Ochratoxin A kinetics: a review of analytical methods and studies in rat model.

Ochratoxin A (OTA) is a thermostable mycotoxin that contaminates a great variety of foodstuffs. It is nephrotoxic in all of the mammalian species tested, the pig being the most sensitive one; among rodents, rats are the most susceptible to OTA carcinogenicity. Kinetics, by studying the absorption, distribution, metabolism and excretion of xenobiotics, is an important tool in the extrapolation of animal toxicity data for human risk assessment. The most important kinetic studies performed with OTA in rats are reviewed, together with the different methods used for OTA quantification in biological matrices. Twelve studies in Wistar, Sprague-Dawley or F344 rats, using radiolabeled OTA or TLC, HPLC-FLD or LC/MS have been summarized. Very often methods validated for food have been directly applied to tissues. Strain, sex and age differences have been detected but the interpretation is difficult due to the different experimental conditions, and the connection of the several factors that may account for these differences.

An approach to the toxicity and toxicokinetics of aflatoxin B1 and ochratoxin A after simultaneous oral administration to fasted F344 rats.

Humans are exposed to the hepatotoxic aflatoxin B1 (AFB1) and nephrotoxic ochratoxin A (OTA) through diet. However, kinetic and toxicological data after their co-administration are scarce. In this study, a single oral dose of AFB1 (0.25 mg/kg bw)+OTA (0.5 mg/kgbw) was administered to fasted F344 rats. Blood, liver and kidney were harvested at different timepoints for mycotoxins quantification, relative weight calculation, clinical biochemistry and histopathology analysis. Toxicity parameters pointed to acute toxicity in liver due to AFB1. No remarkable toxicity was observed in kidneys or immunological organs. Maximum observed concentrations in plasma (Cmax) were at 10 min and 2 h for AFB1 and OTA, respectively. AFB1 plasma concentration could indicate a rapid absorption/ metabolism of the mycotoxin; and AFB1 liver and kidney concentrations were lower than LOQ and LOD, respectively. For OTA, Cmax was 4326.2 µg/L in plasma. In kidney and liver Cmax was reached at 8 h and concentrations were very similar between both organs at all timepoints. Due to the low levels of AFB1, the effect of OTA on AFB1 kinetics could not be assessed. However, AFB1 seems not to affect OTA kinetics, as its profile seems very similar to kinetic studies performed only with OTA in similar conditions.

Effects of fasting and gender on ochratoxin A toxicokinetics in F344 rats.

Ochratoxin A (OTA) is a mycotoxin that causes renal tumors in rats, particularly in males. In previous kinetic studies performed in fed conditions (Vettorazzi et al., 2008), mature F344 male rats presented a significantly lower OTA bioavailability than females and young animals. The objective of the present study was to evaluate two factors which could explain this different kinetic profile: the presence of food and the male-specific protein alpha-2u-globulin. Therefore, a 24h kinetic study has been performed in rats under fasting conditions. Food ingestion has been controlled in both sexes during two months. The presence of alpha-2u-globulin in the urine has been analyzed with SDS-gradient mini-gel electrophoresis. Fasting tends to increase the maximum OTA plasma concentrations and the rate of absorption. The relative bioavailability is significantly increased under fasting conditions only in males. Mature males consumed a higher amount of food but, as the OTA dose administered, it was proportional to body weight. The reason why the OTA bioavailability is more affected in presence of food only in males is unclear. Several possibilities, such as differences in gastric emptying, OTA-food interactions and the involvement of alpha-2u-globulin are discussed.

Comparison between capillary electrophoresis and high performance liquid chromatography for the study of the occurrence of patulin in apple juice intended for infants.

Apple juice samples intended for infants purchased in Navarra (Spain) have been analyzed for PAT occurrence. Two capillary electrophoresis methods, based on a MEKC and a CEC system, and an HPLC method were evaluated for the aforementioned study. The CEC system gave less satisfying separations and several practical problems, so samples have been analyzed by MEKC and HPLC. Both methods have been comparable in terms of recovery, precision, limits of detection, volume of organic solvents used and adequate selectivity with regard to PAT and HMF. The analysis time in HPLC has been slightly lower than in the MEKC methodology. The PAT levels obtained in apple juice by both validated methods showed a strong correlation (p<0.001). Therefore, both methodologies are useful for the accurate quantification of patulin in this matrix. The PAT levels obtained in the 20 infant apple juices samples were in a range between

A different kinetic profile of ochratoxin A in mature male rats.

Ochratoxin A (OTA) is a mycotoxin that causes renal tumors in rodents, particularly in male rats. The present work explored the impact of gender and age on OTA toxicokinetics in F344 rats after a single oral dose (0.5mg/kg b.w.). OTA plasma concentrations were analysed with a validated HPLC-FLD method and a population approach (NONMEM VI) was used to perform the kinetic analysis and the one year exposure simulation (0.21 mg/kg daily). Maximum observed OTA concentration (CMAX(obs)) was at 2h in all groups except in mature females (6h). Mature females reached higher CMAX(obs) than males of the same age. Apparent volume of distribution, but not apparent total plasma clearance, increased significantly with body weight (P<0.01) resulting in the following values for the terminal plasma half life (h) in males: 219 (young), 264 (matures) and females: 191 (young), 205 (matures). In addition mature males showed a significant lower relative bioavailability. The simulation showed similar plasma concentrations in males and females after two-months. Thus, toxicokinetic does not seem to explain sex-differences in toxicity in long-term studies. However, the age and weight should be taken into account in short-term toxicological studies if sex-differences are studied.

A simple chemical method reduces ochratoxin A in contaminated cocoa shells.

Ochratoxin A (OTA) is a mycotoxin produced by Aspergillus and Penicillium species, which contaminates cocoa among other food commodities. It has been previously demonstrated that the toxin is concentrated in cocoa shells. The aim of this study was to assay a simple chemical method for ochratoxin A reduction from naturally contaminated cocoa shells. In order to determine the efficiency of the method, a high-performance liquid chromatography method with fluorescence detection was set up beforehand and validated. Ochratoxin A was extracted from cocoa shells with methanol-3% sodium bicarbonate solution and then purified with immunoaffinity columns. The recovery attained was 88.7% (relative standard deviation = 6.36%) and the limits of detection and quantification were 0.06 and 0.2 kg/kg, respectively. For decontamination experiments, the solvent extractor ASE 200 was used. First, aqueous solutions of 2% sodium bicarbonate and potassium carbonate were compared under the same conditions (1,500 lb/in2 at 40 degrees C for 10 min). Higher ochratoxin A reduction was obtained with potassium carbonate (83 versus 27%). Then, this salt was used under different conditions of pressure, temperature, and time. The greatest ochratoxin A reduction was achieved with an aqueous potassium carbonate solution (2%), at 1,000 lb/in2 at 90 degrees C for 10 min. This method could probably be applicable to the cocoa industry because it is fast and relatively economic. From the point of view of human health, the use of potassium carbonate, partially eliminated by rinsing the sample with water, does not likely represent a risk for human health.

Development and validation of a microemulsion electrokinetic chromatography method for patulin quantification in commercial apple juice.

A microemulsion electrokinetic chromatography (MEECK) method for patulin (PAT) quantification in apple juice samples has been developed. The effects of several important factors such as co-surfactant type, concentration of surfactant, acetonitrile percentage in the microemulsion, and running voltage and temperature were investigated to determine the optimum conditions. They resulted to be: a background electrolyte (BGE) composed of 25mM of sodium tetraborate, SDS (2.16%w/w), ethanol (6.49%w/w), n-octanol (0.82%w/w) and 2%v/v acetonitrile; applied voltage of +15kV; and a capillary temperature of 35 degrees C. PAT was detected at 276nm. Quantification and detection limits (LOQ and LOD) in apple juice samples were 8.0microgL(-1) and 3.2microgL(-1), respectively. Patulin was extracted from apple juice using ethyl acetate with a mean recovery value of 75.3% (RSD=4.5). This method was applied to the measurement of patulin in twenty commercial apple juice samples obtained from different Danish supermarkets. The PAT apple juice mean and median levels obtained were 35.9 and 10.9microgL(-1), respectively. The comparison with a previously validated micellar electrokinetic chromatography (MEKC) method for PAT analysis showed the suitability of using MEEKC for this mycotoxin analysis. However, the expectations of obtaining a higher efficiency and thus lower limits of detection and quantitation when using MEEKC were not met.

OTA-producing fungi isolated from stored cocoa beans.

AIMS: The aim of this study was to identify fungal populations in unroasted cocoa beans stored in Spain in order to evaluate the ochratoxin A (OTA)-production ability of certain Aspergillus isolates. METHODS AND RESULTS: Twenty batches of cocoa beans from different origins and with different OTA content were selected for this study. Three Aspergillus carbonarius and 13 Aspergillus niger aggregate strains isolated from these cocoa bean samples were selected to evaluate their OTA synthesis ability, being the only A. carbonarius isolates which are OTA producers [

Determination of patulin in commercial apple juice by micellar electrokinetic chromatography.

A novel and validated micellar electrokinetic capillary chromatography (MEKC) method using ultraviolet detection (UV) has been applied to the quantitative analysis of patulin (PAT) in commercial apple juice. Patulin was extracted from samples with an ethylacetate solution. The micellar electrokinetic capillary chromatography (MECK) parameters studied for method optimization were buffer composition, voltage, temperature, and a separation between PAT and 5-hydroxymethylfurfural (HMF) (main interference in apple juice PAT analysis) peaks until reaching baseline. The method passes a series of validation tests including selectivity, linearity, limit of detection and quantification (0.7 and 2.5 microgL(-1), respectively), precision (within and between-day variability) and recovery (80.2% RSD=4%), accuracy, and robustness. This method was successfully applied to the measurement of 20 apple juice samples obtained from different supermarkets. One hundred percent of the samples were contaminated with a level greater than the limit of detection, with mean and median values of 41.3 and 35.7 microgL(-1), respectively.

Alterations induced in vitro by ochratoxin A in rat lymphoid cells.

Ochratoxin A (OTA) is a nephrotoxic mycotoxin produced by species of the genus Penicillium and Aspergillus that is present in food and feed as a natural contaminant. It modifies the immune function in animals and inhibits the proliferative response of lymphocytes in vitro. The toxic effect of OTA (0.5, 2, 20 microM) in lympho-proliferative response, natural killer (NK) cell activity, cytotoxic T lymphocytes (CTL) activity and macrophages' bacteriolytic capability was studied in vitro after 1 hour of treatment. The proliferative response of lymphocytes to concanavalin A and lipopolysaccharide was not affected by OTA; the cytotoxic activity of NK cells was dose-dependent decreased; the CTL activity was significantly decreased at the lowest concentration; the bacteriolytic activity of macrophages varied only slightly. These in vitro results reproduced, at least in part, some effects detected previously in vivo. The protein synthesis inhibition and the oxidative metabolism of OTA coupled to the prostaglandin synthesis are probably implicated in NK cells' toxicity, because the effects were reverted by the addition of phenylalanine or piroxicam to the culture medium. The induction of apoptosis seems to be the principal mechanism of action in the CTL effect. The intracellular concentration of OTA after 1 hour was analysed by HPLC and was found to be proportional to the quantity of OTA added to the culture medium for the three cell types; the presence of phenylalanine and piroxicam on the culture medium did not change the intracellular OTA concentration.

[Organic pollutant residues of different origins in Navarra]. / Residuos de contaminantes orgánicos de diferentes orígenes en Navarra.

An analysis was made of residues of polychlorobyphenyls and trihalomethanes through GC-ECD and of herbicides through HPLC-PAD in samples proceeding from Navarra. Polychlorobyphenyls were detected (0.30 +/- 0.05 and 0.11 +/- 0.05 microg/l) in two of the 106 water samples analysed. Sixty-six food samples were analysed, and polychlorobyphenyls were only found in 8 samples of trout (dissimilar to dioxins: 21-194 microg/kg of fat; similar to dioxins: 41-139 microg/kg of fat). Of 107 fat samples analysed, polychlorobyphenyls dissimilar to dioxins were detected in two (27 +/- 5 and 30 +/- 5 microg/kg). Out of a total of 94 feed samples analysed, polychlorobyphenyls were detected in all the samples (12) of feed for aquaculture and their raw materials; the concentration of polychlorobyphenyls dissimilar to dioxins varied by an interval of 8-247 microg/kg of fat; polychlorobyphenyls similar to dioxins, between 18 and 107 microg/kg of fat. Contamination by polychlorobyphenyls of the fish from aquaculture could be due to the feed used in these exploitations. The average of trihalomethanes in the waters of the southern zone of Navarra (44 +/- 4 microg/l) was higher than those of the middle zone (16 +/- 1 microg/l) and the mountain zone (12 +/- 1 microg/l). The concentration of 99% of the samples fulfilled the norms on halomethanes. A relation was observed between muddiness and the concentration of trihalomethanes. Herbicide (cianazine) was only detected in one of the 135 samples of water analysed, with a concentration of (0.4 +/- 0.2 microg/l) which exceeded the established limit. The use of confirmation techniques (GC-MS, HPLC-MS/MS) would make it possible to validate these results and to expand the number of compounds analysed.

Residuos de contaminantes orgánicos de diferentes orígenes en Navarra / Organic pollutant residues of different origins in Navarra

Se analizaron residuos de policlorobifenilos, de trihalometanos mediante GC-ECD y de herbicidas mediante HPLC-PAD en muestras procedentes de Navarra.Se detectó policlorobifenilos (0,30 ± 0,05 y 0,11 ± 0,05 µg/l) en dos de las 106 aguas analizadas. Se analizó 66 muestras de alimentos, y sólo se halló policlorobifenilos en 8 muestras de trucha (no similares a dioxinas: 21-194 µg/kg de grasa; similares a dioxinas: 41-139 µg/kg de grasa). De 107 grasas analizadas, se encontró policlorobifenilos no similares a dioxinas en dos de ellas (27 ± 5 y 30 ± 5 µg/kg). De un total de 94 piensos, se detectó policlorobifenilos en todas las muestras (12) de pienso para acuicultura y sus materias primas; la concentración de policlorobifenilos no similares a dioxinas varió en el intervalo 8-247 µg/kg de grasa; la de los similares a dioxinas, entre 18 y 107 µg/kg de grasa. La contaminación por policlorobifenilos del pescado de acuicultura pudo deberse a los piensos utilizados en estas explotaciones.La concentración media de trihalometanos en las aguas de la Ribera de Navarra (44 ± 4 µg/l) fue superior a la de la zona media (16 ± 1 µg/l) y a la de la montaña (12 ± 1 µg/l). La concentración del 99% de las muestras cumple la normativa sobre halometanos. Se observó una relación entre la turbidez y la concentración de trihalometanos.Sólo se detectó un herbicida (cianazina) en una de las 135 muestras de agua analizadas, con una concentración (0,4 ± 0,2 µg/l) que superaba el límite establecido.La utilización de técnicas confirmatorias (GC-MS, HPLC-MS/MS) permitiría convalidar estos resultados, y ampliar el número de compuestos analizados

An analysis was made of residues of polychlorobyphenyls and trihalomethanes through GC-ECD and of herbicides through HPLC-PAD in samples proceeding from Navarra. Polychlorobyphenyls were detected (0.30 ± 0.05 and 0.11 ± 0.05 µg/l) in two of the 106 water samples analysed. Sixty-six food samples were analysed, and polychlorobyphenyls were only found in 8 samples of trout (dissimilar to dioxins: 21-194 µg/kg of fat; similar to dioxins: 41-139 µg/kg of fat). Of 107 fat samples analysed, polychlorobyphenyls dissimilar to dioxins were detected in two (27 ± 5 and 30 ± 5 µg/kg). Out of a total of 94 feed samples analysed, polychlorobyphenyls were detected in all the samples (12) of feed for aquaculture and their raw materials; the concentration of polychlorobyphenyls dissimilar to dioxins varied by an interval of 8-247 µg/kg of fat; polychlorobyphenyls similar to dioxins, between 18 and 107 µg/kg of fat. Contamination by polychlorobyphenyls of the fish from aquaculture could be due to the feed used in these exploitations. The average of trihalomethanes in the waters of the southern zone of Navarra (44 ± 4 µg/l) was higher than those of the middle zone (16 ± 1 µg/l) and the mountain zone (12 ± 1 µg/l). The concentration of 99% of the samples fulfilled the norms on halomethanes. A relation was observed between muddiness and the concentration of trihalomethanes. Herbicide (cianazine) was only detected in one of the 135 samples of water analysed, with a concentration of (0.4 ± 0.2 µg/l) which exceeded the established limit. The use of confirmation techniques (GC-MS, HPLC-MS/MS) would make it possible to validate these results and to expand the number of compounds analysed

Influence of roasting and brew preparation on the ochratoxin A content in coffee infusion.

A study of the effect of coffee processing in the ochratoxin A (OTA) level has been carried out from the green beans to the drinking form. The analysis of OTA has been carried out by an in-house validated HPLC method with fluorescence detection. The limits of detection were 0.04 microg/kg for green and roasted coffee, and 0.01 microg/L for coffee brew. Thirty-six green coffee samples of different origin (Colombia, Costa Rica, Brazil, Vietnam, India and Uganda) were analysed. The highest concentrations of OTA were found in Vietnamese samples -- Robusta species treated by dry processing -- (range 0.64-8.05 microg/kg), that also showed the highest percentage of defective beans (7.6%). These contaminated samples were roasted in a process that controlled loss of weight and color, as in the industry. A mean reduction of 66.5% was obtained, but the reduction seems to be heterogeneous. Coffee brew was prepared by the three brewing processes more utilized in Europe: moka, auto-drip and espresso. A reduction of the OTA level has been attained, being greater when using a espresso coffee maker (49.8%) than when using auto-drip (14.5%) or moka brewing (32.1%). Therefore, the method of coffee brew preparation plays a key role in the final OTA human exposure.

Occurrence of ochratoxin A in cocoa beans: effect of shelling.

The aim of this study was to investigate the influence of the shelling process on the presence of ochratoxin A (OTA) in cocoa samples. Twenty-two cocoa samples were analysed for the determination of OTA before (cocoa bean) and after undergoing manual shelling process (cocoa nib). In order to determine OTA contamination in cocoa samples, a validated high-performance liquid chromatography (HPLC) method with fluorescence detection was used for the quantitative analysis of ochratoxin A (OTA). In both types of samples, OTA was extracted with methanol-3% sodium hydrogen carbonate solution and then purified using immunoaffinity columns prior to HPLC analysis. Due to the fact that different recovery values were obtained for OTA from both types of samples, a revalidation of the method in the case of cocoa nibs was needed. Revalidation was based on the following criteria: Selectivity, limits of detection and quantification (0.03 and 0.1 microg kg(-1), respectively), precision (within-day and between-day variability) and recovery 84.2% (RSD = 7.1%), and uncertainty (30%). Fourteen of the twenty-two cocoa bean samples (64%) suffered a loss of OTA of more than 95% due to shelling, six samples suffered a loss of OTA in the range 65-95%, and only one sample presented a reduction of less than 50%. The principal conclusion derived from this study is that OTA contamination in cocoa beans is concentrated in the shell; therefore, improvements of the industrial shelling process could prevent OTA occurrence in cocoa final products.

Determination of ochratoxin A in wine using liquid-phase microextraction combined with liquid chromatography with fluorescence detection.

A liquid-liquid microextraction technique (LPME) has been applied to the extraction of ochratoxin A (OTA) from wine prior to its quantification by HPLC-fluorescence detection. OTA was extracted from wine, through 1-octanol immobilized in the pores of a porous hollow fiber, and introduced into 1-octanol inside the fiber. Recovery was 77%. The method was adequate for quantification of OTA in wine at levels within the range 0.25-10 ng/ml with a LOD of 0.2 ng/ml, and can be a simple and inexpensive alternative to the use of inmunoaffinity columns in order to quantify OTA levels in wine.

Validation of a high-performance liquid chromatography analytical method for ochratoxin A quantification in cocoa beans.

A validated high-performance liquid chromatography (HPLC) method with fluorescence detection for the quantitative analysis of ochratoxin A (OTA) in cocoa beans is described. OTA was extracted with methanol-3% sodium hydrogen carbonate solution and then purified with immunoaffinity columns before its analysis by HPLC. The validation of the analytical method was based on the following criteria: selectivity, linearity, limit of detection and quantification, precision (within- and between-day variability) and recovery, robustness and uncertainty. Detection and quantification limits were 0.04 and 0.1 mug kg(-1), respectively. Recovery was 88.9% (relative standard deviation = 4.0%). This method was successfully applied to the measurement of 46 cocoa bean samples of different origins. A total of 63% of cocoa bean samples was contaminated with a level greater than the limit of detection. The means and medians obtained for cocoa bean were 1.71 and 1.12 mug kg(-1), respectively. Surveillance controls should be set up in both crops and factories involved in transformation processes to avoid this mycotoxin in final products.

Contribution to the study of ochratoxin A in Spanish wines.

With the aim of assessing ochratoxin A (OTA) contamination in wines from a Spanish northern region and the influence of harvest conditions, the following samples were analysed: 40 wines (28 red and 12 white) obtained from grapes cultivated in three different places of the northern Spanish region of Navarra, but in different years, 20 samples in 1997 and 20 in 1998. Wine samples were provided by a viticultural experimental station with very consistent and controlled cultural and enological practices. A high-performance liquid chromatography (HPLC) method with fluorescence detection and immunoaffinity columns was employed (LOD = 0.05 ng ml(-1); method recovery = 101%). Eighty five per cent of the samples from 1997 showed OTA levels >0.05 ng ml(-1) (range 0.056-0.316 ng ml(-1)) and 15% of the samples from 1998 showed OTA levels above the LOD (range 0.074-0.193 ng ml(-1)). Averages detected in 1997 positive samples were 0.185 ng OTA ml(-1) wine (SD = 0.023) in white wine samples (n = 6) and 0.160 ng ml(-1) (SD = 0.119) in the red wine samples (n = 11). These differences between contamination by OTA in the samples from the two different years were attributed to the different quality of the grapes, due to the bad climate in 1997. The possibility of the loss of the mycotoxin was excluded by the analysis of OTA in contaminated wine during 12 months. This study showed that OTA is stable in wine for at least 1 year.

A sensitive method for the determination of gemfibrozil in human plasma samples by RP-LC.

A sensitive high-performance liquid chromatographic assay for the quantitative determination of gemfibrozil is described in this work. Ibuprofen was used as internal standard. The assay involved a single cyclohexane extraction and LC analysis with fluorescence detection. Chromatography was performed at 40 degrees C on a Hypersil ODS column. The mobile phase was a mixture of a solution of phosphoric acid 0.4% and acetonitrile (45:55). The method was validated. The detection limit of this method was 0.025 microg ml(-1); only 0.5 ml of the plasma sample was required for the determination. The calibration graph was linear from 0.05 to 0.5 microg ml(-1) and required a cubic equation from 0.5 to 30 microg ml(-1). Intra and inter-day precision (C.V.) did no exceed 15%. Mean recoveries were of 90.15+/-6.9% (C.V.'s<8%) for gemfibrozil and 93.10% for ibuprofen Applicability of the method was demonstrated by a pharmacokinetic study in normal volunteers who received gemfibrozil by oral route.

Determination of ochratoxin A in pig liver-derived pâtés by high-performance liquid chromatography.

A solid phase extraction procedure followed by HPLC analysis with fluorescence detection has been developed for ochratoxin A (OTA) in pâtés derived from pig liver. After a previous extraction of OTA with 60% acetonitrile, all the samples were purified through C8 columns. The percentage recovery was 85.7% and the lower limits calculated for accurate detection and quantitation were 0.56 ng/g and 0.84 ng/g respectively. The HPLC procedure showed a good linearity in the interval of equivalent OTA concentrations of 0.84 to 3 ng/g. Values <10% were obtained for precision in HPLC determinations performed (n = 3) and (n = 9). Stability of calibration standards and samples during the analytical procedure was also demonstrated. This method was successfully applied to 38 pig-derived pâtés and three samples were found to be positive with OTA levels above the detection limit. The highest concentration (1.77 ng/g) has been found in a home-made pâté.

Ocratoxina a en plasma humano: nuevos datos de exposición en España / Ochratoxin A in human plasma: new data of exposition in Spain

Se ha investigado la presencia de Ocratoxina A en plasma humano en la provincia de Granada, por medio del análisis de 83 muestras obtenidas de mujeres residentes en esa zona. El método analítico está basado en la extracción líquido-líquido, con posterior análisis por cromatografía líquida de alta resolución (HPLC) con detección de fluorescencia. Este método analítico ha sifo validaddo obteniéndose un límite de detección de 0,21 ng/mL. Se ha detectado la presencia de ocratoxina A en un 72 por ciento de las muestras. La concentración media hallada ha sido de 0,63 ng/mL, con una deviación estándar de 0,41 ng/mL y un rango de concentraciones entre 0,11 ng/mL y 6,96 ng/mL. Estos resultados son equiparables a los encontrados previamente en otras dos zonas del norte y del centro de España, y en los países del entorno. El análisis estadístico de los datos, por medio de un test de Kruskal-Wallis (n= 70; X2=4,591; p= 0,597), no evidenció que existiera ninguna diferencia significativa de los niveles plasmáticos de ocratoxina A en relación con la época del año en que fueron extraídas las muestras. Estos resultados constituyen una prueba más de la exposición generalizada de la población española a esta micotoxina, si bien el valor de la ingesta diaria de ocratoxina A calculado a partir de la concentración media hallada en el presente estudio, es muy inferior al máximo recomendado por el Comité de expertos sobre aditivos alimentarios de la Organización Mundial de la Salud (AU)