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1.
Arch Toxicol ; 98(2): 425-469, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38147116

RESUMO

Fungi of the genus Alternaria are ubiquitous plant pathogens and saprophytes which are able to grow under varying temperature and moisture conditions as well as on a large range of substrates. A spectrum of structurally diverse secondary metabolites with toxic potential has been identified, but occurrence and relative proportion of the different metabolites in complex mixtures depend on strain, substrate, and growth conditions. This review compiles the available knowledge on hazard identification and characterization of Alternaria toxins. Alternariol (AOH), its monomethylether AME and the perylene quinones altertoxin I (ATX-I), ATX-II, ATX-III, alterperylenol (ALP), and stemphyltoxin III (STTX-III) showed in vitro genotoxic and mutagenic properties. Of all identified Alternaria toxins, the epoxide-bearing analogs ATX-II, ATX-III, and STTX-III show the highest cytotoxic, genotoxic, and mutagenic potential in vitro. Under hormone-sensitive conditions, AOH and AME act as moderate xenoestrogens, but in silico modeling predicts further Alternaria toxins as potential estrogenic factors. Recent studies indicate also an immunosuppressive role of AOH and ATX-II; however, no data are available for the majority of Alternaria toxins. Overall, hazard characterization of Alternaria toxins focused, so far, primarily on the commercially available dibenzo-α-pyrones AOH and AME and tenuazonic acid (TeA). Limited data sets are available for altersetin (ALS), altenuene (ALT), and tentoxin (TEN). The occurrence and toxicological relevance of perylene quinone-based Alternaria toxins still remain to be fully elucidated. We identified data gaps on hazard identification and characterization crucial to improve risk assessment of Alternaria mycotoxins for consumers and occupationally exposed workers.


Assuntos
Micotoxinas , Perileno , Humanos , Alternaria/metabolismo , Micotoxinas/toxicidade , Micotoxinas/análise , Mutagênicos/toxicidade , Mutagênicos/metabolismo , Lactonas/toxicidade , Lactonas/metabolismo , Medição de Risco , Contaminação de Alimentos/análise
3.
Aquat Toxicol ; 272: 106946, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38759525

RESUMO

Microplastics are ubiquitous environmental pollutants frequently detected in aquatic environments. Here we used the Atlantic salmon epithelial gill cell line (ASG-10) to investigate the uptake and effects of polystyrene (PS) microplastic. The ASG-10 cell line has phagocytotic/endocytic capacities and can take up clear PS particles at 0.2 and 1.0 µm, while PS at 10 µm was not taken up. As a response to the uptake, the ASG-10 cells increased their lysosomal activity. Furthermore, no effects on the mitochondria were found, neither on the mitochondrial membrane potential nor the mitochondria morphology (branch length and diameter). Interestingly, even a very high concentration of PS (200 µg/ml) with all tested particle sizes had no effects on cell viability or cell cycle. The environmental toxin Benzo(a)pyrene (B(a)P), a known inducer of CYP1A, is highly hydrophobic and thus sticks to the PS particles. However, co-exposure of B(a)P and PS the particles did not increase the induction of CYP1A activity compared to B(a)P alone. Our study contributes to the understanding of the cellular effects of PS particles using a highly relevant Atlantic salmon gill epithelium in vitro model.


Assuntos
Células Epiteliais , Brânquias , Microplásticos , Salmo salar , Poluentes Químicos da Água , Animais , Brânquias/efeitos dos fármacos , Brânquias/citologia , Microplásticos/toxicidade , Poluentes Químicos da Água/toxicidade , Células Epiteliais/efeitos dos fármacos , Linhagem Celular , Poliestirenos/toxicidade , Benzo(a)pireno/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Citocromo P-450 CYP1A1/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo
4.
Avian Pathol ; 42(4): 297-303, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23859215

RESUMO

Gizzard erosion and ulceration syndrome (GEU) was described for the first time in the 1930s. The main focus of early studies was on nutritional deficiencies and peroxidation of highly polyunsaturated fatty acids as causative factors. During the 1970s and 1980s the focus was moved towards toxic substances in the feed. Scott's review in 1985 concluded that overproduction of gastric acid induced by gizzerosine was a major cause of GEU. During the last decades, serotype 1 of fowl adenovirus A and Clostridium perfringens have been implicated as important pathogenic agents in the development of GEU in chickens. Although GEU is globally distributed and its subclinical form appears to be common in commercial poultry flocks, the condition is rarely mentioned in standard textbooks on poultry health. This regrettable fact is probably due in part to the lack of one definitive cause of the syndrome.


Assuntos
Infecções por Adenoviridae/veterinária , Fenômenos Fisiológicos da Nutrição Animal , Infecções por Clostridium/veterinária , Moela das Aves/fisiopatologia , Doenças das Aves Domésticas/etiologia , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/virologia , Ração Animal/efeitos adversos , Animais , Clostridium perfringens , Adenovirus A das Aves , Imidazóis/efeitos adversos , Mucosa/patologia , Micotoxinas/toxicidade , Especificidade da Espécie , Síndrome
5.
Cytotechnology ; 75(1): 63-75, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36713067

RESUMO

In order to ensure the proper use and interpretation of results from laboratory test systems, it is important to know the characteristics of your test system. Here we compare mitochondria and the handling of reactive oxygen species (ROS) in two gill epithelial cell lines, the well-known RTgill-W1 cell line from Rainbow trout and the newly established ASG-10 cell line from Atlantic salmon. Rotenone was used to trigger ROS production. Rotenone reduced metabolic activity and induced cell death in both cell lines, with RTgill-W1 far more sensitive than ASG-10. In untreated cells, the mitochondria appear to be more fragmented in RTgill-W1 cells compared to ASG-10 cells. Furthermore, rotenone induced mitochondrial fragmentation, reduced mitochondria membrane potential (Δψm) and increased ROS generation in both cell lines. Glutathione (GSH) and catalase is important to maintain the cellular oxidative balance by eliminating hydrogen peroxide (H2O2). In response to rotenone, both GSH and catalase depletion were observed in the RTgill-W1 cells. In contrast, no changes were found in the GSH levels in ASG-10, while the catalase activity was increased. In summary, the two salmonid gill cell lines have different tolerance towards ROS, probably caused by differences in mitochondrial status as well as in GSH and catalase activities. This should be taken into consideration with the selection of experimental model and interpretation of results. Supplementary Information: The online version contains supplementary material available at 10.1007/s10616-022-00560-0.

6.
Environ Health ; 11 Suppl 1: S6, 2012 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-22759506

RESUMO

BACKGROUND: The EU 6th Framework Program (FP)-funded Health and Environment Network (HENVINET) aimed to support informed policy making by facilitating the availability of relevant knowledge on different environmental health issues. An approach was developed by which scientific agreement, disagreement, and knowledge gaps could be efficiently identified, and expert advice prepared in a way that is usable for policy makers. There were two aims of the project: 1) to apply the tool to a relevant issue; the potential health impacts of the widely used plasticizers, phthalates, and 2) to evaluate the method and the tool by asking both scientific experts and the target audience, namely policy makers and stakeholders, for their opinions. METHODS: The tool consisted of an expert consultation in several steps on the issue of phthalates in environmental health. A diagram depicting the cause-effect chain, from the production and use of phthalates to potential health impacts, was prepared based on existing reviews. This was used as a basis for an online questionnaire, through which experts in the field were consulted. The results of this first round of consultation laid the foundation for a new questionnaire answered by an expert panel that, subsequently, also discussed approaches and results in a workshop. One major task of the expert panel was to pinpoint priorities from the cause-effect chain according to their impact on the extent of potential health risks and their relevance for reducing uncertainty. The results were condensed into a policy brief that was sent to policy makers and stakeholders for their evaluation. RESULTS: The experts agreed about the substantial knowledge gaps within the field of phthalates. The top three priorities for further research and policy action were: 1) intrauterine exposure, 2) reproductive toxicology, and 3) exposure from medical devices. Although not all relevant information from the cause-effect chain is known for phthalates, most experts thought that there are enough indications to justify a precautionary approach and to restrict their general use. Although some of the experts expressed some scepticism about such a tool, most felt that important issues were highlighted. CONCLUSIONS: The approach used was an efficient way at summarising priority knowledge gaps as a starting point for health risk assessment of compounds, based on their relevance for the risk assessment outcome. We conclude that this approach is useful for supporting policy makers with state-of-the-art scientific knowledge weighed by experts. The method can assist future evidence-based policy making.


Assuntos
Exposição Ambiental , Saúde Ambiental/métodos , Política Ambiental , Poluentes Ambientais/toxicidade , Prova Pericial , Ácidos Ftálicos/toxicidade , Animais , Poluentes Ambientais/farmacocinética , Humanos , Ácidos Ftálicos/farmacocinética , Formulação de Políticas , Medição de Risco , Inquéritos e Questionários
7.
Environ Int ; 157: 106804, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34352564

RESUMO

The Fusarium mycotoxin deoxynivalenol (DON) and its modified forms are present in most samples of grain and grain-based products. Due to the widespread presence of DON in these highly consumed food commodities, nearly all individuals are exposed to DON. Previous estimates of the dietary DON intake in Norway indicated that children's dietary intake is close to or exceed the TDI of 1 µg/kg bw/day for the sum of DON and three modified forms. One aim of the current study was to determine whether the concentrations of DON in morning urine differ between population groups like men, women, children, vegetarians, and pregnant women. An additional aim was to compare a set of models for estimating the dietary intake of DON based on urinary DON concentrations and also compare these models with DON-intakes estimated using food consumption data. DON and metabolites were detected in the morning urine from 256 out of 257 individuals and with concentrations in similar range as reported from other countries. Children have higher urinary DON-concentration than adults and elderly. The urinary DON-concentration in pregnant women and vegetarians did not differ from other adults. The estimated intake of DON was higher for children than for other age groups on a body weight basis. The correlations between different models for estimating DON-intake based on urinary concentration as well as based on individual food consumption were good (0.79-0.99), but with some outliers. We conclude that Norwegians are exposed to DON in the same range as reported from other countries and that children have a higher exposure than adults. Furthermore, we conclude that intake estimates based on urinary DON concentration is a useful tool for evaluation of the exposure at population level, but due to outliers, the estimates for individuals are uncertain. There are also uncertainties in intake estimates both from food consumption and from urinary DON concentration, and we could not conclude on which approach provides the most accurate exposure estimate.


Assuntos
Grupos Populacionais , Tricotecenos , Idoso , Biomarcadores , Feminino , Contaminação de Alimentos/análise , Humanos , Masculino , Noruega , Gravidez
8.
PLoS One ; 15(12): e0244000, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33320886

RESUMO

The aim of this study was to investigate the potential interference of cyanobacterial metabolites, in particular microcystins (MCs), with steroid hormone biosynthesis. Steroid hormones control many fundamental processes in an organism, thus alteration of their tissue concentrations may affect normal homeostasis. We used liquid chromatography-tandem mass spectrometry (LC-MS/MS) to investigate the modulation of 14 hormones involved in the adrenal steroid biosynthesis pathway using forskolin-treated H295R cells, following exposure with either microcystin-LR (MC-LR) alone, a mixture made up of MC-LR together with eight other MCs and nodularin-R (NOD-R), or extracts from the MC-LR-producing Microcystis aeruginosa PCC7806 strain or its MC-deficient mutant PCC7806mcyB-. Production of 17-hydroxypregnenolone and dehydroepiandrosterone (DHEA) was increased in the presence of MC-LR in a dose-dependent manner, indicating an inhibitory effect on 3ß-hydroxysteroid dehydrogenase (3ß-HSD). This effect was not observed following exposure with a MCs/NOD-R mixture, and thus the effect of MC-LR on 3ß-HSD appears to be stronger than for other congeners. Exposure to extracts from both M. aeruginosa PCC7806 and M. aeruginosa PCC7806mcyB- had an opposite effect on 3ß-HSD, i.e. concentrations of pregnenolone, 17-hydroxypregnenolone and DHEA were significantly decreased, showing that there are other cyanobacterial metabolites that outcompete the effect of MC-LR, and possibly result instead in net-induction. Another finding was a possible concentration-dependent inhibition of CYP21A2 or CYP11ß1, which catalyse oxidation reactions leading to cortisol and cortisone, by MC-LR and the MCs/NOD-R mixture. However, both M. aeruginosa PCC7806 and M. aeruginosa PCC7806mcyB- extracts had an opposite effect resulting in a substantial increase in cortisol levels. Our results suggest that MCs can modulate steroidogenesis, but the net effect of the M. aeruginosa metabolome on steroidogenesis is different from that of pure MC-LR and independent of MC production.


Assuntos
17-alfa-Hidroxipregnenolona/metabolismo , 3-Hidroxiesteroide Desidrogenases/antagonistas & inibidores , Desidroepiandrosterona/biossíntese , Inibidores Enzimáticos/farmacologia , Microcistinas/farmacologia , Microcystis/química , Linhagem Celular Tumoral , Família 11 do Citocromo P450/antagonistas & inibidores , Família 21 do Citocromo P450/antagonistas & inibidores , Humanos
9.
Toxins (Basel) ; 12(10)2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-33008105

RESUMO

This study determined the presence, levels and co-occurrence of mycotoxins in fish feeds in Kenya. Seventy-eight fish feeds and ingredients were sampled from fish farms and fish feed manufacturing plants and analysed for 40 mycotoxins using high-performance liquid chromatography-high resolution mass spectrometry. Twenty-nine (73%) mycotoxins were identified with 76 (97%) samples testing positive for mycotoxins presence. Mycotoxins with the highest prevalences were enniatin B (91%), deoxynivalenol (76%) and fumonisin B1 (54%) while those with the highest maximum levels were sterigmatocystin (<30.5-3517.1 µg/kg); moniliformin (<218.9-2583.4 µg/kg) and ergotamine (<29.3-1895.6 µg/kg). Mycotoxin co-occurrence was observed in 68 (87%) samples. Correlations were observed between the fumonisins; enniatins B and zearalenone and its metabolites. Fish dietary exposure estimates ranged between <0.16 and 43.38 µg/kg body weight per day. This study shows evidence of mycotoxin presence and co-occurrence in fish feeds and feed ingredients in Kenya. Fish exposure to these levels of mycotoxins over a long period of time may lead to adverse health effects due to their possible additive, synergistic or antagonist toxic effects. Measures to reduce fish feed mycotoxin contamination should be taken to avoid mycotoxicosis in fish and subsequently in humans and animals through residues.


Assuntos
Ração Animal/microbiologia , Peixes , Micotoxinas/análise , Alimentos Marinhos , Animais , Aquicultura , Cromatografia Líquida de Alta Pressão , Microbiologia de Alimentos , Abastecimento de Alimentos , Quênia , Espectrometria de Massas , Micotoxinas/toxicidade , Medição de Risco
10.
Toxins (Basel) ; 10(12)2018 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-30562952

RESUMO

Aflatoxins are fungal metabolites that contaminate foods and feeds, causing adverse health effects in humans and animals. This study determined the occurrence of aflatoxins in fish feeds and their potential effects on fish. Eighty-one fish feeds were sampled from 70 farms and 8 feed manufacturing plants in Nyeri, Kenya for aflatoxin analysis using competitive enzyme-linked immunosorbent assay. Fish were sampled from 12 farms for gross and microscopic pathological examination. Eighty-four percent of feeds sampled tested positive for aflatoxins, ranging from 1.8 to 39.7 µg/kg with a mean of 7.0 ± 8.3 µg/kg and the median of 3.6 µg/kg. Fifteen feeds (18.5%) had aflatoxins above the maximum allowable level in Kenya of 10 µg/kg. Homemade and tilapia feeds had significantly higher aflatoxin levels than commercial and trout feeds. Feeds containing maize bran and fish meal had significantly higher aflatoxin levels than those without these ingredients. Five trout farms (41.7%) had fish with swollen abdomens, and enlarged livers with white or yellow nodules, which microscopically had large dark basophilic hepatic cells with hyperchromatic nuclei in irregular cords. In conclusion, aflatoxin contamination of fish feeds is prevalent in Nyeri, and may be the cause of adverse health effects in fish in this region.


Assuntos
Aflatoxinas/análise , Ração Animal/análise , Contaminação de Alimentos/análise , Aflatoxinas/toxicidade , Ração Animal/efeitos adversos , Animais , Monitoramento Ambiental , Produtos Pesqueiros , Peixes , Quênia , Fígado/efeitos dos fármacos , Fígado/patologia , Zea mays
11.
EFSA J ; 16(5): e05242, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-32625894

RESUMO

Fumonisins, mycotoxins primarily produced by Fusarium verticillioides and Fusarium proliferatum, occur predominantly in cereal grains, especially in maize. The European Commission asked EFSA for a scientific opinion on the risk to animal health related to fumonisins and their modified and hidden forms in feed. Fumonisin B1 (FB 1), FB 2 and FB 3 are the most common forms of fumonisins in feedstuffs and thus were included in the assessment. FB 1, FB 2 and FB 3 have the same mode of action and were considered as having similar toxicological profile and potencies. For fumonisins, the EFSA Panel on Contaminants in the Food Chain (CONTAM) identified no-observed-adverse-effect levels (NOAELs) for cattle, pig, poultry (chicken, ducks and turkeys), horse, and lowest-observed-adverse-effect levels (LOAELs) for fish (extrapolated from carp) and rabbits. No reference points could be identified for sheep, goats, dogs, cats and mink. The dietary exposure was estimated on 18,140 feed samples on FB 1-3 representing most of the feed commodities with potential presence of fumonisins. Samples were collected between 2003 and 2016 from 19 different European countries, but most of them from four Member States. To take into account the possible occurrence of hidden forms, an additional factor of 1.6, derived from the literature, was applied to the occurrence data. Modified forms of fumonisins, for which no data were identified concerning both the occurrence and the toxicity, were not included in the assessment. Based on mean exposure estimates, the risk of adverse health effects of feeds containing FB 1-3 was considered very low for ruminants, low for poultry, horse, rabbits, fish and of potential concern for pigs. The same conclusions apply to the sum of FB 1-3 and their hidden forms, except for pigs for which the risk of adverse health effect was considered of concern.

12.
EFSA J ; 16(3): e05082, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32625822

RESUMO

Moniliformin (MON) is a mycotoxin with low molecular weight primarily produced by Fusarium fungi and occurring predominantly in cereal grains. Following a request of the European Commission, the CONTAM Panel assessed the risk of MON to human and animal health related to its presence in food and feed. The limited information available on toxicity and on toxicokinetics in experimental and farm animals indicated haematotoxicity and cardiotoxicity as major adverse health effects of MON. MON causes chromosome aberrations in vitro but no in vivo genotoxicity data and no carcinogenicity data were identified. Due to the limitations in the available toxicity data, human acute or chronic health-based guidance values (HBGV) could not be established. The margin of exposure (MOE) between the no-observed-adverse-effect level (NOAEL) of 6.0 mg/kg body weight (bw) for cardiotoxicity from a subacute study in rats and the acute upper bound (UB) dietary exposure estimates ranged between 4,000 and 73,000. The MOE between the lowest benchmark dose lower confidence limit (for a 5% response - BMDL05) of 0.20 mg MON/kg bw per day for haematological hazards from a 28-day study in pigs and the chronic dietary human exposure estimates ranged between 370 and 5,000,000 for chronic dietary exposures. These MOEs indicate a low risk for human health but were associated with high uncertainty. The toxicity data available for poultry, pigs, and mink indicated a low or even negligible risk for these animals from exposure to MON in feed at the estimated exposure levels under current feeding practices. Assuming similar or lower sensitivity as for pigs, the CONTAM Panel considered a low or even negligible risk for the other animal species for which no toxicity data suitable for hazard characterisation were identified. Additional toxicity studies are needed and depending on their outcome, the collection of more occurrence data on MON in food and feed is recommended to enable a comprehensive human risk assessment.

13.
EFSA J ; 16(8): e05367, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32626015

RESUMO

4,15-Diacetoxyscirpenol (DAS) is a mycotoxin primarily produced by Fusarium fungi and occurring predominantly in cereal grains. As requested by the European Commission, the EFSA Panel on Contaminants in the Food Chain (CONTAM) assessed the risk of DAS to human and animal health related to its presence in food and feed. Very limited information was available on toxicity and on toxicokinetics in experimental and farm animals. Due to the limitations in the available data set, human acute and chronic health-based guidance values (HBGV) were established based on data obtained in clinical trials of DAS as an anticancer agent (anguidine) after intravenous administration to cancer patients. The CONTAM Panel considered these data as informative for the hazard characterisation of DAS after oral exposure. The main adverse effects after acute and repeated exposure were emesis, with a no-observed-adverse-effect level (NOAEL) of 32 µg DAS/kg body weight (bw), and haematotoxicity, with a NOAEL of 65 µg DAS/kg bw, respectively. An acute reference dose (ARfD) of 3.2 µg DAS/kg bw and a tolerable daily intake (TDI) of 0.65 µg DAS/kg bw were established. Based on over 15,000 occurrence data, the highest acute and chronic dietary exposures were estimated to be 0.8 and 0.49 µg DAS/kg bw per day, respectively, and were not of health concern for humans. The limited information for poultry, pigs and dogs indicated a low risk for these animals at the estimated DAS exposure levels under current feeding practices, with the possible exception of fattening chicken. Assuming similar or lower sensitivity than for poultry, the risk was considered overall low for other farm and companion animal species for which no toxicity data were available. In consideration of the similarities of several trichothecenes and the likelihood of co-exposure via food and feed, it could be appropriate to perform a cumulative risk assessment for this group of substances.

14.
Toxins (Basel) ; 9(2)2017 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-28165414

RESUMO

Deoxynivalenol (DON) is the most common mycotoxin in Norwegian cereals, and DON is detected in most samples of crude cereal grain and cereal food commodities such as flour, bran, and oat flakes. The Norwegian Scientific Committee for Food Safety assessed the risk for adverse effects of deoxynivalenol (DON) in different age groups of the domestic population. This review presents the main results from the risk assessment, supplemented with some recently published data. Impairment of the immune system together with reduced feed intake and weight gain are the critical effects of DON in experimental animals on which the current tolerable daily intake was established. Based on food consumption and occurrence data, the mean exposure to DON in years with low and high levels of DON in the flour, respectively, were in the range of or up to two times the Tolerable Daily Intake (TDI) in 1-year-old infants and 2-year-old children. In years with high mean DON concentration, the high (95th-percentile) exposure exceeded the TDI by up to 3.5 times in 1-, 2- , 4-, and 9-year-old children. The assessment concluded that exceeding the TDI in infants and children is of concern. The estimated dietary DON intakes in adolescent and adult populations are in the range of the TDI or below, and are not a health concern. Acute human exposure to DON is not of concern in any age group.


Assuntos
Dieta/efeitos adversos , Grão Comestível/efeitos adversos , Grão Comestível/microbiologia , Exposição Ambiental/efeitos adversos , Microbiologia de Alimentos , Fusarium/metabolismo , Tricotecenos/efeitos adversos , Adolescente , Adulto , Distribuição por Idade , Idoso , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Nível de Efeito Adverso não Observado , Noruega , Medição de Risco , Fatores de Risco , Fatores de Tempo , Tricotecenos/metabolismo , Adulto Jovem
15.
J Hazard Mater ; 337: 80-89, 2017 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-28511044

RESUMO

Bentonites are commonly used as feed additives to reduce the bioavailability and thus the toxicity of aflatoxins by adsorbing the toxins in the gastrointestinal tract. Aflatoxins are particular harmful mycotoxins mainly found in areas with hot and humid climates. They occur in food and feedstuff as a result of fungal contamination before and after harvest. The aim of this study was to modify Brazilian bentonite clay by incorporation of zinc (Zn) ions in order to increase the adsorption capacity and consequently reduce the toxicity of aflatoxins. The significance of Zn intercalating conditions such as concentration, temperature and reaction time were investigated. Our results showed that the Zn treatment of the bentonite increased the aflatoxin B1 (AFB1) adsorption and that Zn concentration had a negative effect. Indeed, temperature and time had no significant effect in the binding capacity. The modified bentonite (Zn-Bent1) was not cytotoxic to either fibroblasts (3T3) nor epithelial colorectal adenocarcinoma cells (Caco-2) cell lines. Interestingly, Zn-Bent1 has higher protective effect against AFB1 induced cytotoxicity than the unmodified bentonite. In conclusion, the Zn modified bentonite, Zn-Bent1, represent an improved tool to prevent aflatoxicosis in animals fed on AFB1 contaminated feed.


Assuntos
Aflatoxina B1/isolamento & purificação , Aflatoxina B1/intoxicação , Bentonita/farmacologia , Zinco/química , Células 3T3 , Adsorção , Aflatoxina B1/química , Ração Animal/análise , Animais , Bentonita/química , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Contaminação de Alimentos/análise , Humanos , Camundongos , Microscopia Eletrônica de Varredura , Intoxicação/prevenção & controle , Intoxicação/veterinária , Espectroscopia de Infravermelho com Transformada de Fourier
16.
Artigo em Inglês | MEDLINE | ID: mdl-28490257

RESUMO

Post-smolt Atlantic salmon (Salmo salar) were fed standard feed with added 2 or 6 mg kg-1 pure deoxynivalenol (DON), 0.8 or 2.4 mg kg-1 pure ochratoxin A (OTA), or no added toxins for up to 8 weeks. The experiments were performed in duplicate tanks with 25 fish each per diet group, and the feed was given for three 2-h periods per day. After 3, 6 and 8 weeks, 10 fish from each diet group were sampled. In the following hours after the last feeding at 8 weeks, toxin elimination was studied by sampling three fish per diet group at five time points. Analysis of DON and OTA in fish tissues and plasma was conducted by liquid chromatography-mass spectrometry and high-pressure liquid chromatography with fluorescence detection, respectively. DON was distributed to the liver, kidney, plasma, muscle, skin and brain, and the concentrations in liver and muscle increased significantly from 3 to 8 weeks of exposure to the high-DON diet. After the last feeding at 8 weeks, DON concentration in liver reached a maximum at 1 h and decreased thereafter with a half-life (t1/2) of 6.2 h. DON concentration in muscle reached a maximum at 6 h and was then eliminated with a t1/2 = 16.5 h. OTA was mainly found in liver and kidney, and the concentration in liver decreased significantly from 3 to 8 weeks in the high-OTA group. OTA was eliminated faster than DON from various tissues. By using Norwegian food consumption data and kinetic findings in this study, we predicted the human exposure to DON and OTA from fish products through carryover from the feed. Following a comparison with tolerable daily intakes, we found the risk to human health from the consumption of salmon-fed diets containing maximum recommended levels of these toxins to be negligible.


Assuntos
Ração Animal/análise , Dieta/veterinária , Contaminação de Alimentos/análise , Ocratoxinas/farmacocinética , Salmo salar/metabolismo , Tricotecenos/farmacocinética , Adulto , Animais , Pré-Escolar , Cromatografia Líquida , Humanos , Espectrometria de Massas , Ocratoxinas/administração & dosagem , Ocratoxinas/análise , Distribuição Tecidual , Tricotecenos/administração & dosagem , Tricotecenos/análise
17.
EFSA J ; 15(7): e04851, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32625539

RESUMO

Zearalenone (ZEN), a mycotoxin primarily produced by Fusarium fungi, occurs predominantly in cereal grains. The European Commission asked EFSA for a scientific opinion on the risk to animal health related to ZEN and its modified forms in feed. Modified forms of ZEN occurring in feed include phase I metabolites α-zearalenol (α-ZEL), ß-zearalenol (ß-ZEL), α-zearalanol (α-ZAL), ß-zearalanol (ß-ZAL), zearalanone (ZAN) and phase II conjugates. ZEN has oestrogenic activity and the oestrogenic activity of the modified forms of ZEN differs considerably. For ZEN, the EFSA Panel on Contaminants in the Food Chain (CONTAM) established no observed adverse effect levels (NOAELs) for pig (piglets and gilts), poultry (chicken and fattening turkeys), sheep and fish (extrapolated from carp) and lowest observed effect level (LOAEL) for dogs. No reference points could be established for cattle, ducks, goats, horses, rabbits, mink and cats. For modified forms, no reference points could be established for any animal species and relative potency factors previously established from rodents by the CONTAM Panel in 2016 were used. The dietary exposure was estimated on 17,706 analytical results with high proportions of left-censored data (ZEN about 60%, ZAN about 70%, others close to 100%). Samples for ZEN were collected between 2001 and 2015 in 25 different European countries, whereas samples for the modified forms were collected mostly between 2013 and 2015 from three Member States. Based on exposure estimates, the risk of adverse health effects of feed containing ZEN was considered extremely low for poultry and low for sheep, dog, pig and fish. The same conclusions also apply to the sum of ZEN and its modified forms.

18.
EFSA J ; 15(9): e04718, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32625635

RESUMO

Deoxynivalenol (DON) is a mycotoxin primarily produced by Fusarium fungi, occurring predominantly in cereal grains. Following the request of the European Commission, the CONTAM Panel assessed the risk to animal and human health related to DON, 3-acetyl-DON (3-Ac-DON), 15-acetyl-DON (15-Ac-DON) and DON-3-glucoside in food and feed. A total of 27,537, 13,892, 7,270 and 2,266 analytical data for DON, 3-Ac-DON, 15-Ac-DON and DON-3-glucoside, respectively, in food, feed and unprocessed grains collected from 2007 to 2014 were used. For human exposure, grains and grain-based products were main sources, whereas in farm and companion animals, cereal grains, cereal by-products and forage maize contributed most. DON is rapidly absorbed, distributed, and excreted. Since 3-Ac-DON and 15-Ac-DON are largely deacetylated and DON-3-glucoside cleaved in the intestines the same toxic effects as DON can be expected. The TDI of 1 µg/kg bw per day, that was established for DON based on reduced body weight gain in mice, was therefore used as a group-TDI for the sum of DON, 3-Ac-DON, 15-Ac-DON and DON-3-glucoside. In order to assess acute human health risk, epidemiological data from mycotoxicoses were assessed and a group-ARfD of 8 µg/kg bw per eating occasion was calculated. Estimates of acute dietary exposures were below this dose and did not raise a health concern in humans. The estimated mean chronic dietary exposure was above the group-TDI in infants, toddlers and other children, and at high exposure also in adolescents and adults, indicating a potential health concern. Based on estimated mean dietary concentrations in ruminants, poultry, rabbits, dogs and cats, most farmed fish species and horses, adverse effects are not expected. At the high dietary concentrations, there is a potential risk for chronic adverse effects in pigs and fish and for acute adverse effects in cats and farmed mink.

19.
Toxins (Basel) ; 5(10): 1682-97, 2013 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-24084167

RESUMO

Recent climatological research predicts a significantly wetter climate in Southern Norway as a result of global warming. Thus, the country has already experienced unusually wet summer seasons in the last three years (2010-2012). The aim of this pilot study was to apply an existing multi-analyte LC-MS/MS method for the semi-quantitative determination of 320 fungal and bacterial metabolites in Norwegian cereal grain samples from the 2011 growing season. Such knowledge could provide important information for future survey and research programmes in Norway. The method includes all regulated and well-known mycotoxins such as aflatoxins, trichothecenes, ochratoxin A, fumonisins and zearalenone. In addition, a wide range of less studied compounds are included in the method, e.g., Alternaria toxins, ergot alkaloids and other metabolites produced by fungal species within Fusarium, Penicillium and Aspergillus. Altogether, 46 metabolites, all of fungal origin, were detected in the 76 barley, oats and wheat samples. The analyses confirmed the high prevalence and relatively high concentrations of type-A and -B trichothecenes (e.g., deoxynivalenol up to 7230 µg/kg, HT-2 toxin up to 333 µg/kg). Zearalenone was also among the major mycotoxins detected (maximum concentration 1670 µg/kg). Notably, several other Fusarium metabolites such as culmorin, 2-amino-14,16-dimethyloctadecan-3-ol and avenacein Y were co-occurring. Furthermore, the most prevalent Alternaria toxin was alternariol with a maximum concentration of 449 µg/kg. A number of Penicillium and Aspergillus metabolites were also detected in the samples, e.g., sterigmatocystin in concentrations up to 20 µg/kg.


Assuntos
Grão Comestível/química , Contaminação de Alimentos/análise , Micotoxinas/análise , Alternaria/metabolismo , Aspergillus/metabolismo , Mudança Climática , Monitoramento Ambiental , Alcaloides de Claviceps/análise , Fusarium/metabolismo , Noruega , Penicillium/metabolismo
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