) and kg of the pooled sample was then ground to fine powder (Retsch GmbH & Co, Haan, Tyskland) and stored in room temperature until analysis. The particle size after grinding was below. mm and approximately 0% of the particles were below 0. mm. Water-activity (a w ) was analysed in all samples (Aqua Lab, Series TE, Decagon Devices, Inc., Pullman, WA, USA). Quantification and identification of mould Ground rice samples (0 g) were diluted (:0 and :00) in 0. % peptone water (BD, Becton, Dickinson and Company, Sparks, MD, USA) and poured or spread on % dichloran glycerol agar (DG; Samson et al. 00) plates. These were incubated in ± 0. C for seven days and colonies were thereafter counted and presented as the number of colony forming units (cfu) per g rice. The level of quantification was one log unit cfu g -, which equals 0 cfu g - rice.

10 Food Additives and Contaminants Page of Colonies of P. verrucosum was identified directly on DG by their bright orange-yellow reverse whereas other Penicillium-species were re-inoculated on CREA, Czapek, YES, and CYA and incubated at C for days for further morphological and biochemical characterization (Samson et al. 00). Colonies of Aspergillus were identified by morphological characteristics (Samson et al. 00) and potential colonies of A. flavus and A. parasiticus were confirmed on Aspergillus Flavus Parasiticus Agar (AFPA; Pitt et al. ). Analysis of aflatoxin B, B, G and G Ground rice samples (0 g) were transferred to glass bottles (00 ml) and mixed with 00 ml of % acetonitrile (HPLC grade) on a shaking table for 0 min. The samples were then filtered (Munktell V0) and six ml were further transferred to a MultiSep AflaZON +column (Romer Labs, Germany). Two ml were collected and nitrogen-evaporated to dryness before re-suspension in 00 µl acetonitrile:water:acetic acid (0:0:). The samples were filtered (0. µm) before injection (0 µl) on the HPLC column (C µm, 00 x. mm) equipped with a fluorescence detector (excitation nm, emission 0 nm). Derivatisation was performed with a KobraCell. The mobile phase was water:acetonitrile:methanol (::) supplemented with one mm KBr and. mm HNO, the flow was.0 ml min - and column temperature 0 C. The level of quantification (LOQ) was 0. µg kg - for aflatoxin B, B, G, and G. In addition to HPLC analysis, samples were also analysed for aflatoxin with the rapid method RIDA QUICK Aflatoxin by R-Biopharm AG, Darmstadt, Germany. Ten g of ground rice was mixed with 0 ml of 0 % methanol by vortexing for min. The samples were centrifuged (00 g) for two min and 0 µl were transferred to eppendorf tubes and mixed with 00 µl mobile solvent supplied with the RIDA QUICK kit. A hundred µl was applied

11 Page of Food Additives and Contaminants Fredlund et al. Moulds and mycotoxins on the lateral flow strip. Results were read after four (>0 µg kg - ), eight (0-0 µg kg - ), and (-0 µg kg - ) min. The LOQ was four µg aflatoxin kg - sample. Analysis of ochratoxin A Ground rice samples (0 g) were transferred to glass bottles (00 ml) and mixed with 00 ml of 0 % acetonitrile (HPLC grade) supplemented with NaHCO (0, %) on a shaking table for 0 min. The samples were then filtered (Munktell V0) and four ml of the sample was mixed with 0 ml 0.0 M PBS (Merck) and further transferred to an immunoaffinity column Ochraprep 0 (R. Biopharm Rhône Ltd.). The column was washed with 0 ml 0.0 M PBSbuffer (Merck) and then eluted with three ml methanol:acetic acid (:). The elute was nitrogen-evaporated to dryness before re-suspension in 00 µl mobile phase (acetonitrile:water:acetic acid; 0:0:) and injected (0 µl) on the HPLC column (Spherisorb µm, ODS 0 x. mm) equipped with a fluorescence detector (excitation nm, emission 0 nm). The flow was.0 ml min - and column temperature 0 C. The LOQ for ochratoxin A was 0. µg kg -. Intake estimations The daily intake of aflatoxins from a specific type of food depends on the concentration in the food and the amount of food consumed. To estimate the concentration of aflatoxin in rice mean values from this study were used as no additional data were available. Three different mean values were calculated (mean value for the total number of rice samples, for the basmati rice samples, and for the rice samples purchased in stores with products of mainly ethnical origin). Negative samples were included as half the LOQ, i.e. 0.0 µg kg -. This treatment of negative data may result in an overestimation of mycotoxin in rice.

12 Food Additives and Contaminants Page 0 of The consumption data for rice was based on a consumption study of Swedish consumers performed in - (Becker and Pearson ). This study included adult consumers between and years old from approximately 000 house holds. To compensate for the 00% increase in rice consumption for Swedish consumers reported by FAOSTAT, FAO (Food and Agriculture Organisation of the United Nations) Statistics Division 00, intake estimations were also performed based on a 00% increase of the consumption data from - (Becker and Pearson ). Consumers that originate from other countries than Sweden, such as India, Pakistan, Korea etc., are likely to consume rice more than - times per week as estimated for the mean consumer in the consumption survey Riksmaten - (Becker and Pearson ). These consumers are more likely to consume rice twice a day, seven days a week. Therefore, an estimated intake was also performed on this group of highconsumers. Aflatoxin intake estimations are based on results from analysis of aflatoxin in dried rice. However, recent research by Park et al. (00, 00) have shown that the aflatoxin content in rice may be reduced by approximately 0% during traditional cooking and 0% during pressure cooking. It is therefore more likely that the intake is lower in ready-to-eat rice than in dried rice due to the 0% aflatoxin reduction during cooking (Park et al. 00). Pressure cooking is rarely used in Swedish homes. Results & Discussion Rice samples A total of rice samples were purchased from retail outlets. The majority of rice samples were taken from local shops with products of mainly ethnical origin ( samples) and samples from larger retail stores ( samples), but samples were also taken from organic (five samples) and health food shops (three samples). The majority of samples were basmati rice but also rice with higher fibre content, i.e. brown rice or whole-grain rice, jasmine rice and 0

13 Page of Food Additives and Contaminants Fredlund et al. Moulds and mycotoxins long-grain rice were sampled (Table ). The group of rice samples with higher fibre content included long-grain rice (nine samples), basmati rice (three samples), jasmine rice (two samples), and short-grain rice (one sample). The group of organic rice samples included basmati rice (three samples), brown basmati rice (one sample), brown short-grain rice (one sample), and brown long-grain rice (four samples). Mycotoxin analysis All samples were analysed for aflatoxin B, B, G, G, and ochratoxin A with HPLC. Aflatoxin B was detected in % of the basmati rice samples and in 0% of the jasmine rice samples (brown rice included; Table ). Aflatoxin was not detected in short- or long-grain rice (brown rice included) nor in any of the organically grown rice samples (Table ). Aflatoxin G, G, and ochratoxin A were not detected in any of the rice samples. Seventy-six samples were also analysed for the total amount of aflatoxins with the rapid lateral flow method RIDA QUICK Aflatoxin (R-Biopharm AG). The RIDA QUICK method has previously been evaluated for aflatoxin detection in food items such as grain, soy, flour, nuts, and dried fruit and was included in this study to evaluate weather it can also be used as a screening method for aflatoxin in rice exceeding more than four µg kg -. Of the samples, samples contained more than four µg aflatoxin kg - (HPLC, LOQ 0. µg kg - ). These were identified with RIDA QUICK as positive (LOQ µg kg - ; Figure ) showing that no positive samples were identified as false negatives. Only one sample containing 0. µg aflatoxin kg - was falsely identified as above µg aflatoxin kg - by RIDA QUICK. The RIDA QUICK method gave a rough indication of the level of total aflatoxin in the rice samples (Figure ). The method RIDA QUICK Aflatoxin may therefore be used as a rapid

14 Food Additives and Contaminants Page of screening to identify rice samples that contain levels exceeding the European maximum limit for the sum of aflatoxins. However, samples that contain between and µg aflatoxin B kg -, thus exceeding the European maximum limit for aflatoxin B of µg kg -, will be missed in such a screening. Fungal species isolated from the rice samples Fungal contamination analysis was performed by dilution plating of the ground rice samples. The level of fungal contamination were generally low (log one to four cfu g - rice) and no significant difference could be found between the different types or origin of rice with regard to contamination level and fungal species isolated. Species of Aspergillus were the most frequently isolated genus but also species of Penicillium and Eurotium were common (Table ). The most frequently isolated species was A. candidus, being present in 0% of the rice samples and completely dominating in % of the samples (including samples of basmati rice, jasmine rice, long-grain rice, and brown rice). A. candidus has previously been reported to contaminate rice (Park et al. 00) and is known to contaminate other cereals (Samson et al. 00). However, this species is not known to produce any regulated mycotoxins. Less frequently found species were A. flavus (%), A. fumigatus (%), A. niger (%), P. polonicum (%), and P. chrysogenum (%). Occasional colonies belonging to the genus Wallemia, Cladosporium, Epicoccum, Alternaria, Trichotecium or to the taxonomical group of Zygomycetes were also isolated. A. fumigatus is commonly isolated from food and indoor environments. It does not produce any regulated toxins but may pose an environmental risk to the workers in the rice industry due to its pathogenicity and allergenic properties (Hedayati et al. 00).

15 Page of Food Additives and Contaminants Fredlund et al. Moulds and mycotoxins No correlation was found between the occurrence of A. flavus and the level of aflatoxin detected in the samples. This is likely due to the long storage period under dry conditions, which eventually leads to the reduction of viable mould count compared to the initial value. In addition to aflatoxin B and B, which are produced by both A. flavus and A. parasiticus, A. parasiticus is also able to produce aflatoxin G and G (Frisvad et al. 00). A. parasiticus was not isolated from the rice samples, nor were aflatoxin G and G detected. This may indicate that A. flavus is the main producer of aflatoxin in rice. A. niger was isolated from five samples, however, few A. niger are capable of producing ochratoxin A and the low incidence of potential ochratoxin-producing species correlated well with the absence of ochratoxin A. The low level of mould infection as well as the low water-activity (a w ) of the rice samples (0.0±0.0) may indicate that mould growth and mycotoxin production took place before drying and dehulling of the rice kernels. Intake and consumer health For genotoxic compounds, such as aflatoxins, the TDI cannot be used as a safety factor as the intake of such substances should be kept as low as reasonably possible. However, a provisional maximum TDI of one ng aflatoxin kg - bw day - may be used as a guiding value in the risk assessment of aflatoxin from food (JECFA ). Rough estimations of the intake of aflatoxin from rice for Swedish consumers showed that high-consumers (defined as the th percentile), of both women and men, that consume mainly basmati rice and rice bought in shops with products of ethnical origin were in the range of.-.0 ng aflatoxin kg - bw day - (Table ) and that the group of consumers that base all their meals on rice were in the range

16 Food Additives and Contaminants Page of of.-. ng aflatoxin kg - bw day - (Table ). The reduction of aflatoxin during cooking should be considered when discussing aflatoxin intake from rice. Park et al. (00, 00) showed that the aflatoxin content was reduced by 0% during cooking. The most extreme group of rice consumers is therefore likely to have an intake closer to.-. ng aflatoxin kg - bw day -, which is still above the guiding value of one ng aflatoxin kg - bw day -, rather than.-. ng aflatoxin kg - bw day -. Aflatoxin intake from more traditional sources of aflatoxin such as nuts, spices, milk, dried fruit and figs have previously been estimated for Swedish consumers to 0. ng aflatoxin kg - bw day - (Thuvander et al. 00). This study did not include rice. To reduce the aflatoxin content in rice, preventive measures such as improved farming systems, post-harvest handling, proper drying and storage must be taken. In addition, intensified internal and official control may be necessary to improve the quality of the rice available on the market. Concluding remarks The main sources of aflatoxin from food are traditionally considered to be nuts, maize and dried fruit. However, this study showed that % of the basmati rice and 0% of the jasmine rice samples analysed contained detectable levels of aflatoxin. Only few samples of other types of rice were included in this survey and conclusions on the aflatoxin prevalence in other rice than basmati and jasmine rice cannot be drawn. Aflatoxin was not only a common contaminant but also occurred in levels exceeding the EC limit values in % of the basmati samples and 0% of the jasmine rice samples. The mould content was generally very low in stored rice and no correlation was found with the content of aflatoxin. Intake estimations

17 Page of Food Additives and Contaminants Fredlund et al. Moulds and mycotoxins showed that high-consumers of rice (basmati and jasmine rice) have a higher intake of aflatoxin than recommended by JECFA (). Acknowledgement We acknowledge FOOD DIAGNOSTICS, Gothenburg, Sweden, for good collaboration on the RIDA QUICK Aflatoxin kit from R-Biopharm AG. References Abdullah N, Nawawi A, Othman I.. Survey of fungal counts and natural ocurrence of aflatoxins in Malaysian starch-based foods. Mycopathologia. :-. Bandara J, Vithanege A, Bean G.. Occurence of aflatoxin in paraboiled rice in Sri Lanka. Mycopathologia. :-0. Bhattacharjee P, Singhal, RS, Kulkarni, PR. 00. Basmati rice: a review. Int J Food Microbiol. :-. Becker W, Pearson M.. Kostvanor och näringsintag i Sverige - Metod och resultatanalys. Uppsala: Livsmedelsverket. [CONTAM PANEL] Panel on contaminants in the food chain. 00. Opinion of the scientific panel on contaminants in the food chain on a request from the commission related to ochratoxin A in food. The EFSA Journal. :-.

18 Food Additives and Contaminants Page of [CONTAM PANEL] Panel on contaminants in the food chain. 00. Opinion of the scientific panel on contaminants in the food chain on a request from the commission related to the potential increase of consumer health risk by a possible increase of the existing maximum levels for aflatoxin in almonds, hazelnuts and pistachios and derived products. The EFSA Journal. :-. Escobar A, Regueiro O. 00. Determination of aflatoxin B in food and feedstuffs in Cuba (0 through ) using an immunoenzymatic reagent kit (Aflacen). J Food Prot. ():-. Food Standards Agency. 00. Survey of retail rice for a range of mycotoxin. Food Survey information sheet /0 ( Frisvad J, Thrane U, Samson R, Pitt J. 00. Important mycotoxins and the fungi which produce them. New York: Springer. Hedayati M, Pasqualotto A, Warn P, Bowyer P, Denning D. 00. Aspergillus flavus: human pathogen, allergen and mycotoxin producer. Microbiology. :-. JORDBRUKSVERKET. 00. STATISTIK FRÅN JORDBRUKSVERKET Statistikrapport 00: Konsumtionen av livsmedel och dess näringsinnehåll. Kim E, Kim Y, Shon D, Ryu D, Chung S.. Natural occurrence of fumonisin B in Korean rice and its processed food by enzyme-linked immunosorbent assay. Food Sci Biotechnol. ():-.

19 Page of Food Additives and Contaminants Fredlund et al. Moulds and mycotoxins Osman N, Abdelgadir A, Moss M, Bener A.. Aflatoxin contamination of rice in the United Arab Emirates. Mycotox Res. ():-. Pacin A, Gonzáles H, Etcheverry M, Resnik S, Vivas L, Espin S. 00. Fungi associated with food and feed commodities from Ecuador. Mycopathologia. :-. Park W, Choi S, Hwang H, Kim Y. 00. Fungal mycoflora and mycotoxins in Korean polished rice destined for humans. Int J Food Microbiol. 0:0-. Park W, Lee C, Kim Y. 00. Fate of aflatoxin B during the cooking of Korean polished rice. J Food Prot. :-. Park W, Kim Y. 00. Effect of pressure cooking on aflatoxin B in rice. J Agric Food Chem. :-. Pitt J, Hocking A, Bhudhasamai K, Miscamble B, Wheeler K, Tanboon-Ek P.. The normal mycoflora of commodities from Thailand.. Beans, rice, small grains and other commodities. Int J Food Microbiol. :-. Pitt J, Hocking A, Glenn D.. An improved medium for the detection of Aspergillus flavus and A. parasiticus. J Appl Bacteriol. ():0-.

20 Food Additives and Contaminants Page of Sales A, Yoshizawa T. 00. Updated profile of aflatoxin and Aspergillus section Flavi contamination in rice and its byproducts from the Philippines. Food Add Contam. ():-. Samson R, Hoekstra E, Frisvad J. 00. Introduction to food- and airborne fungi. Utrecht: Centraalbureau voor schimmelcultures. Sangare-Tigori B, Moukha S, Koudadio H, Betbeder A-M, Dano D, Creppy EE. 00. Cooccurence of aflatoxin B, fumonisin B, ochratoxin A and zearalenone in cereals and peanuts from Côte d'ivoire. Food Add Contam. (0): Thuvander A, Möller T, Enghardt Barbieri H, Jansson A, Salomonsson A-C, Olsen M. 00. Dietary intake of some important mycotoxins by the Swedish population. Food Add Contam. ():-0. Toteja G, Mukherejee A, Diwakar S, Singh P, Saxena B, Sinha K, Sinha A, Kumar N, Nagaraja K, Bai G, Krishna Prasad C, Vanchinathan S, Roy R, Sarkar S. 00. Aflatoxin B contamination of parboiled rice samples collected from different states of India: A multicentered study. Food Add Contam. ():-. WHO, Food Additives Series 0.. Safety evaluation of certain food additives and contaminants. In WHO Food Additives Series. Geneva: World Health Organisation. WHO, Food Additives Series. 00. Safety evaluation of certain mycotoxins in food. In WHO Food Additives Series. Geneva: World Health Organisation.

21 Page of Food Additives and Contaminants Fredlund et al. Moulds and mycotoxins

22 Food Additives and Contaminants Page 0 of Figure captions Figure. Correlation between the aflatoxin content analysed by HPLC and the lateral flow method RIDA QUICK Aflatoxin (R-Biopharm) in rice samples. Each cross ( ) represents one rice sample. The level of quantification was 0. µg kg - rice for the HPLC method and four µg kg - rice for the RIDA QUICK method. The RIDA QUICK method only gave the result in intervals. 0

23 Page of Food Additives and Contaminants Fredlund et al. Moulds and mycotoxins Table Table. Number of samples and aflatoxin (µg kg - ) content for each type of rice (n= rice samples). The number of samples exceeding European maximum limits and the number of samples below LOQ (0. µg kg - ) are also given. The analytical uncertainty was 0. µg aflatoxin kg - rice (nd=not detected). Type of rice Number of Aflatoxin a (µg kg - ), samples Number of samples B > (µg kg - ) Aflatoxin total > (µg kg - ) Number of samples <LOQ interval for positive samples (mean) B B Total Basmati b 0.-. (.) 0.-. (0.) (.) Basmati c (.0) 0.-. (0.) (.) Jasmin b... Jasmin c 0.-. (.) 0.-. (.).0-. (.) high fibre content d 0.-. (.) 0.-. (.) (.) organic 0 nd nd nd long-grain 0 nd nd nd a aflatoxin G and G were not detected in any of the rice samples and are therefore not included in Table ; b rice with higher fibre content excluded; c rice with higher fibre content included; d one jasmin rice, one basmati rice.

24 Food Additives and Contaminants Page of Fredlund et al. Moulds and mycotoxins Table Table. The most common mould species isolated from the rice samples. Mould species Aspergillus spp. Isolated from number of samples (n=) Level of infection (log cfu g - ) A. candidus Dominating flora in rice samples from log -. to -. cfu g - A. flavus Mostly low levels (log -. cfu g - ) but dominating in one sample (log cfu g - ) A. fumigatus Mostly low levels (log -. cfu g - ) but dominating in one sample (log cfu g - ) A. niger Low levels (log -. cfu g - ) Penicillium spp. Mostly low levels (log -. cfu g - ) P. polonicum Dominating flora in two samples (log. and. cfu g - ) P. chrysogenom Low levels (log -. cfu g - ) Eurotium spp. Mostly low levels (log - cfu g - )

25 Page of Food Additives and Contaminants Fredlund et al. Moulds and mycotoxins Table Tabell. Intake estimations of aflatoxin from rice by different consumer groups (bw=bodyweight). Consumer group Woman, mean consumer Woman, high consumer c Man, mean consumer Man, high consumer c High consumer c with rice as the main stable food High consumer c woman/man if 00% increase of rice consumption from to 00 Rice intake (g dried rice Intake of aflatoxin (ng aflatoxin kg rice - kg bw - day - ) day - ) Mean value for all rice samples (. µg kg - ) a Mean value for the basmati rice samples including brown rice (. µg kg - ) a b b b b d... / e 0./../../.0 Mean value for the rice samples purchased in shops with ethnical products (. µg kg - ) a a mean value from HPLC analysis of aflatoxin B, B, G, and G. Samples with levels <LOQ were set to 0.0 µg kg -, i.e. half the LOQ; b consumption data based on results from Riksmaten - (Becker and Pearson ); c based on consumption data of the th percentile; d based on consumption of rice (0 g dried rice per meal) twice a day, seven days a week; e consumption data based on a 00% increase of rice consumption in Sweden

26 Food Additives and Contaminants Page of Fredlund et al. Moulds and mycotoxins Table from to 00 [FAOSTAT, FAO (Food and Agriculture Organisation of the United Nations) Statistics Division 00].

27 Page of Food Additives and Contaminants Fredlund et al. Moulds and mycotoxins... Figure HPLC (µg kg - ) < >0 RIDAQUICK (µg kg - )