Simultaneous determination of mycotoxin in commercial coffee

Mycotoxins are secondary metabolites produced by filamentous fungi that usually contaminate food products. Coffee is a natural product susceptible to mycotoxin contamination. The present study evaluates the presence of nivalenol, deoxynivalenol, T-2 and HT-2 Toxin, diacetoxyscirpenol, aflatoxin B₁, aflatoxin B₂, aflatoxin G₁, aflatoxin G₂, fumonisin B₁, fumonisin B₂, ochratoxin A, zearalenone, enniatin A, enniatin A₁, enniatin B, enniatin B₁, and beauvericin in coffee samples, using liquid chromatography tandem mass spectrometry (LC-MS/MS). The results show that zearalenone was not present in any sample. In the positive samples the contents of fumonisins ranged from 58.62 to 537.45 μg/kg, emerging mycotoxins ranged from 0.10 to 3569.92 μg/kg, aflatoxins ranged from 0.25 to 13.12 μg/kg, and trichothecenes, excepting nivalenol, ranged from 5.70 to 325.68 μg/kg. Nivalenol presented the highest concentrations, from 0.40 to 25.86 mg/kg. Ochratoxin A ranged from 1.56 to 32.40 μg/kg, and five samples exceeded the maximum limit established by the European Commission.     

Multiple mycotoxin co-occurrence in maize grown in three agro-ecological zones of Tanzania

In this study, the co-occurrence of multiple mycotoxins in maize kernels collected from 300 households' stores in three agro-ecological zones in Tanzania was evaluated by using ultra high performance liquid chromatography/time-of-flight mass spectrometry (TOFMS) with a QuEChERS-based procedure as sample treatment. This method was validated for the analysis of the main eleven mycotoxins of health concern that can occur in maize: aflatoxin B₁ (AFB₁), aflatoxin B₂ (AFB₂), aflatoxin G₁ (AFG₁), aflatoxin G₂ (AFG₂), ochratoxin A (OTA), deoxynivalenol (DON), fumonisin B₁ (FB₁), fumonisin B₂ (FB₂), HT-2 toxin, T-2 toxin and zearalenone (ZEN). From each zone one major maize producing district for home consumption was chosen and 20 villages for each district were randomly selected for sampling. All mycotoxins of health concern, except for T-2 toxin, were detected in the maize samples. Particularly high levels of AFB₁ (50%; 3–1,081 μg kg⁻¹), FB₁ (73%; 16–18,184 μg kg⁻¹), FB₂ (48%; 178–38,217 μg kg⁻¹) and DON (63%; 68–2,196 μg kg⁻¹) were observed. Some samples exceeded the maximum limits set in Tanzania for aflatoxins or in European regulations for other mycotoxins in unprocessed maize. Eighty seven percent of samples were contaminated with more than one mycotoxin, with 45% of samples co-contaminated by carcinogenic mycotoxins, aflatoxins and fumonisins. Significant differences in contamination pattern were observed among the three agro-ecological zones. The high incidence and at high levels (for some) of these mycotoxins in maize may have serious implications on the health of the consumers since maize constitute the staple food of most Tanzanian population. Effective strategies targeting more than one mycotoxin are encouraged to reduce contamination of maize with mycotoxins.     

Deoxynivalenol in the wheat milling process and wheat-based products and daily intake estimates for the Southern Brazilian population

Fusarium head blight of wheat is caused by the Fusarium species that produces mycotoxins, such as deoxynivalenol (DON). The distribution of DON in wheat products can lead to high economic and health impacts. The objective of this study was to evaluate the natural distribution of DON in the wheat milling process and wheat-based products, as well as the daily intake estimates for the Southern Brazilian population. The fractions of wheat grains (milled wheat, finished flour and bran) were produced in a mill. Additionally, wheat-derived products, such as pasta, bread and crackers were analyzed. The bran fraction had the highest mean concentration of DON (2278 μg kg⁻¹), followed by milled wheat and finished flour (1895 μg kg⁻¹ and 1305 μg kg⁻¹). The distribution factor in the finished flour (69%) fraction demonstrates that DON was reduced when compared to milled wheat, by contrast of bran fraction that presents higher DON levels (120%). A percentage of 35% bran, 35% finished flour and 30% milled wheat samples would not be in compliance with future Brazilian regulations for DON levels. From the wheat-based products analyzed, 17% of whole bread and 10% of salted cracker products were contaminated with DON, with a median of 437 μg kg⁻¹ and 624 μg kg⁻¹, respectively. The finished flour was the fraction that most contributes to the daily intake of DON in Southern Brazil, representing 89.6% of the provisional maximum tolerable daily intake.     

Isolation and characterization of Pseudomonas otitidis TH-N1 capable of degrading Zearalenone

Zearalenone (ZEA) is a nonsteroidal estrogenic mycotoxin produced by various Fusarium species and causes hyperestrogenism and related toxicosis of farm animals and humans. The present study aimed to isolate and identify ZEA-resistant bacteria from rumen in order to develop some strategies for detoxifying ZEA-contaminated food and feed. A bacterial strain was isolated from the rumen contents for its ability to utilize ZEA as the sole carbon and energy source. The isolate was an aerobic, Gram-negative, rod-shaped bacterium with single polar flagellum and was named Pseudomonas otitidis TH-N1 based on the morphology and 16S rRNA gene sequence. Meanwhile, the present study investigated that how various influence factors of P. otitidis TH-N1 could remove ZEA from a liquid medium. The optimal temperature, pH value, and concentrations of bacteria for the biodegradation of ZEA were 37 °C, 4.5, and 10⁹ cfu/ml, respectively. These results suggest that P. otitidis TH-N1 is a new bacterium found from the rumen and exhibited remarkable degradation activity of ZEA. It is probably a new bacterial resource to detoxify ZEA from ZEA-contaminated food and feed.     

Occurrence and molecular identification of anisakid nematodes isolated from Pacific cod (Gadus macrocephalus) caught off Korea

Anisakids nematodes from Pacific cod (Gadus macrocephalus) in Korea were investigated and their molecular identification was conducted, to assess the epidemiological role of Pacific cod in human anisakidosis in Korea. Totally 238 Pacific cod were caught from 5 different areas around Korean peninsula. Fish were dissected and carefully examined for collecting nematodes. PCR-RFLP and the subsequent sequencing were conducted for molecular identification of those nematodes. A high prevalence of infection (193/238, 81.1%) in Pacific cod was observed, and 1694 nematodes were collected. 79.1% (1340/1694) of the nematodes were found freely in the body cavity of Pacific cod, and the rest of them (20.9%, 354/1694) were in the digestive tract or attached to other organs. PCR-RFLP analysis using HinfI and RsaI restriction enzymes revealed 3 different banding patterns corresponding to Anisakis pegreffii, Hysterothylacium aduncum and hybrid genotype (Anisakis simplex × A. pegreffii), respectively. Of 1694 nematodes, 1280 (75.6%) were identified as A. pegreffii and 406 (24.0%) were H. aduncum. A. pegreffii occupied 84.0% (1125/1340) of the nematodes in the body cavity and 40.0% (132/330) of them in the digestive tract, but no nematodes were found in Pacific cod muscles.     

Inhibition of Fusarium culmorum by carboxylic acids released from lactic acid bacteria in a barley malt substrate

The effect of carboxylic acids, composed by both organic and phenolic acids, released in a barley malt substrate fermented by lactic acid bacteria was tested against Fusarium culmorum macroconidia and compared under different fermentation conditions. Phenolic acids released by Lactobacillus plantarum FST1.7 and Lactobacillus brevis R2Δ were quantified using a QuEChERS method coupled with a HPLC-UV/PDA system. Their concentration improved with increasing extract content of the barley malt-based substrate and reached maximal concentrations after 48 h of fermentation performed at optimum growth temperature. Generally, phenolic acids were produced at levels far below their minimal inhibitory concentration (MIC), and limited synergistic effects were observed when mixed with organic acids. The fungal growth suppression by the wort fermented by Lb. brevis R2Δ (95 ± 9 h total inhibition) could be fully explained by the presence of antifungal carboxylic acids, whereas only partially accounted for Lb. plantarum FST1.7 (198 ± 19 h). Organic acids were mainly responsible for the ability of LAB fermented wort to cause fungal inhibition, whereas phenolic acids took only a secondary role at the low concentrations released. Longer fermentation times favoured primarily organic acid release, whereas fermentation of higher malt extract substrates encouraged both organic and phenolic acids production. The understanding on how synergy works between antifungal compounds could help to identify strategies to further increase their concentration in wort, with potential to replace synthetic broths and for direct application in food application.     

Concentration and survey of phthalic acid esters in edible vegetable oils and oilseeds by gas chromatography-mass spectrometry in China

Now, there is a lack of information regarding the occurrence and the content of phthalic acid esters (PAEs) contamination in edible vegetable oils and oilseeds used for oil production in China. In this study, a method for determination of five PAEs was developed based on gas chromatography-mass spectrometry. Method recoveries for oils and oilseeds were 72.4–103.0% and 77.2–98.8%, respectively. RSDs of five analytes in oils and oilseeds were ranging from 1.22 to 8.64% and 0.62–9.37%, respectively. The LODs and LOQs were ranging from 0.10 to 0.79 and 0.33–2.60 μg/kg, respectively. Based on the established method, PAE concentrations in thirty-four edible oils and twenty-eight oilseeds were evaluated. Five and thirteen oil samples exceeded the upper limits 1.5 and 0.3 mg/kg set for di(2-ethtlhexyl) phthalate and dibutyl phthalate in China, respectively. The results obtained indicated that more concern and comprehensive legislation are still needed and mulriple issues should be considered when it comes to the PAEs contamination in edible vegetable oils.     

Aflatoxin contamination in unrecorded beers from Kenya – A health risk beyond ethanol

Samples of unrecorded opaque beers (n = 58; 40 based on maize, 5 on sorghum and 13 on other plants) and recorded wines (n = 8) in Kenya were screened for aflatoxins using a rapid ELISA technique followed by confirmation using liquid chromatography-tandem mass spectrometry. Six of the maize beers were obtained from Kibera slums in Nairobi County. Aflatoxin contamination was detected in six unrecorded beers (10%), but in none of the recorded wines. Remarkably, three of the aflatoxin positive samples were from the Kibera slums.The mean concentration of aflatoxins in the positive samples was 3.5 μg/L (range 1.8–6.8 μg/L), corresponding for an average consumption of 500 mL (1 standard drink) to a margin of exposure (MOE) of 36 (range: 15–58), which is considered as ‘risk’. On the other hand, the alcoholic strength of the aflatoxin positive samples had a mean of 4.3% vol (range 3.5–4.8%) corresponding to a MOE of 2.5 (range of 2.2–3.0) for the equivalent consumption volume. While aflatoxins pose a risk to the consumer, this risk is about 10 times lower than the risk of ethanol.The Joint FAO/WHO Expert Committee on Food Additives sets no acceptable daily intake for aflatoxins since they are genotoxic carcinogens and instead recommends for the reduction of aflatoxin dietary exposure as an important public health goal, particularly in populations who consume high levels of any potentially aflatoxins-contaminated food. Nevertheless, ethanol still posed a considerably higher risk in the unrecorded beers examined. However, consumers should be informed about aflatoxins, as these are an involuntary and unknown risk to them. In addition, producers should be educated about measures to reduce aflatoxins in alcoholic beverages.     

Antibiotic and synthetic growth promoters in animal diets: Review of impact and analytical methods

Food quality and safety have been a significant and pressing issue in recent years. In light of the FAO's definition of food security – the physical, social and economic access to sufficient and nutritious food – food safety plays a fundamental role. Animal feed and feeding is pivotal to the livestock industry, but the use of veterinary antibiotics (VAs) and synthetic growth promoters (SGP) diminishes the sustainability of the diets and can cause an accumulation of residues in animals (meat, milk and eggs) and the environment (water and soil pollution). Wastewater systems are another major pathway through which antibiotics and hormones can enter the environment, with negative consequences. In order to protect the planet through more sustainable feeding, the reduction of antibiotics and synthetic growth promoters is a key aim, in particular with the goal of reducing antibiotic resistance and allergies. Analytical methods play a crucial role in food analysis, to determine the presence of antibiotics and other additives. Recent methods are based on liquid chromatography with ultraviolet, fluorescence, or mass spectrophotometry detection, which is recognized as an essential technique in food analysis, able to identify more than 300 compounds in feed samples. In general, a monitoring program put in place to educate the population on the hazards of residues in animal products is necessary, in conjunction with a continuous decrease in the use of antibiotics and synthetic growth promoters in animal diets.     

Detection of selected corticosteroids and anabolic steroids in calf milk replacers by liquid chromatography–electrospray ionisation – Tandem mass spectrometry

The use of corticosteroids and anabolic steroids in food producing animals is regulated or banned in the European Union (EU). However, their use as growth promoters cannot be excluded. Milk replacers, considered by EU legislation as feeds, may be a good way of administration of these compounds. In order to improve the control of growth promoter utilization in animal husbandry and preventing possible consequences to animal welfare, we developed a method for multiresidue analysis of prednisolone, prednisone, dexamethasone, cortisone, cortisol, 17α- and 17β-boldenone and their precursor androstadienedione (ADD), testosterone, epitestosterone, 17α- and 17β-nandrolone, and trenbolone in powdered milk for calves. All analytes were extracted, after a common deproteinization and defatting sample pre-treatment, by a unique immunoaffinity column and analysed by liquid chromatography tandem mass spectrometry (LC–MS/MS) in both positive and negative electrospray ionization (ESI) modes. The method was validated according to the criteria of the Commission Decision 2002/657/CE. The analytical limits were from 0.39 to 0.73 ng mL⁻¹ for the decision limit (CCα) and 0.46–0.99 ng mL⁻¹ for detection capability (CCβ). The analysis of 50 samples of milk replacers for calves, always revealed the presence of cortisol and cortisone (average concentrations 2.56 and 1.06 ng mL⁻¹, respectively), frequently testosterone and epitestosterone (1.24 and 0.63 ng mL⁻¹, respectively), occasionally β-nandrolone (0.82 ng mL⁻¹) and prednisolone (0.41 ng mL⁻¹). The other anabolic steroids were never found.     

Biopreservation potential of lactic acid bacteria from Andean fermented food of vegetal origin

Microbial fermentations have long represented a way of natural biopreservation of raw materials, which frequently originated new food products. Among them, traditionally fermented products still manufactured by native populations all around the world are source of lactic acid bacteria (LAB) strains with high biotechnological potential. LAB are food grade microorganisms and therefore a good alternative to chemicals to be applied in food preservation. A total of 130 LAB isolates recovered from “chicha” and “tocosh”, traditional fermented Andean products of vegetal origin, were screened for antimicrobial activities against spoiler fungi Meyerozyma guilliermondii CECT 1021 (synonym Pichia guilliermondii), Penicillium roqueforti CECT 2905^NT, Aspergillus oryzae CECT 2094^NT and Aspergillus niger CECT 2807 as well as against foodborne pathogens Escherichia coli O157:H7 CECT 5947, Listeria innocua CECT 910^T and Salmonella enterica subsp. enterica serovar Typhi CECT 4138. LAB isolates represented nine species and four genera that exhibited a general inhibition of food pathogens and were also active against A. oryzae and M. guilliermondii while a poor inhibition of A. niger and P. roqueforti was produced. Antifungal activity of cell free supernatants (CFS) from seven selected strains grown in MRS was confirmed against toxigenic fungi Aspergillus parasiticus CECT 2681, Penicillium expansum CECT 2278 and Fusarium verticilloides CECT 2987 and also on the three foodborne bacteria included in the study. Phenyllactic and 3,5-Di-O-caffeoylquinic acids were identified as the predominant bioactive compounds in CFS by QuEChERS extraction with LC-MS-LIT detection approach. Four out of seven strains free of antibiotic resistances involving L. plantarum M5MA1 and M9MM1 from chicha and L. fermentum T3M3 and Lc. mesenteroides T1M3 from tocosh showed high potential to be used as biopreservatives in food applications.     

Determination,content analysis and removal efficiency of fining agents on ochratoxin A in Chinese wines

A simple and convenient HPLC-FD detection method for ochratoxin A (OTA) with a high detection limit and a short run time has been developed. OTA has been found in most samples of Chinese market wine, including domestic and imported wines, but the content was not very high. Only a few wines showed an OTA content that exceeded the EC and OIV limits, indicating that most Chinese market wines were safe. The OTA intake for Chinese from wine was 0.017 ng/kg (bw) per day, which was lower than the SCF and JECFA limits and also lower than in many other countries. This was mainly due to the low per capita wine consumption in China, but it is still necessary for the Chinese government and wine makers to monitor OTA levels in wine and to establish relevant regulations. An egg white treatment (0.20 mg/mL, 48 h) was the best removal method for OTA.     

Rapid multiresidue and multi-class screening for antibiotics and benzimidazoles in feed by ultra high performance liquid chromatography coupled to tandem mass spectrometry

An analytical strategy was developed for high-throughput screening of multiple antibiotics and two benzimidazoles in feed. Generic sample processing was applied without any purification step. After methanol extraction, the samples were centrifuged, concentrated, and analysed by ultra-high-performance liquid chromatography hyphenated to tandem mass spectrometry in the multiple reaction monitoring mode. Qualitative validation was carried out for more than 50 antibacterials of various classes, including aminocoumarin, amphenicols, beta-lactams, lincosamide, macrolides, diaminopyrimidine, quinolones, sulfonamides, streptogramin, pleuromutilin, polypeptide, quinoxaline, and tetracyclines, and also some benzimidazoles in feed at μg/kg level. Validation was done in accordance with the guidelines laid down in European Commission Decision 2002/657/CE for qualitative screening methods.This convenient, reliable, and sensitive method has been used successfully to monitor antibiotic residues in feeds.     

Three years of monitoring of PCDD/F,DL-PCB and NDL-PCB residues in bovine milk from Lombardy and Emilia Romagna regions (Italy): Contamination levels and human exposure assessment

In the three-years period 2012–2014, 160 cow milk samples from farms located in Lombardy and Emilia Romagna regions (Italy) were analyzed during the implementation of the Italian National Residues Monitoring Plan to assess the presence of PCDD/F, DL-PCB and NDL-PCB residues. The obtained contamination data were combined with cow milk consumption data from the Italian national dietary survey to estimate PCDD/F, DL-PCB and NDL-PCB human dietary exposure through the consumption of whole, semi skimmed and skimmed bovine milk. The exposure assessment was carried out separately for children, teenagers, adults and elderly. Average contamination levels of the analyzed samples were found to be 1.26 pg WHO-TEQ/g fat for the sum of PCDD/Fs and DL-PCBs and 9.30 ng/g fat for the sum of the 6 NDL-PCB indicators. PCB 126 was found to be the main contributor to the total WHO-TEQ. Using the upper bound approach, the estimated mean dietary intakes ranged from 0.07 pg WHO-TEQ/kg bw per day to 0.39 pg WHO-TEQ/kg bw per day for the sum of PCDD/Fs and DL-PCBs and considering exposure from whole milk. NDL-PCB mean dietary intakes resulted between 0.52 ng/kg bw per day and 2.86 ng/kg bw per day for consumption of whole milk. Children and teenagers were found to be the most exposed groups. This is the first time that Italian consumers exposure to NDL-PCBs is assessed using contamination data of cow milk produced in Italy.     

Phenolic fingerprint allows discriminating processed tomato products and tracing different processing sites

Tomatoes are important in human nutrition, as they are a source of carotenoids and phenolic compounds. However, transformation processes may alter the nutritional value of foods, decreasing the concentration of health-promoting compounds. This work aimed to explore the effects of industrial transformation on processed tomatoes (crushed pulp, puree and paste), as well as the effect of the different pre-processing technologies, rather than different manufacturing sites, in producing tomato paste. Results demonstrate that phenolics profiling can distinguish between different processed products as well as different paste pre-treatments (namely cold, warm and hot break), even though the latter underwent a final thermal treatment at >100 °C. Analogously, the different processing sites could be discriminated thanks to their characteristic phenolic fingerprint. The greatest differences identified were between conjugated forms of flavonoids, phenylpropanoids and lignans. The latter were the most labile phenolics, followed by flavonoids and then phenylpropanoids. Results provide evidence for the potential of phenolic fingerprint to support traceability of transformation processes and to investigate their effect on the nutritional value of processed tomatoes.     

Effect of sulfur dioxide and ethanol concentration on fungal profile and ochratoxin a production by Aspergillus carbonarius during wine making

Fungal profiles and ochratoxin A (OTA) accumulation during wine making were investigated using five different wine grape cultivars, Cabernet Sauvignon, Pinot Noir, Merlot, Syrah and Petit Verdot and the intrinsic influences caused by sulfur dioxide, ethanol and combine effect of ethanol and reducing sugar were analyzed using Cabernet Sauvignon and inoculation of Aspergillus carbonarius. Aspergillus spp. and Penicillium spp. were found as the major fungi in all winemaking processes and were highly correlated with OTA accumulation in wine. Most fungi died and OTA production decreased after 48 h of alcoholic fermentation, being consistent with the period when ethanol accumulation increased. The addition of SO₂ significantly inhibited the growth and OTA production of A. carbonarius with complete inhibition at 500 mg/L. When the ethanol concentration in the must increased to the range of 2–4%, growth and OTA production of A. carbonarius were significantly inhibited. Reducing sugar concentration had no significant effect on the growth and OTA production of A. carbonarius within the levels changing during the winemaking. Therefore, the increase of ethanol concentration played an important role in causing the decrease of fungal contamination and OTA accumulation during winemaking.     

Minerals in vitro bioaccessibility and changes in textural and structural characteristics of uncooked pre-germinated brown rice influenced by ultra-high pressure

Ultra-high pressure (UHP) is considered as an effective processing method to enhance micronutrients utilization efficiency in germinated brown rice (GBR), but there is little information available for the effects of UHP treatments on mineral bioaccessibility and related structural characteristics. Therefore, this work examined the changes induced by UHP in the in vitro bioaccessibility of selected minerals and structural and textural properties at pressures, as well as their potential relationship. UHP treatments were applied at 100, 300 and 500 MPa for 10 min, and 0.1 MPa as control. Proximate analysis showed that free fatty acids (FFA) and moisture in GBR greatly increased after UHP treatment. Three representative minerals with different levels were chosen to assess the bioaccessibility, including phosphorus (P), magnesium (Mg) and manganese (Mn). The results demonstrated that the minerals bioaccessibility, measured by percentage solubility, were the highest when at 300 MPa whereas it decreased at 500 MPa. Correspondingly, microstructure imaging by scanning electron microscope (SEM) showed that the gelatinization of starch granule occurred at 300 MPa and it became more obvious when increased to 500 MPa. Starch gelatinization significantly lowered the hardness of GBR grains, simultaneously accompanied with the decrease of cohesiveness, gumminess and resilience through texture profile analysis (TPA). Multivariate analysis by principal component analysis and canonical correspondence analysis indicated a highly intra-associated (p < 0.01) TPA parameters and a close correlation between the bioaccessibility and hardness, chewiness and springiness. These results provide information on minerals bioaccessibility and structural properties of uncooked GBR after UHP treatment, which could lay the foundation for further elucidating the correlation between structure and micronutrients bioaccessibility.     

Stable isotope and fatty acid compositions of monovarietal olive oils: Implications of ripening stage and climate effects as determinants in traceability studies

The quantitative variability of isotopic and fatty acid compositions in extra virgin olive oil was investigated in relation to variety, olive ripeness index and geographical origin. The study was carried out in two environments of Umbria region (central Italy), differing in annual/seasonal temperatures and rainfalls. Significant correlation was found between oil isotope compositions and climatic seasonal changes during fruit ripening. Moreover, significant isotopic differences among cultivars were related to the period of maximum oil accumulation in the fruits and to the fatty acid profile. A carbon kinetic isotopic effect could be associated with the fatty acid elongation from palmitic to stearic acid and to the unsaturation step leading from oleic to linoleic. No correlation was found between stable isotope and fatty acid compositions during fruit ripening. The analyzed cultivar and ripening effects on oil traceability issues are discussed in order to focus the resolution power of stable isotope methodologies and the possibility to distinguish monovarietal oils from the same area.     

Determination of heavy metals in selected black sea fish species

Heavy metals can be accumulated by marine organisms thought a variety of pathways, including respiration, adsorption and ingestion. The levels of heavy metals are known to increase drastically in marine environment through mainly anthropogenic activities. Fish are good indicators for the long term monitoring of metal accumulation in the marine environment. The aim of this study was to determine the levels of Cd, As, Hg, Pb, Zn and Cu in edible part and gill of seven most consumed Bulgarian fish species collected from north-east coast of Black Sea. These fish species are sprat (Sprattus sprattus sulinus), Mediterranean horse mackerel (Trachurus mediterraneus ponticus), Black sea gobies (Neogobius melanostromus), shad (Alosa pontica), Atlantic bonito (Sarda sarda), bluefish (Pomatomus saltatrix) and grey mullet (Mugil cephalus). The fish samples were collected during 2010. The analytical determination of As, Cd, Pb, Zn and Cu were performed by using flame and graphite furnace atomic absorption spectrometry after microwave digestion procedure. The total mercury determination was determined using a direct mercury analyzer (DMA-80). The metal concentration of analyzed elements was highest in the gill for all fish species. The maximum metal concentration was measured for Cu (1.40 mg kg⁻¹ w.w), Zn (11 mg kg⁻¹ w.w) and Pb (0.08 mg kg⁻¹ w.w) in muscle tissues of shad and sprat. The edible part of horse mackerel has the maximum value for Hg (0.12 mg kg⁻¹ w.w) while Atlantic bonito predominantly accumulates As (1.10 mg kg⁻¹ w.w). The analytical results obtained from this study were compared within acceptable limits for human consumption set by various health institutions.     

Fumonisin B1 and its co-occurrence with other fusariotoxins in naturally-contaminated wheat grain

The natural occurrence of fumonisin B₁ (FB₁) and its co-occurrence with zearalenone (ZEA), T-2 toxin and deoxynivalenol (DON) were surveyed in 103 winter wheat samples collected after four to six-month storage in family barns from different locations in Serbia. All 103 samples were mycotoxin positive. The mean concentrations of all mycotoxins except ZEA were greater in 2005 than in 2007. FB₁ was detected in 82.1% and 92.0% of all samples with ranges of 750-5400 μg kg⁻¹ (mean, 2079.45 μg kg⁻¹) and 750-4900 μg kg⁻¹ (mean 918.76 μg kg⁻¹) in 2005 and 2007, respectively. Moderate positive correlations were found between FB₁ and DON concentrations (r = 0.56 in 2005 and r = 0.54 in 2007) and between FB₁ and ZEA concentrations (r = 0.48 in 2005 and r = 0.60 in 2007), while a moderate negative correlation was detected between the production of FB₁ and T-2 toxin in 2007 (r = −0.33). This is the first report of FB₁ occurrence in naturally-contaminated wheat grain and its simultaneous occurrence with ZEA, DON and T-2 toxin in Serbia. Moreover, this is one of the rare reports presenting the occurrence of FB₁ on wheat in the world.