Fumonisins and zearalenone fed at low levels can persist several days in the liver of turkeys and broiler chickens after exposure to the contaminated diet was stopped.

Previous studies using zearalenone (ZEN) and fumonisins (FB) revealed alpha-zearalanol (α-ZOL) and FB1 in the liver of turkeys and chickens with no sign of toxicity. The aim of the present study was to determine whether contamination persists after distribution of a mycotoxin-free diet for several days. Turkeys and broilers were fed for 14 days with a diet containing respectively, 7.5 and 0.6 mg/kg of FB and ZEN, then fed for 0, 2 or 4 days with a mycotoxin-free diet. FB1 and total α-ZOL were the most abundant metabolites found, and their concentration decreased with time. The decrease was linear for FB1 (P < 0.001) and exponential for α-ZOL. Mean concentrations of FB1 on days 0, 2, and 4 were respectively, 4.9, 4, and 2.9 ng/g in turkeys, and respectively, 5, 2.3, and 1.3 ng/g in chickens. The decrease in concentration of FB1 with time was modeled by linear regression (P < 0.001). Mean concentrations of α-ZOL on days 0, 2 and 4, were respectively, 4.8, 0.8, and 0.5 ng/g in turkeys, whereas α-ZOL was only quantified in chickens on day 0 at 0.3 ng/g. A strong correlation was found between α-ZOL and ß-zearalenol (P < 0.001).

Toxicokinetics of Hydrolyzed Fumonisin B1 after Single Oral or Intravenous Bolus to Broiler Chickens Fed a Control or a Fumonisins-Contaminated Diet.

The toxicokinetics (TK) of hydrolyzed fumonisin B1 (HFB1) were evaluated in 16 broiler chickens after being fed either a control or a fumonisins-contaminated diet (10.8 mg fumonisin B1, 3.3 mg B2 and 1.5 mg B3/kg feed) for two weeks, followed by a single oral (PO) or intravenous (IV) dose of 1.25 mg/kg bodyweight (BW) of HFB1. Fumonisin B1 (FB1), its partially hydrolyzed metabolites pHFB1a and pHFB1b, and fully hydrolyzed metabolite HFB1, were determined in chicken plasma using a validated ultra-performance liquid chromatography-tandem mass spectrometry method. None of the broiler chicken showed clinical symptoms of fumonisins (FBs) or HFB1 toxicity during the trial, nor was an aberration in body weight observed between the animals fed the FBs-contaminated diet and those fed the control diet. HFB1 was shown to follow a two-compartmental pharmacokinetic model with first order elimination in broiler chickens after IV administration. Toxicokinetic parameters of HFB1 demonstrated a total body clearance of 16.39 L/kg·h and an intercompartmental flow of 8.34 L/kg·h. Low levels of FB1 and traces of pHFB1b were found in plasma of chickens fed the FBs-contaminated diet. Due to plasma concentrations being under the limit of quantification (LOQ) after oral administration of HFB1, no toxicokinetic modelling could be performed in broiler chickens after oral administration of HFB1. Moreover, no phase II metabolites, nor N-acyl-metabolites of HFB1 could be detected in this study.

Fumonisin B1, B2 and B3 in Muscle and Liver of Broiler Chickens and Turkey Poults Fed with Diets Containing Fusariotoxins at the EU Maximum Tolerable Level.

Although provisional maximum tolerable daily intake and recommended guidelines have been established for fumonisins (FB) in food, few data are available concerning levels of FB in edible animal tissues. Such data are of particular interest in avian species that can tolerate relatively high levels of fumonisins in their feed. Also, even if multiple contamination of animal feed by toxins produced by Fusarium is very frequent, little is known about the consequences of multiple contamination for FB levels in tissues. The aim of this study was to analyze the concentrations of FB in the muscle and liver of chickens and turkeys fed with FB alone and with FB combined with deoxynivalenol (DON), and with zearalenone (ZEN). Experimental diets were formulated by incorporating ground cultured toxigenic Fusarium strains in corn-soybean based feeds. Control diets were free of mycotoxins, FB diets contained 20 mg FB1+FB2/kg, and FBDONZEN diets contained 20, 5, and 0.5 mg/kg of FB1+FB2, DON, and ZEN, respectively. Animals were reared in individual cages with free access to water and feed. The feed was distributed to male Ross chickens from the 1st to the 35th day of age and to male Grade Maker turkeys from the 55th to the 70th day of age. On the last day of the study, the birds were starved for eight hours, killed, and autopsied for tissues sampling. No sign of toxicity was observed. A UHPLC-MS/MS method with isotopic dilution and immunoaffinity clean-up of samples has been developed for analysis of FB in muscle (n = 8 per diet) and liver (n = 8 per diet). Only traces of FB that were below the LOQ of 0.25 µg/kg were found in most of the samples of animals fed with the control diets. Mean concentrations of FB1, FB2, and FB3 in muscle were 17.5, 3.39, and 1.26 µg/kg, respectively, in chickens, and 5.77, 1.52, and 0.54 µg/kg in turkeys, respectively. In the liver, the respective FB1, FB2, and FB3 concentrations were 44.7, 2.61, and 0.79 µg/kg in chickens, and 41.47, 4.23, and 1.41 µg/kg, in turkeys. Cumulated level of FB1+FB2+FB3 in the highly contaminated samples were above 60 and 100 µg/kg in muscle and liver, respectively. The concentrations of FB in the tissues of animals fed the FBDONZEN diet did not greatly differ from the concentrations measured in animals fed the diet containing only FB.

Developmental Toxicity of Mycotoxin Fumonisin B1 in Animal Embryogenesis: An Overview.

A teratogenic agent or teratogen can disturb the development of an embryo or a fetus. Fumonisin B1 (FB1), produced by Fusarium verticillioides and F. proliferatum, is among the most commonly seen mycotoxins and contaminants from stale maize and other farm products. It may cause physical or functional defects in embryos or fetuses, if the pregnant animal is exposed to mycotoxin FB1. Due to its high similarity in chemical structure with lipid sphinganine (Sa) and sphingosine (So), the primary component of sphingolipids, FB1 plays a role in competitively inhibiting Sa and So, which are key enzymes in de novo ceramide synthase in the sphingolipid biosynthetic pathway. Therefore, it causes growth retardation and developmental abnormalities to the embryos of hamsters, rats, mice, and chickens. Moreover, maternal FB1 toxicity can be passed onto the embryo or fetus, leading to mortality. FB1 also disrupts folate metabolism via the high-affinity folate transporter that can then result in folate insufficiency. The deficiencies are closely linked to incidences of neural tube defects (NTDs) in mice or humans. The purpose of this review is to understand the toxicity and mechanisms of mycotoxin FB1 on the development of embryos or fetuses.

Oral and Intravenous Fumonisin Exposure in Pigs-A Single-Dose Treatment Experiment Evaluating Toxicokinetics and Detoxification.

We examined the toxicokinetics of fumonisin B1 (FB1) and its main metabolites after single dose application intravenously (iv) of 139 nmol FB1 or hydrolyzed FB1 (HFB1)/kg bodyweight (BW) in barrows (BW: 34.4 kg ± 2.7 kg), as well as the toxicokinetics of FB1, FB2, FB3 and FB1 bioavailability from oral exposure (3425 nmol FB1/kg BW, on top of ration). Additionally, detoxification efficacy of FumD (240 U/kg feed; 3321 nmol FB1/kg BW), a fumonisin esterase, was examined for oral fumonisin application. Urine and feces were collected quantitatively and serum samples were taken over a period of 120 h. Serum toxicokinetics of FB1iv showed a short distribution half-life of 6 min followed by a longer elimination half-life of 36 min. After HFB1iv administration, serum clearance was three times higher compared to FB1iv group (5.6 and 1.8 L/kg/h respectively) which together with a 5-times higher volume of distribution indicates that HFB1 is more rapidly cleared from systemic circulation but distributed more extensively into the extravasal space than FB1. The bioavailability of FB1 in orally exposed pigs was 5.2% (incl. metabolites). Moreover, we found a significant reduction of FB1 bioavailability by 90% caused by the action of fumonisin esterase in the gastrointestinal tract, clearly demonstrating the efficacy of FumD.

Determination of fumonisin B1 levels in body fluids and hair from piglets fed fumonisin B1-contaminated diets.

The levels of fumonisin B1 (FB1) residues in plasma, urine, feces and hair from 24 piglets fed FB1-contaminated diets containing 3.1, 6.1 or 9.0 µg FB1.g-1 for 28 days were determined using liquid chromatography coupled to mass spectrometry (LC-MS/MS). The levels of FB1 in plasma, urine, feces and pooled hair (n = 3) samples varied from 0.15 to 1.08 µg.L-1, 16.09-75.01 µg.L-1, 1.87-13.89 µg.g-1 and 2.08-8.09 ng.g-1, respectively. Significant correlations (r = 0.808-0.885; P < 0.001; N = 18) were found between FB1 intake and plasma FB1 on days 7, 14, 21 and 28. However, urinary FB1 correlated with FB1 intake only on days 7 and 14 (r = 0.561-572; P = 0.02; N = 18). A significant correlation (r = 0.509; P = 0.02; N = 24) was also found for the first time between FB1 in hair samples and FB1 intake. Plasma and urinary FB1 are good biomarkers of early exposure of pigs to low dietary FB1 levels, although plasma is recommended to assess prolonged exposure (>14 days). The possibility to evaluate hair as a biomarker of fumonisin exposure was established, although further studies are needed to provide physiologically based toxicokinetics of residual FB1 in the pig hair.

Nanocellulose coated with various free fatty acids can adsorb fumonisin B1, and decrease its toxicity.

The aim of this study was to evaluate the adsorption and biological properties of nanocellulose coated with free fatty acids (NCCFFAs). At first, nanocellulose was synthesized by acid hydrolysis, and then separately coated with different free fatty acids (FFAs), including lauric acid, alpha linoleic acid, oleic acid, and palmitic acid. Next, the serial concentrations of NCCFFAs (1, 10, 100, and 1000 µg/mL) was separately added to fumonisin B1 (FB1) at 1000 µg/mL, and separately incubated at 37 °C for 1, 2, and 3h. Then, the percentage of adsorption was calculated. In the next experiment, the viability of mouse liver cells was measured when they exposed to serial concentrations of NCCFFAs, FFAs, and FB1. This study showed that the increase of incubation time and concentration of NCCFFAs led to increase of FB1 adsorption. Although FFAs and NCCFFAs had no remarkable toxicity, the high toxicity was observed for FB1. Importantly, the toxicity of FB1 was highly decreased, when incubated together with FFAs or NCCFFAs. These novel adsorbents, NCCFFAs, can be used together with different foodstuffs to remove FB1.

Chronic exposure to deoxynivalenol has no influence on the oral bioavailability of fumonisin B1 in broiler chickens.

Both deoxynivalenol (DON) and fumonisin B1 (FB1) are common contaminants of feed. Fumonisins (FBs) in general have a very limited oral bioavailability in healthy animals. Previous studies have demonstrated that chronic exposure to DON impairs the intestinal barrier function and integrity, by affecting the intestinal surface area and function of the tight junctions. This might influence the oral bioavailability of FB1, and possibly lead to altered toxicity of this mycotoxin. A toxicokinetic study was performed with two groups of 6 broiler chickens, which were all administered an oral bolus of 2.5 mg FBs/kg BW after three-week exposure to either uncontaminated feed (group 1) or feed contaminated with 3.12 mg DON/kg feed (group 2). No significant differences in toxicokinetic parameters of FB1 could be demonstrated between the groups. Also, no increased or decreased body exposure to FB1 was observed, since the relative oral bioavailability of FB1 after chronic DON exposure was 92.2%.

Modified hydra bioassay to evaluate the toxicity of multiple mycotoxins and predict the detoxification efficacy of a clay-based sorbent.

Food shortages and a lack of food supply regulation in developing countries often leads to chronic exposure of vulnerable populations to hazardous mixtures of mycotoxins, including aflatoxin B(1) (AFB(1)) and fumonisin B(1) (FB(1)). A refined calcium montmorillonite clay [i.e. uniform particle size NovaSil (UPSN)] has been reported to tightly bind these toxins, thereby decreasing bioavailability in humans and animals. Hence, our objectives in the present study were to examine the ability of UPSN to bind mixtures of AFB(1) and FB(1) at gastrointestinally relevant pH in vitro, and to utilize a rapid in vivo bioassay to evaluate AFB(1) and FB(1) toxicity and UPSN efficacy. Isothermal sorption data indicated tight AFB(1) binding to UPSN surfaces at both pH 2.0 and 6.5, but substantially more FB(1) bound at pH 2.0 than 6.5. Site-specific competition occurred between the toxins when exposed to UPSN in combination. Importantly, treatment with UPSN resulted in significant protection to mycotoxin-exposed hydra maintained at pH 6.9-7.0. Hydra were exposed to FB(1), AFB(1) and FB(1) /AFB(1) combinations with and without UPSN. A toxic response over 92 h was rated based on morphology and mortality. Hydra assay results indicated a minimum effective concentration (MEC) of 20 µg ml(-1) for AFB(1), whereas the MEC for FB(1) was not reached. The MEC for co-exposure was 400 µg ml(-1) FB(1) + 10 µg ml(-1) AFB(1). This study demonstrates that UPSN sorbs both mycotoxins tightly at physiologically relevant pH levels, resulting in decreased bioavailability, and that a modified hydra bioassay can be used as an initial screen in vivo to predict efficacy of toxin-binding agents.

Toxic interaction between fumonisin B1 and moniliformin for cardiac lesions in Japanese quail.

This study examined the effects of fumonisin B1 (FB1) and moniliformin (M) on the heart of Japanese quail (Coturnix coturnix japonica). Three hundred and ninety day-old Japanese quail were randomly divided into four groups: 1) FB1 alone (FX), 2) M alone (MX), 3) FB1 and M (FM), and 4) chick mash alone (CX). We used three pen replicates of 35 quail per pen in groups FX, MX, and FM and three pen replicates of 25 quail per pen in group CX. Gross and microscopic changes in the heart were studied in nine birds (three birds per replicate) from each group at weekly intervals up to 28 days postfeeding (DPF). Ultrastructural changes were studied in the heart of three birds (one bird per replicate) from each group at 21 DPF. Thinning of the heart was the only significant gross lesion in group FX. In contrast, mild-to-severe cardiomegaly was a significant finding in groups MX and FM throughout the study. Microscopically, thinning of cardiomyocytes was evident at 7 DPF in group FX. In addition to the hypertrophy of cardiomyocytes evident as early as 7 DPF, myocardial karyomegaly, nuclear hyperchromasia, and myofibril disarray exhibiting a wavy pattern were more pronounced at 28 DPF in group MX. Similar but more severe lesions were observed in the FM combination group that included myocardial hemorrhages, vacuolar changes, hypertrophy of cardiomyocytes, focal myocarditis, and loss of myofibrils cross-striations. Via transmission electron microscopy, the maximum effect of FB1 toxicity was observed on mitochondria. In addition to an increase in the number of mitochondria, the mitochondria seemed invariably swollen and pleomorphic, although the outer membrane was intact, and the membrane cristae were usually distinct. Myofibrils seemed thinner, without much disruption in their architecture. Large numbers of vacuolar bodies of irregular size, both in the sarcoplasm and in between the myofibrils, were conspicuous in group FX. In contrast to group FX, the increase in number of mitochondria resulted in widespread separation of muscle fibers in group MX. In addition, the mitochondria were swollen and varied from round to oval to slightly elongated and occasionally forked, and vacuolation was rarely noticed in group MX. In the FM combination group, a significant increase in the number of mitochondria caused muscle fibers to look much thinner and assume a wavy pattern. We conclude that the effect of M on the heart is exaggerated in the presence of FB1. Although the overall interactive effect of FB1 and M was less than additive, the interactive effects between the two toxins for cardiac lesions were greater than additive to synergistic up to the second week, raising serious concerns on early age exposure to a combination of these two mycotoxins.

The kinetics of urinary fumonisin B1 excretion in humans consuming maize-based diets.

SCOPE: Fumonisins (FB) are mycotoxins found in maize. The purpose of this study was to (i) determine the relationship between FB(1) , FB(2) , and FB(3) intake and urinary excretion in humans, (ii) validate a method to isolate urinary FB on C(18) -SPE cartridges for international shipment, and (iii) test the method using samples from Guatemala. METHODS AND RESULTS: Volunteers (n = 10) consumed 206 grams/day of tortillas and biscuits prepared from masa flour and a product containing maize flour. Volunteers estimated their daily urine output and samples were analyzed for FB(1) , FB(2) , and FB(3) and hydrolyzed FB(1) . Only FB(1) was detected in urine suggesting lower absorption of FB(2) and FB(3) . Excretion was highly variable peaking soon after consumption began and decreasing rapidly after consumption stopped. Within 5 days after consumption ended, FB(1) was not detected in urine. In a study with eight volunteers, the average total urinary FB(1) was 0.5% of the intake. FB(1) was detected in 61% (107/177) of the samples collected in Guatemala. CONCLUSION: The results support the use of urinary FB(1) to assess ongoing exposure in population-based studies. However, relating the FB(1) concentration in urine to dietary intake of FB by individual subjects will be complicated due to interindividual variability and the rapidity of clearance.

Calcium montmorillonite clay reduces urinary biomarkers of fumonisin B1 exposure in rats and humans.

Fumonisin B1 (FB1) is often a co-contaminant with aflatoxin (AF) in grains and may enhance AF's carcinogenicity by acting as a cancer promoter. Calcium montmorillonite (i.e. NovaSil, NS) is a possible dietary intervention to help decrease chronic aflatoxin exposure where populations are at risk. Previous studies show that an oral dose of NS clay was able to reduce AF exposure in a Ghanaian population. In vitro analyses from our laboratory indicated that FB1 (like aflatoxin) could also be sorbed onto the surfaces of NS. Hence, our objectives were to evaluate the efficacy of NS clay to reduce urinary FB1 in a rodent model and then in a human population highly exposed to AF. In the rodent model, male Fisher rats were randomly assigned to either FB1 control, FB1 + 2% NS or absolute control group. FB1 alone or with clay was given as a single dose by gavage. For the human trial, participants received NS (1.5 or 3 g day⁻¹) or placebo (1.5 g day⁻¹) for 3 months. Urines from weeks 8 and 10 were collected from the study participants for analysis. In rats, NS significantly reduced urinary FB1 biomarker by 20% in 24 h and 50% after 48 h compared to controls. In the humans, 56% of the urine samples analysed (n = 186) had detectable levels of FB1. Median urinary FB1 levels were significantly (p < 0.05) decreased by >90% in the high dose NS group (3 g day⁻¹) compared to the placebo. This work indicates that our study participants in Ghana were exposed to FB1 (in addition to AFs) from the diet. Moreover, earlier studies have shown conclusively that NS reduces the bioavailability of AF and the findings from this study suggest that NS clay also reduces the bioavailability FB1. This is important since AF is a proven dietary risk factor for hepatocellular carcinoma (HCC) in humans and FB1 is suspected to be a dietary risk factor for HCC and oesophageal cancer in humans.

Toxicokinetics of fumonisin B2 in ducks and turkeys.

Two extraction steps combined with HPLC with fluorescence detection were developed to determine the toxicokinetics of fumonisin B(2) (FB(2)) in ducks and turkeys. The limit of quantification of the method was 25 ng of FB(2)/mL. The mean extraction was 63%. After intravenous administration (single dose: 1 mg of FB(2)/kg of BW), plasma concentration time curves were best described by a 2-compartment open model. In ducks, elimination half-life, mean residence time, and clearance of FB(2) were 32 min, 12.9 min, and 9.3 mL/min per kilogram, respectively. In turkeys, these toxicokinetics parameters were 12.4 min, 5 min, and 8.7 mL/min per kilogram, respectively. Only a small amount of FB(2) was detected in plasma after oral dosing of 10 mg of FB(2)/kg of BW.

Extrusion cooking with glucose supplementation of fumonisin-contaminated corn grits protects against nephrotoxicity and disrupted sphingolipid metabolism in rats.

SCOPE: Fumonisin B1 (FB1) is a mycotoxin found in maize and maize-based foods. It causes animal diseases and is a suspected risk factor for cancer and birth defects in humans. Extrusion cooking reduces FB1 concentrations in maize however toxicity caused by unknown degradation or FB1-matrix reaction products might persist. METHODS AND RESULTS: To test the efficacy of extrusion to reduce FB1 toxicity, Fusarium verticillioides fermented corn (= maize) grits (Batch-1= 9.7 ppm FB1; Batch-2= 50 ppm FB1) were extruded without (Batch-1E; Batch-2E) or with 10% glucose supplementation (Batch-1EG; Batch-2EG). FB1 concentrations were reduced 64% (Batch-2E) to 94% (Batch-1EG) after cooking. When the uncooked and processed grits were fed (50% w/w in rodent chow) to rats for up to 8 weeks, FB1 intakes averaged 354, 103, and 25.1 çg/kg body weight/day for Batch-1, Batch-1E and Batch-1EG and 1804, 698, and 222 çg/kg body weight/day for the Batch-2, Batch-2E and Batch-2EG, respectively. Nephrotoxicity including apoptotic lesions and elevated sphingoid base concentrations decreased in a dose-dependent manner in groups fed Batch-1, Batch-1E, Batch-2, Batch-2E, or Batch-2EG and was absent in the Batch-1EG group. CONCLUSION: Extrusion cooking, especially with glucose supplementation, is potentially useful to reduce FB1 concentrations and toxicity of FB1-contaminated maize.

[Fumonisin intake and human health]. / Consumo de fumonisinas y daños a la salud humana.

Fumonisins are mycotoxins that contaminate maize, disrupt the folate and sphingolipid metabolism, are associated with neural tube defects, and are considered by the International Agency for Research on Cancer (IARC) as possible human carcinogens. Since maize-based foods are significant components of the Mexican diet and there is a high prevalence of genetic susceptibility for folate deficiency among Mexicans, this essay presents international and national evidence of fumonisin exposure and the relevance that such exposure represents for Mexico.

Consumo de fumonisinas y daños a la salud humana / Fumonisin intake and human health

Las fumonisinas son una familia de micotoxinas que contaminan al maíz, alteran el metabolismo de los esfingolípidos y del folato, se asocian con defectos del tubo neural y están catalogadas por la Agencia Internacional de Investigación en Cáncer (IARC por sus siglas en inglés) como posibles carcinógenos humanos. Debido a que en México los derivados de maíz constituyen una parte importante de la dieta y existe alta prevalencia de población genéticamente susceptible a la deficiencia de folato, en este ensayo se presentan las evidencias mundiales y nacionales de la exposición a fumonisinas y la relevancia que para México representa la evaluación de esta exposición.

Fumonisins are mycotoxins that contaminate maize, disrupt the folate and sphingolipid metabolism, are associated with neural tube defects, and are considered by the International Agency for Research on Cancer (IARC) as possible human carcinogens. Since maize-based foods are significant components of the Mexican diet and there is a high prevalence of genetic susceptibility for folate deficiency among Mexicans, this essay presents international and national evidence of fumonisin exposure and the relevance that such exposure represents for Mexico.

Toxicokinetics and toxicological effects of single oral dose of fumonisin B1 containing Fusarium verticillioides culture material in weaned piglets.

Toxicokinetics and the toxicological effects of culture material containing fumonisin B(1) (FB(1)) were studied in male weaned piglets by clinical, pathological, biochemical and sphingolipid analyses. The animals received a single oral dose of 5 mg FB(1)/kg of body weight, obtained from Fusarium verticillioides culture material. FB(1) was detected by HPLC in plasma collected at 1-h intervals up to 6h and at 12-h intervals up to 96 h. FB(1) eliminated in feces and urine was quantified over a 96-h period and in liver samples collected 96 h post-intoxication. Blood samples were obtained at the beginning and end of the experiment to determine serum enzyme activity, total bilirubin, cholesterol, sphinganine (Sa), sphingosine (So) and the Sa/So ratio. FB(1) was detected in plasma between 30 min and 36 h after administration. The highest concentration of FB(1) was observed after 2 h, with a mean concentration of 282 microg/ml. Only 0.93% of the total FB(1) was detected in urine between 75 min and 41 h after administration, the highest mean concentration (561 microg/ml) was observed during the interval after 8 at 24 h. Approximately 76.5% of FB(1) was detected in feces eliminated between 8 and 84 h after administration, with the highest levels observed between 8 and 24 h. Considering the biochemical parameters, a significant increase only occurred in cholesterol, alkaline phosphatase and aspartate aminotransferase activities. In plasma and urine, the highest Sa and Sa/So ratios were obtained at 12 and 48 h, respectively.

Tissue persistence of fumonisin B1 in ducks and after exposure to a diet containing the maximum European tolerance for fumonisins in avian feeds.

Toxicity and persistence of fumonisin B1 (FB1) in liver, kidney and muscle were investigated in ducks fed 5, 10 and 20mg FB1+FB2/kg feed during force-feeding. Mortality and signs of toxicity were only obtained with 20mg/kg, whereas an increased Sa/So ratio was observed from 5mg/kg on. Persistence of FB1 was only found in liver (16 and 20 microg FB1/kg liver in ducks fed 10 and 20 mg FB1+FB2/kg feed, respectively). Toxicokinetic studies were conducted by the intravenous route (IV, single dose: 10mg FB1/kg body weight) and the oral route (single dose: 100mg FB1/kg body weight), in growing ducks and in ducks during force-feeding. After IV administration, serum concentration-time curves were described by a two-compartment open model. Elimination half-life and mean residence time of FB1 were 26 and 24 min, respectively, clearance was 19.3 ml/min/kg. After oral administration, bioavailability, elimination half-life, mean residence time and clearance varied during force-feeding and growth from 2-2.3%, 71-80 min, 200-188 min, 16.7-17 ml/min/kg, respectively. Taken together these results demonstrate that the risk of persistence of FB1 in ducks after force-feeding is very low, Sa/So being a good biomarker which increases before signs of toxicity and risk of persistence of FB1 in tissue (limit of detection 13 microg/kg).

Acute toxicity of a single gavage dose of fumonisin B1 in rabbits.

The aim of this study was to determine the clinical, pathological and mycotoxicological effects of oral administration of fumonisin B1 (FB1) in rabbits. Eighteen rabbits were randomly assigned to two experimental groups: control group, 0 mg FB1; fumonisin group, 31.5 mg FB1/kg body weight, corresponding to about 630 mg FB1/kg diet. Fumonisin administered as a single oral dose to rabbits resulted in acute toxicity, significantly interfering with body and liver weight. Serum biochemical analysis revealed a significant increase of total protein, alkaline phosphatase (AP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyltransferase (GGT), urea and creatinine in the group receiving FB1 compared to control animals, a finding characterizing hepatic and renal injury in this group. Urinary protein concentrations were markedly elevated at 12, 24, 48 and 72 h after dosing, although visible pathological abnormalities were not observed, probably because of rapid repair of the damage. FB1 was detected in feces, with a maximum concentration at 24 h after administration, indicating that the enterohepatic circulation is important in rabbits. FB1 concentrations found in urine were low, with peak elimination at 12 h after intoxication. The highest FB1 concentrations were observed in feces compared to urine and liver, demonstrating that feces are the main routes of excretion.

Toxicokinetics of fumonisin B1 in turkey poults and tissue persistence after exposure to a diet containing the maximum European tolerance for fumonisins in avian feeds.

The kinetic of fumonisin B1 (FB1) after a single IV and oral dose, and FB1 persistence in tissue were investigated in turkey poults by HPLC after purification of samples on columns. After IV administration (single-dose: 10mg FB1/kg bw), serum concentration-time curves were best described by a three-compartment open model. Elimination half-life and mean residence time of FB1 were 85 and 52min, respectively. After oral administration (single-dose: 100mg FB1/kg bw) bioavailability was 3.2%; elimination half-life and mean residence time were 214 and 408min, respectively. Clearance of FB1 was 7.6 and 7.5ml/min/kg for IV and oral administration, respectively. Twenty-four hours after the administration of FB1 by the intravenous route, liver and kidney contained the highest levels of FB1 in tissues, level in muscle was low or below the limit of detection (LD, 13microg/kg). The persistence of FB1 in tissue was also studied after administration for 9 weeks of a feed that contained 5, 10 and 20mg FB1+FB2/kg diet. Eight hours after the last intake of 20mg FB1+FB2/kg feed (maximum recommended concentration of fumonisins established by the EU for avian feed), hepatic and renal FB1 concentrations were 119 and 22microg/kg, level in muscles was below the LD.