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Sample records for reducing aflatoxin exposure

  1. Workgroup Report: Public Health Strategies for Reducing Aflatoxin Exposure in Developing Countries

    PubMed Central

    Strosnider, Heather; Azziz-Baumgartner, Eduardo; Banziger, Marianne; Bhat, Ramesh V.; Breiman, Robert; Brune, Marie-Noel; DeCock, Kevin; Dilley, Abby; Groopman, John; Hell, Kerstin; Henry, Sara H.; Jeffers, Daniel; Jolly, Curtis; Jolly, Pauline; Kibata, Gilbert N.; Lewis, Lauren; Liu, Xiumei; Luber, George; McCoy, Leslie; Mensah, Patience; Miraglia, Marina; Misore, Ambrose; Njapau, Henry; Ong, Choon-Nam; Onsongo, Mary T.K.; Page, Samuel W.; Park, Douglas; Patel, Manish; Phillips, Timothy; Pineiro, Maya; Pronczuk, Jenny; Rogers, Helen Schurz; Rubin, Carol; Sabino, Myrna; Schaafsma, Arthur; Shephard, Gordon; Stroka, Joerg; Wild, Christopher; Williams, Jonathan T.; Wilson, David

    2006-01-01

    Consecutive outbreaks of acute aflatoxicosis in Kenya in 2004 and 2005 caused > 150 deaths. In response, the Centers for Disease Control and Prevention and the World Health Organization convened a workgroup of international experts and health officials in Geneva, Switzerland, in July 2005. After discussions concerning what is known about aflatoxins, the workgroup identified gaps in current knowledge about acute and chronic human health effects of aflatoxins, surveillance and food monitoring, analytic methods, and the efficacy of intervention strategies. The workgroup also identified public health strategies that could be integrated with current agricultural approaches to resolve gaps in current knowledge and ultimately reduce morbidity and mortality associated with the consumption of aflatoxin-contaminated food in the developing world. Four issues that warrant immediate attention were identified: a) quantify the human health impacts and the burden of disease due to aflatoxin exposure; b) compile an inventory, evaluate the efficacy, and disseminate results of ongoing intervention strategies; c) develop and augment the disease surveillance, food monitoring, laboratory, and public health response capacity of affected regions; and d) develop a response protocol that can be used in the event of an outbreak of acute aflatoxicosis. This report expands on the workgroup’s discussions concerning aflatoxin in developing countries and summarizes the findings. PMID:17185282

  2. Reduced aflatoxin exposure presages decline in liver cancer mortality in an endemic region of China.

    PubMed

    Chen, Jian-Guo; Egner, Patricia A; Ng, Derek; Jacobson, Lisa P; Muñoz, Alvaro; Zhu, Yuan-Rong; Qian, Geng-Sun; Wu, Felicia; Yuan, Jian-Min; Groopman, John D; Kensler, Thomas W

    2013-10-01

    Primary liver cancer (PLC) is the third leading cause of cancer mortality globally. In endemic areas of sub-Saharan Africa and Asia, PLC largely arises from chronic infection with hepatitis B virus (HBV) and ingestion of aflatoxins. Although synergistic interactions between these two risk factors have been observed in cohort studies in China, here we determined the impact of agricultural reforms in the 1980s leading to diminished maize consumption and implementation of subsidized universal vaccination against HBV in the 2000s on PLC primary prevention. A population-based cancer registry was used to track PLC mortality in Qidong, China and was compared with the timeline of HBV immunization. Randomly selected serum samples from archived cohort collections from the 1980s to present were analyzed for aflatoxin biomarkers. More than 50% reductions in PLC mortality rates occurred across birth cohorts from the 1960s to the 1980s for Qidongese less than 35 years of age although all were born before universal vaccination of newborns. Median levels of the aflatoxin biomarker decreased from 19.3 pg/mg albumin in 1989 to undetectable (<0.5 pg/mg) by 2009. A population attributable benefit of 65% for reduced PLC mortality was estimated from a government-facilitated switch of dietary staple from maize to rice; 83% of this benefit was in those infected with HBV. Food policy reforms in China resulted in a dramatic decrease in aflatoxin exposure, which, independent of HBV vaccination, reduced liver cancer risk. The extensive HBV vaccine coverage now in place augurs even greater risk reductions in the future.

  3. Reduced Aflatoxin Exposure Presages Decline in Liver Cancer Mortality in an Endemic Region of China

    PubMed Central

    Chen, Jian-Guo; Egner, Patricia A.; Ng, Derek; Jacobson, Lisa P.; Muñoz, Alvaro; Zhu, Yuan-Rong; Qian, Geng-Sun; Wu, Felicia; Yuan, Jian-Min; Groopman, John D.; Kensler, Thomas W.

    2013-01-01

    Primary liver cancer (PLC) is the third leading cause of cancer mortality globally. In endemic areas of sub-Saharan Africa and Asia PLC largely arises from chronic infection with hepatitis B virus (HBV) and ingestion of aflatoxins. While synergistic interactions between these two risk factors have been observed in cohort studies in China, here we determined the impact of agricultural reforms in the 1980s leading to diminished maize consumption and implementation of subsidized universal vaccination against HBV in the 2000s on PLC primary prevention. A population-based cancer registry was used to track PLC mortality in Qidong, China and was compared to the timeline of HBV immunization. Randomly selected serum samples from archived cohort collections from the 1980s to present were analyzed for aflatoxin biomarkers. Greater than 50% reductions in PLC mortality rates occurred across birth cohorts from the 1960s to the 1980s for Qidongese less than 35 years of age although all were born before universal vaccination of newborns. Median levels of the aflatoxin biomarker decreased from 19.3 pg/mg albumin in 1989 to undetectable (<0.5 pg/mg) by 2009. A population attributable benefit of 65% for reduced PLC mortality was estimated from a government facilitated switch of dietary staple from maize to rice; 83% of this benefit was in those infected with HBV. Food policy reforms in China resulted in a dramatic decrease in aflatoxin exposure, which, independent of HBV vaccination, reduced liver cancer risk. The extensive HBV vaccine coverage now in place augurs even greater risk reductions in the future. PMID:23963804

  4. Reduction in the urinary aflatoxin M1 biomarker as an early indicator of the efficacy of dietary interventions to reduce exposure to aflatoxins.

    PubMed

    Mitchell, Nicole J; Kumi, Justice; Johnson, Natalie M; Dotse, Eunice; Marroquin-Cardona, Alicia; Wang, Jia-Sheng; Jolly, Pauline E; Ankrah, Nii-Ayi; Phillips, Timothy D

    2013-08-01

    Aflatoxin B1 is a persistent public health issue in Ghana. Assessment of AFB1 intervention efficacy is currently dependent on long-term biomarkers. This study was designed to determine whether daily AFM1 biomarker levels could be utilized as an early detection method for intervention efficacy. Participants were treated with a refined calcium montmorillonite clay (UPSN) or a placebo (calcium carbonate) in a crossover study. Urine samples were assessed for AFM1 levels daily. UPSN treatment reduced AFM1 biomarkers by 55% compared to the placebo. This is the first study to show that daily urinary AFM1 levels can be used as a biomarker of internal aflatoxin B1 exposure in short-term intervention trials to determine efficacy.

  5. Fungal Aflatoxins Reduce Respiratory Mucosal Ciliary Function

    PubMed Central

    Lee, Robert J.; Workman, Alan D.; Carey, Ryan M.; Chen, Bei; Rosen, Phillip L.; Doghramji, Laurel; Adappa, Nithin D.; Palmer, James N.; Kennedy, David W.; Cohen, Noam A.

    2016-01-01

    Aflatoxins are mycotoxins secreted by Aspergillus flavus, which can colonize the respiratory tract and cause fungal rhinosinusitis or bronchopulmonary aspergillosis. A. flavus is the second leading cause of invasive aspergillosis worldwide. Because many respiratory pathogens secrete toxins to impair mucociliary immunity, we examined the effects of acute exposure to aflatoxins on airway cell physiology. Using air-liquid interface cultures of primary human sinonasal and bronchial cells, we imaged ciliary beat frequency (CBF), intracellular calcium, and nitric oxide (NO). Exposure to aflatoxins (0.1 to 10 μM; 5 to 10 minutes) reduced baseline (~6–12%) and agonist-stimulated CBF. Conditioned media (CM) from A. fumigatus, A. niger, and A. flavus cultures also reduced CBF by ~10% after 60 min exposure, but effects were blocked by an anti-aflatoxin antibody only with A. flavus CM. CBF reduction required protein kinase C but was not associated with changes in calcium or NO. However, AFB2 reduced NO production by ~50% during stimulation of the ciliary-localized T2R38 receptor. Using a fluorescent reporter construct expressed in A549 cells, we directly observed activation of PKC activity by AFB2. Aflatoxins secreted by respiratory A. flavus may impair motile and chemosensory functions of airway cilia, contributing to pathogenesis of fungal airway diseases. PMID:27623953

  6. Dietary aflatoxin exposure and chemoprevention of cancer: a clinical review.

    PubMed

    Sudakin, Daniel L

    2003-01-01

    Exposure to dietary aflatoxins is considered to be an important risk factor for the development of hepatocellular carcinoma in certain regions of the world. Significant advances have recently been made in understanding the clinical toxicology of aflatoxins. These include the development and validation of biomarkers of exposure and genotoxic effect. These biomarkers are currently being utilized to explore the potential that pharmaceutical interventions may have in modifying the toxicokinetics of dietary aflatoxin exposure. Preliminary results of clinical trials with the drug oltipraz suggest that it may modify the genotoxic effects of aflatoxin B1 by inhibiting bioactivation pathways and stimulating detoxification pathways. More recent results of a clinical trial with chlorophyllin suggest that this drug may have a role in preventing dietary exposure to aflatoxin B1 by reducing its oral bioavailability. The preliminary results of these chemoprevention studies may ultimately have implications for cancer prevention in high-risk populations in the future.

  7. Evaluation of the efficacy, acceptability and palatability of calcium montmorillonite clay used to reduce aflatoxin B1 dietary exposure in a crossover study in Kenya.

    PubMed

    Awuor, Abigael O; Yard, Ellen; Daniel, Johnni H; Martin, Collen; Bii, Christine; Romoser, Amelia; Oyugi, Elvis; Elmore, Sarah; Amwayi, Samwel; Vulule, John; Zitomer, Nicholas C; Rybak, Michael E; Phillips, Timothy D; Montgomery, Joel M; Lewis, Lauren S

    2017-01-01

    Acute aflatoxin exposure can cause death and disease (aflatoxicosis) in humans. Aflatoxicosis fatality rates have been documented to be as high as 40% in Kenya. The inclusion in the diet of calcium silicate 100 (ACCS100), a calcium montmorillonite clay, may reduce aflatoxin bioavailability, thus potentially decreasing the risk of aflatoxicosis. We investigated the efficacy, acceptability and palatability of ACCS100 in a population in Kenya with recurring aflatoxicosis outbreaks. Healthy adult participants were enrolled in this double-blinded, crossover clinical trial in 2014. Following informed consent, participants (n = 50) were randomised to receive either ACCS100 (3 g day(-1)) or placebo (3 g day(-1)) for 7 days. Treatments were switched following a 5-day washout period. Urine samples were collected daily and assessed for urinary aflatoxin M1 (AFM1). Blood samples were collected at the beginning and end of the trial and assessed for aflatoxin B1-lysine adducts from serum albumin (AFB1-lys). AFM1 concentrations in urine were significantly reduced while taking ACCS100 compared with calcium carbonate placebo (β = 0.49, 95% confidence limit = 0.32-0.75). The 20-day interval included both the placebo and ACCS100 treatments as well as a washout period. There were no statistically significant differences in reported taste, aftertaste, appearance, colour or texture by treatment. There were no statistically significant differences in self-reported adverse events by treatment. Most participants would be willing to take ACCS100 (98%) and give it to their children (98%). ACCS100 was effective, acceptable and palatable. More work is needed to test ACCS100 among vulnerable populations and to determine if it remains effective at the levels of aflatoxin exposure that induce aflatoxicosis.

  8. Exposure measurement of aflatoxins and aflatoxin metabolites in human body fluids. A short review.

    PubMed

    Leong, Yin-Hui; Latiff, Aishah A; Ahmad, Nurul Izzah; Rosma, Ahmad

    2012-05-01

    Aflatoxins are highly toxic secondary fungal metabolites mainly produced by Aspergillus flavus and A. parasiticus. Human exposure to aflatoxins may result directly from ingestion of contaminated foods, or indirectly from consumption of foods from animals previously exposed to aflatoxins in feeds. This paper focuses on exposure measurement of aflatoxins and aflatoxin metabolites in various human body fluids. Research on different metabolites present in blood, urine, breast milk, and other human fluids or tissues including their detection techniques is reviewed. The association between dietary intake of aflatoxins and biomarker measurement is also highlighted. Finally, aspects related to the differences between aflatoxin determination in food versus the biomarker approach are discussed.

  9. Calcium montmorillonite clay reduces AFB1 and FB1 biomarkers in rats exposed to single and co-exposures of aflatoxin and fumonisin.

    PubMed

    Mitchell, Nicole J; Xue, Kathy S; Lin, Shuhan; Marroquin-Cardona, Alicia; Brown, Kristal A; Elmore, Sarah E; Tang, Lili; Romoser, Amelia; Gelderblom, Wentzel C A; Wang, Jia-Sheng; Phillips, Timothy D

    2014-07-01

    Aflatoxins (AFs) and fumonisins (FBs) can co-contaminate foodstuffs and have been associated with hepatocellular and esophageal carcinomas in humans at high risk for exposure. One strategy to reduce exposure (and toxicity) from contaminated foodstuffs is the dietary inclusion of a montmorillonite clay (UPSN) that binds AFs and FBs in the gastrointestinal tract. In this study, the binding capacity of UPSN was evaluated for AFB1, FB1 and a combination thereof in Fischer 344 rats. Rats were pre-treated with different dietary levels of UPSN (0.25% or 2%) for 1 week. Rats were gavaged with a single dose of either 0.125 mg AFB1 or 25 mg FB1 per kg body weight and a combination thereof in the presence and absence of an aqueous solution of UPSN. The kinetics of mycotoxin excretion were monitored by analyzing serum AFB1 -albumin, urinary AF (AFM1) and FB1 biomarkers over a period of 72 h. UPSN decreased AFM1 excretion by 88-97%, indicating highly effective binding. FB1 excretion was reduced, to a lesser extent, ranging from 45% to 85%. When in combination, both AFB1 and FB1 binding occurred, but capacity was decreased by almost half. In the absence of UPSN, the combined AFB1 and FB1 treatment decreased the urinary biomarkers by 67% and 45% respectively, but increased levels of AFB1 -albumin, presumably by modulating its cytochrome metabolism. UPSN significantly reduced bioavailability of both AFB1 and FB1 when in combination; suggesting that it can be utilized to reduce levels below their respective thresholds for affecting adverse biological effects. Copyright © 2013 John Wiley & Sons, Ltd.

  10. Calcium montmorillonite clay reduces AFB1 and FB1 biomarkers in rats exposed to single and co-exposures of aflatoxin and fumonisin

    PubMed Central

    Mitchell, Nicole J.; Xue, Kathy S.; Lin, Shuhan; Marroquin-Cardona, Alicia; Brown, Kristal A.; Elmore, Sarah E.; Tang, Lili; Romoser, Amelia; Gelderblom, Wentzel C. A.; Wang, Jia-Sheng; Phillips, Timothy D.

    2014-01-01

    Aflatoxins (AFs) and fumonisins (FBs) can co-contaminate foodstuffs and have been associated with hepatocellular and esophageal carcinomas in humans at high risk for exposure. One strategy to reduce exposure (and toxicity) from contaminated foodstuffs is the dietary inclusion of a montmorillonite clay (UPSN) that binds AFs and FBs in the GI tract. In this study, the binding capacity of UPSN was evaluated for AFB1, FB1 and a combination thereof in Fischer-344 rats. Rats were pre-treated with different dietary levels of UPSN (0.25 or 2%) for 1 week. Rats were gavaged with a single dose of either 0.125 mg AFB1 or 25 mg FB1/kg b.w. and a combination thereof in the presence and absence of an aqueous solution of UPSN. The kinetics of mycotoxin excretion were monitored by analyzing serum AFB1-albumin, urinary AF (AFM1), and FB1 biomarkers over a period of 72 hr. UPSN decreased AFM1 excretion by 88-97%, indicating highly effective binding. FB1 excretion was reduced, to a lesser extent, ranging between 45 to 85%. When in combination, both AFB1 and FB1 binding occurred, but capacity was decreased by almost half. In the absence of UPSN, the combined AFB1 and FB1 treatment decreased the urinary biomarkers by 67 and 45% respectively, but increased levels of AFB1-albumin, presumably by modulating its cytochrome metabolism. UPSN significantly reduced bioavailability of both AFB1 and FB1 when in combination; suggesting that it can be utilized to reduce levels below their respective thresholds for affecting adverse biological effects. PMID:24193864

  11. Interventions targeting child undernutrition in developing countries may be undermined by dietary exposure to aflatoxin.

    PubMed

    Watson, Sinead; Gong, Yun Yun; Routledge, Michael

    2017-06-13

    Child undernutrition, a form of malnutrition, is a major public health burden in developing countries. Supplementation interventions targeting the major micronutrient deficiencies have only reduced the burden of child undernutrition to a certain extent, indicating that there are other underlying determinants that need to be addressed. Aflatoxin exposure, which is also highly prevalent in developing countries, may be considered an aggravating factor for child undernutrition. Increasing evidence suggests that aflatoxin exposure can occur in any stage of life, including in utero through a trans-placental pathway and in early childhood (through contaminated weaning food and family food). Early life exposure to aflatoxin is associated with adverse effects on low birth weight, stunting, immune suppression, and the liver function damage. The mechanisms underlying impaired growth and aflatoxin exposure are still unclear but intestinal function damage, reduced immune function, and alteration in the insulin-like growth factor axis caused by the liver damage are the suggested hypotheses. Given the fact that both aflatoxin and child undernutrition are common in sub-Saharan Africa, effective interventions aimed at reducing undernutrition cannot be satisfactorily achieved until the interactive relationship between aflatoxin and child undernutrition is clearly understood, and an aflatoxin mitigation strategy takes effect in those vulnerable mothers and children.

  12. Breast cancer resistance protein (Bcrp1/Abcg2) reduces systemic exposure of the dietary carcinogens aflatoxin B1, IQ and Trp-P-1 but also mediates their secretion into breast milk.

    PubMed

    van Herwaarden, Antonius E; Wagenaar, Els; Karnekamp, Barbara; Merino, Gracia; Jonker, Johan W; Schinkel, Alfred H

    2006-01-01

    The breast cancer resistance protein (BCRP/ABCG2) usually protects the body from a wide variety of environmental and dietary xenotoxins by reducing their net uptake from intestine and by increasing their hepatobiliary, intestinal and renal elimination. BCRP is also highly expressed in lactating mammary glands in mice, and this expression is conserved in cows and humans. As a result, BCRP substrates can be secreted into milk. We investigated whether different classes of dietary carcinogens are substrates of Bcrp1/BCRP and the implications for systemic exposure and breast milk contamination. Using polarized cell lines, we found that Bcrp1 transports the heterocyclic amines 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) and 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1) and the potent human hepatocarcinogen aflatoxin B1, and decreases their cellular accumulation up to 10-fold. In vivo pharmacokinetic studies showed that [14C]IQ, [14C]Trp-P-1 and [3H]aflatoxin B1 plasma levels were substantially lower in wild-type compared with Bcrp1-/- mice, after both oral and intravenous administration, demonstrating that Bcrp1 restricts systemic exposure to these carcinogens. Moreover, Bcrp1 mediates transfer of [14C]IQ, [14C]Trp-P-1 and [3H]aflatoxin into milk, with 3.4+/-0.6, 2.6+/-0.3 and 3.8+/-0.5-fold higher milk to plasma ratios, respectively, in lactating wild-type versus Bcrp1-/- mice. We have thus identified Bcrp1/BCRP as one of the molecular mechanisms by which heterocyclic amines and aflatoxin are transferred into milk, thereby posing a health risk to breast-fed infants and dairy consumers. Paradoxically, Bcrp1/BCRP appears to have both protective and adverse roles with respect to exposure to dietary carcinogens.

  13. Phytochemicals reduce aflatoxin-induced toxicity in chicken embryos

    USDA-ARS?s Scientific Manuscript database

    Aflatoxins (AF) are toxic metabolites produced by molds, Aspergillus flavus and Aspergillus parasicitus, which frequently contaminate chicken feed ingredients. Ingestion of AF-contaminated feed by chickens leads to deleterious effects, including decreased chicken performance and reduced egg producti...

  14. Aflatoxin biosynthesis: current frontiers.

    PubMed

    Roze, Ludmila V; Hong, Sung-Yong; Linz, John E

    2013-01-01

    Aflatoxins are among the principal mycotoxins that contaminate economically important food and feed crops. Aflatoxin B1 is the most potent naturally occurring carcinogen known and is also an immunosuppressant. Occurrence of aflatoxins in crops has vast economic and human health impacts worldwide. Thus, the study of aflatoxin biosynthesis has become a focal point in attempts to reduce human exposure to aflatoxins. This review highlights recent advances in the field of aflatoxin biosynthesis and explores the functional connection between aflatoxin biosynthesis, endomembrane trafficking, and response to oxidative stress. Dissection of the regulatory mechanisms involves a complete comprehension of the aflatoxin biosynthetic process and the dynamic network of transcription factors that orchestrates coordinated expression of the target genes. Despite advancements in the field, development of a safe and effective multifaceted approach to solve the aflatoxin food contamination problem is still required.

  15. Influences of Climate on Aflatoxin Producing Fungi and Aflatoxin Contamination

    USDA-ARS?s Scientific Manuscript database

    Aflatoxins are potent mycotoxins that cause developmental and immune system suppression, cancer, and death. As a result of regulations intended to reduce human exposure, crop contamination with aflatoxins causes significant economic loss for producers, marketers, and processors of diverse susceptibl...

  16. Aflatoxin exposure in utero causes growth faltering in Gambian infants.

    PubMed

    Turner, Paul C; Collinson, Andrew C; Cheung, Yin Bun; Gong, Yunyun; Hall, Andrew J; Prentice, Andrew M; Wild, Christopher P

    2007-10-01

    Growth faltering in West African children has previously been associated with dietary exposure to aflatoxins, particularly upon weaning. However, in animal studies in utero exposure to low levels of aflatoxin also results in growth faltering. This study investigated the effect of in utero aflatoxin exposure on infant growth in the first year of life in The Gambia. Height and weight were measured for 138 infants at birth and at regular monthly intervals for one year. Aflatoxin-albumin (AF-alb) adduct level was measured in maternal blood during pregnancy, in cord blood and in infants at age 16 weeks. The geometric mean AF-alb levels were 40.4 pg/mg (range 4.8-260.8 pg/mg), 10.1 pg/mg (range 5.0-189.6 pg/mg) and 8.7 pg/mg (range 5.0-30.2 pg/mg) in maternal, cord and infant blood, respectively. AF-alb in maternal blood was a strong predictor of both weight (P = 0.012) and height (P = 0.044) gain, with lower gain in those with higher exposure. A reduction of maternal AF-alb from 110 pg/mg to 10 pg/mg would lead to a 0.8 kg increase in weight and 2 cm increase in height within the first year of life. This study shows a strong effect of maternal aflatoxin exposure during pregnancy on growth in the first year of life and thus extends earlier observations of an association between aflatoxin exposure during infancy and growth faltering. The findings imply value in targeting intervention strategies at early life exposures.

  17. Aflatoxins

    USDA-ARS?s Scientific Manuscript database

    Aflatoxins are toxic and carcinogenic secondary metabolites produced primarily by the filamentous fungi, Aspergillus flavus and Aspergillus parasiticus. Aflatoxin biosynthesis is a quite complex process involving many intermediates and enzymes, regulated at multi-levels. Scientists from biochemist...

  18. The Use of Feed Additives to Reduce the Effects of Aflatoxin and Deoxynivalenol on Pig Growth, Organ Health and Immune Status during Chronic Exposure

    PubMed Central

    Weaver, Alexandra C.; See, M. Todd; Hansen, Jeff A.; Kim, Yong B.; De Souza, Anna L. P.; Middleton, Tina F.; Kim, Sung Woo

    2013-01-01

    Three feed additives were tested to improve the growth and health of pigs chronically challenged with aflatoxin (AF) and deoxynivalenol (DON). Gilts (n = 225, 8.8 ± 0.4 kg) were allotted to five treatments: CON (uncontaminated control); MT (contaminated with 150 µg/kg AF and 1100 µg/kg DON); A (MT + a clay additive); B (MT + a clay and dried yeast additive); and C (MT + a clay and yeast culture additive). Average daily gain (ADG) and feed intake (ADFI) were recorded for 42 days, blood collected for immune analysis and tissue samples to measure damage. Feeding mycotoxins tended to decrease ADG and altered the immune system through a tendency to increase monocytes and immunoglobulins. Mycotoxins caused tissue damage in the form of liver bile ductule hyperplasia and karyomegaly. The additives in diets A and B reduced mycotoxin effects on the immune system and the liver and showed some ability to improve growth. The diet C additive played a role in reducing liver damage. Collectively, we conclude that AF and DON can be harmful to the growth and health of pigs consuming mycotoxins chronically. The selected feed additives improved pig health and may play a role in pig growth. PMID:23867763

  19. The use of feed additives to reduce the effects of aflatoxin and deoxynivalenol on pig growth, organ health and immune status during chronic exposure.

    PubMed

    Weaver, Alexandra C; See, M Todd; Hansen, Jeff A; Kim, Yong B; De Souza, Anna L P; Middleton, Teena F; Kim, Sung Woo

    2013-07-17

    Three feed additives were tested to improve the growth and health of pigs chronically challenged with aflatoxin (AF) and deoxynivalenol (DON). Gilts (n = 225, 8.8 ± 0.4 kg) were allotted to five treatments: CON (uncontaminated control); MT (contaminated with 150 µg/kg AF and 1100 µg/kg DON); A (MT + a clay additive); B (MT + a clay and dried yeast additive); and C (MT + a clay and yeast culture additive). Average daily gain (ADG) and feed intake (ADFI) were recorded for 42 days, blood collected for immune analysis and tissue samples to measure damage. Feeding mycotoxins tended to decrease ADG and altered the immune system through a tendency to increase monocytes and immunoglobulins. Mycotoxins caused tissue damage in the form of liver bile ductule hyperplasia and karyomegaly. The additives in diets A and B reduced mycotoxin effects on the immune system and the liver and showed some ability to improve growth. The diet C additive played a role in reducing liver damage. Collectively, we conclude that AF and DON can be harmful to the growth and health of pigs consuming mycotoxins chronically. The selected feed additives improved pig health and may play a role in pig growth.

  20. [Exposure assessment of liver cancer attributed to dietary aflatoxins exposure in Chinese residents].

    PubMed

    Wang, Jun; Liu, Xiu-Mei; Zhang, Zhi-Qiang

    2009-06-01

    To evaluate the risk of liver cancer attributed to dietary aflatoxins exposure in Chinese residents. Mathematics model and "Margin of Exposure (MOE)" methods were employed in this study. The data used in mathematics model came from Joint FAO/WHO Expert Committee on Food Additives (JECFA) and the detection results of hepatitis B virus ( HBV) indicator in Chinese residents' blood sample in 2004. The data used in MOE model came from animal experiments, the fourth nutrition and health investigation among Chinese residents, and national inspection network for food contaminations. Mathematics model indicated that for those people who were exposed to aflatoxins at average level (665.43 ng/d), the liver cancer incidence rate resulting from aflatoxins exposure was 0.4033 per 100 thousand person years. For those people who were exposed to aflatoxins at a high level (97.5 percentile, 24 787.20 ng/d) the liver cancer incidence rate attributed to aflatoxins exposure was 15.0215 per 100 thousand person years. Results from the MOE method showed that for the people in whole country, urban and rural areas who were exposed to aflatoxins at average level (0.011 09, 0.008 13 and 0.012 49 microg x kg(-1) x d(-1) respectively), the MOE values for aflatoxins to cause liver cancer were 9017.1, 12 304.7 and 8006.4 respectively. For those people who were exposed to aflatoxins at a high level (97.5 percentile, 0.413 10, 0.289 30 and 0.489 50 microg x kg(-1) x d(-1) respectively), the MOE values for aflatoxins to cause liver cancer were 242.1, 345.7 and 204.3 for whole country, urban and rural areas, respectively. For the people whose dietary aflatoxins exposure at average level, the risk of liver cancer attributed to aflatoxins is middle. For the people whose dietary aflatoxins exposure at high level, this kind of risk should be high.

  1. Current Understanding on Aflatoxin Biosynthesis and Future Perspective in Reducing Aflatoxin Contamination

    PubMed Central

    Yu, Jiujiang

    2012-01-01

    Traditional molecular techniques have been used in research in discovering the genes and enzymes that are involved in aflatoxin formation and genetic regulation. We cloned most, if not all, of the aflatoxin pathway genes. A consensus gene cluster for aflatoxin biosynthesis was discovered in 2005. The factors that affect aflatoxin formation have been studied. In this report, the author summarized the current status of research progress and future possibilities that may be used for solving aflatoxin contamination. PMID:23202305

  2. Dietary exposure to aflatoxin from maize and groundnut in young children from Benin and Togo, West Africa.

    PubMed

    Egal, S; Hounsa, A; Gong, Y Y; Turner, P C; Wild, C P; Hall, A J; Hell, K; Cardwell, K F

    2005-10-15

    impact of groundnut consumption on aflatoxin exposure was limited in this population. High AF-alb adduct levels were correlated with high prevalence of A. flavus and aflatoxin in groundnut, but significance was weak after adjustment for weaning status, agro-ecological zone and maternal socio-economic status (resp. p=0.091 and p=0.083). Ingestion of A. flavus and aflatoxin was high in certain agro-ecological zones (SS and SGS) and among the higher socio-economic strata due to higher frequencies of groundnut consumption. Contamination of groundnuts was similar across socio-economic and agro-ecological boundaries. In conclusion, dietary exposure to aflatoxin from groundnut was less than from maize in young children from Benin and Togo. Intervention strategies that aim to reduce dietary exposure in this population need to focus on maize consumption in particular, but they should not ignore consumption of groundnuts.

  3. A mini review on aflatoxin exposure in Malaysia: past, present and future

    PubMed Central

    Mohd-Redzwan, Sabran; Jamaluddin, Rosita; Abd.-Mutalib, Mohd Sokhini; Ahmad, Zuraini

    2013-01-01

    This mini review article described the exposure of aflatoxin in Malaysia, including its presence in the foodstuffs and the detection of aflatoxin biomarkers in human biological samples. Historically, the exposure of aflatoxin in Malaysia can be dated in 1960s where an outbreak of disease in pig farms caused severe liver damage to the animals. Later, an aflatoxicosis case in Perak in 1988 was reported and caused death to 13 children, as up to 3 mg of aflatoxin was present in a single serving of contaminated noodles. Since then, extensive research on aflatoxin has been conducted in Malaysia. The food commodities such as peanuts, cereals, spices, and their products are the main commodities commonly found to be contaminated with aflatoxin. Surprisingly, some of the contaminated foods had levels greater than the permissible limit adopted by the Malaysian Food Regulation 1985. Besides, exposure assessment through the measurement of aflatoxin biomarkers in human biological samples is still in its infancy stage. Nevertheless, some studies had reported the presence of these biomarkers. In fact, it is postulated that Malaysians are moderately exposed to aflatoxin compared to those high risk populations, where aflatoxin contamination in the diets is prevalent. Since the ingestion of aflatoxin could be the integral to the development of liver cancer, the incidence of cancer attributable by dietary aflatoxin exposure in Malaysia has also been reported and published in the literatures. Regardless of these findings, the more important task is to monitor and control humans from being exposed to aflatoxin. The enforcement of law is insufficient to minimize human exposure to aflatoxin. Preventive strategies include agricultural, dietary, and clinical measures should be implemented. With the current research on aflatoxin in Malaysia, a global networking for research collaboration is needed to expand the knowledge and disseminate the information to the global scientific community

  4. A mini review on aflatoxin exposure in Malaysia: past, present and future.

    PubMed

    Mohd-Redzwan, Sabran; Jamaluddin, Rosita; Abd-Mutalib, Mohd Sokhini; Ahmad, Zuraini

    2013-11-13

    This mini review article described the exposure of aflatoxin in Malaysia, including its presence in the foodstuffs and the detection of aflatoxin biomarkers in human biological samples. Historically, the exposure of aflatoxin in Malaysia can be dated in 1960s where an outbreak of disease in pig farms caused severe liver damage to the animals. Later, an aflatoxicosis case in Perak in 1988 was reported and caused death to 13 children, as up to 3 mg of aflatoxin was present in a single serving of contaminated noodles. Since then, extensive research on aflatoxin has been conducted in Malaysia. The food commodities such as peanuts, cereals, spices, and their products are the main commodities commonly found to be contaminated with aflatoxin. Surprisingly, some of the contaminated foods had levels greater than the permissible limit adopted by the Malaysian Food Regulation 1985. Besides, exposure assessment through the measurement of aflatoxin biomarkers in human biological samples is still in its infancy stage. Nevertheless, some studies had reported the presence of these biomarkers. In fact, it is postulated that Malaysians are moderately exposed to aflatoxin compared to those high risk populations, where aflatoxin contamination in the diets is prevalent. Since the ingestion of aflatoxin could be the integral to the development of liver cancer, the incidence of cancer attributable by dietary aflatoxin exposure in Malaysia has also been reported and published in the literatures. Regardless of these findings, the more important task is to monitor and control humans from being exposed to aflatoxin. The enforcement of law is insufficient to minimize human exposure to aflatoxin. Preventive strategies include agricultural, dietary, and clinical measures should be implemented. With the current research on aflatoxin in Malaysia, a global networking for research collaboration is needed to expand the knowledge and disseminate the information to the global scientific community.

  5. Aflatoxin

    MedlinePlus

    ... found in the following foods: Peanuts and peanut butter Tree nuts such as pecans Corn Wheat Oil ... foods that may contain aflatoxin. Peanuts and peanut butter are some of the most rigorously tested products ...

  6. Characterizing small RNA populations in non-transgenic and aflatoxin-reducing-transgenic peanut lines

    USDA-ARS?s Scientific Manuscript database

    Aflatoxin contamination is a major constraint in the food production worlwide. In peanut these aflatoxins are mainly produced by Aspergillus flavus (Link) and A. parasiticus (Speare). The use of RNA interference (RNAi) is a promising method to reduce or prevent the accumulation of aflatoxin in pean...

  7. Interactions between hepatitis B virus infection and exposure to aflatoxins in the development of hepatocellular carcinoma: a molecular epidemiological approach.

    PubMed

    Sylla, A; Diallo, M S; Castegnaro, J; Wild, C P

    1999-07-16

    Aflatoxins and hepatitis B virus (HBV) are major risk factors for hepatocellular carcinoma (HCC) in high incidence areas for this cancer, namely southeast Asia and parts of Africa. There is evidence from both epidemiological studies and animal models that the two factors can act synergistically to increase the risk of HCC. The cellular and molecular mechanism of the interaction between these two factors is as yet undefined. However, one possible mechanism attested to by studies in HBV transgenic mice is that chronic liver injury alters the expression of specific carcinogen metabolising enzymes thus modulating the binding of aflatoxin to DNA in hepatocytes. The high levels of aflatoxin exposure which occur in many areas of the world where chronic HBV infection is endemic indicate that measures to reduce aflatoxin exposure would contribute to reducing HCC incidence. In preliminary studies, Guinea-Conakry have established baseline data for the implementation of a community-based intervention study to evaluate the effectiveness of improved post-harvest processing and storage of the groundnut crop, a major source of aflatoxins. Aflatoxin-albumin adducts were measured in 423 sera from individuals living in the four natural geographic zones of Guinea. More than 95% of the serum samples were positive for this biomarker and highest exposures were found in Lower Guinea where groundnuts are consumed as a dietary staple. Variations in mean levels between villages within a geographic region did not vary greatly. HBV infection was endemic in all regions with an overall prevalence of 16.7% chronic carriers. Thus in this population both HBV vaccination and reduction in aflatoxin exposure would be beneficial in decreasing morbidity and mortality from liver disease.

  8. Cancer risk and occupational exposure to aflatoxins in Denmark.

    PubMed Central

    Olsen, J. H.; Dragsted, L.; Autrup, H.

    1988-01-01

    A study of cancer risk among male employees at 241 livestock feed processing companies in Denmark was conducted on the basis of a data linkage system for detailed investigation of occupational cancer providing employment histories back until 1964, established at the Danish Cancer Registry. Crops imported for feed production have often been contaminated with highly variable concentrations of aflatoxins; an estimated average concentration of at least 140 micrograms aflatoxin B1 kg-1 prepared mixed cattle feed prevailed in the past, yielding a daily intake for workers via the respiratory route of approximately 170 ng. Risk was established on the basis of cancer cases among male workers, whose employment in one of the companies was the job they had held for the longest time since 1964. Elevated risks for liver cancer and for cancers of the biliary tract were observed, which increased by two- to three-fold significance after a 10-year latency. Exposure to aflatoxins in the imported crops was judged to be the most probable explanation for these findings, although the influence of lifestyle factors, e.g. alcohol consumption on the results cannot be fully disregarded. Increased risks for salivary gland tumours and multiple myeloma were also detected. However, due to multiple comparisons carried out in this study these new associations must await further confirmation. A decreased risk for lung cancer was observed; despite possible negative confounding due to the smoking habits of the employees, the lung does not seem to be a target organ for the carcinogenic effect of inhaled aflatoxins in humans. PMID:3179193

  9. Aflatoxin levels and exposure assessment of Spanish infant cereals.

    PubMed

    Hernández-Martínez, Raquel; Navarro-Blasco, Iñigo

    2010-01-01

    Aflatoxins (AFB1, AFB2, AFG1 and AFG2) are immunosuppressant, mutagenic, teratogenic and carcinogenic agents with a widespread presence in foodstuffs. Since human exposure to aflatoxins occurs primarily by contaminated food intake, and given the greater susceptibility of infants to their adverse effects, the quantification of these mycotoxins in infant food based on cereals is of relevance. Aflatoxin levels were determined in 91 Spanish infant cereals classified in terms of non- and organically produced and several types from 10 different manufacturers, using a extraction procedure followed by inmunoaffinity column clean-up step and HPLC with fluorescence detection (FLD) and post-column derivatisation (Kobra Cell system). Daily aflatoxin intake was also assessed. Preliminary analysis showed a valuable incidence of detected infant cereal samples at an upper concentration level than the detection limit for total aflatoxin (66%), corresponding to a 46, 40, 34 and 11% for AFB1, AFB2, AFG1 and AFG2, respectively. Lower aflatoxin values (median, Q1, Q3) in conventional infant cereal (n = 74, AFB1: aflatoxin levels. Gluten-free and cereals with dehydrated fruits had an intermediate level and milk- or honey-based cereals and multi-cereals contained the lowest levels. With the exception of the non-compliant cocoa-based organic formulation

  10. Human aflatoxin exposure in Kenya, 2007: a cross-sectional study.

    PubMed

    Yard, Ellen E; Daniel, Johnni H; Lewis, Lauren S; Rybak, Michael E; Paliakov, Ekaterina M; Kim, Andrea A; Montgomery, Joel M; Bunnell, Rebecca; Abudo, Mamo Umuro; Akhwale, Willis; Breiman, Robert F; Sharif, Shahnaaz K

    2013-01-01

    Aflatoxins contaminate approximately 25% of agricultural products worldwide. They can cause liver failure and liver cancer. Kenya has experienced multiple aflatoxicosis outbreaks in recent years, often resulting in fatalities. However, the full extent of aflatoxin exposure in Kenya has been unknown. Our objective was to quantify aflatoxin exposure across Kenya. We analysed aflatoxin levels in serum specimens from the 2007 Kenya AIDS Indicator Survey - a nationally representative, cross-sectional serosurvey. KAIS collected 15,853 blood specimens. Of the 3180 human immunodeficiency virus-negative specimens with ≥1 mL sera, we randomly selected 600 specimens stratified by province and sex. We analysed serum specimens for aflatoxin albumin adducts by using isotope dilution MS/MS to quantify aflatoxin B1-lysine, and normalised with serum albumin. Aflatoxin concentrations were then compared by demographic, socioeconomic and geographic characteristics. We detected serum aflatoxin B1-lysine in 78% of serum specimens (range = Aflatoxin exposure did not vary by sex, age group, marital status, religion or socioeconomic characteristics. Aflatoxin exposure varied by province (p < 0.05); it was highest in Eastern (median = 7.87 pg/mg albumin) and Coast (median = 3.70 pg/mg albumin) provinces and lowest in Nyanza (median = aflatoxin exposure is a public health problem throughout Kenya, and it could be substantially impacting human health. Wide-scale, evidence-based interventions are urgently needed to decrease exposure and subsequent health effects.

  11. Mitigating aflatoxin exposure to improve child growth in Eastern Kenya: study protocol for a randomized controlled trial.

    PubMed

    Hoffmann, Vivian; Jones, Kelly; Leroy, Jef

    2015-12-03

    While the few studies that have looked at the association between stunting and aflatoxin exposure have found surprisingly large effects, the results remain inconclusive due to a lack of randomized controlled studies. This protocol describes a non-blinded, cluster-randomized controlled trial with the specific objective of testing the impact of reduced aflatoxin exposure on (individual) child linear growth. Participants were recruited from among households containing women in the last 5 months of pregnancy in 28 maize-growing villages within Meru and Tharaka-Nithi Counties in Kenya. Households in villages assigned to the intervention group are offered rapid testing of their stored maize for the presence of aflatoxin each month; any maize found to contain more than 10 ppb aflatoxin is replaced with an equal amount of maize that contains less than this concentration of the toxin. They are also offered the opportunity to buy maize that has been tested and found to contain less than 10 ppb aflatoxin at local shops. Clusters (villages) were allocated to the intervention group (28 villages containing 687 participating households) or control group (28 villages containing 536 participating households) using a random number generator. The trial, which is funded by United Kingdom (UK) aid from the UK government, the Global Food Security Portal, and the Ministry for Foreign Affairs of Finland, is currently ongoing. This study is the first randomized controlled trial (RCT) to test for a causal impact of aflatoxin exposure on child growth. Whether or not this relationship is found, its results will have implications for the prioritization of aflatoxin control efforts by governments in affected regions, as well as international donors. American Economic Association RCT Registry # 0000105 . Initial registration date: 6 November 2013, last updated 30 December 2014.

  12. Streptomyces sp. ASBV-1 reduces aflatoxin accumulation by Aspergillus parasiticus in peanut grains.

    PubMed

    Zucchi, T D; de Moraes, L A B; de Melo, I S

    2008-12-01

    To evaluate the ability of Streptomyces sp. (strain ASBV-1) to restrict aflatoxin accumulation in peanut grains. In the control of many phytopathogenic fungi the Streptomyces sp. ASBV-1 strain showed promise. An inhibitory test using this strain and A. parasiticus was conducted in peanut grains to evaluate the effects of this interaction on spore viability and aflatoxin accumulation. In some treatments the Streptomyces sp ASBV-1 strain reduced the viability of A. parasiticus spores by c. 85%, and inhibited aflatoxin accumulation in peanut grains. The values of these reductions ranged from 63 to 98% and from 67% to 96% for aflatoxins B(1) and G(1), respectively. It was demonstrated that Streptomyces sp. ASBV-1 is able to colonize peanut grains and thus inhibit the spore viability of A. parasiticus, as well as reducing aflatoxin production. The positive finding for aflatoxin accumulation reduction in peanut grains seems promising and suggests a wider use of this actinobacteria in biological control programmes.

  13. Aflatoxin exposure during the first 1000 days of life in rural South Asia assessed by aflatoxin B₁-lysine albumin biomarkers.

    PubMed

    Groopman, John D; Egner, Patricia A; Schulze, Kerry J; Wu, Lee S-F; Merrill, Rebecca; Mehra, Sucheta; Shamim, Abu A; Ali, Hasmot; Shaikh, Saijuddin; Gernand, Alison; Khatry, Subarna K; LeClerq, Steven C; West, Keith P; Christian, Parul

    2014-12-01

    Aflatoxin B1 is a potent carcinogen, occurring from mold growth that contaminates staple grains in hot, humid environments. In this investigation, aflatoxin B1-lysine albumin biomarkers were measured by mass spectrometry in rural South Asian women, during the first and third trimester of pregnancy, and their children at birth and at two years of age. These subjects participated in randomized community trials of antenatal micronutrient supplementation in Sarlahi District, southern Nepal and Gaibandha District in northwestern Bangladesh. Findings from the Nepal samples demonstrated exposure to aflatoxin, with 94% detectable samples ranging from 0.45 to 2939.30 pg aflatoxin B1-lysine/mg albumin during pregnancy. In the Bangladesh samples the range was 1.56 to 63.22 pg aflatoxin B1-lysine/mg albumin in the first trimester, 3.37 to 72.8 pg aflatoxin B1-lysine/mg albumin in the third trimester, 4.62 to 76.69 pg aflatoxin B1-lysine/mg albumin at birth and 3.88 to 81.44 pg aflatoxin B1-lysine/mg albumin at age two years. Aflatoxin B1-lysine adducts in cord blood samples demonstrated that the fetus had the capacity to convert aflatoxin into toxicologically active compounds and the detection in the same 2-year-old children illustrates exposure over the first 1000 days of life. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Dietary exposure to aflatoxin and micronutrient status among young children from Guinea.

    PubMed

    Watson, Sinead; Chen, Gaoyun; Sylla, Abdoulaye; Routledge, Michael N; Gong, Yun Yun

    2016-03-01

    Aflatoxin exposure coincides with micronutrient deficiencies in developing countries. Animal feeding studies have postulated that aflatoxin exposure may be exacerbating micronutrient deficiencies. Evidence available in human subjects is limited and inconsistent. The aim of the study was to investigate the relationship between aflatoxin exposure and micronutrient status among young Guinean children. A total of 305 children (28.8 ± 8.4 months) were recruited at groundnut harvest (rainy season), of which 288 were followed up 6 months later postharvest (dry season). Blood samples were collected at each visit. Aflatoxin-albumin adduct levels were measured by ELISA. Vitamin A, vitamin E and β-carotene concentrations were measured using HPLC methods. Zinc was measured by atomic absorption spectroscopy. Aflatoxin exposure and micronutrient deficiencies were prevalent in this population and were influenced by season, with levels increasing between harvest and postharvest. At harvest, children in the highest aflatoxin exposure group, compared to the lowest, were 1.98 (95%CI: 1.00, 3.92) and 3.56 (95%CI: 1.13, 11.15) times more likely to be zinc and vitamin A deficient. Although children with high aflatoxin exposure levels were more likely to be zinc and vitamin A deficient, further research is necessary to determine a cause and effect relationship. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Aflatoxins in hazelnuts and dried figs: Occurrence and exposure assessment.

    PubMed

    Kabak, Bulent

    2016-11-15

    A total of 300 samples of hazelnuts and dried fig were analysed for the incidence of any aflatoxins (AFs). High-performance liquid chromatography coupled with fluorescence detection (HPLC-FLD) method was used to quantify the amounts of AFs. The limit of quantification varied from 0.21 to 0.30μgkg(-1). No AFs were detected in shells of the hazelnuts, while six raw hazelnut kernel samples (12%) and five roasted hazelnut kernel samples (8.3%) contained AFs ranging from 0.09 to 11.3μgkg(-1) and from 0.17 to 11.2μgkg(-1), respectively. Sixteen dried fig samples (12.3%) contained AFs ranging from 0.1 to 28.2μgkg(-1) and a mean value of 3.8μgkg(-1). Three hazelnuts and six dried fig samples exceeded the European maximum limits (MLs) of 5 and 2μgkg(-1) for aflatoxin B1 (AFB1), respectively. The contribution of hazelnuts to AFs exposure is higher than that of dried figs.

  16. Occupational exposure to aflatoxin (AFB₁) in poultry production.

    PubMed

    Viegas, Susana; Veiga, Luisa; Malta-Vacas, Joana; Sabino, Raquel; Figueredo, Paula; Almeida, Ana; Viegas, Carla; Carolino, Elisabete

    2012-01-01

    Aflatoxin B₁ (AFB₁) has been recognized to produce cancer in human liver. In addition, epidemiological and laboratory studies demonstrated that the respiratory system was a target for AFB₁. Exposure occurs predominantly through the food chain, but inhalation represents an additional route of exposure. The present study aimed to examine AFB₁ exposure among poultry workers in Portugal. Blood samples were collected from a total of 31 poultry workers from six poultry farms. In addition, a control group (n = 30) was included comprised of workers who undertook administrative tasks. Measurement of AFB₁ in serum was performed by enzyme-linked immunosorbent assay (ELISA). For examining fungi contamination, air samples were collected through an impaction method. Air sampling was obtained in pavilion interior and outside the premises, since this was the place regarded as the reference location. Using molecular methods, toxicogenic strains (aflatoxin-producing) were investigated within the group of species belonging to Aspergillus flavus complex. Eighteen poultry workers (59%) had detectable levels of AFB₁ with values ranging from <1 ng/ml to 4.23 ng/ml and with a mean value of 2 ± 0.98 ng/ml. AFB₁ was not detected in the serum sampled from any of the controls. Aspergillus flavus was the fungal species third most frequently found in the indoor air samples analyzed (7.2%) and was the most frequently isolated species in air samples containing only Aspergillus genus (74.5%). The presence of aflatoxigenic strains was only confirmed in outdoor air samples from one of the units, indicating the presence of a source inside the building in at least one case. Data indicate that AFB₁ inhalation represents an additional risk in this occupational setting that needs to be recognized, assessed, and prevented.

  17. [Dietary exposure assessment of aflatoxin of foodstuff and edible oil from Shenzhen residents].

    PubMed

    Li, Ke; Qiu, Fen; Jiang, Lixin; Yang, Mei

    2014-07-01

    To assess the dietary exposure aflatoxin B1 and total aflatoxins of foodstuff and edible oil in Shenzhen residents. Aflatoxins in the samples were determined by the immuno-affinity column clean-up plus UPLC. The aflatoxin B1 and aflatoxins dietary exposure were calculated by the level of aflatoxins contamination in the food and consumption of dietary. The average diary aflatoxin B1 dietary exposure of the man of the 2 to 6, 7 to 14, 15 to 50 and > 50 age group in Shenzhen were 0.320, 0.385, 0.401 and 0.398 ng/(kg BW x d), the results of the woman were 0.282, 0.222, 0.367 and 0.470 ng/(kg BW x d) respectively. The total average daily dietary aflatoxin B1 exposure of the man were 0.012, 0.015, 0.016 and 0.016 ng/(kg BW x d) about each age group. The results of the woman were 78.4, 167, 113 and 103 ng/(kg BW d). According to the the average levels of consumption and the high levels of consumption, the risk of AFB, of the man were 0.012,0.015, 0.016, 0. 016 and 3.0, 8.2, 4.1, 4.4 cancer patient per one hundred thousand, respectively. The results of the woman were 0.010, 0.009, 0.014, 0.018 and 2.9, 6.7, 4.4, 4.0 cancer patient per one hundred thousand, respectively. 7 to 14 age group compared with adults age group face higher exposure levels. The rice and peanut oil are most primary aflatoxin dietary exposure sources in Shenzhen.

  18. Occupational exposure to Aspergillus and aflatoxins among food-grain workers in India

    PubMed Central

    Malik, Abida; Ali, Sana; Shahid, Mohd; Bhargava, Rakesh

    2014-01-01

    Background: Aflatoxins are a metabolite of Aspergillus molds and are widespread in the natural environment. Workers who handle food grains are at increased risk of exposure to aflatoxins and subsequently certain respiratory conditions. In India, more than half of the employed population is engaged in some type of agricultural work, yet little known about the respiratory problems as a result of exposure to aflatoxins among workers who handle food grains in India. Objectives: The aim of this study was to determine the risk of occupational exposure to aflatoxins in food-grain workers compared to workers who are not occupationally exposed to food grains. Methods: Bronchoalveolar lavage (BAL) and serum samples from 46 food-grain workers and 44 non-food-grain workers were analyzed for the presence of aflatoxins. Microscopy and culture of BAL samples were performed to detect Aspergillus species. Results: Aflatoxins were detected in 32.6% of the food-grain workers and 9.1% of non food grain workers (P<0.01). A significant difference was also found in BAL culture for Aspergillus (P<0.01) between the two groups. About 47.8% of the food-grain workers and 11.4% of non-food-grain workers had chronic respiratory symptoms. Conclusion: Occupational exposure to aflatoxins in food-grain workers was found to be associated with the increased presence of respiratory symptoms. PMID:25000106

  19. Occupational exposure to Aspergillus and aflatoxins among food-grain workers in India.

    PubMed

    Malik, Abida; Ali, Sana; Shahid, Mohd; Bhargava, Rakesh

    2014-01-01

    Aflatoxins are a metabolite of Aspergillus molds and are widespread in the natural environment. Workers who handle food grains are at increased risk of exposure to aflatoxins and subsequently certain respiratory conditions. In India, more than half of the employed population is engaged in some type of agricultural work, yet little known about the respiratory problems as a result of exposure to aflatoxins among workers who handle food grains in India. The aim of this study was to determine the risk of occupational exposure to aflatoxins in food-grain workers compared to workers who are not occupationally exposed to food grains. Bronchoalveolar lavage (BAL) and serum samples from 46 food-grain workers and 44 non-food-grain workers were analyzed for the presence of aflatoxins. Microscopy and culture of BAL samples were performed to detect Aspergillus species. Aflatoxins were detected in 32·6% of the food-grain workers and 9·1% of non food grain workers (P<0·01). A significant difference was also found in BAL culture for Aspergillus (P<0·01) between the two groups. About 47·8% of the food-grain workers and 11·4% of non-food-grain workers had chronic respiratory symptoms. Occupational exposure to aflatoxins in food-grain workers was found to be associated with the increased presence of respiratory symptoms.

  20. Risk of dietary exposure to aflatoxins and fumonisins in infants less than 6 months of age in Rombo, Northern Tanzania.

    PubMed

    Magoha, Happy; Kimanya, Martin; De Meulenaer, Bruno; Roberfroid, Dominique; Lachat, Carl; Kolsteren, Patrick

    2016-07-01

    Infants less than 6 months of age receiving foods other than breast milk are at a high risk of exposure to mycotoxins. We surveyed food intake and estimated the risk of exposures to aflatoxin and fumonisin mycotoxins for infants less than 6 months of age in Northern Tanzania. A total of 143 infants were progressively recruited and three follow-up visits were made at 1, 3 and 5 months of age. A 24-h dietary recall technique was used to estimate flour intake of infants who had been introduced to maize foods. Aflatoxins and fumonisins in the flours were analysed using high-performance liquid chromatography technique. Exposure to aflatoxins or fumonisins was estimated using the deterministic approach. By the age of 3 months, 98 infants had started taking food; 67 of them, maize flours at levels ranging from 0.57 to 37.50 g per infant per day (average 8 g per infant per day). Fifty-eight per cent of 67 maize flour samples contained detectable aflatoxins (range 0.33-69.47 μg kg(-1) ; median 6 μg kg(-1) ) and 31% contained detectable fumonisins (range 48-1224 μg kg(-1) ; median 124 μg kg(-1) ). For infants who consumed contaminated flours, aflatoxin exposure ranged from 0.14 to 120 ng kg(-1) body weight (BW) per day (all above the health concern level of 0.017 ng kg(-1) BW per day as recommended by the European Food Safety Agency) and fumonisin exposure ranged from 0.005 to 0.88 μg kg(-1) BW per day. Insignificant association was observed between exposure to fumonisins or aflatoxins and stunting or underweight. Reducing aflatoxin and fumonisin contamination of maize and dietary diversification can prevent infants and the public, in general, from exposure to the toxins. © 2014 John Wiley & Sons Ltd.

  1. Household dietary exposure to aflatoxins from maize and maize products in Kenya.

    PubMed

    Kilonzo, Robert M; Imungi, Jasper K; Muiru, William M; Lamuka, Peter O; Njage, Patrick M Kamau

    2014-01-01

    Aflatoxicosis has repeatedly affected Kenyans, particularly in the eastern region, due to consumption of contaminated maize. However, save for the cases of acute toxicity, the levels of sub-lethal exposure have not been adequately assessed. It is believed that this type of exposure does exist even during the seasons when acute toxicity does not occur. This study, therefore, was designed to assess the exposure of households to aflatoxins through consumption of maize and maize products. Twenty samples each of maize kernels, muthokoi and maize meal were randomly sampled from households in Kibwezi District of Makueni County in Eastern Kenya and analysed for aflatoxin contamination. The samples were quantitatively analysed for aflatoxin contamination using HPLC. The uncertainty and variability in dietary exposure was quantitatively modelled in Ms Excel using Monte Carlo simulation in @Risk software. Aflatoxins were found in 45% of maize kernels at between 18 and 480 μg kg⁻¹, 20% of muthokoi at between 12 and 123 μg kg⁻¹, and 35% of maize meal at between 6 and 30 μg kg⁻¹. The mean dietary exposure to aflatoxin in maize kernels was 292 ± 1567 ng kg⁻¹ body weight day⁻¹, while the mean dietary exposure to aflatoxin in maize meal and muthokoi were 59 ± 62 and 27 ± 154 ng kg⁻¹ body weight day⁻¹ respectively. The results showed that the amount and frequency of consumption of the three foods is the more important contributing factor than the mean aflatoxin concentration levels, to the risk of dietary exposure to aflatoxins.

  2. Occurrence and exposure assessment of aflatoxins in Catalonia (Spain).

    PubMed

    Cano-Sancho, G; Sanchis, V; Marín, S; Ramos, A J

    2013-01-01

    The main objective of this study was to assess the exposure of Catalonian (Spain) population to AFs. Thus, two sub-objectives were considered: (1) to assess the occurrence of AFs in food marketed in Catalonia, and (2) to assess the consumption of those foods susceptible to AFs contamination by Catalonian population. AFs were analysed in a total of 603 samples considering special commodities as free-gluten, ethnic or baby foods. Analytical method consisted of an extraction and clean-up of aflatoxins step using immunoaffinity columns, and determination by HPLC with post-column photochemical derivatization and fluorescence detection. Food dietary intake was assessed using a food frequency questionnaire, administered to 1387 individuals by trained interviewers. Contamination and consumption raw datasets were combined by means of a direct method and a stochastic method, building the pseudo-parametric bootstrap confidence intervals of the main outputs. Margins of exposure (MoE) and cancer incidence were estimated for the different collectives. The highest percentages of positive samples were found in red pepper, pistachios and peanuts. Considering our results, the most exposed group was the celiac sufferer collective followed by the adolescents; however health concern should not be expected in the population groups. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. Infants exposure to aflatoxin M₁ as a novel foodborne zoonosis.

    PubMed

    El-Tras, Wael F; El-Kady, Nevein N; Tayel, Ahmed A

    2011-11-01

    Occurrence of aflatoxin M(1) (AFM(1)) in infant formula milk powder (IFMP) and maternal breast milk (MBM) was investigated as a risk factor affects the health of newborns in Egypt. A total of 125 IFMP and 125 MBM samples were collected and examined for the presence of AFM(1) using competitive ELISA test. The results indicated that the relative risk (RR) of exposure to AFM(1) via consumption of MBM was higher than IFMP (RR; 1.6, 95%CI; 1.28-2.03, p=0.0001). The mean concentrations of AFM(1) were significantly differed (p<0.0001) between MBM (74.413 ± 7.070 ng/l) and IFMP (9.796 ± 1.036 ng/l). High frequency distributions were detected within the range of 5-25 ng/l and >50-100 ng/l in IFMP and MBM, respectively. The average daily exposure of newborns to AFM(1) via consumption of MBM and IFMP was 52.684 and 8.170 ng, respectively, with a significant difference at p<0.0001. Consumption of raw milk by lactating mothers exhibited a significant correlation (p<0.0001) with the presence of AFM(1) in their milk. In conclusion, this work established a pioneering concept that AFM(1) may be considered as an etiological factor for a novel foodborne zoonosis identified as Aflatoxicosis M(1). Copyright © 2011 Elsevier Ltd. All rights reserved.

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

    USDA-ARS?s Scientific Manuscript database

    Background: 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. An oral dose of calcium montmorillonite clay (i.e. NovaSil, NS) was able to reduce aflatoxin exposure in a Ghanaian population at risk. In vitro...

  5. Occupational Exposure to Aflatoxin B1 in a Portuguese Poultry Slaughterhouse.

    PubMed

    Viegas, Susana; Veiga, Luísa; Almeida, Ana; dos Santos, Mateus; Carolino, Elisabete; Viegas, Carla

    2016-03-01

    Aflatoxin B1 (AFB1) is a secondary metabolite produced by the fungi Aspergillus flavus and is the most potent hepatocarcinogen known in mammals and has been classified by the International Agency of Research on Cancer as Group 1 carcinogen. Although dietary exposure to AFB1 has been extensively documented, there are still few studies dedicated to the problem of occupational exposure. Considering recent findings regarding AFB1 occupational exposure in poultry production, it was considered relevant to clarify if there is also exposure in poultry slaughterhouses. Occupational exposure assessment to AFB1 was done with a biomarker of internal dose that measures AFB1 in the serum by enzyme-linked immunosorbent assay. Thirty workers from a slaughterhouse were enrolled in this study. A control group (n = 30) was also considered in order to know AFB1 background levels for Portuguese population. Fourteen workers (47.0%) showed detectable levels of AFB1 with values from 1.06 to 4.03ng ml(-1), with a mean value of 1.73ng ml(-1). No AFB1 was detected in serum of individuals used as controls. Despite uncertainties regarding the exposure route that is contributing more to exposure (inhalation or dermal) is possible to state that exposure to AFB1 is occurring in the slaughterhouse studied. It seems that reducing AFB1 contamination in poultry production can have a positive result in this occupational setting. © The Author 2015. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  6. Hepatocellular carcinoma p53 G > T transversions at codon 249: the fingerprint of aflatoxin exposure?

    PubMed

    Lasky, T; Magder, L

    1997-04-01

    The molecular epidemiology of p53 mutations allows the possibility of correlating particular mutations with specific environmental carcinogens and establishing one step in the causal pathway between exposure to carcinogens and the development of cancer. A striking example is the G > T transversion at the third base pair of codon 249 observed in liver cancer patients possibly exposed to high levels of aflatoxins in their agricultural products. In this paper, we describe a systematic review of the literature and access the quality of the available data. We found methodologic limitations in the studies. In particular, the key independent variable, aflatoxin exposure, was not assessed in these studies, with the exception of one study that measured a marker of exposure. Instead, nationality, geographic residence, or geographic site of hospital were used as surrogate markers for exposure. Patients from areas with high aflatoxin levels were more likely to have p53 mutations than were patients from areas with low aflatoxin levels. In the group with p53 mutations, patients from areas with high aflatoxin levels had higher proportions of mutations with codon 249 G > T transversions. The differences in proportions with p53 mutations were significant, as were the differences in proportions of codon 249 G > T transversions among patients with p53 mutations. Aflatoxin may increase the proportion of p53 mutations by causing a single mutation, the codon 249 G > T transversion, thus explaining some of the excess liver cancer associated with aflatoxin exposure. However, it is premature to conclude that p53 mutations are established markers for environmental carcinogens.

  7. The threats to food safety and biocontrol of aflatoxins

    USDA-ARS?s Scientific Manuscript database

    Aflatoxins are a serious food safety concern for human and animal health. Great attention should be paid to the dietary exposure to these toxins in order to reduce the risk of aflatoxin contamination in the food chain. Although the research on aflatoxins was started more than 50 years ago, it is sti...

  8. Characterization of small RNA populations in non-transgenic and aflatoxin-reducing-transformed peanut.

    PubMed

    Power, Imana L; Dang, Phat M; Sobolev, Victor S; Orner, Valerie A; Powell, Joseph L; Lamb, Marshall C; Arias, Renee S

    2017-04-01

    Aflatoxin contamination is a major constraint in food production worldwide. In peanut (Arachis hypogaea L.), these toxic and carcinogenic aflatoxins are mainly produced by Aspergillus flavus Link and A. parasiticus Speare. The use of RNA interference (RNAi) is a promising method to reduce or prevent the accumulation of aflatoxin in peanut seed. In this study, we performed high-throughput sequencing of small RNA populations in a control line and in two transformed peanut lines that expressed an inverted repeat targeting five genes involved in the aflatoxin-biosynthesis pathway and that showed up to 100% less aflatoxin B1 than the controls. The objective was to determine the putative involvement of the small RNA populations in aflatoxin reduction. In total, 41 known microRNA (miRNA) families and many novel miRNAs were identified. Among those, 89 known and 10 novel miRNAs were differentially expressed in the transformed lines. We furthermore found two small interfering RNAs derived from the inverted repeat, and 39 sRNAs that mapped without mismatches to the genome of A. flavus and were present only in the transformed lines. This information will increase our understanding of the effectiveness of RNAi and enable the possible improvement of the RNAi technology for the control of aflatoxins.

  9. Dietary exposure to aflatoxin and fumonisin among Tanzanian children as determined using biomarkers of exposure

    PubMed Central

    Shirima, Candida P.; Kimanya, Martin E.; Kinabo, Joyce L.; Routledge, Michael N.; Srey, Chou; Wild, Christopher P.; Gong, Yun Yun

    2014-01-01

    Scope The study aims to evaluate the status of dietary exposure to aflatoxin and fumonisin in young Tanzanian children, using previously validated biomarkers of exposure. Methods and results A total of 148 children aged 12 to 22 months, were recruited from three geographically distant villages in Tanzania; Nyabula, Kigwa and Kikelelwa. Plasma aflatoxin-albumin adducts (AF-alb) and urinary fumonisin B1 (UFB1) were measured by ELISA and LC-MS, respectively. AF-alb was detectable in 84% of children, was highest in fully weaned children (p<0.01) with higher levels being associated with higher maize intake (p<0.05). AF-alb geometric mean (95% CI) was 43.2 (28.7–65.0), 19.9 (13.5–29.2) and 3.6 (2.8–4.7) pg/mg albumin in children from Kigwa, Nyabula and Kikelelwa, respectively. UFB1 was detectable in 96% of children and the level was highest in children who had been fully weaned (p<0.01). The geometric UFB1 mean (95% CI) was 327.2 (217.1–493.0), 211.7 (161.1–278.1) and 82.8 (58.3–117.7) pg/ml in Kigwa, Nyabula and Kikelelwa, respectively. About 82% of all the children were exposed to both mycotoxins. Conclusion Young children in Tanzania are chronically exposed to both aflatoxin and fumonisin through contaminated diet, although the level of exposure varies markedly between the three villages studied. PMID:23776058

  10. Suppression of spore germination and aflatoxin biosynthesis in Aspergillus parasiticus during and after exposure to high levels of phosphine.

    PubMed

    Antonacci, L; Salvat, A E; Faifer, G C; Godoy, H M

    1999-01-01

    Agar cultures of toxigenic Aspergillus parasiticus NRRL 2999 were exposed to phosphine (PH3), in levels ranging from 0 to 2000 ppm (vol/vol). It was found that with PH3 concentrations of 400 ppm or higher the growth of the fungus was totally arrested. When PH3 was vented and the agar plates were exposed to open air, 100% of the initial CFU developed into fully grown colonies after PH3 levels below 300 ppm, but at higher PH3 concentrations only 50% of the colonies developed. The same strain of A. parasiticus was inoculated into high moisture corn under conditions highly favorable for aflatoxin production, and it was exposed to a range of PH3 levels. After exposure to 500 ppm PH3, both fungal growth and aflatoxin synthesis resumed shortly after elimination of the toxic gas, but after exposure to PH3 levels of 1000 ppm and higher, the physical appearance of the contaminated corn was remarkably changed, showing reduced mycelial growth and almost complete absence of green pigmentation. In addition, aflatoxin synthesis was totally absent for the remainder of the experiment (20 days). These results strongly suggest that exposure to PH3 levels of 1000 ppm or higher could bring about persistent metabolic changes in surviving Aspergillus organisms.

  11. Application of superabsorbent polymers (SAP) as desiccants to dry maize and reduce aflatoxin contamination.

    PubMed

    Mbuge, Duncan O; Negrini, Renata; Nyakundi, Livine O; Kuate, Serge P; Bandyopadhyay, Ranajit; Muiru, William M; Torto, Baldwyn; Mezzenga, Raffaele

    2016-08-01

    The ability of superabsorbent polymers (SAP) in drying maize and controlling aflatoxin contamination was studied under different temperatures, drying times and SAP-to-maize ratios. Temperature and drying time showed significant influence on the aflatoxin formation. SAP-to-maize ratios between 1:1 and 1:5 showed little or no aflatoxin contamination after drying to the optimal moisture content (MC) of 13 %, while for ratios 1:10 and 1:20, aflatoxin contamination was not well controlled due to the overall higher MC and drying time, which made these ratios unsuitable for the drying process. Results clearly show that temperature, frequency of SAP change, drying time and SAP-to-maize ratio influenced the drying rate and aflatoxin contamination. Furthermore, it was shown that SAP had good potential for grain drying and can be used iteratively, which can make this system an optimal solution to reduce aflatoxin contamination in maize, particular for developing countries and resource-lacking areas.

  12. Does aflatoxin exposure in the United Kingdom constitute a cancer risk?

    PubMed Central

    Harrison, J C; Carvajal, M; Garner, R C

    1993-01-01

    Although the aflatoxins were discovered more than 30 years ago, there is still considerable controversy surrounding their human health effects. Most countries have introduced legislation to control the level of aflatoxins in food, but it is not known if these permitted levels still pose a significant cancer risk. Furthermore, it is unlikely that all the sources of human aflatoxin exposure have been discovered, nor if the liver is the only, or indeed, major target organ for aflatoxin-induced cancer in man. In our laboratory we have used both immunological and HPLC methods to examine human DNA from a variety of tissues and organs to identify and quantify aflatoxin DNA-adducts. We have already detected aflatoxin B1 (AFB1)-DNA adducts in formalin-fixed tissue from an acute poisoning incident in Southeast Asia. Here we have examined human colon and rectum DNA from normal and tumorous tissue obtained from cancer patients and colon, liver, pancreas, breast, and cervix DNA from autopsy specimens. AFB1-DNA adducts were detected in all tissue types examined and ranged from 0-60 adducts/10(6) nucleotides. Where sample size allowed, the adduct levels were confirmed by HPLC analysis. Tumor tissues tended to have higher adduct levels than normal tissue from the same individual, and levels generally increased with patient age. In samples analyzed by HPLC, the adducts present had the chromatographic properties of [8,9-dihydro-8-(N5-formyl)-2',5',6'-triamino-4'-oxo-(N5-pyramidyl) -9- hydroxy-aflatoxin B1, the ring-opened form of the AFB1-guanine adduct.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8319666

  13. Chronic aflatoxin exposure in children living in Bhaktapur, Nepal: Extension of the MAL-ED study

    USDA-ARS?s Scientific Manuscript database

    Fumonisin B1 (FB1) and aflatoxin B1 (AFB1) are toxic chemicals produced by molds. The molds that produce these two toxic chemicals are commonly found in corn and their co-occurence in corn has been demonstrated in many surveys. This study was conducted because it is suspected that exposure to eith...

  14. Exposure to aflatoxins in Japan: risk assessment for aflatoxin B1.

    PubMed

    Sugita-Konishi, Y; Sato, T; Saito, S; Nakajima, M; Tabata, S; Tanaka, T; Norizuki, H; Itoh, Y; Kai, S; Sugiyama, K; Kamata, Y; Yoshiike, N; Kumagai, S

    2010-03-01

    The intake of total aflatoxins (AFT) and aflatoxin B(1) (AFB(1)) from food in Japan was estimated from AFT and AFB(1) concentration and frequency data in 24 foods (884 samples) from a 3-year retail market survey from the summer of 2004 to the winter of 2006, and by food consumption data from the National Health and Nutrition Survey performed in 2005. The AFT and AFB(1) survey revealed that peanut, peanut products, cocoa, chocolate, pistachio, white pepper, red pepper, almond, job's tears, buckwheat and corn grits are considered to be contributors of AFT (or AFB(1)) intake in Japan (maximum AFB(1) (AFT) levels ranged from 0.21 to 28.0 microg kg(-1) (from 0.21 to 9.0 microg kg(-1))) in AFT-contaminated food. A probabilistic approach using the Monte Carlo method was carried out to simulate an estimate of the AFT (or AFB(1)) intake distributions in each age group in Japan. In this study, AFB(1) intake ranged from 0.003 to 0.004 ng kg(-1) body weight day(-1) (from lower to upper limits), and the potential risk for cancer using a formula devised by the Joint Food and Agricultural Organization/World Health Organization (FAO/WHO) Expert Committee on Food Additives (JECFA) was estimated at 0.00004-0.00005 person/year/100,000 persons, even though this was in the higher levels (95.0th percentile) of the consumer population. The results suggest that the current dietary intake of AFB(1) in Japan has no appreciable effect on health.

  15. Aflatoxin-Exposure of Vibrio gazogenes as a Novel System for the Generation of Aflatoxin Synthesis Inhibitors.

    PubMed

    Gummadidala, Phani M; Chen, Yung Pin; Beauchesne, Kevin R; Miller, Kristen P; Mitra, Chandrani; Banaszek, Nora; Velez-Martinez, Michelle; Moeller, Peter D R; Ferry, John L; Decho, Alan W; Chanda, Anindya

    2016-01-01

    Aflatoxin is a mycotoxin and a secondary metabolite, and the most potent known liver carcinogen that contaminates several important crops, and represents a significant threat to public health and the economy. Available approaches reported thus far have been insufficient to eliminate this threat, and therefore provide the rational to explore novel methods for preventing aflatoxin accumulation in the environment. Many terrestrial plants and microbes that share ecological niches and encounter the aflatoxin producers have the ability to synthesize compounds that inhibit aflatoxin synthesis. However, reports of natural aflatoxin inhibitors from marine ecosystem components that do not share ecological niches with the aflatoxin producers are rare. Here, we show that a non-pathogenic marine bacterium, Vibrio gazogenes, when exposed to low non-toxic doses of aflatoxin B1, demonstrates a shift in its metabolic output and synthesizes a metabolite fraction that inhibits aflatoxin synthesis without affecting hyphal growth in the model aflatoxin producer, Aspergillus parasiticus. The molecular mass of the predominant metabolite in this fraction was also different from the known prodigiosins, which are the known antifungal secondary metabolites synthesized by this Vibrio. Gene expression analyses using RT-PCR demonstrate that this metabolite fraction inhibits aflatoxin synthesis by down-regulating the expression of early-, middle-, and late- growth stage aflatoxin genes, the aflatoxin pathway regulator, aflR and one global regulator of secondary metabolism, laeA. Our study establishes a novel system for generation of aflatoxin synthesis inhibitors, and emphasizes the potential of the under-explored Vibrio's silent genome for generating new modulators of fungal secondary metabolism.

  16. Aflatoxin-Exposure of Vibrio gazogenes as a Novel System for the Generation of Aflatoxin Synthesis Inhibitors

    PubMed Central

    Gummadidala, Phani M.; Chen, Yung Pin; Beauchesne, Kevin R.; Miller, Kristen P.; Mitra, Chandrani; Banaszek, Nora; Velez-Martinez, Michelle; Moeller, Peter D. R.; Ferry, John L.; Decho, Alan W.; Chanda, Anindya

    2016-01-01

    Aflatoxin is a mycotoxin and a secondary metabolite, and the most potent known liver carcinogen that contaminates several important crops, and represents a significant threat to public health and the economy. Available approaches reported thus far have been insufficient to eliminate this threat, and therefore provide the rational to explore novel methods for preventing aflatoxin accumulation in the environment. Many terrestrial plants and microbes that share ecological niches and encounter the aflatoxin producers have the ability to synthesize compounds that inhibit aflatoxin synthesis. However, reports of natural aflatoxin inhibitors from marine ecosystem components that do not share ecological niches with the aflatoxin producers are rare. Here, we show that a non-pathogenic marine bacterium, Vibrio gazogenes, when exposed to low non-toxic doses of aflatoxin B1, demonstrates a shift in its metabolic output and synthesizes a metabolite fraction that inhibits aflatoxin synthesis without affecting hyphal growth in the model aflatoxin producer, Aspergillus parasiticus. The molecular mass of the predominant metabolite in this fraction was also different from the known prodigiosins, which are the known antifungal secondary metabolites synthesized by this Vibrio. Gene expression analyses using RT-PCR demonstrate that this metabolite fraction inhibits aflatoxin synthesis by down-regulating the expression of early-, middle-, and late- growth stage aflatoxin genes, the aflatoxin pathway regulator, aflR and one global regulator of secondary metabolism, laeA. Our study establishes a novel system for generation of aflatoxin synthesis inhibitors, and emphasizes the potential of the under-explored Vibrio’s silent genome for generating new modulators of fungal secondary metabolism. PMID:27375561

  17. Sampling hazelnuts for aflatoxin: effect of sample size and accept/reject limit on reducing the risk of misclassifying lots.

    PubMed

    Ozay, Guner; Seyhan, Ferda; Yilmaz, Aysun; Whitaker, Thomas B; Slate, Andrew B; Giesbrecht, Francis G

    2007-01-01

    About 100 countries have established regulatory limits for aflatoxin in food and feeds. Because these limits vary widely among regulating countries, the Codex Committee on Food Additives and Contaminants began work in 2004 to harmonize aflatoxin limits and sampling plans for aflatoxin in almonds, pistachios, hazelnuts, and Brazil nuts. Studies were developed to measure the uncertainty and distribution among replicated sample aflatoxin test results taken from aflatoxin-contaminated treenut lots. The uncertainty and distribution information is used to develop a model that can evaluate the performance (risk of misclassifying lots) of aflatoxin sampling plan designs for treenuts. Once the performance of aflatoxin sampling plans can be predicted, they can be designed to reduce the risks of misclassifying lots traded in either the domestic or export markets. A method was developed to evaluate the performance of sampling plans designed to detect aflatoxin in hazelnuts lots. Twenty hazelnut lots with varying levels of contamination were sampled according to an experimental protocol where 16 test samples were taken from each lot. The observed aflatoxin distribution among the 16 aflatoxin sample test results was compared to lognormal, compound gamma, and negative binomial distributions. The negative binomial distribution was selected to model aflatoxin distribution among sample test results because it gave acceptable fits to observed distributions among sample test results taken from a wide range of lot concentrations. Using the negative binomial distribution, computer models were developed to calculate operating characteristic curves for specific aflatoxin sampling plan designs. The effect of sample size and accept/reject limits on the chances of rejecting good lots (sellers' risk) and accepting bad lots (buyers' risk) was demonstrated for various sampling plan designs.

  18. Aflatoxin exposure during the first 36 months of life was not associated with impaired growth in Nepalese children: An extension of the MAL-ED study

    PubMed Central

    Hsu, Hui-Husan; Chandyo, Ram Krishna; Shrestha, Binob; Bodhidatta, Ladaporn; Tu, Yu-Kang; Gong, Yun-Yun; Egner, Patricia A.; Ulak, Manjeswori; Groopman, John D.; Wu, Felicia

    2017-01-01

    Exposure to aflatoxin, a mycotoxin common in many foods, has been associated with child growth impairment in sub-Saharan Africa. To improve our understanding of growth impairment in relation to aflatoxin and other risk factors, we assessed biospecimens collected in Nepalese children at 15, 24, and 36 months of age for aflatoxin exposure. Children (N = 85) enrolled in the Bhaktapur, Nepal MAL-ED study encompassed the cohort analysed in this study. Exposure was assessed through a plasma biomarker of aflatoxin exposure: the AFB1-lysine adduct. The aflatoxin exposures in the study participants were compared to anthropometrics at each time period (length-for-age [LAZ], weight-for-age [WAZ], and weight-for-length [WLZ] z-scores), growth trajectories over time, age, and breastfeeding status. Results demonstrated chronic aflatoxin exposure in this cohort of children, with a geometric mean of 3.62 pg AFB1-lysine/mg albumin. However, the chronic aflatoxin exposure in this cohort was not significantly associated with anthropometric z-scores, growth trajectories, age, or feeding status, based on the available time points to assess aflatoxin exposure. Low mean levels of aflatoxin exposure and infrequent occurrence of stunting, wasting, or underweight z-score values in this cohort are possible contributing factors to a lack of evidence for an association. Further research is needed to examine whether a threshold dose of aflatoxin exists that could induce child growth impairment. PMID:28212415

  19. Aflatoxin exposure during the first 36 months of life was not associated with impaired growth in Nepalese children: An extension of the MAL-ED study.

    PubMed

    Mitchell, Nicole J; Hsu, Hui-Husan; Chandyo, Ram Krishna; Shrestha, Binob; Bodhidatta, Ladaporn; Tu, Yu-Kang; Gong, Yun-Yun; Egner, Patricia A; Ulak, Manjeswori; Groopman, John D; Wu, Felicia

    2017-01-01

    Exposure to aflatoxin, a mycotoxin common in many foods, has been associated with child growth impairment in sub-Saharan Africa. To improve our understanding of growth impairment in relation to aflatoxin and other risk factors, we assessed biospecimens collected in Nepalese children at 15, 24, and 36 months of age for aflatoxin exposure. Children (N = 85) enrolled in the Bhaktapur, Nepal MAL-ED study encompassed the cohort analysed in this study. Exposure was assessed through a plasma biomarker of aflatoxin exposure: the AFB1-lysine adduct. The aflatoxin exposures in the study participants were compared to anthropometrics at each time period (length-for-age [LAZ], weight-for-age [WAZ], and weight-for-length [WLZ] z-scores), growth trajectories over time, age, and breastfeeding status. Results demonstrated chronic aflatoxin exposure in this cohort of children, with a geometric mean of 3.62 pg AFB1-lysine/mg albumin. However, the chronic aflatoxin exposure in this cohort was not significantly associated with anthropometric z-scores, growth trajectories, age, or feeding status, based on the available time points to assess aflatoxin exposure. Low mean levels of aflatoxin exposure and infrequent occurrence of stunting, wasting, or underweight z-score values in this cohort are possible contributing factors to a lack of evidence for an association. Further research is needed to examine whether a threshold dose of aflatoxin exists that could induce child growth impairment.

  20. Regression of Aflatoxin B1-Induced Hepatocellular Carcinomas by Reduced Glutathione

    NASA Astrophysics Data System (ADS)

    Novi, Anna M.

    1981-05-01

    Reduced glutathione administered to rats bearing aflatoxin B1-induced liver tumors caused regression of tumor growth and resulted in survival of the animals. Since glutathione is a harmless natural product, it merits further investigation as a potential antitumor drug for humans.

  1. Aflatoxins in Iran: Nature, Hazards and Carcinogenicity

    PubMed Central

    Khoshpey, B; Farhud, DD; Zaini, F

    2011-01-01

    Many studies have shown that mycotoxin contamination of agricultural products is a challenge for individual’s health especially in developing countries. Improper production and storage of foods, prepare conditions for aflatoxin production in crops, especially rice, wheat, pistachio, walnut, almond, etc which are the main sources of foods for people. Feeding livestock by contaminated bread is another way of human exposure to mycotoxins, especially aflatoxin and because of expensive methods for detecting and analyzing aflatoxin in laboratory; it is not measured in foods. This manuscript is a review of some Iranian and nonIranian reports about aflatoxin, its exposure ways, its adverse effect on human health and nutrition, as well as methods for reducing its exposure. Based on studies on foods, aflatoxin exposure is high in Iran. Since livestock feeding by contaminated bread is one of the potential ways for milk contamination, we should control and reduce aflatoxin contamination by improving production process, storage condition and livestock feeding as soon as possible. Pistachio is one of the most important exporting products of Iran and to maintain Iran’s position in exporting of this product, specific regulations on lowering its contamination with aflatoxin should be considered seriously. Finally, effective controlling of all food and feedstuffs which are vulnerable to aflatoxin contamination is necessary to prevent its effects. PMID:23113099

  2. Aflatoxins in iran: nature, hazards and carcinogenicity.

    PubMed

    Khoshpey, B; Farhud, Dd; Zaini, F

    2011-12-01

    Many studies have shown that mycotoxin contamination of agricultural products is a challenge for individual's health especially in developing countries. Improper production and storage of foods, prepare conditions for aflatoxin production in crops, especially rice, wheat, pistachio, walnut, almond, etc which are the main sources of foods for people. Feeding livestock by contaminated bread is another way of human exposure to mycotoxins, especially aflatoxin and because of expensive methods for detecting and analyzing aflatoxin in laboratory; it is not measured in foods. This manuscript is a review of some Iranian and nonIranian reports about aflatoxin, its exposure ways, its adverse effect on human health and nutrition, as well as methods for reducing its exposure. Based on studies on foods, aflatoxin exposure is high in Iran. Since livestock feeding by contaminated bread is one of the potential ways for milk contamination, we should control and reduce aflatoxin contamination by improving production process, storage condition and livestock feeding as soon as possible. Pistachio is one of the most important exporting products of Iran and to maintain Iran's position in exporting of this product, specific regulations on lowering its contamination with aflatoxin should be considered seriously. Finally, effective controlling of all food and feedstuffs which are vulnerable to aflatoxin contamination is necessary to prevent its effects.

  3. Exposure of Infants to Aflatoxin M1 from Mother's Breast Milk in Ilam, Western Iran

    PubMed Central

    Maleki, Farajollah; Abdi, Soghra; Davodian, Elaham; Haghani, Karimeh; Bakhtiyari, Salar

    2015-01-01

    Objectives Aflatoxins as a highly toxic group of mycotoxins are present in the environment and foodstuff. These have been reported to cause serious health problems in humans. Since aflatoxin M1 (AFM1) is excreted into breast milk, investigating the exposure of infants to AFM1 is of special concern. Methods In the present study, breast milk samples were collected from 85 lactating mothers in Ilam province, Iran, and the levels of AFM1 were analyzed using the enzyme-linked immunosorbent assay-based technique. AFM1 was detected in breast milk of all lactating women. The mean contamination level was 5.91 ± 2.031 ng/L, ranging from 2 ng/L to 10 ng/L. Results Multiple regression analysis indicated no significant associations of consumption of milk and dairy products, meat, fish, legumes, grain products, fruits, and nuts with the concentration of AFM1 in breast milk. Furthermore, no significant association was observed between AFM1 concentration and anthropometric data of infants. Conclusion In western parts of Iran, lactating mothers and their infants could be at risk of aflatoxin B1 and AFM1 exposure, respectively. Therefore, in Iran, the evaluation of AFM1 in human breast milk as a biomarker for postnatal exposure of infants to this carcinogen requires more attention in different regions and various seasons. PMID:26929911

  4. Dietary exposure to aflatoxin B1, ochratoxin A and fuminisins of adults in Lao Cai province, Viet Nam: A total dietary study approach.

    PubMed

    Huong, Bui Thi Mai; Tuyen, Le Danh; Tuan, Do Huu; Brimer, Leon; Dalsgaard, Anders

    2016-12-01

    Aflatoxins, fumonisins and ochratoxin A that contaminate various agricultural commodities are considered of significant toxicity and potent human carcinogens. This study took a total dietary study approach and estimated the dietary exposure of these mycotoxins for adults living in Lao Cai province, Vietnam. A total of 42 composite food samples representing 1134 individual food samples were prepared according to normal household practices and analysed for the three mycotoxins. Results showed that the dietary exposure to aflatoxin B1 (39.4 ng/kg bw/day) and ochratoxin A (18.7 ng/kg bw/day) were much higher than recommended provisional tolerable daily intake (PTDI) values mainly due to contaminated cereals and meat. The exposure to total fumonisins (1400 ng/kg bw/day) was typically lower than the PTDI value (2000 ng/kg bw/day). The estimated risk of liver cancer associated with exposure to aflatoxin B1 was 2.7 cases/100,000 person/year. Margin of exposure (MOE) of renal cancer linked to ochratoxin A and liver cancer associated with fumonisins were 1124 and 1954, respectively indicating risk levels of public health concern. Further studies are needed to evaluate the efficiency of technical solutions which could reduce mycotoxin contamination as well as to determine the health effects of the co-exposure to different types of mycotoxins.

  5. Lactobacillus rhamnosus Strain GG Reduces Aflatoxin B1 Transport, Metabolism, and Toxicity in Caco-2 Cells▿

    PubMed Central

    Gratz, S.; Wu, Q. K.; El-Nezami, H.; Juvonen, R. O.; Mykkänen, H.; Turner, P. C.

    2007-01-01

    The probiotic Lactobacillus rhamnosus GG is able to bind the potent hepatocarcinogen aflatoxin B1 (AFB1) and thus potentially restrict its rapid absorption from the intestine. In this study we investigated the potential of GG to reduce AFB1 availability in vitro in Caco-2 cells adapted to express cytochrome P-450 (CYP) 3A4, such that both transport and toxicity could be assessed. Caco-2 cells were grown as confluent monolayers on transmembrane filters for 21 days prior to all studies. AFB1 levels in culture medium were measured by high-performance liquid chromatography. In CYP 3A4-induced monolayers, AFB1 transport from the apical to the basolateral chamber was reduced from 11.1% ± 1.9% to 6.4% ± 2.5% (P = 0.019) and to 3.3% ± 1.8% (P = 0.002) within the first hour in monolayers coincubated with GG (1 × 1010 and 5 × 1010 CFU/ml, respectively). GG (1 × 1010 and 5 × 1010 CFU/ml) bound 40.1% ± 8.3% and 61.0% ± 6.0% of added AFB1 after 1 h, respectively. AFB1 caused significant reductions of 30.1% (P = 0.01), 49.4% (P = 0.004), and 64.4% (P < 0.001) in transepithelial resistance after 24, 48, and 72 h, respectively. Coincubation with 1 × 1010 CFU/ml GG after 24 h protected against AFB1-induced reductions in transepithelial resistance at both 24 h (P = 0.002) and 48 h (P = 0.04). DNA fragmentation was apparent in cells treated only with AFB1 cells but not in cells coincubated with either 1 × 1010 or 5 × 1010 CFU/ml GG. GG reduced AFB1 uptake and protected against both membrane and DNA damage in the Caco-2 model. These data are suggestive of a beneficial role of GG against dietary exposure to aflatoxin. PMID:17449679

  6. Dietary aflatoxin exposure and impaired growth in young children from Kisumu District, Kenya: Cross sectional study.

    PubMed

    Okoth, Sheila Adhiambo; Ohingo, Mercy

    2004-01-01

    Cereal grains are the basis of weaning gruel in Kenya yet they run a high risk of mycotoxin contamination. Children could be at a higher risk of dietary mycotoxin exposure than the rest of the population. This paper presents information on the association between nutritional state of children and dietary exposure to aflatoxins in Kisumu District. Weaning flour samples were collected randomly from 242 households in Kisumu District, Kenya. A questionnaire was used to collect information, from mothers whose flour were sampled, on the types of weaning foods, handling and storage. The nutritional status of the children in question was assessed and their weight and height measured. The flour samples were analyzed for aflatoxins by thin layer chromatography. Cultural studies of the flour were also done. Thirty one percent of the children were malnourished. The number of children who were wasting and were being fed on flour contaminated with mycotoxins was highly significant (P = 0.002). Seventy samples (29 %) were positive for aflatoxins (concentration range 2-82 mg / kg), some exceeding the advisory limit.

  7. The Molecular Epidemiology of Chronic Aflatoxin Driven Impaired Child Growth

    PubMed Central

    Turner, Paul Craig

    2013-01-01

    Aflatoxins are toxic secondary fungal metabolites that contaminate dietary staples in tropical regions; chronic high levels of exposure are common for many of the poorest populations. Observations in animals indicate that growth and/or food utilization are adversely affected by aflatoxins. This review highlights the development of validated exposure biomarkers and their use here to assess the role of aflatoxins in early life growth retardation. Aflatoxin exposure occurs in utero and continues in early infancy as weaning foods are introduced. Using aflatoxin-albumin exposure biomarkers, five major studies clearly demonstrate strong dose response relationships between exposure in utero and/or early infancy and growth retardation, identified by reduced birth weight and/or low HAZ and WAZ scores. The epidemiological studies include cross-sectional and longitudinal surveys, though aflatoxin reduction intervention studies are now required to further support these data and guide sustainable options to reduce the burden of exposure. The use of aflatoxin exposure biomarkers was essential in understanding the observational data reviewed and will likely be a critical monitor of the effectiveness of interventions to restrict aflatoxin exposure. Given that an estimated 4.5 billion individuals live in regions at risk of dietary contamination the public health concern cannot be over stated. PMID:24455429

  8. Application of Probabilistic Modeling to Quantify the Reduction Levels of Hepatocellular Carcinoma Risk Attributable to Chronic Aflatoxins Exposure.

    PubMed

    Wambui, Joseph M; Karuri, Edward G; Ojiambo, Julia A; Njage, Patrick M K

    2017-01-01

    Epidemiological studies show a definite connection between areas of high aflatoxin content and a high occurrence of human hepatocellular carcinoma (HCC). Hepatitis B virus in individuals further increases the risk of HCC. The two risk factors are prevalent in rural Kenya and continuously predispose the rural populations to HCC. A quantitative cancer risk assessment therefore quantified the levels at which potential pre- and postharvest interventions reduce the HCC risk attributable to consumption of contaminated maize and groundnuts. The assessment applied a probabilistic model to derive probability distributions of HCC cases and percentage reductions levels of the risk from secondary data. Contaminated maize and groundnuts contributed to 1,847 ± 514 and 158 ± 52 HCC cases per annum, respectively. The total contribution of both foods to the risk was additive as it resulted in 2,000 ± 518 cases per annum. Consumption and contamination levels contributed significantly to the risk whereby lower age groups were most affected. Nonetheless, pre- and postharvest interventions might reduce the risk by 23.0-83.4% and 4.8-95.1%, respectively. Therefore, chronic exposure to aflatoxins increases the HCC risk in rural Kenya, but a significant reduction of the risk can be achieved by applying specific pre- and postharvest interventions.

  9. [Cost-benefit analysis in setting up limitation standards of aflatoxins in foods].

    PubMed

    Wang, Jun; Liu, Xiumei

    2011-03-01

    To explore a reasonable limitation standard for aflatoxins in foods to protect the health of people in China with a cost-benefit analysis. A traditional mathematical model and MOE (margin of exposure) method was used to assess the effect of different limiting standards on health for total aflatoxins and aflatoxin B1 in peanut, corn and rice, and the loss of foods under different limiting standard levels was also calculated. The change of limiting standards for total aflatoxins and aflatoxin B1 in peanut and corn might have no significant influence on reducing the prevalence of liver cancer in China, but the loss of foods was significantly different. The change of limiting standards for total aflatoxins and aflatoxin B1 in ice might have significant influence both on reducing liver cancer and losing foods. The following limiting standards is advisable: 20 microg/kg for total aflatoxins and 15 microg/kg for Aflatoxin B1 in peanut and its products, 20 microg/kg for total aflatoxins and 15 microg/kg for aflatoxin B1 in corn, 10 microg/kg for total aflatoxins and 5 microg/kg or 10 microg/kg for aflatoxin B1 in rice.

  10. Determination of urinary biomarkers for assessment of short-term human exposure to aflatoxins in São Paulo, Brazil.

    PubMed

    Jager, Alessandra V; Tonin, Fernando G; Souto, Pollyana C M C; Privatti, Rafaela T; Oliveira, Carlos A F

    2014-07-08

    In the present study, a longitudinal assessment was carried out to evaluate the short-term human exposure to aflatoxins in Pirassununga region, São Paulo, Brazil, by determination of urinary aflatoxins by a liquid chromatography coupled to mass sprectrometry (UPLC-MS/MS) method. Sixteen volunteers with ages ranging from 14 to 55 years old were instructed to collect the early morning first urine four times every three months, from June 2011 to March 2012, totaling 64 samples. Aflatoxin M1 (AFM1) was found in 39 samples (61%) at levels ranging from 0.19 to 12.7 pg·mg-1 creatinine (mean: 1.2 ± 2.0 pg·mg-1 creatinine). Residues of aflatoxins B1, B2, G1, G2 and aflatoxicol were not identified in any urine sample. No significant difference was found among the AFM1 mean levels in urine samples collected in the four sampling periods. The levels of AFM1 found in urine samples indicate a low short-term exposure of the population studied to aflatoxins through the diet, although further investigations are needed to assess other long-term biomarkers of exposure to AFB1.

  11. Determination of Urinary Biomarkers for Assessment of Short-Term Human Exposure to Aflatoxins in São Paulo, Brazil

    PubMed Central

    Jager, Alessandra V.; Tonin, Fernando G.; Souto, Pollyana C. M. C.; Privatti, Rafaela T.; Oliveira, Carlos A. F.

    2014-01-01

    In the present study, a longitudinal assessment was carried out to evaluate the short-term human exposure to aflatoxins in Pirassununga region, São Paulo, Brazil, by determination of urinary aflatoxins by a liquid chromatography coupled to mass sprectrometry (UPLC-MS/MS) method. Sixteen volunteers with ages ranging from 14 to 55 years old were instructed to collect the early morning first urine four times every three months, from June 2011 to March 2012, totaling 64 samples. Aflatoxin M1 (AFM1) was found in 39 samples (61%) at levels ranging from 0.19 to 12.7 pg·mg−1 creatinine (mean: 1.2 ± 2.0 pg·mg−1 creatinine). Residues of aflatoxins B1, B2, G1, G2 and aflatoxicol were not identified in any urine sample. No significant difference was found among the AFM1 mean levels in urine samples collected in the four sampling periods. The levels of AFM1 found in urine samples indicate a low short-term exposure of the population studied to aflatoxins through the diet, although further investigations are needed to assess other long-term biomarkers of exposure to AFB1. PMID:25007123

  12. Determination of aflatoxin M1 in breast milk as a biomarker of maternal and infant exposure in Colombia.

    PubMed

    Diaz, Gonzalo J; Sánchez, Marlib Paloma

    2015-01-01

    Chronic exposure to aflatoxins, and especially to aflatoxin B1 (AFB1), causes hepatocellular carcinoma with prevalence 16-32 times higher in developing compared with developed countries. Aflatoxin M1 (AFM1) is a monohydroxylated metabolite from AFB1 that is secreted in milk and which can be used as a biomarker of AFB1 exposure. This study aimed to determine AFM1 levels in human breast milk using immunoaffinity column clean-up with HPLC and fluorescence detection. Breast milk samples were obtained from 50 nursing mothers. Volunteers filled in a questionnaire giving their consent to analyse their samples as well as details of their socioeconomic, demographic and clinical data. The possible dietary sources of aflatoxins were assessed using a food frequency questionnaire. A total of 90% of the samples tested positive for AFM1, with a mean of 5.2 ng l(-1) and a range of 0.9-18.5 ng l(-1). The study demonstrated a high frequency of exposure of mothers and neonates to AFB1 and AFM1 in Colombia, and it points out the need to regulate and monitor continuously the presence of aflatoxins in human foods. Further research is needed in order to determine the presence of other mycotoxins in foods and in human samples as well as to devise protection strategies in a country where mycotoxins in human foods are commonly found.

  13. Global hypomethylation in hepatocellular carcinoma and its relationship to aflatoxin B1 exposure

    PubMed Central

    Zhang, Yu-Jing; Wu, Hui-Chen; Yazici, Hulya; Yu, Ming-Whei; Lee, Po-Huang; Santella, Regina M

    2012-01-01

    AIM: To determine global DNA methylation in paired hepatocellular carcinoma (HCC) samples using several different assays and explore the correlations between hypomethylation and clinical parameters and biomarkers, including that of aflatoxin B1 exposure. METHODS: Using the radio labeled methyl acceptance assay as a measure of global hypomethylation, as well as two repetitive elements, including satellite 2 (Sat2) by MethyLight and long interspersed nucleotide elements (LINE1), by pyrosequencing. RESULTS: By all three assays, mean methylation levels in tumor tissues were significantly lower than that in adjacent tissues. Methyl acceptance assay log (mean ± SD) disintegrations/min/ng DNA are 70.0 ± 54.8 and 32.4 ± 15.6, respectively, P = 0.040; percent methylation of Sat2 42.2 ± 55.1 and 117.9 ± 88.8, respectively, P < 0.0001 and percent methylation LINE1 48.6 ± 14.8 and 71.7 ± 1.4, respectively, P < 0.0001. Aflatoxin B1-albumin (AFB1-Alb) adducts, a measure of exposure to this dietary carcinogen, were inversely correlated with LINE1 methylation (r = -0.36, P = 0.034). CONCLUSION: Consistent hypomethylation in tumor compared to adjacent tissue was found by the three different methods. AFB1 exposure is associated with DNA global hypomethylation, suggesting that chemical carcinogens may influence epigenetic changes in humans. PMID:22666524

  14. Determinants of recent aflatoxin exposure among pregnant women in rural Zimbabwe.

    PubMed

    Smith, Laura E; Mbuya, Mduduzi N N; Prendergast, Andrew J; Turner, Paul C; Ruboko, Sandra; Humphrey, Jean H; Nelson, Rebecca J; Chigumira, Ancikaria; Kembo, George; Stoltzfus, Rebecca J

    2017-09-01

    Aflatoxins (AFs) are toxic secondary metabolites of Aspergillus species that contaminate staple foods such as maize and groundnuts. AF exposure during pregnancy has been associated with adverse birth outcomes in limited-scale surveys in sub-Saharan Africa. The objective of this study was to describe the determinants of AF exposure, using urinary aflatoxin M1 (AFM1) biomarkers and data generated by the Sanitation Hygiene Infant Nutrition Efficacy (SHINE) trial for rural Zimbabwean women in early pregnancy. Sanitation Hygiene Infant Nutrition Efficacy is a large, cluster-randomized community-based trial in Zimbabwe designed to investigate the independent and combined effects of nutrition and hygiene interventions on early child growth. Urine samples collected from 1580 pregnant women in rural Zimbabwe at median gestational age of 13.9 wk were measured for AFM1. AFM1 was detected in 30% of samples (median of exposed, 162 pg AFM1/mg creatinine; range 30-6046 pg AFM1/mg). In multivariable ordinal logistic models, geographical location (p<0.001), seasonality (p < 0.001) and dietary practices (p = 0.011) were significant predictors of urinary AFM1. This is the largest AF biomarker survey conducted in Zimbabwe, and demonstrated frequent exposure in pregnant women with clear temporal and spatial variability in AF biomarker levels. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Ecology of Aspergillus flavus, Regulation of Aflatoxin Production and Management Strategies to Reduce Aflatoxin Contamination of Corn

    USDA-ARS?s Scientific Manuscript database

    The contamination of corn (maize) by fungi and the accumulation of mycotoxins are a serious agricultural problem for human and animal health. One particular devastating group of mycotoxins, called aflatoxins, has been intensely studied since the 1960s. Studies of Aspergillus flavus, the agricultura...

  16. Dietary Exposure and Natural Occurrence of Total Aflatoxins in Basmati Rice of Pakistan.

    PubMed

    Sultana, Nighat; Tahira, Iffat; Kausar, Mumtaz; Hassan, Syed Mujahid; Hanif, Nafeesa Qudsia

    2017-02-01

    This study presents the assessment of total aflatoxins (TAFs) in basmati rice (brown, 1,081; white, 1,170) collected from different areas of Punjab, Pakistan, during 2010 to 2015. Due to the carcinogenicity of TAFs, daily dietary exposure is also evaluated based on rice consumption survey data. Methodology was standardized by matrix spike recoveries at four fortification levels (0.1, 0.5, 2.5, and 12.5 ng/g) for TAFs (aflatoxins B1 [AFB1], B2 [AFB2], G1 [AFG1], and G2 [AFG2]). The present study reveals that 1,750 samples (77.74%) were tainted with AFB1, whereas TAFs were detected in 370 samples (16.43%). Of positive samples, 854 brown rice samples (79%) were positive for AFB1, and 154 samples (14.24%) were contaminated with TAFs. For white rice, 896 samples (76.58%) were contaminated with AFB1, whereas 205 samples (18.46%) were found positive for TAFs. Study findings were used to construct a frequency distribution, and AFB1 levels were also compared against permissible levels of TAFs (10 ng/g) as legislated by the European Commission. Results further revealed that daily dietary exposure of TAFs ranged from 0.51 to 10.22 ng/kg of body weight per day, which exceeds the permissible limit of 1 ng/kg of body weight per day as defined by the Joint FAO/WHO Expert Committee on Food Additives.

  17. Influences of climate on aflatoxin producing fungi and aflatoxin contamination.

    PubMed

    Cotty, Peter J; Jaime-Garcia, Ramon

    2007-10-20

    Aflatoxins are potent mycotoxins that cause developmental and immune system suppression, cancer, and death. As a result of regulations intended to reduce human exposure, crop contamination with aflatoxins causes significant economic loss for producers, marketers, and processors of diverse susceptible crops. Aflatoxin contamination occurs when specific fungi in the genus Aspergillus infect crops. Many industries frequently affected by aflatoxin contamination know from experience and anecdote that fluctuations in climate impact the extent of contamination. Climate influences contamination, in part, by direct effects on the causative fungi. As climate shifts, so do the complex communities of aflatoxin-producing fungi. This includes changes in the quantity of aflatoxin-producers in the environment and alterations to fungal community structure. Fluctuations in climate also influence predisposition of hosts to contamination by altering crop development and by affecting insects that create wounds on which aflatoxin-producers proliferate. Aflatoxin contamination is prevalent both in warm humid climates and in irrigated hot deserts. In temperate regions, contamination may be severe during drought. The contamination process is frequently broken down into two phases with the first phase occurring on the developing crop and the second phase affecting the crop after maturation. Rain and temperature influence the phases differently with dry, hot conditions favoring the first and warm, wet conditions favoring the second. Contamination varies with climate both temporally and spatially. Geostatistics and multiple regression analyses have shed light on influences of weather on contamination. Geostatistical analyses have been used to identify recurrent contamination patterns and to match these with environmental variables. In the process environmental conditions with the greatest impact on contamination are identified. Likewise, multiple regression analyses allow ranking of

  18. Co-exposure to fumonisins and aflatoxins in maize-based foods in central america: guatemala as a case study

    USDA-ARS?s Scientific Manuscript database

    Aflatoxin B1 (AFB1) is a human liver carcinogen having a genotoxic mechanism of action. The ceramide synthase inhibitor fumonisin B1 (FB1) is a liver cancer promoter in rats and trout. Both mycotoxins are found in maize so that the possibility of co-exposure is a health concern, especially in Centra...

  19. Prenatal exposure to aflatoxin B1: developmental, behavioral, and reproductive alterations in male rats

    NASA Astrophysics Data System (ADS)

    Supriya, Ch.; Reddy, P. Sreenivasula

    2015-06-01

    Previous studies have shown that aflatoxin B1 (AfB1) inhibits androgen biosynthesis as a result of its ability to form a high-affinity complex with the steroidogenic acute regulatory protein. The results of the present study demonstrate the postnatal effects of in utero exposure to AfB1 in the rat. Pregnant Wistar rats were given 10, 20, or 50 μg AfB1/kg body weight daily from gestation day (GD) 12 to GD 19. At parturition, newborns were observed for clinical signs and survival. All animals were born alive and initially appeared to be active. Male pups from control and AfB1-exposed animals were weaned and maintained up to postnatal day (PD) 100. Litter size, birth weight, sex ratio, survival rate, and crown-rump length of the pups were significantly decreased in AfB1-exposed rats when compared to controls. Elapsed time (days) for testes to descend into the scrotal sac was significantly delayed in experimental pups when compared to control pups. Behavioral observations such as cliff avoidance, negative geotaxis, surface rightening activity, ascending wire mesh, open field behavior, and exploratory and locomotory activities were significantly impaired in experimental pups. Body weights and the indices of testis, cauda epididymis, prostate, seminal vesicles, and liver were significantly reduced on PD 100 in male rats exposed to AfB1 during embryonic development when compared with controls. Significant reduction in the testicular daily sperm production, epididymal sperm count, and number of viable, motile, and hypo-osmotic tail coiled sperm was observed in experimental rats. The levels of serum testosterone and activity levels of testicular hydroxysteroid dehydrogenases were significantly decreased in a dose-dependent manner with a significant increase in the serum follicle-stimulating hormone and luteinizing hormone in experimental rats. Deterioration in the testicular and cauda epididymal architecture was observed in experimental rats. The results of fertility

  20. The toxicology of aflatoxins as a basis for public health decisions.

    PubMed

    Wild, C P; Turner, P C

    2002-11-01

    Aflatoxins have been extensively studied with respect to their mechanisms of toxicity. An understanding of metabolism, DNA adduct induction, mutagenicity and carcinogenicity has been paralleled by the development of biomarkers of aflatoxin exposure and biological effects (e.g. mutations) applied to human populations. The improvements in exposure assessment and their application in prospective epidemiological studies and the demonstration of a specific mutation in the TP53 gene in hepatocellular carcinomas from areas of high aflatoxin exposure have contributed significantly to the classification of aflatoxins as human carcinogens. In addition to establishing the carcinogenicity of aflatoxins in humans, understanding molecular mechanisms of action has provided the scientific rationale for prevention strategies, including primary and chemoprevention approaches. Overall, integrated, multidisciplinary research on aflatoxins has provided the platform on which to base decisions regarding acceptable exposures and priorities for interventions to reduce human risk in a public health context.

  1. Effect of occupational exposure to aflatoxins on some liver tumor markers in textile workers.

    PubMed

    Saad-Hussein, Amal; Beshir, Safia; Moubarz, Gehan; Elserougy, Safaa; Ibrahim, Mohamed I M

    2013-07-01

    In a study of textile workers, the effects of occupational exposure to cotton dust-with possible exposure to aflatoxin-on levels of some liver tumor biomarkers were explored. The study included 58 textile workers and 64 controls. Skin prick tests, urinary Aflatoxin M1 (AFM1) and the tumor biomarkers (alpha-fetoprotein (AFP), alpha-L-fucosidase (AFU), insulin-like growth factors (IGF-1) were measured. Positive reactants to Aspergillus niger, Aspergillus flavus, and cotton dust were significantly higher in pre-spinning (14.3%, 28.6%, and 28.6%, respectively) and spinning workers (25.0%, 33.3%, and 25.0%, respectively) compared to controls (4.7%, 7.8%, and 3.1%, respectively). Urinary AFM1 was significantly higher in the pre-spinning, spinning, and weaving groups compared to controls (554.2 ± 346.2 pg/ml, 459.1 ± 781.6 pg/ml, 296.5 ± 336.5 pg/ml and 68.5 ± 136.8 pg/ml, respectively). We found a highly significant increase in levels of serum AFU in textile workers, compared to the control group. Exposure to fungi had a significant effect on AFM1 measurements and tumor biomarkers, especially in allergic textile workers (with the exception of the arginase biomarker), though results were generally within normal limits. Copyright © 2013 Wiley Periodicals, Inc.

  2. Association between aflatoxin B1 occupational airway exposure and risk of hepatocellular carcinoma: a case-control study.

    PubMed

    Lai, Hao; Mo, Xianwei; Yang, Yang; He, Ke; Xiao, Jun; Liu, Chao; Chen, Jiansi; Lin, Yuan

    2014-10-01

    The aim of this study was to determine the airway exposure of sugar and papermaking factory workers to aflatoxin B1 (AFB1) and to explore the potential association between AFB1 airway exposure and the risk of hepatocellular carcinoma (HCC) in a case-control study. Dust samples were collected from the sugarcane bagasse warehouse, and presser and paper production workshops. Blood samples were collected from 181 workshop employees and 203 controls who worked outside the workshop. AFB1 albumin adducts were detected using a double antibody sandwich enzyme-linked immunosorbent assay (ELISA). To explore the association between AFB1 airway exposure and the risk of HCC, the medical records of 68 HCC patients who worked in a sugar and papermaking factory between January 1994 and December 2013 were analyzed. A questionnaire was used to collect information from 150 healthy controls who worked for the same company and lived near the factory. AFB1 was detected in the dust samples, but could not be detected in any of the rice samples. An analysis of serum samples revealed serum AFB1 albumin adducts in 102 (56.35 %) of the study participants. However, in the control group, only 12 (5.9 %) individuals had detectable levels of AFB1 albumin adducts. Those with airway exposure to Aspergillus flavus-contaminated dust had an elevated risk of HCC compared to those without exposure (odds ratio, 5.24; 95 % confidence interval, 2.77-9.88; P = 0.00). The findings of this study indicate that occupational AFB1 airway exposure might be associated with the risk of AFB1-related HCC among the population that was used in this study. Intervention programs aimed at reducing exposure to inhalational AFB1 are needed urgently. Additional suitably designed, multicenter, prospective studies using large samples are needed to further confirm the results.

  3. [Longitudinal study of aflatoxin exposure in the development of primary liver cancer in patients with chronic hepatitis].

    PubMed

    Lu, Pei-xin; Wang, Jin-bing; Zhang, Qi-nan; Wu, Yan; Sun, Yan; Chen, Tao-yang

    2010-06-22

    To study the relationship between aflatoxin exposure and the development of primary liver cancer (PLC) in patients with chronic hepatitis. A 21-year longitudinal study was carried out in a large cohort of 515 PLC high-risk individuals with HBV infection in PLC high prevalence region. (1) The PLC year-incidence of cohort was 1437.25/100,000. And it was significantly higher than that of the same natural peoples (184. 53/100,000, P = 0.000, RR = 7.79). There was no significant difference in the incidence of other tumors between these two groups (P = 0.576). (2) The PLC patients in the cohort were diagnosed at an average age 1.4 year younger than those in the same natural peoples and had an average survival of 6.42 months longer than the latter. (3) The PLC year-incidence of those with the exposure to aflatoxin was significantly higher than that of unexposed people (2784. 96/100,000 vs. 1251.02/100,000, P = 0.008, RR = 2.23). There was no relationship between the incidence rate of other tumors and the aflatoxin exposure. (4) The PLC year-incidence of aflatoxin-exposing people increased with the rising urine excretion of AFM1. When the urine excretion of AFM1 was more than 100 ng during 24 hours, the PLC year-incidence was high as 4717.82/100,000. The urine excretion of AFM1 was also obviously related with the abnormal liver function (P = 0.035). There was no relationship with the positive rate of HBeAg (P = 0.812). (5) The PLC year-incidence of those with the exposure to aflatoxin were infected with HBV (2 784. 96/100 000) significantly higher than that of cohort people (P = 0.001) and the same natural peoples (P = 0.000, RR = 15.09). (6) It took an average time of 14.65 years (median 13.68) from hepatitis occurrence to PLC diagnosis and 7.38 years (median 6.40) from liver cirrhosis to PLC diagnosis. HBV infection is a main etiological factor of PLC and the aflatoxin exposure has obvious synergistic effect in the carcinogenesis of PLC. Regular observation in a PLC high

  4. Risk Assessment on Dietary Exposure to Aflatoxin B₁ in Post-Harvest Peanuts in the Yangtze River Ecological Region.

    PubMed

    Ding, Xiaoxia; Wu, Linxia; Li, Peiwu; Zhang, Zhaowei; Zhou, Haiyan; Bai, Yizhen; Chen, Xiaomei; Jiang, Jun

    2015-10-15

    Based on the 2983 peanut samples from 122 counties in six provinces of China's Yangtze River ecological region collected between 2009-2014, along with the dietary consumption data in Chinese resident nutrition and health survey reports from 2002 and 2004, dietary aflatoxin exposure and percentiles in the corresponding statistics were calculated by non-parametric probability assessment, Monte Carlo simulation and bootstrap sampling methods. Average climatic conditions in the Yangtze River ecological region were calculated based on the data from 118 weather stations via the Thiessen polygon method. The survey results found that the aflatoxin contamination of peanuts was significantly high in 2013. The determination coefficient (R²) of multiple regression reflected by the aflatoxin B₁ content with average precipitation and mean temperature in different periods showed that climatic conditions one month before harvest had the strongest impact on aflatoxin B₁ contamination, and that Hunan and Jiangxi provinces were greatly influenced. The simulated mean aflatoxin B₁ intake from peanuts at the mean peanut consumption level was 0.777-0.790 and 0.343-0.349 ng/(kg·d) for children aged 2-6 and standard adults respectively. Moreover, the evaluated cancer risks were 0.024 and 0.011/(100,000 persons·year) respectively, generally less than China's current liver cancer incidence of 24.6 cases/(100,000 persons·year). In general, the dietary risk caused by peanut production and harvest was low. Further studies would focus on the impacts of peanut circulation and storage on aflatoxin B₁ contamination risk assessment in order to protect peanut consumers' safety and boost international trade.

  5. Risk Assessment on Dietary Exposure to Aflatoxin B1 in Post-Harvest Peanuts in the Yangtze River Ecological Region

    PubMed Central

    Ding, Xiaoxia; Wu, Linxia; Li, Peiwu; Zhang, Zhaowei; Zhou, Haiyan; Bai, Yizhen; Chen, Xiaomei; Jiang, Jun

    2015-01-01

    Based on the 2983 peanut samples from 122 counties in six provinces of China’s Yangtze River ecological region collected between 2009–2014, along with the dietary consumption data in Chinese resident nutrition and health survey reports from 2002 and 2004, dietary aflatoxin exposure and percentiles in the corresponding statistics were calculated by non-parametric probability assessment, Monte Carlo simulation and bootstrap sampling methods. Average climatic conditions in the Yangtze River ecological region were calculated based on the data from 118 weather stations via the Thiessen polygon method. The survey results found that the aflatoxin contamination of peanuts was significantly high in 2013. The determination coefficient (R2) of multiple regression reflected by the aflatoxin B1 content with average precipitation and mean temperature in different periods showed that climatic conditions one month before harvest had the strongest impact on aflatoxin B1 contamination, and that Hunan and Jiangxi provinces were greatly influenced. The simulated mean aflatoxin B1 intake from peanuts at the mean peanut consumption level was 0.777–0.790 and 0.343–0.349 ng/(kg·d) for children aged 2–6 and standard adults respectively. Moreover, the evaluated cancer risks were 0.024 and 0.011/(100,000 persons·year) respectively, generally less than China’s current liver cancer incidence of 24.6 cases/(100,000 persons·year). In general, the dietary risk caused by peanut production and harvest was low. Further studies would focus on the impacts of peanut circulation and storage on aflatoxin B1 contamination risk assessment in order to protect peanut consumers’ safety and boost international trade. PMID:26501322

  6. Occupational exposure to aflatoxin B1 in swine production and possible contamination sources.

    PubMed

    Viegas, Susana; Veiga, Luísa; Figueredo, Paula; Almeida, Ana; Carolino, Elisabete; Sabino, Raquel; Veríssimo, Cristina; Viegas, Carla

    2013-01-01

    Although the adverse health consequences of ingestion of food contaminated with aflatoxin B1 (AFB1) are known, relatively few studies are available on the adverse effects of exposure in occupational settings. Taking this into consideration, our study was developed aiming to elucidate the possible effects of occupational exposure to AFB1 in Portuguese swine production facilities using a specific biomarker to assess exposure to AFB1. In total, 28 workers participated in this study, providing blood samples, and a control group (n = 30) was composed of subjects without any type of agricultural activity. Fungal contamination was also studied by conventional methods through air, surfaces, and new and used floor coverage. Twenty-one workers (75%) showed detectable levels of AFB1 with values ranging from <1 ng/ml to 8.94 ng/ml and with a mean value of 1.91 ± 1.68 ng/ml. In the control group, the AFB1 values were all below 1 ng/ml. Twelve different Aspergillus species were identified. Aspergillus versicolor presented the highest airborne spore counts (3210 CFU/m3) and was also detected in higher values in surfaces (>300 CFU/cm2). Data indicate that exposure to AFB1 occurs in swine barns, and this site serves as a contamination source in an occupational setting.

  7. Molecular dosimetry in fish: quantitative target organ DNA adduction and hepatocarcinogenicity for four aflatoxins by two exposure routes in rainbow trout.

    PubMed

    Bailey, G S; Dashwood, R; Loveland, P M; Pereira, C; Hendricks, J D

    1998-03-20

    Rainbow trout, a species highly sensitive to aflatoxins, was used to investigate the relative carcinogenicities of four structurally related aflatoxins in terms of their target organ DNA binding characteristics. Tritiated syntheses were carried out, DNA binding dose-response curves were established, and liver DNA binding indices were calculated for the four aflatoxins following a 2-week dietary fry exposure protocol. The results indicated that adduct levels increased linearly with dietary dose concentration, with relative DNA binding indices of 20.7, 20.3, 2.35, and 2.22 x 10(3) (pmoles aflatoxin mg-1 DNA)/(pmoles aflatoxin g-1 diet) for aflatoxin B1 (AFB1), aflatoxicol (AFL), aflatoxin M1 (AFM1), and aflatoxicol M1 (AFLM1), respectively. A similar protocol used over 7200 trout fry averaging 1.2 g initial body weight to establish full carcinogen dose-response curves for each aflatoxin, along with a single-dose estimate of DNA binding index within the tumor study animals. Owing to trout sensitivity a total of 180 micrograms or less of each aflatoxin was required. Data analyzed on logit incidence vs. Ln dose coordinates generated four curves which were modeled as parallel in slope over most or all dose ranges studied. By this analysis, relative tumorigenic potencies were: AFB1 1.00; AFL 0.936; AFM1 0.086; and AFLM1 0.041. When data were plotted as logit incidence vs. Ln adducts (effective dose received), all aflatoxin adducts described the same dose-response curve; that is, they were equally tumorigenic, except those from AFLM1, which were 2-3 fold less potent. Therefore, by these molecular dose studies, differences in tumorigenicity among the four dietary aflatoxins are largely or entirely accounted for by differences in uptake and metabolism leading to DNA adduction, rather than any inherent differences in tumor initiating potency per DNA adduct.

  8. Calcium montmorillonite clay in dairy feed reduces aflatoxin concentrations in milk without interfering with milk quality, composition or yield

    USDA-ARS?s Scientific Manuscript database

    This study was designed to determine if a calcium montmorillonite clay (Novasil Plus, NSP), can significantly reduce aflatoxin M1 (AFM1) concentrations in milk without affecting dry matter intake (DMI), milk yield, milk composition, vitamin A, or riboflavin concentrations. The study was designed us...

  9. The association between exposure to aflatoxin, mutation in TP53, infection with hepatitis B virus, and occurrence of liver disease in a selected population in Hyderabad, India.

    PubMed

    Anitha, S; Raghunadharao, D; Waliyar, F; Sudini, H; Parveen, M; Rao, Ratna; Kumar, P Lava

    2014-05-15

    Aflatoxin B1 is a carcinogen produced by Aspergillus flavus and a few related fungi that are often present in many food substances. It interacts synergistically with Hepatitis B or C virus (HBV, HBC) infection, thereby increasing the risk of hepatocellular carcinoma (HCC). The G to T transversion at the third position of codon 249 (AGG) of the TP53 gene, substituting arginine to serine, is the most common aflatoxin-induced mutation linked to HCC. This study examined mutations in TP53 by PCR-RFLP analysis and by measurement of an aflatoxin-albumin adduct as a biomarker for human exposure of aflatoxin B1 by indirect-competitive ELISA, in samples collected from healthy controls as well as patients with hepatitis in Hyderabad, Andhra Pradesh, India. A total of 238 blood samples were analyzed the presence of the G to T mutation. Eighteen of these samples were from HBV-positive subjects, 112 of these were from subjects who had HBV-induced liver cirrhosis, and 108 samples were taken from subjects without HBV infection or liver cirrhosis (control group). The G to T mutation was detected in 10 samples, 8 of which were from subjects positive to both HBV and aflatoxin-albumin adduct in blood (p=0.07); whilst two were from individuals who were HBV-negative, but positive for the aflatoxin-albumin adduct (p=0.14). The aflatoxin-albumin adduct was detected in 37 of 238 samples, 29 samples were from HBV-positive subjects and eight were from individuals who were positive for both HBV and the TP53 mutation (p=0.07). The concentration of aflatoxin-albumin adduct ranged from 2.5 to 667pg/mg albumin. Despite low incidence of the G to T mutation, its detection in subjects positive to aflatoxin-adducts is indicative of a strong association between the mutation and aflatoxin exposure in India.

  10. Use of Cold Atmospheric Plasma to Detoxify Hazelnuts from Aflatoxins

    PubMed Central

    Siciliano, Ilenia; Spadaro, Davide; Prelle, Ambra; Vallauri, Dario; Cavallero, Maria Chiara; Garibaldi, Angelo; Gullino, Maria Lodovica

    2016-01-01

    Aflatoxins, produced by Aspergillus flavus and A. parasiticus, can contaminate different foodstuffs, such as nuts. Cold atmospheric pressure plasma has the potential to be used for mycotoxin detoxification. In this study, the operating parameters of cold atmospheric pressure plasma were optimized to reduce the presence of aflatoxins on dehulled hazelnuts. First, the effect of different gases was tested (N2, 0.1% O2 and 1% O2, 21% O2), then power (400, 700, 1000, 1150 W) and exposure time (1, 2, 4, and 12 min) were optimized. In preliminary tests on aflatoxin standard solutions, this method allowed to obtain a complete detoxification using a high power for a few minutes. On hazelnuts, in similar conditions (1000 W, 12 min), a reduction in the concentration of total aflatoxins and AFB1 of over 70% was obtained. Aflatoxins B1 and G1 were more sensitive to plasma treatments compared to aflatoxins B2 and G2, respectively. Under plasma treatment, aflatoxin B1 was more sensitive compared to aflatoxin G1. At the highest power, and for the longest time, the maximum temperature increment was 28.9 °C. Cold atmospheric plasma has the potential to be a promising method for aflatoxin detoxification on food, because it is effective and it could help to maintain the organoleptic characteristics. PMID:27128939

  11. Monitoring of individual human exposure to aflatoxins (AF) and N-nitrosamines (NNO) by immunoassays

    SciTech Connect

    Wild, C.P.; Umbenhauer, D.; Chapot, B.; Montesano, R.

    1986-01-01

    Highly sensitive immunoassays have been used to quantitate aflatoxins (AF) and N-nitrosamines (NNO) in human body fluids and tissues, respectively. This approach was taken in order to quantitate environmental exposure to these agents at an individual level to facilitate the investigation of their role in the etiology of human cancer. In order to analyse AF in human urine, an immunopurification step has been developed by using AF-specific antibody bound to AH-Sepharose 4B gel in a small (4-ml gel volume) affinity column prior to enzyme-linked immunosorbent assay (ELISA). The ELISA can be used to quantitate aflatoxin B1 (AFB1) over the range 0.01 ng/ml to 10 ng/ml and the assay system has been validated by using human urine samples spiked with AFB1 over this concentration range. In addition, 29 urine samples from the Philippines have been analyzed and found to contain a range of levels from zero to 4.25 ng/ml AFB1 equivalent with a mean of 0.875 ng/ml. This compared with a mean of 0.066 ng/ml AFB1 equivalent in samples from France. Radioimmunoassay of O6-methyldeoxyguanosine (O6-medG) has been performed on human esophageal and cardiac stomach mucosal DNA from tissue samples obtained during surgery in Linxian County, People's Republic of China, an area of high risk for both esophageal and stomach cancer. Using the methodology described and having 1 mg of hydrolyzed DNA allows the detection of approximately 25 fmol O6medG per mg DNA.

  12. Biological Controls for Aflatoxin Reduction

    USDA-ARS?s Scientific Manuscript database

    Aflatoxin exposure is frequent and widespread in most African countries where the key staples, maize and groundnut, are particularly vulnerable to aflatoxin contamination. Aflatoxin-producing fungi are ubiquitous in Africa where they occupy soil and colonize diverse organic matter while producing sp...

  13. Efficacy and permanency of ammonia treatment in reducing aflatoxin levels in corn.

    PubMed

    Weng, C Y; Martinez, A J; Park, D L

    1994-01-01

    Naturally contaminated yellow corn containing 12500 ng/g of aflatoxin B1 (AFB1) was ground and blended with non-contaminated corn to obtain various levels of AFB1 (7500, 6300, 400, 354, and 17 ng AFB1/g). All samples were exposed to ammonia treatment under various conditions for 60 min. Treatment variables included ammonia concentration, moisture level of the corn, temperature, and pressure applied. The moisture content of the corn (8%) was adjusted to 12% and 16%, respectively. Four ammonia treatments were conducted for each moisture level: (a) 1.5% and 2.0% gaseous NH3 at 40-45 degrees C and 55 psi; (b) aqueous NH4OH (2.0% as NH3) at 121 degrees C and 17 psi; (c) sequential treatment of (a) and (b); and (d) aqueous NH4OH (2.0% as NH3) at 25 degrees C and 55 psi. For the treatment with 2% gaseous NH3, the reduction in levels of AFB1 in samples containing 12% moisture ranged from 52.7 to 67.7%, while in samples containing 16% moisture, the reduction ranged from 79.4 to 93.1%. Treatment with NH4OH alone at elevated temperatures (b) or following gaseous NH3 treatment (c) resulted in a reduction of the AFB1 content by greater than 99%. Treatment with NH4OH at 25 degrees C (d) showed a lower efficiency in reducing AFB1 levels. The permanency of the process, i.e. reversion of inactivated AFB1 to the parent compound, was studied by exposing the ammonia-treated corn to HCl (pH = 2.0 at 37 degrees C for 2 h) to simulate stomach acidity. The results showed no significant reversion of aflatoxin (reversibility less than 0.05%). These findings suggest that at high temperature aqueous NH4OH or gaseous NH3 can be used effectively to reduce AFB1 in corn. The present study also revealed that the moisture level of the product and holding temperature were the crucial factors that influenced the efficacy of aflatoxin decontamination by ammoniation.

  14. Quantitative trait loci (QTL) for reducing Aspergillus flavus infection and aflatoxin accumulation in corn

    USDA-ARS?s Scientific Manuscript database

    Aflatoxin produced by Aspergillus flavus in corn poses significant health risks for both humans and livestock. Corn growers suffer huge economic losses due to increased aflatoxin accumulation in grain especially under drought and higher temperature stress conditions. Exploitation of host plant resi...

  15. RNA interference reduces aflatoxin accumulation by Aspergillus flavus in peanut seeds

    USDA-ARS?s Scientific Manuscript database

    Aflatoxins are among the most powerful carcinogens in nature. They are produced by the fungal pathogen Aspergillus flavus Link and other Aspergillus species. Aflatoxins accumulate in many crops, including rice, wheat, oats, pecans, pistachios, soybean, cassava, almonds, peanuts, beans, corn and cot...

  16. Non-aflatoxigenic Aspergillus flavus isolates reduce aflatoxins, cyclopiazonic acid and fumonisin in corn (maize)

    USDA-ARS?s Scientific Manuscript database

    Aspergillus flavus strains vary widely in their production of aflatoxins and cyclopiazonic acid (CPA). A total of 500 Aspergillus strains isolated from a variety of sources showed 16.4% were negative for both aflatoxin and CPA, 41.3% were positive for both mycotoxins, 13.0% were positive only fo...

  17. Development of a gene - based marker correlated to reduced aflatoxin accumulation in maize

    USDA-ARS?s Scientific Manuscript database

    Aflatoxins are carcinogenic and toxic metabolites produced by the fungus Aspergillus flavus during infection of maize (Zea mays L.) and other seed oil crops. Climatic conditions in the southeastern United States favor A. flavus infection and aflatoxin contamination in maize, making it a major issue...

  18. Aflatoxin exposure may not play a role in liver cancer development in Mongolia.

    PubMed

    Popp, Walter; Gantumur, Tsagaan; Ross, Birgit; Zorigt, Khand; Davaadorj, Duger; Rossburg, Michael; Sowa, Jan-Peter; Canbay, Ali

    2014-01-01

    The incidence of hepatocellular carcinoma (HCC) in Mongolia is growing at an alarming rate. Traditional dried food was suggested as the major reason for high HCC numbers, due to possible aflatoxin contamination during manufacturing. We thus aimed to measure aflatoxin concentrations in Mongolian food samples. Samples of traditional Mongolian food ('aaruul', dried meat, and dried noodles; in total 11 samples) were collected and shipped to Germany. The food samples were analyzed for aflatoxins by extraction, immunoaffinity purification, and subsequent HPLC with fluorescence detection. The traditional Mongolian food samples did not contain any detectable amounts of aflatoxin. Since Mongolian food does not contain aflatoxins, the cause for the increasing HCC incidence in Mongolia is probably due to a high prevalence of viral hepatitides. Further studies to identify the reason for this development are warranted. © 2014 S. Karger AG, Basel.

  19. Assessment of aflatoxin exposure using serum and urinary biomarkers in São Paulo, Brazil: A pilot study.

    PubMed

    Jager, Alessandra V; Tonin, Fernando G; Baptista, Gabriela Z; Souto, Pollyana C M C; Oliveira, Carlos A F

    2016-05-01

    The aim of this study was to evaluate the human exposure of individuals from Pirassununga, Brazil, to dietary aflatoxins B1 (AFB1) and M1 (AFM1) by determination of serum AFB1-lysine and urinary aflatoxin biomarkers (AFM1 and AFB1-N(7)-guanine). The participants were recruited among employees from a Campus of the University of São Paulo, which provided food samples from their homes, as well as serum and urine samples four times every three months, from June 2011 until March 2012. The probable daily intake (PDI) of aflatoxin was estimated by using the results from analysis of food products collected by the time of samples collection, and data from a 24-hour dietary recall questionnaire. Analyses of AFB1 and AFM1 in food samples were conducted by high-performance liquid chromatography with fluorescence detection. Biomarkers in serum and urine were determined by tandem mass spectrometry. AFB1 and AFM1 were detected in 38 samples of cereals (28%, N=136) and 31 milk products (36%, N=86), respectively. AFB1-lysine and AFB1-N(7)-guanine and were not detected in serum or urine samples, respectively. However, AFM1 was found in 74 urine samples (65%), at mean levels in the 4 sampling times ranging from 0.37±0.23 to 1.70±2.88pg/mg creatinine. The mean PDI varied among different sampling times, ranging from 0.09±0.09 to 1.35±5.98ng/kg body weight/day. A modest though significant correlation (r=0.45; p=0.03; N=23) was found for the first time in Brazil between the AFM1 concentration in urine and the PDI for total aflatoxins (AFB1+AFM1) in sampling 1 (June 2011). Urinary AFM1 was confirmed as very sensitive for monitoring the human exposure to dietary aflatoxin. Further studies using serum and urinary biomarkers are needed to estimate the aflatoxin exposure of populations in higher risk areas in Brazil.

  20. Antigenotoxic Studies of Different Substances to Reduce the DNA Damage Induced by Aflatoxin B1 and Ochratoxin A

    PubMed Central

    Madrigal-Santillán, Eduardo; Morales-González, José A.; Vargas-Mendoza, Nancy; Reyes-Ramírez, Patricia; Cruz-Jaime, Sandra; Sumaya-Martínez, Teresa; Pérez-Pastén, Ricardo; Madrigal-Bujaidar, Eduardo

    2010-01-01

    Mycotoxins are produced mainly by the mycelial structure of filamentous fungi, or more specifically, molds. These secondary metabolites are synthesized during the end of the exponential growth phase and appear to have no biochemical significance in fungal growth and development. The contamination of foods and feeds with mycotoxins is a significant problem for the adverse effects on humans, animals, and crops that result in illnesses and economic losses. The toxic effect of the ingestion of mycotoxins in humans and animals depends on a number of factors including intake levels, duration of exposure, toxin species, mechanisms of action, metabolism, and defense mechanisms. In general, the consumption of contaminated food and feed with mycotoxin induces to neurotoxic, immunosuppressive, teratogenic, mutagenic, and carcinogenic effect in humans and/or animals. The most significant mycotoxins in terms of public health and agronomic perspective include the aflatoxins, ochratoxin A (OTA), trichothecenes, fumonisins, patulin, and the ergot alkaloids. Due to the detrimental effects of these mycotoxins, several strategies have been developed in order to reduce the risk of exposure. These include the degradation, destruction, inactivation or removal of mycotoxins through chemical, physical and biological methods. However, the results obtained with these methods have not been optimal, because they may change the organoleptic characteristics and nutritional values of food. Another alternative strategy to prevent or reduce the toxic effects of mycotoxins is by applying antimutagenic agents. These substances act according to several extra- or intracellular mechanisms, their main goal being to avoid the interaction of mycotoxins with DNA; as a consequence of their action, these agents would inhibit mutagenesis and carcinogenesis. This article reviews the main strategies used to control AFB1 and ochratoxin A and contains an analysis of some antigenotoxic substances that reduce the

  1. Non-aflatoxigenic Aspergillus flavus as potential biocontrol agents to reduce aflatoxin contamination in peanuts harvested in Northern Argentina.

    PubMed

    Alaniz Zanon, María Silvina; Barros, Germán Gustavo; Chulze, Sofía Noemí

    2016-08-16

    Biological control is one of the most promising strategies for preventing aflatoxin contamination in peanuts at field stage. A population of 46 native Aspergillus flavus nonaflatoxin producers were analysed based on phenotypic, physiological and genetic characteristics. Thirty-three isolates were characterized as L strain morphotype, 3 isolates as S strain morphotype, and 10 isolates did not produce sclerotia. Only 11 of 46 non-aflatoxigenic isolates did not produce cyclopiazonic acid. The vegetative compatibility group (VCG) diversity index for the population was 0.37. For field trials we selected the non-aflatoxigenic A. flavus AR27, AR100G and AFCHG2 strains. The efficacy of single and mixed inocula as potential biocontrol agents in Northern Argentina was evaluated through a 2-year study (2014-2015). During the 2014 peanut growing season, most of the treatments reduced the incidence of aflatoxigenic strains in both soil and peanut kernel samples, and no aflatoxin was detected in kernels. During the 2015 growing season, there was a reduction of aflatoxigenic strains in kernel samples from the plots treated with the potential biocontrol agents. Reductions of aflatoxin contamination between 78.36% and 89.55% were observed in treated plots in comparison with the un-inoculated control plots. This study provides the first data on aflatoxin biocontrol based on competitive exclusion in the peanut growing region of Northern Argentina, and proposes bioproducts with potential use as biocontrol agents. Copyright © 2016. Published by Elsevier B.V.

  2. The microRNAs as potential biomarkers for predicting the onset of aflatoxin exposure in human beings: a review

    PubMed Central

    Valencia-Quintana, Rafael; Sánchez-Alarcón, Juana; Tenorio-Arvide, María G.; Deng, Youjun; Montiel-González, José M. R.; Gómez-Arroyo, Sandra; Villalobos-Pietrini, Rafael; Cortés-Eslava, Josefina; Flores-Márquez, Ana R.; Arenas-Huertero, Francisco

    2014-01-01

    The identification of aflatoxins as human carcinogens has stimulated extensive research efforts, which continue to the present, to assess potential health hazards resulting from contamination of the human food supply and to minimize exposure. The use of biomarkers that are mechanistically supported by toxicological studies will be important tools for identifying stages in the progression of development of the health effects of environmental agents. miRNAs are small non-coding mRNAs that regulate post-transcriptional gene expression. Also, they are molecular markers of cellular responses to various chemical agents. Growing evidence has demonstrated that environmental chemicals can induce changes in miRNA expression. miRNAs are good biomarkers because they are well defined, chemically uniform, restricted to a manageable number of species, and stable in cells and in the circulation. miRNAs have been used as serological markers of HCC and other tumors. The expression patterns of different miRNAs can distinguish among HCC-hepatitis viruses related, HCC cirrhosis-derivate, and HCC unrelated to either of them. The main objective of this review is to find unreported miRNAs in HCC related to other causes, so that they can be used as specific molecular biomarkers in populations exposed to aflatoxins and as early markers of exposure, damage/presence of HCC. Until today specific miRNAs as markers for aflatoxins-exposure and their reliability are currently lacking. Based on their elucidated mechanisms of action, potential miRNAs that could serve as possible markers of HCC by exposure to aflatoxins are miR-27a, miR-27b, miR-122, miR-148, miR-155, miR-192, miR-214, miR-221, miR-429, and miR-500. Future validation for all of these miRNAs will be needed to assess their prognostic significance and confirm their relationship with the induction of HCC due to aflatoxin exposure. PMID:24672518

  3. The microRNAs as potential biomarkers for predicting the onset of aflatoxin exposure in human beings: a review.

    PubMed

    Valencia-Quintana, Rafael; Sánchez-Alarcón, Juana; Tenorio-Arvide, María G; Deng, Youjun; Montiel-González, José M R; Gómez-Arroyo, Sandra; Villalobos-Pietrini, Rafael; Cortés-Eslava, Josefina; Flores-Márquez, Ana R; Arenas-Huertero, Francisco

    2014-01-01

    The identification of aflatoxins as human carcinogens has stimulated extensive research efforts, which continue to the present, to assess potential health hazards resulting from contamination of the human food supply and to minimize exposure. The use of biomarkers that are mechanistically supported by toxicological studies will be important tools for identifying stages in the progression of development of the health effects of environmental agents. miRNAs are small non-coding mRNAs that regulate post-transcriptional gene expression. Also, they are molecular markers of cellular responses to various chemical agents. Growing evidence has demonstrated that environmental chemicals can induce changes in miRNA expression. miRNAs are good biomarkers because they are well defined, chemically uniform, restricted to a manageable number of species, and stable in cells and in the circulation. miRNAs have been used as serological markers of HCC and other tumors. The expression patterns of different miRNAs can distinguish among HCC-hepatitis viruses related, HCC cirrhosis-derivate, and HCC unrelated to either of them. The main objective of this review is to find unreported miRNAs in HCC related to other causes, so that they can be used as specific molecular biomarkers in populations exposed to aflatoxins and as early markers of exposure, damage/presence of HCC. Until today specific miRNAs as markers for aflatoxins-exposure and their reliability are currently lacking. Based on their elucidated mechanisms of action, potential miRNAs that could serve as possible markers of HCC by exposure to aflatoxins are miR-27a, miR-27b, miR-122, miR-148, miR-155, miR-192, miR-214, miR-221, miR-429, and miR-500. Future validation for all of these miRNAs will be needed to assess their prognostic significance and confirm their relationship with the induction of HCC due to aflatoxin exposure.

  4. Assessment of workers' exposure to aflatoxin B1 in a Portuguese waste industry.

    PubMed

    Viegas, Susana; Veiga, Luisa; Figueiredo, Paula; Almeida, Ana; Carolino, Elisabete; Viegas, Carla

    2015-03-01

    Aflatoxin B1 (AFB1) is considered by different International Agencies as a genotoxic and potent hepatocarcinogen. However, despite the fact that the fungi producing this compound are detected in some work environments, AFB1 is rarely monitored in occupational settings. The aim of the present investigation was to assess exposure to AFB1 of workers from one Portuguese waste company located in the outskirt of Lisbon. Occupational exposure assessment to AFB1 was done with a biomarker of internal dose that measures AFB1 in the serum by enzyme-linked immunosorbent assay. Forty-one workers from the waste company were enrolled in this study (26 from sorting; 9 from composting; 6 from incineration). A control group (n = 30) was also considered in order to know the AFB1 background levels for the Portuguese population. All the workers showed detectable levels of AFB1 with values ranging from 2.5ng ml(-1) to 25.9ng ml(-1) with a median value of 9.9±5.4ng ml(-1). All of the controls showed values below the method's detection limit. Results obtained showed much higher (8-fold higher) values when compared with other Portuguese settings already studied, such as poultry and swine production. Besides this mycotoxin, other mycotoxins are probably present in this occupational setting and this aspect should be taken into consideration for the risk assessment process due to possible synergistic reactions. The data obtained suggests that exposure to AFB1 occurs in a waste management setting and claims attention for the need of appliance of preventive and protective safety measures. © The Author 2014. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  5. Expression Profiling Coupled with In-silico Mapping Identifies Candidate Genes for Reducing Aflatoxin Accumulation in Maize

    PubMed Central

    Dhakal, Ramesh; Chai, Chenglin; Karan, Ratna; Windham, Gary L.; Williams, William P.; Subudhi, Prasanta K.

    2017-01-01

    Aflatoxin, produced by Aspergillus flavus, is hazardous to health of humans and livestock. The lack of information about large effect QTL for resistance to aflatoxin accumulation is a major obstacle to employ marker-assisted selection for maize improvement. The understanding of resistance mechanisms of the host plant and the associated genes is necessary for improving resistance to A. flavus infection. A suppression subtraction hybridization (SSH) cDNA library was made using the developing kernels of Mp715 (resistant inbred) and B73 (susceptible inbred) and 480 randomly selected cDNA clones were sequenced to identify differentially expressed genes (DEGs) in response to A. flavus infection and map these clones onto the corn genome by in-silico mapping. A total of 267 unigenes were identified and majority of genes were related to metabolism, stress response, and disease resistance. Based on the reverse northern hybridization experiment, 26 DEGs were selected for semi-quantitative RT-PCR analysis in seven inbreds with variable resistance to aflatoxin accumulation at two time points after A. flavus inoculation. Most of these genes were highly expressed in resistant inbreds. Quantitative RT-PCR analysis validated upregulation of PR-4, DEAD-box RNA helicase, and leucine rich repeat family protein in resistant inbreds. Fifty-six unigenes, which were placed on linkage map through in-silico mapping, overlapped the QTL regions for resistance to aflatoxin accumulation identified in a mapping population derived from the cross between B73 and Mp715. Since majority of these mapped genes were related to disease resistance, stress response, and metabolism, these should be ideal candidates to investigate host pathogen interaction and to reduce aflatoxin accumulation in maize. PMID:28428796

  6. Systems responses of rats to aflatoxin B1 exposure revealed with metabonomic changes in multiple biological matrices.

    PubMed

    Zhang, Limin; Ye, Yangfang; An, Yanpeng; Tian, Yuan; Wang, Yulan; Tang, Huiru

    2011-02-04

    Exposure to aflatoxins causes liver fibrosis and hepatocellular carcinoma posing a significant health risk for human populations and livestock. To understand the mammalian systems responses to aflatoxin-B1 (AFB1) exposure, we analyzed the AFB1-induced metabonomic changes in multiple biological matrices (plasma, urine, and liver) of rats using (1)H NMR spectroscopy together with clinical biochemistry and histopathologic assessments. We found that AFB1 exposure caused significant elevation of glucose, amino acids, and choline metabolites (choline, phosphocholine, and glycerophosphocholine) in plasma but reduction of plasma lipids. AFB1 also induced elevation of liver lipids, amino acids (tyrosine, histidine, phenylalanine, leucine, isoleucine, and valine), choline, and nucleic acid metabolites (inosine, adenosine, and uridine) together with reduction of hepatic glycogen and glucose. AFB1 further caused decreases in urinary TCA cycle intermediates (2-oxoglutarate and citrate) and elevation of gut microbiota cometabolites (phenylacetylglycine and hippurate). These indicated that AFB1 exposure caused hepatic steatosis accompanied with widespread metabolic changes including lipid and cell membrane metabolisms, protein biosynthesis, glycolysis, TCA cycle, and gut microbiota functions. This implied that AFB1 exposure probably caused oxidative-stress-mediated impairments of mitochondria functions. These findings provide an overview of biochemical consequences of AFB1 exposure and comprehensive insights into the metabolic aspects of AFB1-induced hepatotoxicity in rats.

  7. Chlorophyllin intervention reduces aflatoxin-DNA adducts in individuals at high risk for liver cancer.

    PubMed

    Egner, P A; Wang, J B; Zhu, Y R; Zhang, B C; Wu, Y; Zhang, Q N; Qian, G S; Kuang, S Y; Gange, S J; Jacobson, L P; Helzlsouer, K J; Bailey, G S; Groopman, J D; Kensler, T W

    2001-12-04

    Residents of Qidong, People's Republic of China, are at high risk for development of hepatocellular carcinoma, in part from consumption of foods contaminated with aflatoxins. Chlorophyllin, a mixture of semisynthetic, water-soluble derivatives of chlorophyll that is used as a food colorant and over-the-counter medicine, has been shown to be an effective inhibitor of aflatoxin hepatocarcinogenesis in animal models by blocking carcinogen bioavailability. In a randomized, double-blind, placebo-controlled chemoprevention trial, we tested whether chlorophyllin could alter the disposition of aflatoxin. One hundred and eighty healthy adults from Qidong were randomly assigned to ingest 100 mg of chlorophyllin or a placebo three times a day for 4 months. The primary endpoint was modulation of levels of aflatoxin-N(7)-guanine adducts in urine samples collected 3 months into the intervention measured by using sequential immunoaffinity chromatography and liquid chromatography-electrospray mass spectrometry. This aflatoxin-DNA adduct excretion product serves as a biomarker of the biologically effective dose of aflatoxin, and elevated levels are associated with increased risk of liver cancer. Adherence to the study protocol was outstanding, and no adverse events were reported. Aflatoxin-N(7)-guanine could be detected in 105 of 169 available samples. Chlorophyllin consumption at each meal led to an overall 55% reduction (P = 0.036) in median urinary levels of this aflatoxin biomarker compared with those taking placebo. Thus, prophylactic interventions with chlorophyllin or supplementation of diets with foods rich in chlorophylls may represent practical means to prevent the development of hepatocellular carcinoma or other environmentally induced cancers.

  8. Effects of a Calcium Bentonite Clay in Diets Containing Aflatoxin when Measuring Liver Residues of Aflatoxin B₁ in Starter Broiler Chicks.

    PubMed

    Fowler, Justin; Li, Wei; Bailey, Christopher

    2015-08-26

    Research has shown success using clay-based binders to adsorb aflatoxin in animal feeds; however, no adsorbent has been approved for the prevention or treatment of aflatoxicosis. In this study, growth and relative organ weights were evaluated along with a residue analysis for aflatoxin B₁ in liver tissue collected from broiler chickens consuming dietary aflatoxin (0, 600, 1200, and 1800 µg/kg) both with and without 0.2% of a calcium bentonite clay additive (TX4). After one week, only the combined measure of a broiler productivity index was significantly affected by 1800 µg/kg aflatoxin. However, once birds had consumed treatment diets for two weeks, body weights and relative kidney weights were affected by the lowest concentration. Then, during the third week, body weights, feed conversion, and the productivity index were affected by the 600 µg/kg level. Results also showed that 0.2% TX4 was effective at reducing the accumulation of aflatoxin B₁ residues in the liver and improving livability in birds fed aflatoxin. The time required to clear all residues from the liver was less than one week. With evidence that the liver's ability to process aflatoxin becomes relatively efficient within three weeks, this would imply that an alternative strategy for handling aflatoxin contamination in feed could be to allow a short, punctuated exposure to a higher level, so long as that exposure is followed by at least a week of a withdrawal period on a clean diet free of aflatoxin.

  9. Mutational spectra of aflatoxin B1 in vivo establish biomarkers of exposure for human hepatocellular carcinoma.

    PubMed

    Chawanthayatham, Supawadee; Valentine, Charles C; Fedeles, Bogdan I; Fox, Edward J; Loeb, Lawrence A; Levine, Stuart S; Slocum, Stephen L; Wogan, Gerald N; Croy, Robert G; Essigmann, John M

    2017-04-11

    Aflatoxin B1 (AFB1) and/or hepatitis B and C viruses are risk factors for human hepatocellular carcinoma (HCC). Available evidence supports the interpretation that formation of AFB1-DNA adducts in hepatocytes seeds a population of mutations, mainly G:C→T:A, and viral processes synergize to accelerate tumorigenesis, perhaps via inflammation. Responding to a need for early-onset evidence predicting disease development, highly accurate duplex sequencing was used to monitor acquisition of high-resolution mutational spectra (HRMS) during the process of hepatocarcinogenesis. Four-day-old male mice were treated with AFB1 using a regimen that induced HCC within 72 wk. For analysis, livers were separated into tumor and adjacent cellular fractions. HRMS of cells surrounding the tumors revealed predominantly G:C→T:A mutations characteristic of AFB1 exposure. Importantly, 25% of all mutations were G→T in one trinucleotide context (CGC; the underlined G is the position of the mutation), which is also a hotspot mutation in human liver tumors whose incidence correlates with AFB1 exposure. The technology proved sufficiently sensitive that the same distinctive spectrum was detected as early as 10 wk after dosing, well before evidence of neoplasia. Additionally, analysis of tumor tissue revealed a more complex pattern than observed in surrounding hepatocytes; tumor HRMS were a composite of the 10-wk spectrum and a more heterogeneous set of mutations that emerged during tumor outgrowth. We propose that the 10-wk HRMS reflects a short-term mutational response to AFB1, and, as such, is an early detection metric for AFB1-induced liver cancer in this mouse model that will be a useful tool to reconstruct the molecular etiology of human hepatocarcinogenesis.

  10. Mutational spectra of aflatoxin B1 in vivo establish biomarkers of exposure for human hepatocellular carcinoma

    PubMed Central

    Chawanthayatham, Supawadee; Valentine, Charles C.; Fedeles, Bogdan I.; Fox, Edward J.; Loeb, Lawrence A.; Levine, Stuart S.; Slocum, Stephen L.; Wogan, Gerald N.; Croy, Robert G.; Essigmann, John M.

    2017-01-01

    Aflatoxin B1 (AFB1) and/or hepatitis B and C viruses are risk factors for human hepatocellular carcinoma (HCC). Available evidence supports the interpretation that formation of AFB1-DNA adducts in hepatocytes seeds a population of mutations, mainly G:C→T:A, and viral processes synergize to accelerate tumorigenesis, perhaps via inflammation. Responding to a need for early-onset evidence predicting disease development, highly accurate duplex sequencing was used to monitor acquisition of high-resolution mutational spectra (HRMS) during the process of hepatocarcinogenesis. Four-day-old male mice were treated with AFB1 using a regimen that induced HCC within 72 wk. For analysis, livers were separated into tumor and adjacent cellular fractions. HRMS of cells surrounding the tumors revealed predominantly G:C→T:A mutations characteristic of AFB1 exposure. Importantly, 25% of all mutations were G→T in one trinucleotide context (CGC; the underlined G is the position of the mutation), which is also a hotspot mutation in human liver tumors whose incidence correlates with AFB1 exposure. The technology proved sufficiently sensitive that the same distinctive spectrum was detected as early as 10 wk after dosing, well before evidence of neoplasia. Additionally, analysis of tumor tissue revealed a more complex pattern than observed in surrounding hepatocytes; tumor HRMS were a composite of the 10-wk spectrum and a more heterogeneous set of mutations that emerged during tumor outgrowth. We propose that the 10-wk HRMS reflects a short-term mutational response to AFB1, and, as such, is an early detection metric for AFB1-induced liver cancer in this mouse model that will be a useful tool to reconstruct the molecular etiology of human hepatocarcinogenesis. PMID:28351974

  11. Population attributable risk of aflatoxin-related liver cancer: systematic review and meta-analysis.

    PubMed

    Liu, Yan; Chang, Chung-Chou H; Marsh, Gary M; Wu, Felicia

    2012-09-01

    Over 4 billion people worldwide are exposed to dietary aflatoxins, which cause liver cancer (hepatocellular carcinoma, HCC) in humans. However, the population attributable risk (PAR) of aflatoxin-related HCC remains unclear. In our systematic review and meta-analysis of epidemiological studies, summary odds ratios (ORs) of aflatoxin-related HCC with 95% confidence intervals were calculated in HBV+ and HBV- individuals, as well as the general population. We calculated the PAR of aflatoxin-related HCC for each study as well as the combined studies, accounting for HBV status. Seventeen studies with 1680 HCC cases and 3052 controls were identified from 479 articles. All eligible studies were conducted in China, Taiwan, or sub-Saharan Africa. The PAR of aflatoxin-related HCC was estimated at 17% (14-19%) overall, and higher in HBV+ (21%) than HBV- (8.8%) populations. If the one study that contributed most to heterogeneity in the analysis is excluded, the summarised OR of HCC with 95% CI is 73.0 (36.0-148.3) from the combined effects of aflatoxin and HBV, 11.3 (6.75-18.9) from HBV only and 6.37 (3.74-10.86) from aflatoxin only. The PAR of aflatoxin-related HCC increases to 23% (21-24%). The PAR has decreased over time in certain Taiwanese and Chinese populations. In high exposure areas, aflatoxin multiplicatively interacts with HBV to induce HCC; reducing aflatoxin exposure to non-detectable levels could reduce HCC cases in high-risk areas by about 23%. The decreasing PAR of aflatoxin-related HCC reflects the benefits of public health interventions to reduce aflatoxin and HBV. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Population Attributable Risk of Aflatoxin-Related Liver Cancer: Systematic Review and Meta-Analysis

    PubMed Central

    Liu, Yan; Chang, Chung-Chou H.; Marsh, Gary M.; Wu, Felicia

    2012-01-01

    Background Over 4 billion people worldwide are exposed to dietary aflatoxins, which cause liver cancer (hepatocellular carcinoma, HCC) in humans. However, the population attributable risk (PAR) of aflatoxin-related HCC remains unclear. Methods In our systematic review and meta-analysis of epidemiological studies, summary odds ratios (ORs) of aflatoxin-related HCC with 95% confidence intervals were calculated in HBV+ and HBV− individuals, as well as the general population. We calculated the PAR of aflatoxin-related HCC for each study as well as the combined studies, accounting for HBV status. Results 17 studies with 1680 HCC cases and 3052 controls were identified from 479 articles. All eligible studies were conducted in China, Taiwan, or sub-Saharan Africa. The PAR of aflatoxin-related HCC was estimated at 17% (14–19%) overall, and higher in HBV+ (21%) than HBV− (8.8%) populations. If the one study that contributed most to heterogeneity in the analysis is excluded, the summarized OR of HCC with 95% CI is 73.0 (36.0–148.3) from the combined effects of aflatoxin and HBV, 11.3 (6.75–18.9) from HBV only, and 6.37 (3.74–10.86) from aflatoxin only. The PAR of aflatoxin-related HCC increases to 23% (21–24%). The PAR has decreased over time in certain Taiwanese and Chinese populations. Conclusions In high exposure areas, aflatoxin multiplicatively interacts with HBV to induce HCC; reducing aflatoxin exposure to non-detectable levels could reduce HCC cases in high-risk areas by about 23%. The decreasing PAR of aflatoxin-related HCC reflects the benefits of public health interventions to reduce aflatoxin and HBV. PMID:22405700

  13. Longitudinal evaluation of aflatoxin exposure in two cohorts in south-western Uganda.

    PubMed

    Kang, Min-Su; Nkurunziza, Peter; Muwanika, Richard; Qian, Guoqing; Tang, Lili; Song, Xiao; Xue, Kathy; Nkwata, Allan; Ssempebwa, John; Lutalo, Tom; Asiki, Gershim; Serwadda, David; Seeley, Janet; Kaleebu, Pontiano; Nalugoda, Fred; Newton, Robert; William, Jonathan H; Wang, Jia-Sheng

    2015-01-01

    Aflatoxins (AF) are a group of mycotoxins. AF exposure causes acute and chronic adverse health effects such as aflatoxicosis and hepatocellular carcinoma in human populations, especially in the developing world. In this study, AF exposure was evaluated using archived serum samples from human immunodeficiency virus (HIV)-seronegative participants from two cohort studies in south-western Uganda. AFB1-lysine (AFB-Lys) adduct levels were determined via HPLC fluorescence in a total of 713 serum samples from the General Population Cohort (GPC), covering eight time periods between 1989 and 2010. Overall, 90% (642/713) of the samples were positive for AFB-Lys and the median level was 1.58 pg mg(-1) albumin (range = 0.40-168 pg mg(-1) albumin). AFB-Lys adduct levels were also measured in a total of 374 serum samples from the Rakai Community Cohort Study (RCCS), across four time periods between 1999 and 2003. The averaged detection rate was 92.5% (346/374) and the median level was 1.18 pg mg(-1) albumin (range = 0.40-122.5 pg mg(-1) albumin). In the GPC study there were no statistically significant differences between demographic parameters, such as age, sex and level of education, and levels of serum AFB-Lys adduct. In the RCCS study, longitudinal analysis using generalised estimating equations revealed significant differences between the adduct levels and residential areas (p = 0.05) and occupations (p = 0.02). This study indicates that AF exposure in people in two populations in south-western Uganda is persistent and has not significantly changed over time. Data from one study, but not the other, indicated that agriculture workers and rural area residents had more AF exposure than those non-agricultural workers and non-rural area residents. These results suggest the need for further study of AF-induced human adverse health effects, especially the predominant diseases in the region.

  14. Molecular dosimetry of aflatoxin exposure: contribution to understanding the multifactorial etiopathogenesis of primary hepatocellular carcinoma with particular reference to hepatitis B virus.

    PubMed Central

    Wild, C P; Jansen, L A; Cova, L; Montesano, R

    1993-01-01

    Aflatoxin exposure and hepatitis B virus infection have been implicated as major risk factors for primary hepatocellular carcinoma (PHC) in high-incidence regions of the world. Investigations using the assay of aflatoxin bound to peripheral blood albumin have shown that exposure can occur throughout the life span of the individual, including during the perinatal period, in high-incidence areas such as The Gambia, Senegal, Kenya, and The People's Republic of China. The possibility of measuring aflatoxin exposure at the individual level permits an investigation of the putative mechanisms of interaction of this carcinogen with HBV in the etiopathogenesis of PHC. Animal models, e.g., Pekin duck and HBV-transgenic mice, have also been used to study these questions, and the available data are reviewed. PMID:8391433

  15. Effects of maternal exposure to aflatoxin B1 during pregnancy on fertility output of dams and developmental, behavioral and reproductive consequences in female offspring using a rat model.

    PubMed

    Supriya, Ch; Akhila, B; Pratap Reddy, K; Girish, B P; Sreenivasula Reddy, P

    2016-01-01

    A suboptimal in utero environment can have detrimental effects on the pregnancy and long-term adverse "programing" effects on the offspring. Aflatoxin B1 is one of the potent reproductive toxicants and currently detected in both milk and tissues. This article focuses on the effects of prenatal exposure to graded doses of aflatoxin B1 on the pregnancy outcomes of dams and postnatal developments of the female offspring, since these issues have ethological relevance in both animals and humans. Pregnant Wistar rats were injected intramuscularly with vehicle or aflatoxin B1 (10, 20, 50 or 100 μg/kg body weight/day) on days 12-19 of gestation. At parturition, newborns were observed for clinical signs of toxicity and survival. The female offspring were examined through a battery of tests in order to evaluate their developmental, behavioral and reproductive end points. All animals were born alive. The litter size of the aflatoxin B1 treated rats was comparable to the controls. However, the birth weight of the pups in the experimental group was significantly lower when compared to controls. Significant and persistent lags in cliff avoidance, negative geotaxis, surface rightening activity and ascending wire mesh, with a delay in elapsed time for vaginal opening were detected in the female progeny exposed to aflatoxin B1 during embryonic development. The locomotor activity and exploratory behavior in experimental females were significantly decreased than that of controls. Embryonic exposure to aflatoxin B1 also resulted in prolonged stress response, irregular estrus and suppressed fertility output in the progeny at their adulthood. These results indicate that in utero exposure to aflatoxin B1 severely compromised postnatal development of neonatal rats and caused irregular estrus that was accompanied by suppressed fertility output.

  16. A Prospective Study of Growth and Biomarkers of Exposure to Aflatoxin and Fumonisin during Early Childhood in Tanzania

    PubMed Central

    Shirima, Candida P.; Kimanya, Martin E.; Routledge, Michael N.; Srey, Chou; Kinabo, Joyce L.; Humpf, Hans-Ulrich; Wild, Christopher P.; Tu, Yu-Kang

    2014-01-01

    Background: Aflatoxin and fumonisin are toxic food contaminants. Knowledge about effects of their exposure and coexposure on child growth is inadequate. Objective: We investigated the association between child growth and aflatoxin and fumonisin exposure in Tanzania. Methods: A total of 166 children were recruited at 6–14 months of age and studied at recruitment, and at the 6th and 12th month following recruitment. Blood and urine samples were collected and analyzed for plasma aflatoxin–albumin adducts (AF-alb) using ELISA, and urinary fumonisin B1 (UFB1) using liquid chromatography–mass spectrometry, respectively. Anthropometric measurements were taken, and growth index z-scores were computed. Results: AF-alb geometric mean concentrations (95% CIs) were 4.7 (3.9, 5.6), 12.9 (9.9, 16.7), and 23.5 (19.9, 27.7) pg/mg albumin at recruitment, 6 months, and 12 months from recruitment, respectively. At these respective sampling times, geometric mean UFB1 concentrations (95% CI) were 313.9 (257.4, 382.9), 167.3 (135.4, 206.7), and 569.5 (464.5, 698.2) pg/mL urine, and the prevalence of stunted children was 44%, 55%, and 56%, respectively. UFB1 concentrations at recruitment were negatively associated with length-for-age z-scores (LAZ) at 6 months (p = 0.016) and at 12 months from recruitment (p = 0.014). The mean UFB1 of the three sampling times (at recruitment and at 6 and 12 months from recruitment) in each child was negatively associated with LAZ (p < 0.001) and length velocity (p = 0.004) at 12 months from recruitment. The negative association between AF-alb and child growth did not reach statistical significance. Conclusions: Exposure to fumonisin alone or coexposure with aflatoxins may contribute to child growth impairment. Citation: Shirima CP, Kimanya ME, Routledge MN, Srey C, Kinabo JL, Humpf HU, Wild CP, Tu YK, Gong YY. 2015. A prospective study of growth and biomarkers of exposure to aflatoxin and fumonisin during early childhood in Tanzania. Environ Health

  17. Aflatoxin and hepatitis B virus biomarkers: a paradigm for complex environmental exposures and cancer risk.

    PubMed

    Groopman, John D; Johnson, Denise; Kensler, Thomas W

    2005-01-01

    The use of biomarkers in molecular epidemiology studies for identifying stages in the progression of development of the health effects of environmental agents has the potential for providing important information for critical regulatory, clinical and public health problems. Investigations of aflatoxins probably represents one of the most extensive data sets in the field and this work may serve as a template for future studies of other environmental agents. The aflatoxins are naturally occurring mycotoxins found on foods such as corn, peanuts, various other nuts and cottonseed and they have been demonstrated to be carcinogenic in many experimental models. As a result of nearly thirty years of study, experimental data and epidemiological studies in human populations, aflatoxin B(1) was classified as carcinogenic to humans by the International Agency for Research on Cancer. The long-term goal of the research described herein is the application of biomarkers to the development of preventative interventions for use in human populations at high-risk for cancer. Several of the aflatoxin specific biomarkers have been validated in epidemiological studies and are now being used as intermediate biomarkers in prevention studies. The development of these aflatoxin biomarkers has been based upon the knowledge of the biochemistry and toxicology of aflatoxins gleaned from both experimental and human studies. These biomarkers have subsequently been utilised in experimental models to provide data on the modulation of these markers under different situations of disease risk. This systematic approach provides encouragement for preventive interventions and should serve as a template for the development, validation and application of other chemical-specific biomarkers to cancer or other chronic diseases. This systematic approach provides encouragement for preventive interventions and should serve as a template for the development, validation and application of other chemical

  18. Identification of atoxigenic Aspergillus flavus isolates to reduce aflatoxin contamination of maize in Kenya

    USDA-ARS?s Scientific Manuscript database

    Acute aflatoxin poisonings (aflatoxicosis) in Kenya have led to the deaths of several hundred people between 2004 and 2006. Etiology of contamination in the outbreak districts (Eastern Province) identified an unusual fungal community structure dominated by the highly toxigenic Aspergillus flavus S s...

  19. Efficacy of probiotic bacteria in reducing Aspergillus parasiticus aflatoxin production and hepatic cytotoxicity in vitro

    USDA-ARS?s Scientific Manuscript database

    Aspergillus parasiticus produces highly hepatocarcinogenic aflatoxins (AF) in grains, which are used as poultry feed ingredients. Contamination of poultry feed with AF is a major concern to the poultry industry due to serious economic losses stemming from poor performance and diminished egg hatchabi...

  20. Association of Aflatoxin and Gallbladder Cancer.

    PubMed

    Koshiol, Jill; Gao, Yu-Tang; Dean, Michael; Egner, Patricia; Nepal, Chirag; Jones, Kristine; Wang, Bingsheng; Rashid, Asif; Luo, Wen; Van Dyke, Alison L; Ferreccio, Catterina; Malasky, Michael; Shen, Ming-Chang; Zhu, Bin; Andersen, Jesper B; Hildesheim, Allan; Hsing, Ann W; Groopman, John

    2017-08-01

    even higher proportion in high-risk areas. If our findings are verified, reducing aflatoxin exposure might reduce the incidence of gallbladder cancer. Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.

  1. Assessment of exposure of Egyptian infants to aflatoxin M1 through breast milk.

    PubMed

    Tomerak, Rania H; Shaban, Hala H; Khalafallah, Osama A; El Shazly, Maha N

    2011-01-01

    Mothers are exposed to many toxins that can reach their infants through breast milk. One of these toxins is aflatoxins, produced by Aspergillus fungus. Aspergillus colonizes grains, especially in tropical regions where there is high temperature and humidity. Aflatoxins are highly toxic, mutagenic, teratogenic, and carcinogenic. One of these is aflatoxin B1 that is excreted in breast milk as aflatoxin M1 (AFM1). This is a cross-sectional study in which 150 mother-infant dyads were included. All the infants were exclusively breastfed. Infant weights' standard deviation scores were documented at birth and at 6 months. At 6 months, before starting weaning, AFM1 was measured in breast milk by enzyme-linked immunosorbent assay and by liver enzymes; alanine aminotransferase (ALT) and aspartate aminotransferase (AST) for all mothers and infants. Ninety-eight mothers (65.3%) had AFM1-positive breast milk samples (AFM1>0.05 μg/l according to the European Community and Codex Alimentarius). AFM1 levels ranged between 0.2 and 19.0 μg/l (mean: 7.1±5.0 μg/l). In cases considered negative, AFM1 levels ranged between 0.01and 0.05 μg/l (mean: 0.04±0.01 μg/l). Infants of AFM1-positive mothers had lower weight standard deviation scores at birth and at 6 months (P=0.04 and 0.0001). ALT and aspartate aminotransferase of mothers and ALT of infants were significantly higher in dyads having AFM1-positive breast milk (P=0.0001, 0.0001, and 0.03, respectively). Aflatoxins represent a real threat in Egypt. The higher liver enzymes in AFM1-positive cases might represent an alarm toward future development of hepatocellular carcinoma. Cooperation of ministries is recommended to combat this problem. The public should be educated about proper food storage and about the hazards of aflatoxin ingestion.

  2. Human health implications from co-exposure to aflatoxins and fumonisins in maize-based foods in Latin America: Guatemala as a case study

    USDA-ARS?s Scientific Manuscript database

    Co-occurence of fumonisin B1 (FB1) and aflatoxin B1 (AFB1) in maize has been demonstrated in many surveys. Combined-exposure to FB1 and AFB1 was of concern to the Joint FAO/WHO Expert Committee on Food Additives because of the known genotoxicity of AFB1 and the ability of FB1 to induce regenerative...

  3. Sampling hazelnuts for aflatoxin: Effects of sample size and accetp/reject limit on reducing risk of misclassifying lots

    USDA-ARS?s Scientific Manuscript database

    About 100 countries have established regulatory limits for aflatoxin in food and feeds. Because these limits vary widely among regulating countries, the Codex Committee on Food Additives and Contaminants (CCFAC) began work in 2004 to harmonize aflatoxin limits and sampling plans for aflatoxin in alm...

  4. Determination of Environmental Exposure to Microcystin and Aflatoxin as a Risk for Renal Function Based on 5493 Rural People in Southwest China.

    PubMed

    Lin, Hui; Liu, Wenyi; Zeng, Hui; Pu, Chaowen; Zhang, Renping; Qiu, Zhiqun; Chen, Ji-An; Wang, Lingqiao; Tan, Yao; Zheng, Chuanfen; Yang, Xiaohong; Tian, Yingqiao; Huang, Yujing; Luo, Jiaohua; Luo, Yang; Feng, Xiaobin; Xiao, Guosheng; Feng, Lei; Li, Heng; Wang, Feng; Yuan, Changyou; Wang, Jia; Zhou, Ziyuan; Wei, Tiantian; Zuo, Yonglin; Wu, Liping; He, Lixiong; Guo, Yaoping; Shu, Weiqun

    2016-05-17

    Although the nephrotoxicity of microcystin and aflatoxin has been observed in animal and clinical cases, few population data are available. We conducted a cross-sectional study in Southwest China to investigate the association of renal function indicators (RFIs, including BUN, SCr, and eGFR) with exposure to microcystin and aflatoxin in 5493 members of the general population. Microcystin-LR levels in water and aquatic products and aflatoxin B1 levels in daily foods were measured by ELISA, and individual estimated daily intake (EDI) was assessed on the basis of the measurement and questionnaire. We found that participants with abnormal RFIs had a much higher mean level of microcystin-LR EDI than those with normal RFIs and that there was a significant increasing trend for abnormal rates and odds ratios of RFIs with increasing microcystin-LR EDI quartiles (p for trend = 0.000). Compared with the lowest quartile of microcystin-LR exposure, those in the highest quartile had significantly higher risks of abnormal BUN (OR = 1.80, 95% CI = 1.34-2.42), SCr (OR = 4.58, 95% CI = 2.92-7.21), and eGFR (OR = 4.41, 95% CI = 2.55-7.63), respectively, but no higher risk was found in subjects with higher AFB1 exposure. After adjustment for confounding factors, risk associations with microcystin-LR persisted. Consequently, our results suggest that microcystin, rather than aflatoxin, might be one important risk of renal-function impairment.

  5. Exposure Assessment of Infants to Aflatoxin M1 through Consumption of Breast Milk and Infant Powdered Milk in Brazil

    PubMed Central

    Ishikawa, Angélica T.; Takabayashi-Yamashita, Cássia R.; Ono, Elisabete Y. S.; Bagatin, Artur K.; Rigobello, Fabiana F.; Kawamura, Osamu; Hirooka, Elisa Y.; Itano, Eiko N.

    2016-01-01

    Aflatoxin M1 (AFM1) is an important biomarker that can be used to evaluate aflatoxin exposure in both humans and animals. The aim of this study was to evaluate the exposure degree of infants to AFM1 through consumption of breast milk and infant powdered milk in Brazil. For this purpose, the estimated daily intake (EDI) for infants was calculated based on the AFM1 levels analyzed in 94 breast milk (BM) samples collected in Southern Brazil, and 16 infant powdered milk (IPM) samples commonly commercialized in Brazil. AFM1 was detected in 5.3% (n = 5) and 43.8% (n = 7) of BM and IPM samples, with mean levels of 0.003 ng/g and 0.011 ng/g, respectively. All the IPM samples showed AFM1 levels lower than those established by the Brazilian guidelines (5 ng/g), and in most of the samples (81.25%) levels were below the maximum limit tolerated by the European Commission (0.025 ng/g). The EDI of AFM1 for infants aged zero to 12 months old showed values from 0.018 to 0.069 ng/kg body weight/day for BM, and 0.078 to 0.306 ng/kg body weight/day for IPM. Hazard index (HI) values for BM and IPM were less than one, except for IPM intended for infants up to one month. In conclusion, the exposure of infants to AFM1 was low, but continuous monitoring of mycotoxin levels is essential to minimize infant health risk. PMID:27589799

  6. Exposure Assessment of Infants to Aflatoxin M₁ through Consumption of Breast Milk and Infant Powdered Milk in Brazil.

    PubMed

    Ishikawa, Angélica T; Takabayashi-Yamashita, Cássia R; Ono, Elisabete Y S; Bagatin, Artur K; Rigobello, Fabiana F; Kawamura, Osamu; Hirooka, Elisa Y; Itano, Eiko N

    2016-08-31

    Aflatoxin M₁ (AFM₁) is an important biomarker that can be used to evaluate aflatoxin exposure in both humans and animals. The aim of this study was to evaluate the exposure degree of infants to AFM₁ through consumption of breast milk and infant powdered milk in Brazil. For this purpose, the estimated daily intake (EDI) for infants was calculated based on the AFM₁ levels analyzed in 94 breast milk (BM) samples collected in Southern Brazil, and 16 infant powdered milk (IPM) samples commonly commercialized in Brazil. AFM₁ was detected in 5.3% (n = 5) and 43.8% (n = 7) of BM and IPM samples, with mean levels of 0.003 ng/g and 0.011 ng/g, respectively. All the IPM samples showed AFM₁ levels lower than those established by the Brazilian guidelines (5 ng/g), and in most of the samples (81.25%) levels were below the maximum limit tolerated by the European Commission (0.025 ng/g). The EDI of AFM₁ for infants aged zero to 12 months old showed values from 0.018 to 0.069 ng/kg body weight/day for BM, and 0.078 to 0.306 ng/kg body weight/day for IPM. Hazard index (HI) values for BM and IPM were less than one, except for IPM intended for infants up to one month. In conclusion, the exposure of infants to AFM₁ was low, but continuous monitoring of mycotoxin levels is essential to minimize infant health risk.

  7. Study of an Educational Hand Sorting Intervention for Reducing Aflatoxin B1 in Groundnuts in Rural Gambia.

    PubMed

    Xu, Y A; Doel, Andrew; Watson, Sinead; Routledge, Michael N; Elliott, Christopher T; Moore, Sophie E; Gong, Yun Yun

    2017-01-01

    Aflatoxin, a human liver carcinogen, frequently contaminates groundnuts, maize, rice, and other grains, especially in Africa. The aim of this study was to evaluate the effectiveness of an educational intervention that involved training rural Gambian women on how to identify and remove moldy groundnuts to reduce aflatoxin B1 (AFB1) contamination. In total, 25 women, recruited from the West Kiang region of The Gambia, were trained on how to recognize and remove moldy groundnuts. Market-purchased groundnuts were hand sorted by the women. Groundnuts were sampled at baseline (n =5), after hand sorting ("clean," n =25 and "moldy," n =25), and after roasting (n =5). All samples were analyzed for AFB1 by enzyme-linked immunosorbent assay. A reduction of 42.9% was achieved based on the median AFB1 levels at baseline and after hand sorting (clean groundnuts), whereas an alternative estimate, based on the total AFB1 in moldy and clean groundnuts, indicated a reduction of 96.7%, with a loss of only 2% of the groundnuts. By roasting the already clean sorted groundnuts, the AFB1 reduction achieved (based on median levels) was 39.3%. This educational intervention on how to identify and remove moldy groundnuts was simple and effective in reducing AFB1 contamination.

  8. Present and future directions of translational research on aflatoxin and hepatocellular carcinoma. A review.

    PubMed

    Wogan, Gerald N; Kensler, Thomas W; Groopman, John D

    2012-01-01

    animals indicating the carcinogenicity of naturally occurring mixtures of aflatoxins, aflatoxin B(1), G(1) and M(1). Aflatoxin biomarkers have also been used to show that primary prevention to reduce aflatoxin exposure can be achieved by low-technology approaches at the subsistence farm level in sub-Saharan Africa. Also, in residents of Qidong, China, oral dosing with chlorophyllin, a chlorophyll derivative, prior to each meal led to significant reduction in aflatoxin-DNA biomarker excretion, supporting the feasibility of preventive measures to reduce HCC risk in populations experiencing unavoidable aflatoxin exposure. The systematic, comprehensive approach used to create the total aflatoxin database justifies optimism for potential success of preventive interventions to ameliorate cancer risk attributable to aflatoxin exposure. This strategy could serve as a template for the development, validation and application of molecular and biochemical markers for other carcinogens and cancers as well as other chronic diseases resulting from environmental exposures.

  9. Reducing lead exposure in children

    SciTech Connect

    Farfel, M.R.

    1985-01-01

    The near elimination of lead-related childhood fatalities and encephalopathy by the 1970s and the sharp decline in mean blood lead levels nationwide documented between 1976 and 1980 are two milestones in the fight against lead poisoning. In the case of the latter, we know the antecedents, such as controls on the sale, use, and lead content of lead paint, improved chelation therapy, and increased awareness and case finding; however, the antecedents' relative contributions are not known due to a lack of evaluation. Similarly, the effect of a variety of social-welfare programs has not been evaluated. Since the 1970s, our perception of the problem of lead toxicity and consequently its control has changed. First steps have been made toward attaining one primary preventive objective, controlling the multiple sources of new inputs of lead to the biosphere that contribute to asymptomatic lead toxicity. The lead content of widely used commodities has been reduced (canned foods and gasoline) or virtually eliminated (paint). The benefits of passive measures used to attain reductions in lead exposure have been documented to a greater extent than those of active programs. The best example of a successful primary and passive preventive measure is the availability of lead-free gasoline since 1974, which largely accounts for decreases in ambient air lead concentrations nationwide and the recent shift to lower values in the distribution curve of children's blood lead levels. The latter provides a margin of safety for children before known toxic levels are reached. The contribution of reductions in dietary lead to changes in blood lead levels has not been well documented. Studies also show the benefits of the use of lead-free paint in new housing. Compared to children living in older homes with deteriorating lead paint, those living in lead-free homes are at low risk for lead toxicity.

  10. Model Averaging for Predicting the Exposure to Aflatoxin B1 Using DNA Methylation in White Blood Cells of Infants

    NASA Astrophysics Data System (ADS)

    Rahardiantoro, S.; Sartono, B.; Kurnia, A.

    2017-03-01

    In recent years, DNA methylation has been the special issue to reveal the pattern of a lot of human diseases. Huge amount of data would be the inescapable phenomenon in this case. In addition, some researchers interesting to take some predictions based on these huge data, especially using regression analysis. The classical approach would be failed to take the task. Model averaging by Ando and Li [1] could be an alternative approach to face this problem. This research applied the model averaging to get the best prediction in high dimension of data. In the practice, the case study by Vargas et al [3], data of exposure to aflatoxin B1 (AFB1) and DNA methylation in white blood cells of infants in The Gambia, take the implementation of model averaging. The best ensemble model selected based on the minimum of MAPE, MAE, and MSE of predictions. The result is ensemble model by model averaging with number of predictors in model candidate is 15.

  11. Co-occurrence of aflatoxins and ochratoxin A in dried fruits in Iran: Dietary exposure risk assessment.

    PubMed

    Heshmati, Ali; Zohrevand, Tahereh; Khaneghah, Amin Mousavi; Mozaffari Nejad, Amir Sasan; Sant'Ana, Anderson S

    2017-08-01

    In this study, the contamination levels of aflatoxins (AFs) and ochratoxin A (OTA) in 88 collected samples from Iran's market including dried mulberry, date, fig, and apricot were evaluated. The margin of exposure (MOE) was estimated to assess the risk of dietary intake of aflatoxin B1 (AFB1) and OTA. The incidence of AFB1 in dried mulberry, date, fig and apricot samples was 45.5, 40.9, 59.1, and 81.8%, respectively. Although the mean total AFs content in contaminated samples of date (2.61 μg/kg), fig (3.43 μg/kg) and apricot (2.91 μg/kg) was lower than the maximum limit set in the European Union (EU) (4 μg/kg), dried mulberry samples showed a higher contamination level (4.12 μg/kg). The co-occurrence of OTA and AFs were noted in 4 (18.9%), 2 (9.1%), 4 (18.2%), and 10 (45.5%) in the dried mulberry, date, fig and apricot samples, respectively. Based on the calculated MOE, the dietary exposure to AFs through the consumption of dried fruit in Iran poses a potential risk to consumer health. OTA was detected in 45.45%, 22.72%, 45.45%, and 50% of mulberry, date, fig and apricot samples, respectively. However, OTA levels in all types of dried fruit were below recommended level in EU regulation (10 μg/kg) and MOE >10000, representing no toxicological concerns for consumers. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. A probabilistic modeling approach to assess human inhalation exposure risks to airborne aflatoxin B 1 (AFB 1)

    NASA Astrophysics Data System (ADS)

    Liao, Chung-Min; Chen, Szu-Chieh

    To assess how the human lung exposure to airborne aflatoxin B 1 (AFB 1) during on-farm activities including swine feeding, storage bin cleaning, corn harvest, and grain elevator loading/unloading, we present a probabilistic risk model, appraised with empirical data. The model integrates probabilistic exposure profiles from a compartmental lung model with the reconstructed dose-response relationships based on an empirical three-parameter Hill equation model, describing AFB 1 cytotoxicity for inhibition response in human bronchial epithelial cells, to quantitatively estimate the inhalation exposure risks. The risk assessment results implicate that exposure to airborne AFB 1 may pose no significance to corn harvest and grain elevator loading/unloading activities, yet a relatively high risk for swine feeding and storage bin cleaning. Applying a joint probability function method based on exceedence profiles, we estimate that a potential high risk for the bronchial region (inhibition=56.69% with 95% confidence interval (CI): 35.05-72.87%) and bronchiolar region (inhibition=44.93% with 95% CI: 21.61 - 66.78%) is alarming during swine feeding activity. We parameterized the proposed predictive model that should encourage a risk-management framework for discussion of carcinogenic risk in occupational settings where inhalation of AFB 1-contaminated dust occurs.

  13. Transformation of adsorbed aflatoxin B1 on smectite at elevated temperatures

    USDA-ARS?s Scientific Manuscript database

    Aflatoxins cause liver damage and suppress immunity. Smectites can be used to reduce the bioavailability of aflatoxins through adsorption. To further reduce the toxicity of aflatoxins and to eliminate the treatments of aflatoxin-loaded smectites, degrading the adsorbed aflatoxin to nontoxic or less ...

  14. Aflatoxin and PAH exposure biomarkers in a U.S. population with a high incidence of hepatocellular carcinoma.

    PubMed

    Johnson, Natalie M; Qian, Guoqing; Xu, Li; Tietze, Danielle; Marroquin-Cardona, Alicia; Robinson, Abraham; Rodriguez, Melanie; Kaufman, Linda; Cunningham, Kyle; Wittmer, James; Guerra, Fernando; Donnelly, Kirby C; Williams, Jonathan H; Wang, Jia-Sheng; Phillips, Timothy D

    2010-11-01

    The incidence of hepatocellular carcinoma (HCC) is significantly elevated in a Hispanic community in Bexar County, Texas. Chronic exposure to dietary aflatoxins (AFs) is a major risk factor for HCC; increased risk has been linked to polycyclic aromatic hydrocarbon (PAH) co-exposure and hepatitis virus infection. The aims of this study were to assess AF and PAH exposures, investigate dietary factors that may contribute to increased AF exposure, and determine the prevalence of hepatitis virus infection in Bexar Co. Blood and urine samples were collected from 184 volunteers for biomarker analyses and hepatitis screening. Serum AFB(1)-lysine adduct, urinary AFM(1) and 1-hydroxypyrene (1-OHP) levels were measured using high-performance liquid chromatography. The average AFB(1)-lysine adduct level detected in 20.6% of serums was 3.84 ± 3.11 pg/mg albumin (range 1.01-16.57 pg/mg). AFM(1) was detected in 11.7% of urines, averaging 223.85 ± 250.56 pg/mg creatinine (range 1.89-935.49 pg/mg). AFM(1) detection was associated with increased consumption of corn tortillas (p=0.009), nuts (p=0.033) and rice (p=0.037). A significant difference was observed between mean 1-OHP values of non-smokers (0.07 ± 0.13) and smokers (0.80 ± 0.68) μmol/mol creatinine (p<0.01). A high hepatitis C virus positivity rate (7.1%) was observed. Findings suggest that the incidence and level of AF and PAH exposure were less than those observed in a high-risk population; however, participants consuming higher amounts of foods prone to AF contamination may be more vulnerable to exposure and interactions with other environmental/biological factors (i.e., HCV). Copyright © 2010 Elsevier B.V. All rights reserved.

  15. Aflatoxin and PAH exposure biomarkers in a U.S. population with a high incidence of hepatocellular carcinoma

    PubMed Central

    Johnson, Natalie M.; Qian, Guoqing; Xu, Li; Tietze, Danielle; Marroquin-Cardona, Alicia; Robinson, Abraham; Rodriguez, Melanie; Kaufman, Linda; Cunningham, Kyle; Wittmer, James; Guerra, Fernando; Donnelly, Kirby C.; Williams, Jonathan H.; Wang, Jia-Sheng; Phillips, Timothy D.

    2010-01-01

    The incidence of hepatocellular carcinoma (HCC) is significantly elevated in a Hispanic community in Bexar County, Texas. Chronic exposure to dietary aflatoxins (AFs) is a major risk factor for HCC; increased risk has been linked to polycyclic aromatic hydrocarbon (PAH) co-exposure and hepatitis virus infection. The aims of this study were to assess AF and PAH exposures, investigate dietary factors that may contribute to increased AF exposure, and determine the prevalence of hepatitis virus infection in Bexar Co. Blood and urine samples were collected from 184 volunteers for biomarker analyses and hepatitis screening. Serum AFB1-lysine adduct, urinary AFM1 and 1-hydroxypyrene (1-OHP) levels were measured using high-performance liquid chromatography. The average AFB1-lysine adduct level detected in 20.6% of serums was 3.84 ± 3.11 pg/mg albumin (range 1.01-16.57 pg/mg). AFM1 was detected in 11.7% of urines, averaging 223.85 ± 250.56 pg/mg creatinine (range 1.89-935.49 pg/mg). AFM1 detection was associated with increased consumption of corn tortillas (p = 0.009), nuts (p = 0.033) and rice (p = 0.037). A significant difference was observed between mean 1-OHP values of non-smokers (0.07 ± 0.13) and smokers (0.80 ± 0.68) μmol/mol creatinine (p < 0.01). A high hepatitis C virus positivity rate (7.1%) was observed. Findings suggest that the incidence and level of AF and PAH exposure was less than that observed in a high-risk population; however, participants consuming higher amounts of foods prone to AF contamination may be more vulnerable to exposure and interactions with other environmental/biological factors (i.e., HCV). PMID:20870273

  16. New approaches to reduce radiation exposure

    PubMed Central

    Hill, Kevin D.; Einstein, Andrew J.

    2015-01-01

    Exposure to ionizing radiation is associated with a long term risk of health effects including cancer. Radiation exposure to the U.S. population from cardiac imaging has increased markedly over the past three decades. Initiatives to reduce radiation exposure have focused on the tenets of appropriate study “justification” and “optimization” of imaging protocols. This article reviews ways to optimally reduce radiation dose across the spectrum of cardiac imaging. PMID:25962784

  17. Present and future directions of translational research on aflatoxin and hepatocellular carcinoma. A review

    PubMed Central

    Wogan, Gerald N.; Kensler, Thomas W.; Groopman, John D.

    2015-01-01

    indicating the carcinogenicity of naturally occurring mixtures of aflatoxins, aflatoxin B1, G1 and M1. Aflatoxin biomarkers have also been used to show that primary prevention to reduce aflatoxin exposure can be achieved by low-technology approaches at the subsistence farm level in sub-Saharan Africa. Also, in residents of Qidong, China, oral dosing with chlorophyllin, a chlorophyll derivative, prior to each meal led to significant reduction in aflatoxin–DNA biomarker excretion, supporting the feasibility of preventive measures to reduce HCC risk in populations experiencing unavoidable aflatoxin exposure. The systematic, comprehensive approach used to create the total aflatoxin database justifies optimism for potential success of preventive interventions to ameliorate cancer risk attributable to aflatoxin exposure. This strategy could serve as a template for the development, validation and application of molecular and biochemical markers for other carcinogens and cancers as well as other chronic diseases resulting from environmental exposures. PMID:21623489

  18. Of sick turkeys, kwashiorkor, malaria, perinatal mortality, heroin addicts and food poisoning: research on the influence of aflatoxins on child health in the tropics.

    PubMed

    Hendrickse, R G

    1997-10-01

    Similarities between the geographical and climatic prevalences of kwashiorkor and of exposure to dietary aflatoxins, and between the biochemical, metabolic and immunological derangements in kwashiorkor and those in animals exposed to aflatoxins, prompted investigation of the associations between kwashiorkor and aflatoxins. Studies in Africa in the 1980s indicated a role for these toxins in the pathogenesis of the disease. Paediatric cases of kwashiorkor are less prone to severe Plasmodium falciparum malaria than normal children. In mice infected with P. berghei, aflatoxin exposure inhibits parasite growth and ameliorates morbidity. Aflatoxins occur in < or = 40% of samples of breast milk from tropical Africa, usually as low concentrations of the relatively non-toxic derivatives of aflatoxin B1 (AFB1) but sometimes as high concentrations of the very toxic AFB1. This could explain kwashiorkor in breast-fed babies. Aflatoxin exposure occurs in > or = 30% of pregnancies in tropical Africa and the toxins are often in cord blood, sometimes at extremely high concentrations. Aflatoxins are now incriminated in neonatal jaundice and there is circumstantial evidence that they cause perinatal death and reduced birthweight. Aflatoxin-induced immunosuppresion may explain the aggressive behaviour of HIV infection in Africa. There are similarities between observations on HIV cases in Africa and those on heroin addicts in Europe, where 'street' heroin is frequently contaminated with aflatoxin. Aflatoxins were found in 20% of random urine samples from heroin addicts in the U.K. and the Netherlands. Aflatoxins have also been incriminated in episodes of food poisoning which have been associated with serious morbidity and mortality, particularly among young children.

  19. Zearalenone, deoxynivalenol and aflatoxin B1 and their metabolites in pig urine as biomarkers for mycotoxin exposure.

    PubMed

    Thieu, N Q; Pettersson, H

    2009-06-01

    Methods to determine zearalenone (ZEA), deoxynivalenol (DON), aflatoxins (AF) and their metabolites in pig urine were developed as biomarkers for pig exposure to the mycotoxins in feed. Urine samples were incubated with β-glucuronidase to cleave conjugates, extracted and cleaned-up with solid phase and immunoaffinity columns, followed by HPLC with UV and fluorescence detection. Good recoveries (83-130%), low variation (2-10%), and low detection limits (0.3-9.9 ng/ml) were obtained. The results of controlled AFB1 feeding trials found no difference in urine concentrations of AFB1 or AFM1 from pigs fed three different levels (127, 227, 327 µg/kg) of AFB1 in diets. The excretion of AFB1 and AFM1 in urine was on average 30% of the oral dose and the ratio AFB1 to AFM1 was around 23%. The analysis of 15 Vietnamese pig urine samples indicate a relatively high exposure of ZEA, DON and AF, which were found as toxin or metabolites in 47, 73, and 80% of the urine samples, respectively.

  20. Effects of a Calcium Bentonite Clay in Diets Containing Aflatoxin when Measuring Liver Residues of Aflatoxin B1 in Starter Broiler Chicks

    PubMed Central

    Fowler, Justin; Li, Wei; Bailey, Christopher

    2015-01-01

    Research has shown success using clay-based binders to adsorb aflatoxin in animal feeds; however, no adsorbent has been approved for the prevention or treatment of aflatoxicosis. In this study, growth and relative organ weights were evaluated along with a residue analysis for aflatoxin B1 in liver tissue collected from broiler chickens consuming dietary aflatoxin (0, 600, 1200, and 1800 µg/kg) both with and without 0.2% of a calcium bentonite clay additive (TX4). After one week, only the combined measure of a broiler productivity index was significantly affected by 1800 µg/kg aflatoxin. However, once birds had consumed treatment diets for two weeks, body weights and relative kidney weights were affected by the lowest concentration. Then, during the third week, body weights, feed conversion, and the productivity index were affected by the 600 µg/kg level. Results also showed that 0.2% TX4 was effective at reducing the accumulation of aflatoxin B1 residues in the liver and improving livability in birds fed aflatoxin. The time required to clear all residues from the liver was less than one week. With evidence that the liver’s ability to process aflatoxin becomes relatively efficient within three weeks, this would imply that an alternative strategy for handling aflatoxin contamination in feed could be to allow a short, punctuated exposure to a higher level, so long as that exposure is followed by at least a week of a withdrawal period on a clean diet free of aflatoxin. PMID:26343723

  1. Evaluation of aluminosilicate compounds to reduce aflatoxin residues and toxicity to poultry and livestock: a review report.

    PubMed

    Harvey, R B; Kubena, L F; Phillips, T D

    1993-01-01

    The aflatoxins (AFs) are reported to be hepatotoxic, mutagenic, immunosuppressive, and carcinogenic. Methods to prevent, reduce, or remediate AF toxicity and residues in the environment are in great demand. Various AF-detoxification procedures are reviewed with particular emphasis on ammoniation and the use of adsorbent compounds to bind AF. A series of in vivo experiments by the authors are reviewed that evaluated the ability of a specific hydrated sodium calcium aluminosilicate (HSCAS) adsorbent to reduce the toxicity of AF to poultry and livestock and to reduce AF residues in milk. These studies showed that HSCAS forms stable bonds with AF in vitro, and when added to AF-contaminated poultry and livestock feeds, HSCAS is able to protect chickens, swine, and lambs from the deleterious toxic effects of AF and to reduce AF residues in milk of dairy cows and goats. These results indicate that HSCAS, when used in conjunction with other mycotoxin management practices, may prove effective for the preventive management of AF-contaminated feedstuffs in livestock and poultry and may reduce AF residues in the food-chain.

  2. Hepatocellular carcinoma and liver cirrhosis TP53 mutation analysis reflects a moderate dietary exposure to aflatoxins in Espírito Santo State, Brazil.

    PubMed

    de Carvalho, Fernanda Magri; de Almeida Pereira, Thiago; Gonçalves, Patrícia Lofego; Jarske, Robson Dettmann; Pereira, Fausto Edmundo Lima; Louro, Iuri Drumond

    2013-08-01

    The close relationship between aflatoxins and 249ser TP53 gene mutation (AGG to AGT, Arg to Ser) in hepatocellular carcinoma (HCC) makes this mutation an indirect indicator of dietary contamination with this toxin. We have examined the prevalence of codon 249 TP53 mutation in 41 HCC and 74 liver cirrhosis (without HCC) cases diagnosed at the HUCAM University Hospital in Vitoria, Espírito Santo State, Brazil. DNA was extracted from paraffin sections and from plasma. The mutation was detected by DNA amplification, followed by restriction endonuclease digestion and confirmed by direct sequencing. DNA restriction showed 249ser mutation in 16 HCC and 13 liver cirrhosis, but sequencing confirmed mutations in only 6 HCC and 1 liver cirrhosis. In addition, sequencing revealed 4 patients with mutations at codon 250 (250ser and 250leu) in HCC cases. The prevalence of TP53 mutation was 10/41 (24.3%) in HCC and 1/74 (1.4%) in liver cirrhosis. No relationship between the presence of mutations and the etiology of HCC was observed. TP53 exon 7 mutations, which are related to aflatoxins exposure, were found at 14.6% (249ser), 7.3% (250leu) and 2.4% (250ser) in 41 cases of HCC and 1.4% in 74 liver cirrhosis (without HCC) cases, suggesting a moderate dietary exposure to aflatoxins in the Espírito Santo State, Brazil.

  3. Probiotic preparation reduces the faecal water genotoxicity in chickens fed with aflatoxin B1 contaminated fodder.

    PubMed

    Slizewska, Katarzyna; Nowak, Adriana; Libudzisz, Zdzislawa; Blasiak, Janusz

    2010-12-01

    The aim of the study was to evaluate the influence of a probiotic preparation on the genotoxicity of faecal water of broiler chickens fed with a fodder contaminated with aflatoxin B(1) (AFB(1)) at 1 or 5mg per kg. Human blood lymphocytes were exposed to chicken's faecal water samples and DNA damage was measured using the comet assay. Genotoxicity of faecal water did not depend on the AFB(1) concentration in the fodder. The mean DNA damage, measured as the percentage of DNA in the tail of the comets, for chickens fed with fodder with AFB(1) at 1 mg/kg was 16.80±0.66, at 5 mg/kg - 16.73±1.51 and in the controls - 12.79±0.66. The supplementation of fodder with the probiotic preparation decreased the extent of DNA damage to 10.02±0.39 for 1 mg/kg AFB(1) and to 11.89±0.72 for 5 mg/kg.

  4. Boric acid: a potential chemoprotective agent against aflatoxin b1 toxicity in human blood

    PubMed Central

    Geyikoglu, Fatime

    2010-01-01

    Aflatoxin B1 is the most potent pulmonary and hepatic carcinogen. Since the eradication of Aflatoxin B1 contamination in agricultural products has been difficult, the use of natural or synthetic free radical scavengers could be a potential chemopreventive strategy. Boric acid is the major component of industry and its antioxidant role has recently been reported. The present study assessed, for the first time, the effectiveness of boric acid following exposure to Aflatoxin B1 on human whole blood cultures. The biochemical characterizations of glutathione and some enzymes have been carried out in erythrocytes. Alterations in malondialdehyde level were determined as an index of oxidative stress. The sister-chromatid exchange and micronucleus tests were performed to assess DNA damages in lymphocytes. Aflatoxin B1 treatment significantly reduced the activities of antioxidants by increasing malondialdehyde level (30.53 and 51.43%) of blood, whereas, the boric acid led to an increased resistance of DNA to oxidative damage induced by Aflatoxin B1 in comparison with control values (P < 0.05). In conclusion, the support of boric acid was especially useful in Aflatoxin-toxicated blood. Thus the risk on tissue targeting of Aflatoxin B1 could be reduced ensuring early recovery from its toxicity. PMID:20431944

  5. Aflatoxins and safe storage.

    PubMed

    Villers, Philippe

    2014-01-01

    The paper examines both field experience and research on the prevention of the exponential growth of aflatoxins during multi-month post-harvest storage in hot, humid countries. The approach described is the application of modern safe storage methods using flexible, Ultra Hermetic™ structures that create an unbreatheable atmosphere through insect and microorganism respiration alone, without use of chemicals, fumigants, or pumps. Laboratory and field data are cited and specific examples are given describing the uses of Ultra Hermetic storage to prevent the growth of aflatoxins with their significant public health consequences. Also discussed is the presently limited quantitative information on the relative occurrence of excessive levels of aflatoxin (>20 ppb) before vs. after multi-month storage of such crops as maize, rice, and peanuts when under high humidity, high temperature conditions and, consequently, the need for further research to determine the frequency at which excessive aflatoxin levels are reached in the field vs. after months of post-harvest storage. The significant work being done to reduce aflatoxin levels in the field is mentioned, as well as its probable implications on post-harvest storage. Also described is why, with some crops such as peanuts, using Ultra Hermetic storage may require injection of carbon dioxide, or use of an oxygen absorber as an accelerant. The case of peanuts is discussed and experimental data is described.

  6. Aflatoxins and safe storage

    PubMed Central

    Villers, Philippe

    2014-01-01

    The paper examines both field experience and research on the prevention of the exponential growth of aflatoxins during multi-month post-harvest storage in hot, humid countries. The approach described is the application of modern safe storage methods using flexible, Ultra Hermetic™ structures that create an unbreatheable atmosphere through insect and microorganism respiration alone, without use of chemicals, fumigants, or pumps. Laboratory and field data are cited and specific examples are given describing the uses of Ultra Hermetic storage to prevent the growth of aflatoxins with their significant public health consequences. Also discussed is the presently limited quantitative information on the relative occurrence of excessive levels of aflatoxin (>20 ppb) before vs. after multi-month storage of such crops as maize, rice, and peanuts when under high humidity, high temperature conditions and, consequently, the need for further research to determine the frequency at which excessive aflatoxin levels are reached in the field vs. after months of post-harvest storage. The significant work being done to reduce aflatoxin levels in the field is mentioned, as well as its probable implications on post-harvest storage. Also described is why, with some crops such as peanuts, using Ultra Hermetic storage may require injection of carbon dioxide, or use of an oxygen absorber as an accelerant. The case of peanuts is discussed and experimental data is described. PMID:24782846

  7. An effective self-control strategy for the reduction of aflatoxin M1 content in milk and to decrease the exposure of consumers.

    PubMed

    Kerekes, Kata; Bonilauri, Paolo; Serraino, Andrea; Giacometti, Federica; Piva, Silvia; Zambrini, Vittorio; Canever, Alessandra; Farkas, Zsuzsa; Ambrus, Árpád

    2016-12-01

    The study reports the results of testing the sensitivity of an early warning sampling plan for detecting milk batches with high aflatoxin AFM1 concentration. The effectiveness of the method was investigated by the analysis of 9017 milk samples collected in Italian milk processing plants that applied control plans with different action limits (AL). For those milk processing plants where 30 ng kg(-1) AL has been applied, the AFM1 contamination was significantly lower at or above the 95th percentile of the milk samples when compared with plants that used 40 ng kg(-1) AL. The results show that the control plan can be used effectively for early warning of occurrence of high AFM1 contamination of milk and to carry out pro-active measures to limit the level of contamination. Estimation of dietary exposure was also carried out, based on the aflatoxin M1 content of the milk samples and on Italian food consumption data. Estimated Daily Intakes (EDI) and Hazard Indices (HI) were calculated for different age groups of the population. HIs show that no adverse effects are expected for the adult population, but in the case of children under age three, the approximate HI values were considerably higher. This underlines the importance of the careful monitoring and control of aflatoxin M1 in milk and dairy products.

  8. Clinical implications of food contaminated by aflatoxins.

    PubMed

    Hendrickse, R G

    1991-01-01

    Aflatoxins have been incriminated, mainly on circumstantial evidence, in hepatocellular carcinoma, acute hepatic failure and Reye's syndrome, but other possible effects of continuous or intermittent dietary exposure to aflatoxins, which occurs widely in the tropics, have received little study. Over the past 10 years evidence has steadily accumulated that incriminates aflatoxins in the aetiology of kwashiorkor, a widespread and serious disorder of children in the tropics, previously believed to be caused by protein deficiency. Investigation of human breast milk, undertaken initially to elucidate the pathogenesis of kwashiorkor in breastfed infants, has revealed widespread and serious exposure to aflatoxins from this source. Extension of these studies to pregnant women, in turn, revealed widespread and serious prenatal aflatoxin exposure. In laboratory and farm animals, such exposure has serious implications for immune and hepatic functions, and is detrimental to growth and development. Recent analysis of heroin samples show that heroin addicts may also be exposed to these toxins. These findings show that human exposure to aflatoxins may begin prenatally, persist during breastfeeding, and continue into adult life. It is postulated that aflatoxins (i) play a role in the aetiology of kwashiorkor, (ii) increase neonatal susceptibility to infection and jaundice, (iii) increase childhood susceptibility to infections and malignant disease, (iv) compromise immune responses to prophylactic immunisations and (v) may play a role in the pathogenesis of diseases in heroin addicts. There are indications also that acute, fatal aflatoxin poisoning which masquerades as 'hepatitis' may occur more frequently than is currently appreciated.

  9. Common African cooking processes do not affect the aflatoxin binding efficacy of refined calcium montmorillonite clay

    PubMed Central

    Elmore, Sarah E.; Mitchell, Nicole; Mays, Travis; Brown, Kristal; Marroquin-Cardona, Alicia; Romoser, Amelia; Phillips, Timothy D.

    2013-01-01

    Aflatoxins are common contaminants of staple crops, such as corn and groundnuts, and a significant cause of concern for food safety and public health in developing countries. Aflatoxin B1 (AFB1) has been implicated in the etiology of acute and chronic disease in humans and animals, including growth stunting, liver cancer and death. Cost effective and culturally acceptable intervention strategies for the reduction of dietary AFB1 exposure are of critical need in populations at high risk for aflatoxicosis. Fermented gruels consisting of cornmeal are a common source for such exposure and are consumed by both children and adults in many countries with a history of frequent, high-level aflatoxin exposure. One proposed method to reduce aflatoxins in the diet is to include a selective enterosorbent, Uniform Particle Size NovaSil (UPSN), as a food additive in contaminated foods. For UPSN to be effective in this capacity, it must be stable in complex, acidic mixtures that are often exposed to heat during the process of fermented gruel preparation. Therefore, the objective of the present study was to test the ability of UPSN to sorb aflatoxin while common cooking conditions were applied. The influence of fermentation, heat treatment, acidity, and processing time were investigated with and without UPSN. Analyses were performed using the field-practical Vicam assay with HPLC verification of trends. Our findings demonstrated that UPSN significantly reduced aflatoxin levels (47-100%) in cornmeal, regardless of processing conditions. Upon comparison of each element tested, time appeared to be the primary factor influencing UPSN efficacy. The greatest decreases in AFB1 were reported in samples allowed to incubate (with or without fermentation) for 72 hrs. This data suggests that addition of UPSN to staple corn ingredients likely to contain aflatoxins would be a sustainable approach to reduce exposure. PMID:24311894

  10. Mycotoxin Contamination in Sugarcane Grass and Juice: First Report on Detection of Multiple Mycotoxins and Exposure Assessment for Aflatoxins B₁ and G₁ in Humans.

    PubMed

    Abdallah, Mohamed F; Krska, Rudolf; Sulyok, Michael

    2016-11-18

    This study was conducted to investigate the natural co-occurrence of multiple toxic fungal and bacterial metabolites in sugarcane grass and juice intended for human consumption in Upper Egypt. Quantification of the target analytes has been done using the "dilute and shoot" approach followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). A total number of 29 and 33 different metabolites were detected in 21 sugarcane grass and 40 juice samples, respectively, with a trend of concentrations being higher in grass than in juice. Among the regulated mycotoxins, only aflatoxin B₁ (AFB₁) and aflatoxin G₁ (AFG₁) were detected. The prevalence of AFB₁ was in 48% of grass samples and in 58% of juice with a maximum concentration of 30.6 μg/kg and 2.10 μg/kg, respectively. AFG₁ was detected in 10% of grass samples (7.76 μg/kg) and 18% of juice samples (34 μg/kg). Dietary exposure was assessed using a juice frequency questionnaire of adult inhabitants in Assiut City. The assessment revealed different levels of exposure to AFB₁ between males and females in winter and summer seasons. The estimated seasonal exposure ranged from 0.20 to 0.40 ng/kg b.w./day in winter and from 0.38 to 0.90 ng/kg b.w./day in summer.

  11. Mycotoxin Contamination in Sugarcane Grass and Juice: First Report on Detection of Multiple Mycotoxins and Exposure Assessment for Aflatoxins B1 and G1 in Humans

    PubMed Central

    Abdallah, Mohamed F.; Krska, Rudolf; Sulyok, Michael

    2016-01-01

    This study was conducted to investigate the natural co-occurrence of multiple toxic fungal and bacterial metabolites in sugarcane grass and juice intended for human consumption in Upper Egypt. Quantification of the target analytes has been done using the “dilute and shoot” approach followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). A total number of 29 and 33 different metabolites were detected in 21 sugarcane grass and 40 juice samples, respectively, with a trend of concentrations being higher in grass than in juice. Among the regulated mycotoxins, only aflatoxin B1 (AFB1) and aflatoxin G1 (AFG1) were detected. The prevalence of AFB1 was in 48% of grass samples and in 58% of juice with a maximum concentration of 30.6 μg/kg and 2.10 μg/kg, respectively. AFG1 was detected in 10% of grass samples (7.76 μg/kg) and 18% of juice samples (34 μg/kg). Dietary exposure was assessed using a juice frequency questionnaire of adult inhabitants in Assiut City. The assessment revealed different levels of exposure to AFB1 between males and females in winter and summer seasons. The estimated seasonal exposure ranged from 0.20 to 0.40 ng/kg b.w./day in winter and from 0.38 to 0.90 ng/kg b.w./day in summer. PMID:27869706

  12. Effects of calcium montmorillonite clay and aflatoxin exposure on dry matter intake, milk production, and milk composition.

    PubMed

    Maki, C R; Thomas, A D; Elmore, S E; Romoser, A A; Harvey, R B; Ramirez-Ramirez, H A; Phillips, T D

    2016-02-01

    Fifteen primiparous crossbred dairy cows that were 114±14d in milk and weighed 533±56kg were used in a replicated 5×5 Latin square to test the efficacy of a calcium montmorillonite clay, NovaSil Plus (NSP; BASF Corp., Ludwigshaven, Germany), for the reduction of aflatoxin (AF) metabolite (AFM1) in milk and the effect of NSP on milk composition. Cows were housed in a freestall barn, fed once a day and milked twice a day. The experiment consisted of five 14-d periods: d 1 through 7 were considered for data collection, and d 8 through 14 were considered a wash-out phase. In each period, cows were randomly assigned to 1 of 5 dietary treatments: (1) control (CON), consisting of a basal total mixed ration (TMR); (2) high-dose NSP diet (NSP-1%), consisting of TMR plus 230 g of NSP; (3) aflatoxin diet (AFD), consisting of the TMR plus AF challenge; (4) low-dose NSP with AF (NSP-0.5%+AFD), composed of TMR plus 115 g of NSP and AF challenge; and (5) high-dose NSP with AF (NSP-1%+AFD), consisting of TMR plus 230 g of NSP and AF challenge. The AF challenge consisted of top dressing a daily dose of 100 µg/kg estimated dry matter intake (DMI); similarly, NSP was fed at 1.0 or 0.5% of estimated DMI. Milk yield and DMI were similar across treatments averaging 21.1±1.33 kg/d and 19.7±0.56 kg/d, respectively. Concentration of milk fat, protein, and lactose were similar across treatments with averages of 4.91±0.20%, 3.85±0.10%, and 4.70±0.06%, respectively. Concentration of vitamin A averaged 0.28±0.03 µg/mL and riboflavin concentration averaged 1.57±0.13 µg/mL across treatments. The concentration of minerals in milk were similar for all treatments. Cows fed CON and NSP-1% yielded the lowest concentration of AFM1 in milk with 0.03 and 0.01±0.06 µg/L. Addition of NSP reduced milk AFM1 from 1.10±0.06 µg/L with the AF diet to 0.58 and 0.32±0.06 µg/L with the NSP-0.5%+AF and NSP-1%+AF diets, respectively. Excretion of AFM1 was reduced by NSP; mean values were 24.38, 11

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

    PubMed

    Robinson, A; Johnson, N M; Strey, A; Taylor, J F; Marroquin-Cardona, A; Mitchell, N J; Afriyie-Gyawu, E; Ankrah, N A; Williams, J H; Wang, J S; Jolly, P E; Nachman, R J; Phillips, T D

    2012-01-01

    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.

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

    PubMed Central

    Robinson, A.; Johnson, N.M.; Strey, A.; Taylor, J.F.; Marroquin-Cardona, A.; Mitchell, N.J.; Afriyie-Gyawu, E.; Ankrah, N.A.; Williams, J.H.; Wang, J.S.; Jolly, P.E.; Nachman, R.J.; Phillips, T.D.

    2012-01-01

    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 analyzed (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 esophageal cancer in humans. PMID:22324939

  15. Effects of calcium montmorillonite clay and aflatoxin exposure on dry matter intake, milk production, and milk composition

    USDA-ARS?s Scientific Manuscript database

    Fifteen primiparous crossbred dairy cows that were 114 ± 14 d in milk and weighed 533 ± 56 kg were used in a replicated 5×5 Latin square to test the efficacy of NovaSil Plus (NSP) for the reduction of aflatoxin (AF) metabolite (AFM1) in milk and the effect of NSP on milk composition. Cows were hous...

  16. How does airway exposure of aflatoxin B1 affect serum albumin adduct concentrations? Evidence based on epidemiological study and animal experimentation.

    PubMed

    Mo, Xianwei; Lai, Hao; Yang, Yang; Xiao, Jun; He, Ke; Liu, Chao; Chen, Jiansi; Lin, Yuan

    2014-08-01

    Aflatoxin B1 (AFB1) airway inhalation represents an additional route of exposure to this toxin. However, the association between AFB1 inhalation and serum AFB1 albumin adducts remains unclear. The aim of this study was to explore the association between airway exposure to AFB1 and serum AFB1 albumin adduct concentrations via an epidemiological study, as well as in an AFB1 airway exposure animal model. Our epidemiological study was conducted in a sugar factory in the Guangxi Autonomous Region of China. In order to examine fungal contamination, air samples were obtained in the workshop and areas outside the workshop, such as the office and nearby store. Dust samples were also collected from the bagasse warehouse and presser workshop, and were analyzed using an indirect competitive enzyme-linked immunosorbent assay (ELISA). Additionally, blood samples were collected from a total of 121 workshop workers, and a control group (n = 80) was comprised of workers who undertook administrative tasks or other work outside the workshop. The animal experiment was conducted in the laboratory animal center of Guangxi Medical University, where a total of 60 adult male rabbits were involved in this study. By intubation, AFB1 was administered in three groups of rabbits daily, at dose rates of 0.075, 0.05 and 0.025 mg/kg/day for a period of 7 days. Blood samples were collected on day 1, day 3, day 7 and day 21, and the measurements of the AFB1 albumin adducts in the serum were performed by a double antibody sandwich ELISA. The epidemiological study showed that serum albumin adducts were detected in 67 workshop workers (55.37%), and the values ranged 6.4 pg/mg albumin to 212 pg/mg albumin (mean value: 51 ± 4.62 pg/mg albumin). In contrast, serum albumin adducts were detected in only 7 control group participants, with the values ranging from 9 pg AFB1/mg albumin to 59 pg/mg albumin (mean value: 20 ± 13.72 pg/mg albumin). The animal experiment revealed that the rabbits had detectable

  17. The efficacy of raw and concentrated bentonite clay in reducing the toxic effects of aflatoxin in broiler chicks.

    PubMed

    Shannon, T A; Ledoux, D R; Rottinghaus, G E; Shaw, D P; Dakovic, A; Markovic, M

    2017-06-01

    The objective of this study was to evaluate the efficacy of two adsorbents, a raw bentonite clay (RC) and a concentrated bentonite clay (CC), in ameliorating the toxic effects of aflatoxin B1 (AFB1). Results of the in vitro study (pH 3.0) indicated the CC adsorbed more AFB1 than RC (93.39 mg/g vs. 79.30 mg/g) suggesting that CC may be more effective than RC in reducing the toxic effects of AFB1. One hundred and eighty day-old straight run broiler chicks were assigned to 6 replicate pens of 5 chicks each and assigned to 6 dietary treatments from hatch to day 21. Dietary treatments included: 1) basal diet (BD) containing no AFB1 or adsorbents; 2) BD plus 0.50% RC; 3) BD plus 0.50% CC; 4) BD plus 2.0 mg AFB1/kg; 5) BD plus 2.0 mg AFB1/kg plus 0.50% RC; and 6) BD plus 2.0 mg AFB1/kg plus 0.50% CC. Dietary AFB1 concentrations were confirmed by analysis and diets were screened for other mycotoxins prior to the start of the experiment. The addition of AFB1 to the feed reduced (P < 0.05) growth performance and increased (P < 0.05) relative liver weight (RLW) and kidney weight (RKW) of chicks fed AFB1 compared to control chicks on day 21. These changes were ameliorated (P < 0.05) by the addition of RC and CC to the AFB1 diet. Mild to moderate lesions of aflatoxicosis (2.25) were observed in chicks fed AFB1 alone on day 21. The addition of both RC and CC to the AFB1 diet decreased (P < 0.05) but did not prevent liver lesions (0.92 and 1.42, respectively). Results indicate that both RC and CC were effective in reducing the toxic effects of AFB1, however the cost of processing of CC would make the RC a more economical product for reducing the effects of AFB1 in young broiler chicks. © 2016 Poultry Science Association Inc.

  18. Challenges facing the biological control strategy for eliminating aflatoxin contamination

    USDA-ARS?s Scientific Manuscript database

    Competition with Aspergillus flavus isolates incapable of aflatoxin production is currently the most widely used biocontrol method for reducing aflatoxin contamination of in maize and cottonseed where aflatoxin contamination is a persistent problem for human and animal health. The method involves sp...

  19. Natural postharvest aflatoxin occurrence in food legumes in the smallholder farming sector of Zimbabwe.

    PubMed

    Maringe, David Tinayeshe; Chidewe, Cathrine; Benhura, Mudadi Albert; Mvumi, Brighton Marimanzi; Murashiki, Tatenda Clive; Dembedza, Mavis Precious; Siziba, Lucia; Nyanga, Loveness Kuziwa

    2017-03-01

    Aflatoxins, mainly produced by Aspergillus flavus and Aspergillus parasiticus, are highly toxic and may lead to health problems such as liver cancer. Exposure to aflatoxins may result from ingestion of contaminated foods. Levels of AFB1, AFB2, AFG1 and AFG2 in samples of groundnuts (Arachis hypogaea), beans (Phaseolus vulgaris), cowpeas (Vigna unguiculata) and bambara nuts (Vigna subterranean) grown by smallholder farmers in Shamva and Makoni districts, Zimbabwe, were determined at harvesting, using high performance liquid chromatography after immunoaffinity clean-up. Aflatoxins were detected in 12.5% of groundnut samples with concentrations ranging up to 175.9 µg/kg. Aflatoxins were present in 4.3% of the cowpea samples with concentrations ranging from 1.4 to 103.4 µg/kg. Due to alarming levels of aflatoxins detected in legumes versus maximum permissible levels, there is a need to assist smallholder farmers to develop harvest control strategies to reduce contamination of aflatoxins in legumes.

  20. Effect of almond processing on levels and distribution of aflatoxins in finished products and byproducts.

    PubMed

    Zivoli, Rosanna; Gambacorta, Lucia; Perrone, Giancarlo; Solfrizzo, Michele

    2014-06-18

    The fate of aflatoxins during processing of contaminated almonds into nougat, pastries, and almond syrup was evaluated by testing the effect of each processing step (blanching, peeling, roasting, caramelization, cooking, and water infusion) on the distribution and levels of aflatoxins. Blanching and peeling did not reduce total aflatoxins that were distributed between peeled almonds (90-93%) and skins (7-10%). Roasting of peeled almonds reduced up to 50% of aflatoxins. Up to 70% reduction of aflatoxins was observed during preparation and cooking of almond nougat in caramelized sugar. Aflatoxins were substantially stable during preparation and cooking of almond pastries. The whole process of almond syrup preparation produced a marked increase of total aflatoxins (up to 270%) that were distributed between syrup (18-25%) and spent almonds (75-82%). The increase of total aflatoxins was probably due to the activation of almond enzymes during the infusion step that released free aflatoxins from masked aflatoxins.

  1. Aflatoxins, hepatocellular carcinoma and public health

    PubMed Central

    Magnussen, Arvin; Parsi, Mansour A

    2013-01-01

    Hepatocellular carcinoma (HCC) is one of the leading causes of cancer deaths worldwide, primarily affecting populations in the developing countries. Aflatoxin, a food contaminant produced by the fungi Aspergillus flavus and Aspergillus parasiticus, is a known human carcinogen that has been shown to be a causative agent in the pathogenesis of HCC. Aflatoxin can affect a wide range of food commodities including corns, oilseeds, spices, and tree nuts as well as milk, meat, and dried fruit. Many factors affect the growth of Aspergillus fungi and the level of aflatoxin contamination in food. Drought stress is one of the factors that increase susceptibility of plants to Aspergillus and thus aflatoxin contamination. A recent drought is thought to be responsible for finding of trace amounts of aflatoxin in some of the corn harvested in the United States. Although it’s too soon to know whether aflatoxin will be a significant problem, since United States is the world’s largest corn producer and exporter, this has raised alarm bells. Strict regulations and testing of finished foods and feeds in the United States should prevent a major health scare, and prevent human exposure to deleterious levels of aflatoxin. Unfortunately, such regulations and testing are not in place in many countries. The purpose of this editorial is to summarize the current knowledge on association of aflatoxin and HCC, encourage future research and draw attention to this global public health issue. PMID:23539499

  2. Aflatoxins, hepatocellular carcinoma and public health.

    PubMed

    Magnussen, Arvin; Parsi, Mansour A

    2013-03-14

    Hepatocellular carcinoma (HCC) is one of the leading causes of cancer deaths worldwide, primarily affecting populations in the developing countries. Aflatoxin, a food contaminant produced by the fungi Aspergillus flavus and Aspergillus parasiticus, is a known human carcinogen that has been shown to be a causative agent in the pathogenesis of HCC. Aflatoxin can affect a wide range of food commodities including corns, oilseeds, spices, and tree nuts as well as milk, meat, and dried fruit. Many factors affect the growth of Aspergillus fungi and the level of aflatoxin contamination in food. Drought stress is one of the factors that increase susceptibility of plants to Aspergillus and thus aflatoxin contamination. A recent drought is thought to be responsible for finding of trace amounts of aflatoxin in some of the corn harvested in the United States. Although it's too soon to know whether aflatoxin will be a significant problem, since United States is the world's largest corn producer and exporter, this has raised alarm bells. Strict regulations and testing of finished foods and feeds in the United States should prevent a major health scare, and prevent human exposure to deleterious levels of aflatoxin. Unfortunately, such regulations and testing are not in place in many countries. The purpose of this editorial is to summarize the current knowledge on association of aflatoxin and HCC, encourage future research and draw attention to this global public health issue.

  3. Reduced Foodborne Toxin Exposure Is a Benefit of Improving Dietary Diversity

    PubMed Central

    Wu, Felicia; Mitchell, Nicole J.; Male, Denis; Kensler, Thomas W.

    2014-01-01

    Naturally occurring foodborne toxins are common in subsistence diets of low-income human populations worldwide. Often, these populations rely on one or two staple foods for the bulk of their calories, making them more susceptible to chronic intake of certain toxins. Exposure to common foodborne toxins is associated with diverse conditions such as cancer, immunotoxicity, growth impairment, and neurological deficits. Interventions focused solely on reducing toxin levels have proven difficult to sustain. Using case studies of two foodborne toxins, aflatoxin and cassava cyanide, this article addresses the heightened risk of particular diseases from eating monotonous diets based in maize, groundnuts, and cassava: common in sub-Saharan Africa and parts of Asia. We also discuss the potential role of increased dietary diversity in counteracting these diseases. Increased dietary diversity can reduce consumption of toxins and increase intake of nutrients that could counteract the toxicity of such chemicals. In Qidong, China, a population that previously consumed a monotonous maize-based diet and increased dietary diversity since the 1980s has experienced a dramatic reduction in liver cancer mortalities. That liver cancer decreased as dietary diversity increased is the catalyst for the hypothesis that dietary diversity could have a direct impact on reducing health effects of foodborne toxins. Future research, agricultural development, and food policy reforms should take into consideration the multifaceted benefits associated with improved dietary diversity. Collaborations between toxicologists, nutritionists, and policymakers are important to development of sustainable interventions to reduce foodborne toxin exposure and promote health through increased dietary diversity. PMID:25015663

  4. Prenatal exposure of mice to the human liver carcinogen aflatoxin B1 reveals a critical window of susceptibility to genetic change.

    PubMed

    Chawanthayatham, Supawadee; Thiantanawat, Apinya; Egner, Patricia A; Groopman, John D; Wogan, Gerald N; Croy, Robert G; Essigmann, John M

    2015-03-15

    It has become axiomatic that critical windows of susceptibility to genotoxins exist and that genetic damage in utero may be a trigger for later life cancers. Data supporting this critical window hypothesis are remarkably few. This study provides a quantitative bridge between DNA damage by the liver carcinogen aflatoxin B1 (AFB1 ) during prenatal development and the risk of later life genetic disease. AFB1 was given to pregnant C57BL/6J mice, carrying F1 gestation day 14 (GD14) embryos of the B6C3F1 genotype. Ultra-high performance liquid chromatography and mass spectrometry (UPLC-MS) using aflatoxin-(15) N5 -guanine adduct standards afforded measurement of the AFB1 -N(7) -Gua and AFB1 -FAPY adducts 6-hr post dosing in liver DNA of mothers and embryos. A parallel cohort gave birth and the livers of the F1 were analyzed for mutations in the gpt gene at 3 and 10 weeks of age. The data revealed mutational spectra dominated by G:C to T:A mutations in both the mother and offspring that are characteristic of AFB1 and distinct from background. It was shown that adducts in GD14 embryos were 20-fold more potent inducers of mutagenesis than adducts in parallel-dosed adults. This sensitivity enhancement correlated with Ki67 staining of the liver, reflecting the proliferative potential of the tissue. Taken together, these data provide insight into the relative genetic risks of prenatal and adult exposures to AFB1 . Early life exposure, especially during the embryonic period, is strikingly more mutagenic than treatment later in life. Moreover the data provide a baseline against which risk prevention strategies can be evaluated.

  5. The effect of dietary aflatoxin on wild turkey poults.

    PubMed

    Quist, C F; Bounous, D I; Kilburn, J V; Nettles, V F; Wyatt, R D

    2000-07-01

    Aflatoxins, toxic metabolites of Aspergillus flavus or Aspergillus parasiticus, cause poor feed utilization, decreased weight gains, depressed immune function, liver dysfunction, coagulation abnormalities, and death in a wide variety of species including humans. Conservationists have become concerned that increasingly popular wildlife feeding or baiting practices could expose wildlife to toxic amounts of aflatoxin-contaminated grains. In particular, the effects of aflatoxins on the wild turkey (Meleagris gallopova silvestris) are of concern because the conspecific domestic turkey is highly susceptible to aflatoxins. To evaluate the effect of dietary aflatoxin on wild turkeys, four groups of 4-mo-old wild turkeys were fed diets containing either 0, 100, 200, or 400 micrograms aflatoxin/kg feed for 2 wk in September and October 1996. Aflatoxin-fed poults had decreased feed consumption and weight gains as compared with control poults. Decreased liver-to-body weight ratios, liver enzyme alterations, slightly altered blood coagulation patterns, and mild histologic changes indicated low-level liver damage. Compromise of cell-mediated immunity was indicated by decreased lymphoblast transformation. The effects were apparent in all treatment groups to variable levels, but significant differences most often were found at 400 micrograms aflatoxin/kg feed. This study shows that short-term aflatoxin ingestion by wild turkeys can induce undesirable physiologic changes; therefore, exposure of wild turkeys to feeds containing aflatoxin levels of 100 micrograms aflatoxin/kg feed or more should be avoided.

  6. The role of aflatoxins and hepatitis viruses in the etiopathogenesis of hepatocellular carcinoma: A basis for primary prevention in Guinea-Conakry, West Africa.

    PubMed

    Turner, Paul C; Sylla, Abdoulaye; Diallo, Mamadou S; Castegnaro, Jean-Jacques; Hall, Andrew J; Wild, Christopher P

    2002-12-01

    Aflatoxins and hepatitis B virus (HBV) are major risk factors for hepatocellular carcinoma (HCC) in South-east Asia and Africa, parts of the world where this cancer is most prevalent. Exposure to both factors is endemic, occurring from early in life. There is evidence from both epidemiological studies and animal models that the two factors can act synergistically to increase the risk of HCC, but the underlying cellular and molecular mechanisms of interaction are as yet undefined. One possibility suggested by studies in HBV transgenic mice is that chronic liver injury alters the expression of carcinogen metabolizing enzymes, thus modulating the level of binding of aflatoxin to DNA. Primary prevention of HCC in high incidence areas of the world should primarily be focused on provision of the safe, effective vaccine against HBV. However, measures to reduce the high levels of aflatoxin exposure, where chronic HBV infection is currently epidemic, would also significantly contribute to reducing HCC incidence. In Guinea-Conakry, West Africa, surveys of HBV infection and aflatoxin exposure have established baseline data for the implementation of a community-based intervention study. This study will evaluate the effectiveness of improving the post-harvest processing and storage of the groundnut crop, a major source of aflatoxins, using aflatoxin-albumin adducts as the outcome measurement. Copyright 2002 Blackwell Publishing Asia Pty Ltd

  7. Effects of reduced mitochondrial DNA content on secondary mitochondrial toxicant exposure in Caenorhabditis elegans

    PubMed Central

    Luz, Anthony L.

    2016-01-01

    The mitochondrial genome (mtDNA) is intimately linked to cellular and organismal health, as demonstrated by the fact that mutations in and depletion of mtDNA result in severe mitochondrial disease in humans. However, cells contain hundreds to thousands of copies of mtDNA, which provides genetic redundancy, and creates a threshold effect in which a large percentage of mtDNA must be lost prior to clinical pathogenesis. As certain pharmaceuticals and genetic mutations can result in depletion of mtDNA, and as many environmental toxicants target mitochondria, it is important to understand whether reduced mtDNA will sensitize an individual to toxicant exposure. Here, using ethidium bromide (EtBr), which preferentially inhibits mtDNA replication, we reduced mtDNA 35-55% in the in vivo model organism Caenorhabditis elegans. Chronic, lifelong, low-dose EtBr exposure did not disrupt nematode development or lifespan, and induced only mild alterations in mitochondrial respiration, while having no effect on steady-state ATP levels. Next, we exposed nematodes with reduced mtDNA to the known and suspected mitochondrial toxicants aflatoxin B1, arsenite, paraquat, rotenone or ultraviolet C radiation (UVC). EtBr pre-exposure resulted in mild sensitization of nematodes to UVC and arsenite, had no effect on AfB1 and paraquat, and provided some protection from rotenone toxicity. These mixed results provide a first line of evidence suggesting that reduced mtDNA content may sensitize an individual to certain environmental exposures. PMID:27566481

  8. Effects of reduced mitochondrial DNA content on secondary mitochondrial toxicant exposure in Caenorhabditis elegans.

    PubMed

    Luz, Anthony L; Meyer, Joel N

    2016-09-01

    The mitochondrial genome (mtDNA) is intimately linked to cellular and organismal health, as demonstrated by the fact that mutations in and depletion of mtDNA result in severe mitochondrial disease in humans. However, cells contain hundreds to thousands of copies of mtDNA, which provides genetic redundancy, and creates a threshold effect in which a large percentage of mtDNA must be lost prior to clinical pathogenesis. As certain pharmaceuticals and genetic mutations can result in depletion of mtDNA, and as many environmental toxicants target mitochondria, it is important to understand whether reduced mtDNA will sensitize an individual to toxicant exposure. Here, using ethidium bromide (EtBr), which preferentially inhibits mtDNA replication, we reduced mtDNA 35-55% in the in vivo model organism Caenorhabditis elegans. Chronic, lifelong, low-dose EtBr exposure did not disrupt nematode development or lifespan, and induced only mild alterations in mitochondrial respiration, while having no effect on steady-state ATP levels. Next, we exposed nematodes with reduced mtDNA to the known and suspected mitochondrial toxicants aflatoxin B1, arsenite, paraquat, rotenone or ultraviolet C radiation (UVC). EtBr pre-exposure resulted in mild sensitization of nematodes to UVC and arsenite, had no effect on AfB1 and paraquat, and provided some protection from rotenone toxicity. These mixed results provide a first line of evidence suggesting that reduced mtDNA content may sensitize an individual to certain environmental exposures. Copyright © 2016 Elsevier B.V. and Mitochondria Research Society. All rights reserved.

  9. Cytotoxic and genotoxic evaluation of tortillas produced by microwave heating during alkaline-cooking of aflatoxin-contaminated maize.

    PubMed

    Vázquez-Durán, Alma; Díaz-Torres, Roberto; Ramírez-Noguera, Patricia; Moreno-Martínez, Ernesto; Méndez-Albores, Abraham

    2014-05-01

    In vitro cytotoxicity and genotoxicity induction by aflatoxin B1 (AFB1) from maize (ME) and tortillas (TE) produced by microwave nixtamalization were investigated in monkey kidney (Vero cells) using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, the induction of lipid peroxidation, the oxidative damage by means of glutathione (GSH) depletion, and the Salmonella-microsomal screening system (Ames test). Our results showed that, at higher concentrations, both ME and TE extracts that contained varying amounts of aflatoxin caused a considerable decrease in Vero cell viability (up to 37%) after 4 h of exposure. Aflatoxins from ME induced greater oxidative damage by enhancing lipid peroxidation (up to 6.05 ± 0.14 μmol/mg protein) as compared to TE; however, TE also induced significant malondialdehyde formation in particular at the higher aflatoxin concentration tested (up to 2.7 ± 0.19 μmol/mg protein). The decrease in GSH level was also more pronounced in ME as compared to TE. Moreover, the Ames test results indicated that the mutagenic activity of TE was greatly reduced compared with that of ME based on his(-) → his(+) reversions in the Salmonella TA100 strain. According to these results, it is concluded that the microwave nixtamalization procedure reduced aflatoxins and their in vitro toxicity and mutagenic activity. In Mexico, aflatoxins are often found in maize destined for the tortilla industry; consequently, tortilla consumption invariably leads to an important intake of intact and/or modified aflatoxin molecules caused by the thermal-alkaline treatment used during production. Therefore, it is of the highest importance to check whether such intake has the potential to lead to higher risk for adverse human health effects. In view of these considerations, in vitro tests may thus be useful for predicting the potential cytotoxicity and genotoxicity of tortillas produced for human consumption using aflatoxin-contaminated maize. © 2014

  10. Sequential dietary exposure to aflatoxin B1 and fumonisin B1 in F344 rats increases liver preneoplastic changes indicative of a synergistic interaction.

    PubMed

    Qian, Guoqing; Tang, Lili; Lin, Shuhan; Xue, Kathy S; Mitchell, Nicole J; Su, Jianjia; Gelderblom, Wentzel C; Riley, Ronald T; Phillips, Timothy D; Wang, Jia-Sheng

    2016-09-01

    Dietary co-exposure to aflatoxin B1 (AFB1) and fumonisin B1 (FB1) and their interaction on hepatocellular carcinogenesis is of particular concern in toxicology and public health. In this study we evaluated the liver preneoplastic effects of single and sequential dietary exposure to AFB1 and FB1 in the F344 rat carcinogenesis model. Serum biochemical alterations, liver histopathological changes, and the formation of liver glutathione S transferase positive (GST-P+) foci were the major outcome parameters examined. Compared to the AFB1-only treatment, the FB1-only treatment induced less dysplasia, and more apoptosis and mitoses. Sequential AFB1 and FB1 treatment lead to increased numbers of dysplasia, apoptosis and foci of altered hepatocytes, as compared to either mycotoxin treatment alone. More importantly, sequential exposure to AFB1 and FB1 synergistically increased the numbers of liver GTP-P+ foci by approximately 7.3-and 12.9-fold and increased the mean sizes of GST-P+ foci by 6- and 7.5-fold, respectively, as compared to AFB1- or FB1-only treatment groups. In addition, liver ALT and AST levels were significantly increased after sequential treatment as compared to single treatment groups. The results demonstrate the interactive effect of dietary AFB1 and FB1 in inducing liver GST-P+ foci formation and provide information to model future intervention studies.

  11. Quantitative correlation of aflatoxin biomarker with dietary intake of aflatoxin in Tanzanian children.

    PubMed

    Routledge, Michael N; Kimanya, Martin E; Shirima, Candida P; Wild, Christopher P; Gong, Yun Yun

    2014-08-01

    The association between aflatoxin intake from maize-based weaning food and aflatoxin albumin adducts (AF-alb) was investigated in 148 Tanzanian children aged between 12 and 22 months, at 2 visits 6 months apart. At the first visit (storage season) there was a significant correlation at the individual level between AF-alb (geometric mean 43.2 pg/mg albumin) and aflatoxin intake (geometric mean 81.7 ng/kg b.w./d) through maize-based weaning food (r = 0.51, p < 0.01). Overall, this correlation was r = 0.43 (p < 0.01). The AF-alb level in weaning-age children in Tanzania closely reflects aflatoxin intake from maize in weaning food. Exposure levels suggest children may be at risk from aflatoxin associated health effects.

  12. Genetic Features of Aflatoxin-Associated Hepatocellular Carcinoma.

    PubMed

    Zhang, Weilong; He, Huan; Zang, Mengya; Wu, Qifeng; Zhao, Hong; Lu, Ling-Ling; Ma, Peiqing; Zheng, Hongwei; Wang, Nengjin; Zhang, Ying; He, Siyuan; Chen, Xiaoyan; Wu, Zhiyuan; Wang, Xiaoyue; Cai, Jianqiang; Liu, Zhihua; Sun, Zongtang; Zeng, Yi-Xin; Qu, Chunfeng; Jiao, Yuchen

    2017-07-01

    Dietary exposure to aflatoxin is an important risk factor for hepatocellular carcinoma (HCC). However, little is known about the genomic features and mutations of aflatoxin-associated HCCs compared with HCCs not associated with aflatoxin exposure. We investigated the genetic features of aflatoxin-associated HCC that can be used to differentiate them from HCCs not associated with this carcinogen. We obtained HCC tumor tissues and matched non-tumor liver tissues from 49 patients, collected from 1990 through 2016, at the Qidong Liver Cancer Hospital Institute in China-a high-risk region for aflatoxin exposure (38.2% of food samples test positive for aflatoxin contamination). Somatic variants were identified using GATK Best Practices Pipeline. We validated part of the mutations from whole-genome sequencing and whole-exome sequencing by Sanger sequencing. We also analyzed genomes of 1072 HCCs, obtained from 5 datasets from China, the United States, France, and Japan. Mutations in 49 aflatoxin-associated HCCs and 1072 HCCs from other regions were analyzed using the Wellcome Trust Sanger Institute mutational signatures framework with non-negative matrix factorization. The mutation landscape and mutational signatures from the aflatoxin-associated HCC and HCC samples from general population were compared. We identified genetic features of aflatoxin-associated HCC, and used these to identify aflatoxin-associated HCCs in datasets from other regions. Tumor samples were analyzed by immunohistochemistry to determine microvessel density and levels of CD34 and CD274 (PD-L1). Aflatoxin-associated HCCs frequently contained C>A transversions, the sequence motif GCN, and strand bias. In addition to previously reported mutations in TP53, we found frequent mutations in the adhesion G protein-coupled receptor B1 gene (ADGRB1), which were associated with increased capillary density of tumor tissue. Aflatoxin-associated HCC tissues contained high-level potential mutation

  13. Up-regulation of nucleotide excision repair in mouse lung and liver following chronic exposure to aflatoxin B{sub 1} and its dependence on p53 genotype

    SciTech Connect

    Mulder, Jeanne E.; Bondy, Genevieve S.; Mehta, Rekha; Massey, Thomas E.

    2014-03-01

    Aflatoxin B{sub 1} (AFB{sub 1}) is biotransformed in vivo into an epoxide metabolite that forms DNA adducts that may induce cancer if not repaired. p53 is a tumor suppressor gene implicated in the regulation of global nucleotide excision repair (NER). Male heterozygous p53 knockout (B6.129-Trp53{sup tm1Brd}N5, Taconic) and wild-type mice were exposed to 0, 0.2 or 1.0 ppm AFB{sub 1} for 26 weeks. NER activity was assessed with an in vitro assay, using AFB{sub 1}-epoxide adducted plasmid DNA as a substrate. For wild-type mice, repair of AFB{sub 1}–N7-Gua adducts was 124% and 96% greater in lung extracts from mice exposed to 0.2 ppm and 1.0 ppm AFB{sub 1} respectively, and 224% greater in liver extracts from mice exposed to 0.2 ppm AFB{sub 1} (p < 0.05). In heterozygous p53 knockout mice, repair of AFB{sub 1}–N7-Gua was only 45% greater in lung extracts from mice exposed to 0.2 ppm AFB{sub 1} (p < 0.05), and no effect was observed in lung extracts from mice treated with 1.0 ppm AFB{sub 1} or in liver extracts from mice treated with either AFB{sub 1} concentration. p53 genotype did not affect basal levels of repair. AFB{sub 1} exposure did not alter repair of AFB{sub 1}-derived formamidopyrimidine adducts in lung or liver extracts of either mouse genotype nor did it affect XPA or XPB protein levels. In summary, chronic exposure to AFB{sub 1} increased NER activity in wild-type mice, and this response was diminished in heterozygous p53 knockout mice, indicating that loss of one allele of p53 limits the ability of NER to be up-regulated in response to DNA damage. - Highlights: • Mice are chronically exposed to low doses of the mycotoxin aflatoxin B{sub 1} (AFB{sub 1}). • The effects of AFB{sub 1} and p53 status on nucleotide excision repair are investigated. • AFB{sub 1} increases nucleotide excision repair in wild type mouse lung and liver. • This increase is attenuated in p53 heterozygous mouse lung and liver. • Results portray the role of p53 in

  14. Degradation of aflatoxin B1 from naturally contaminated maize using the edible fungus Pleurotus ostreatus.

    PubMed

    Jackson, Lauren W; Pryor, Barry M

    2017-12-01

    Aflatoxins are highly carcinogenic secondary metabolites that can contaminate approximately 25% of crops and that cause or exacerbate multiple adverse health conditions, especially in Sub-Saharan Africa and South and Southeast Asia. Regulation and decontamination of aflatoxins in high exposure areas is lacking. Biological detoxification methods are promising because they are assumed to be cheaper and more environmentally friendly compared to chemical alternatives. White-rot fungi produce non-specific enzymes that are known to degrade aflatoxin in in situ and ex situ experiments. The aims of this study were to (1) decontaminate aflatoxin B1 (AFB1) in naturally contaminated maize with the edible, white-rot fungus Pleurotus ostreatus (oyster mushroom) using a solid-state fermentation system that followed standard cultivation techniques, and to (2) and to assess the risk of mutagenicity in the resulting breakdown products and mushrooms. Vegetative growth and yield characteristics of P. ostreatus were not inhibited by the presence of AFB1. AFB1 was degraded by up to 94% by the Blue strain. No aflatoxin could be detected in P. ostreatus mushrooms produced from AFB1-contaminated maize. Moreover, the mutagenicity of breakdown products from the maize substrate, and reversion of breakdown products to the parent compound, were minimal. These results suggest that P. ostreatus significantly degrades AFB1 in naturally contaminated maize under standard cultivation techniques to levels that are acceptable for some livestock fodder, and that using P. ostreatus to bioconvert crops into mushrooms can reduce AFB1-related losses.

  15. Impact of maximum levels in European legislation on exposure of mycotoxins in dried products: case of aflatoxin B1 and ochratoxin A in nuts and dried fruits.

    PubMed

    Van de Perre, Evelien; Jacxsens, Liesbeth; Lachat, Carl; El Tahan, Fouad; De Meulenaer, Bruno

    2015-01-01

    In this study the impact of setting European criteria on exposure to aflatoxin B1 via nuts and figs and ochratoxin A via dried fruits is evaluated for the Belgian population, as an example of the European population. Two different scenarios were evaluated. In scenario 1 all collected literature data are considered, assuming that there is no border control nor legal limits in Europe. In the second scenario, contamination levels above the maximum limits are excluded. The results from scenario 1 demonstrated that if no regulation is in place, AFB1 and OTA concentrations reported in the analysed food can have potential health risk to the population. The estimated exposure of OTA for scenario 2 is below the TDI of 5 ng/kg BW⋅day, indicating that OTA concentrations accepted by EU legislation pose a low risk to the Belgian population. For AFB1, the MOE values of scenario 2 are above 10,000 and can be considered to be of low health concern, based on BDML10 for humans, except for figs (MOE = 5782). This means that for all matrices, with exception of figs, the maximum values of AFB1 in the European legislation are sufficient to be of a low health concern for consumers.

  16. Regulatory considerations of aflatoxin contamination of food in Mexico.

    PubMed

    Guzmán-de-Peña, Doralinda; Peña-Cabriales, Juan José

    2005-01-01

    Aflatoxins are potent mutagenic and carcinogenic compounds produced by some strains of Aspergillus flavus, A. nomius, and A. parasiticus that are commonly present in the environment. Human populations, particularly those whose basic diet includes grains, are in risk to exposure to aflatoxins. It is thus necessary to monitor and control the contamination of food and feed by aflatoxins in both domestic and international trade. As large amounts of corn are imported into Mexico from the United States, this paper stresses the need to develop legislation and enforce standards to ensure trade of corn with the minimal amount of aflatoxin.

  17. Potential of lactic acid bacteria in aflatoxin risk mitigation.

    PubMed

    Ahlberg, Sara H; Joutsjoki, Vesa; Korhonen, Hannu J

    2015-08-17

    Aflatoxins (AF) are ubiquitous mycotoxins contaminating food and feed. Consumption of contaminated food and feed can cause a severe health risk to humans and animals. A novel biological method could reduce the health risks of aflatoxins through inhibiting mold growth and binding aflatoxins. Lactic acid bacteria (LAB) are commonly used in fermented food production. LAB are known to inhibit mold growth and, to some extent, to bind aflatoxins in different matrices. Reduced mold growth and aflatoxin production may be caused by competition for nutrients between bacterial cells and fungi. Most likely, binding of aflatoxins depends on environmental conditions and is strain-specific. Killed bacteria cells possess consistently better binding abilities for aflatoxin B1 (AFB1) than viable cells. Lactobacilli especially are relatively well studied and provide noticeable possibilities in binding of aflatoxin B1 and M1 in food. It seems that binding is reversible and that bound aflatoxins are released later on (Haskard et al., 2001; Peltonen et al., 2001). This literature review suggests that novel biological methods, such as lactic acid bacteria, show potential in mitigating toxic effects of aflatoxins in food and feed.

  18. Aflatoxin B1 albumin adducts in plasma and aflatoxin M1 in urine are associated with plasma concentrations of vitamins A and E

    PubMed Central

    Obuseh, Francis A.; Jolly, Pauline E.; Jiang, Yi; Shuaib, Faisal M. B.; Waterbor, John; Ellis, William O.; Piyathilake, Chandrika J.; Desmond, Renee A.; Afriyie-Gyawu, Evans; Phillips, Timothy D.

    2011-01-01

    Background Although aflatoxin exposure has been shown to be associated with micronutrient deficiency in animals, there are few investigations on the effects of aflatoxin exposure on micronutrient metabolism in humans. Objective To examine the relationship between aflatoxin B1 (AFB1) albumin adducts (AF-ALB) in plasma and the aflatoxin M1 (AFM1) metabolite in urine and plasma concentrations of retinol (vitamin A) and α-tocopherol (vitamin E) in Ghanaians. Methods A cross-sectional study of 147 adult participants was conducted. Blood and urine samples were tested for aflatoxin and vitamins A and E levels. Results Multivariable analysis showed that participants with high AF-ALB (≥ 0.80 pmol/mg albumin) had increased odds of having vitamin A deficiency compared to those with lower AF-ALB [Odds Ratio (OR) = 2.61; CI = 1.03 – 6.58; p=0.04]. Participants with high AF-ALB also showed increased odds of having vitamin E deficiency but this was not statistically significant (OR = 2.4; CI = 0.96–6.05; p = 0.06). Conversely, those with higher AFM1 values had a statistically nonsignificant reduced odds of having vitamin A deficiency (OR = 0.31; CI = 1.15–0.09; p=0.05) and statistically significant reduced odds of having vitamin E deficiency (OR = 0.31; CI = 0.10 – 0.97; p = 0.04). Participants with high AF-ALB or high AFM1 (≥ 437.95 pg/dL creatinine) were almost 6 times more likely to be hepatitis B virus surface antigen (HBsAg)- positive (OR = 5.88; CI = 1.71–20.14; p = 0.005) and (OR = 5.84; CI = 1.15–29.54; p = 0.03) respectively. Conclusions These data indicate that aflatoxin may modify plasma micronutrient status. Thus, preventing aflatoxin exposure may greatly reduce vitamins A and E deficiencies. PMID:21792816

  19. Aflatoxin M1 Concentration in Various Dairy Products: Evidence for Biologically Reduced Amount of AFM1 in Yoghurt

    PubMed Central

    RAHIMIRAD, Amir; MAALEKINEJAD, Hassan; OSTADI, Araz; YEGANEH, Samal; FAHIMI, Samira

    2014-01-01

    Abstract Background Aflatoxin M1 (AFM1), a carcinogenic substance is found in milk and dairy products. The effect of season and type of dairy products on AFMi level in northern Iran was investigated in this study. Methods Three hundred samples (each season 75 samples) including raw and pasteurized milk, yoghurt, cheese, and cream samples were collected from three distinct milk producing farms. The samples were subjected to chemical and solid phase extractions and were analyzed by using HPLC technique. Recovery percentages, limit of detection and limit of quantification values were determined. Results Seventy percent and 98% were the minimum and maximum recoveries for cheese and raw milk, respectively and 0.021 and 0.063 ppb were the limit of detection and limit of quantification values for AFM1. We found that in autumn and winter the highest level (0.121 ppb) of AFM1 in cheese and cream samples and failed to detect any AFM1 in spring samples. Interestingly, our data showed that the yoghurt samples had the lowest level of AFM1 in all seasons. Conclusion There are significant differences between the AFM1 levels in dairy products in various seasons and also various types of products, suggesting spring and summer yoghurt samples as the safest products from AFM1 level point of view. PMID:25927044

  20. Dietary intake of aflatoxins in the adult Malaysian population - an assessment of risk.

    PubMed

    Chin, C K; Abdullah, A; Sugita-Konishi, Y

    2012-01-01

    Exposure to aflatoxins in the adult Malaysian diet was estimated by analysing aflatoxins in 236 food composites prepared as "ready for consumption". Dietary exposure to aflatoxin B1 (AFB1) ranged from 24.3 to 34.00 ng/kg b.w./day (lower to upper bound), with peanuts being the main contributor. Estimated liver cancer risk from this exposure was 0.61-0.85 cancers/100,000 population/year, contributing 12.4%-17.3% of the liver cancer cases. Excluding AFB1 occurrence data higher than 15 µg/kg reduced exposure by 65%-91% to 2.27-11.99 ng/kg b.w./day, reducing the cancer risk to 0.06-0.30 cancers/100,000 population/year (contributing 1.2%-6.1% liver cancer cases). Reducing further the ML of AFB1 from 15 to 5 µg/kg yielded 3%-7% greater drop in the exposure to 0.47-10.26 ng/kg b.w./day with an estimated risk of 0.01-0.26 cancers/100,000 population/year (0.2%-5.1% liver cancer cases attributed to dietary AFB1). These findings indicate that current MLs are adequate in protecting Malaysians' health.

  1. Reduced foodborne toxin exposure is a benefit of improving dietary diversity.

    PubMed

    Wu, Felicia; Mitchell, Nicole J; Male, Denis; Kensler, Thomas W

    2014-10-01

    Naturally occurring foodborne toxins are common in subsistence diets of low-income human populations worldwide. Often, these populations rely on one or two staple foods for the bulk of their calories, making them more susceptible to chronic intake of certain toxins. Exposure to common foodborne toxins is associated with diverse conditions such as cancer, immunotoxicity, growth impairment, and neurological deficits. Interventions focused solely on reducing toxin levels have proven difficult to sustain. Using case studies of two foodborne toxins, aflatoxin and cassava cyanide, this article addresses the heightened risk of particular diseases from eating monotonous diets based in maize, groundnuts, and cassava: common in sub-Saharan Africa and parts of Asia. We also discuss the potential role of increased dietary diversity in counteracting these diseases. Increased dietary diversity can reduce consumption of toxins and increase intake of nutrients that could counteract the toxicity of such chemicals. In Qidong, China, a population that previously consumed a monotonous maize-based diet and increased dietary diversity since the 1980s has experienced a dramatic reduction in liver cancer mortalities. That liver cancer decreased as dietary diversity increased is the catalyst for the hypothesis that dietary diversity could have a direct impact on reducing health effects of foodborne toxins. Future research, agricultural development, and food policy reforms should take into consideration the multifaceted benefits associated with improved dietary diversity. Collaborations between toxicologists, nutritionists, and policymakers are important to development of sustainable interventions to reduce foodborne toxin exposure and promote health through increased dietary diversity. © The Author 2014. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  2. Aflatoxin, hepatitis and worldwide liver cancer risks.

    PubMed

    Henry, Sara H; Bosch, F Xavier; Bowers, J C

    2002-01-01

    Aflatoxins are among the most potent mutagenic and carcinogenic substances known. Differential potency of aflatoxin among species can be partially attributed to differences in metabolism; however, current information on competing aspects of metabolic activation and detoxification of aflatoxin in various species does not identify an adequate animal model for humans. Risk of liver cancer is influenced by a number of factors, most notably carriage of hepatitis B virus as determined by the presence in serum of the hepatitis B surface antigen (HBsAg+ or HBsAg-). About 50 to 100% of liver cancer cases are estimated to be associated with persistent infection of hepatitis B (or C) virus. The potency of aflatoxin in HBsAg+ individuals is substantially higher (about a factor of 30) than the potency in HBsAg- individuals. Thus, reduction of the intake of aflatoxins in populations with a high prevalence of HBsAg+ individuals will have greater impact on reducing liver cancer rates than reductions in populations with a low prevalence of HbsAg+ individuals. The present analysis suggests that vaccination against hepatitis B (or protection against hepatits C), which reduces prevalence of carriers, would reduce the potency of the aflatoxins in vaccinated populations and reduce liver cancer risk.

  3. 46 CFR 197.545 - Program to reduce personal exposure.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Program to reduce personal exposure. 197.545 Section 197.545 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE OCCUPATIONAL SAFETY AND HEALTH STANDARDS GENERAL PROVISIONS Benzene § 197.545 Program to reduce personal exposure. (a)...

  4. 46 CFR 197.545 - Program to reduce personal exposure.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Program to reduce personal exposure. 197.545 Section 197.545 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE OCCUPATIONAL SAFETY AND HEALTH STANDARDS GENERAL PROVISIONS Benzene § 197.545 Program to reduce personal exposure. (a)...

  5. 46 CFR 197.545 - Program to reduce personal exposure.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Program to reduce personal exposure. 197.545 Section 197.545 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE OCCUPATIONAL SAFETY AND HEALTH STANDARDS GENERAL PROVISIONS Benzene § 197.545 Program to reduce personal exposure. (a)...

  6. 46 CFR 197.545 - Program to reduce personal exposure.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Program to reduce personal exposure. 197.545 Section 197.545 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE OCCUPATIONAL SAFETY AND HEALTH STANDARDS GENERAL PROVISIONS Benzene § 197.545 Program to reduce personal exposure. (a)...

  7. 46 CFR 197.545 - Program to reduce personal exposure.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Program to reduce personal exposure. 197.545 Section 197.545 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE OCCUPATIONAL SAFETY AND HEALTH STANDARDS GENERAL PROVISIONS Benzene § 197.545 Program to reduce personal exposure. (a)...

  8. Aflatoxins: characteristics and impact on human health.

    PubMed

    Kowalska, Anna; Walkiewicz, Katarzyna; Kozieł, Paweł; Muc-Wierzgoń, Małgorzata

    2017-05-05

    Some molds commonly occurring in the natural environment produce mycotoxins in the process of secondary metabolism. Aspergillus flavus and A. parasiticus are species of molds, which are responsible for the production of aflatoxins and are crucial in the pathogenesis of human diseases. Aspergillus species present in decaying plants, the soil and their spores are transferred via air currents and insects to crops and food storages. Aflatoxins B1, B2, G1, G2, M1 and M2 are the most common derivatives of aflatoxins. Ingestion of contaminated food is the main source of exposure to aflatoxins, which adversely affect the health of both humans and animals. The compounds can cause acute or chronic toxic effects of a teratogenic, mutagenic, carcinogenic, immunotoxic or hepatotoxic character. Molecular aflatoxins affect DNA mutations, postranslation peptids chains modification, proteins and nucleic acids methylation and the formation of free radicals. Due to aflatoxins carcinogenic features and frequent occurrence in food and forages they are routinely examinated in some groceries and agricultural products.

  9. Aflatoxins as a cause of hepatocellular carcinoma.

    PubMed

    Kew, Michael C

    2013-09-01

    Aflatoxins, metabolites of the fungi Aspergillus flavus and Aspergillus parasiticus, are frequent contaminants of a number of staple foods, particularly maize and ground nuts, in subsistence farming communities in tropical and sub-tropical climates in sub-Saharan Africa, Eastern Asia and parts of South America. Contamination of foods occurs during growth and as a result of storage in deficient or inappropriate facilities. These toxins pose serious public health hazards, including the causation of hepatocellular carcinoma by aflatoxin B1. Exposure begins in utero and is life-long. The innocuous parent molecule of the fungus is converted by members of the cytochrome p450 family into mutagenic and carcinogenic intermediates. Aflatoxin-B1 is converted into aflatoxin B1-8,9 exo-epoxide, which is in turn converted into 8,9-dihydroxy-8-(N7) guanyl-9-hydroxy aflatoxin B1 adduct. This adduct is metabolized into aflatoxin B1 formaminopyrimidine adduct. These adducts are mutagenic and carcinogenic. In addition, an arginine to serine mutation at codon 249 of the p53 tumor suppressor gene is produced, abrogating the function of the tumor suppressor gene, and contributing to hepatocarcinogenesis. Aflatoxin B1 acts synergistically with hepatitis B virus in causing hepatocellular carcinoma. A number of interactions between the two carcinogens may be responsible for this action, including integration of hepatitis B virus x gene and its consequences, as well as interference with nucleotide excision repair, activation of p21waf1/cip1, generation of DNA mutations, and altered methylation of genes. But much remains to be learnt about the precise pathogenetic mechanisms responsible for aflatoxin B1-induced hepatocellular carcinoma as well as the interaction between the toxin and hepatitis B virus in causing the tumor.

  10. Dietary exposure to aflatoxins, ochratoxin A and deoxynivalenol from a total diet study in an adult urban Lebanese population.

    PubMed

    Raad, F; Nasreddine, L; Hilan, C; Bartosik, M; Parent-Massin, D

    2014-11-01

    Exposure to mycotoxins may be associated with carcinogenic, immunosuppressant and estrogenic effects. In the Middle-East, studies investigating food contamination and dietary exposure to mycotoxins are particularly scarce. This study aims at evaluating the dietary exposure of an adult Lebanese urban population to four mycotoxins (AFB1, AFM1, OTA, DON) classified as priority food contaminants by the WHO. Dietary exposure assessment was performed by means of the total diet study approach. Average and excessive consumer exposure estimates (p95) were calculated and compared with appropriate toxicological reference values (TRVs). Average dietary exposure levels to OTA and DON represented 29.9% and 156.8% of the respective TRVs, with the p95 exposure estimates approaching or exceeding the TRVs for these mycotoxins (95.1% and 355.8%, respectively). Based on the mean dietary exposure level to AFB1, cancer risk was estimated at 0.0527-0.0545cases/100,000persons/year, while mean exposure to AFM1 was associated with a population risk of 0.0018-0.0027cases/100,000persons/year. The study's findings place Lebanon among countries that are highly exposed to mycotoxins through the diet and call for larger-scale studies aiming at providing a comprehensive assessment of the dietary exposure of the Lebanese population to mycotoxins as well as to other food contaminants. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  11. Food Safety Legislation Regarding Of Aflatoxins Contamination

    NASA Astrophysics Data System (ADS)

    Ketney, Otto

    2015-09-01

    The main objective of the European Union (EU) is to reduce certain contaminants in foodstuffs to acceptable levels. The occurrence of aflatoxin B1 in food was considered to be one of the most important issues of global food security to protect the health of humans and animals, over 100 nations have established maximum tolerable levels for aflatoxin in food. Although EU legislation covers many aspects of food safety was not legally establish an integrated framework that could effectively combat and cover all sectors of the food chain. Monitoring and reporting levels of aflatoxins after controls are essential actions that assist to identify potential risks to human health. The review process for aflatoxin regulations is a complex activity involving many factors and stakeholders.

  12. Ear Rot, Aflatoxin Accumulation, and Fungal Biomass in Maize after Inoculation with Aspergillus flavus

    USDA-ARS?s Scientific Manuscript database

    Aflatoxin, a toxin produced by the fungus Aspergillus flavus Link:Fries, occurs naturally in maize (Zea mays L.). Aflatoxin is a potent human carcinogen and is toxic to livestock, pets, and wildlife. When contaminated with aflatoxin, the value of maize grain is markedly reduced. Eight germplasm l...

  13. Non-aflatoxigenic Aspergillus flavus to prevent aflatoxin contamination in crops: advantages and limitations

    USDA-ARS?s Scientific Manuscript database

    Aspergillus flavus is a diverse assemblage of strains that include aflatoxin-producing and non-toxigenic strains with cosmopolitan distribution. The most promising strategy currently being used to reduce preharvest contamination of crops with aflatoxin is to introduce non-aflatoxin (biocontrol) A. f...

  14. Phlomis mauritanica extracts reduce the xanthine oxidase activity, scavenge the superoxide anions, and inhibit the aflatoxin B1-, sodium azide-, and 4-nitrophenyldiamine-induced mutagenicity in bacteria.

    PubMed

    Limem, Ilef; Bouhlel, Ines; Bouchemi, Meriem; Kilani, Soumaya; Boubaker, Jihed; Ben-Sghaier, Mohamed; Skandrani, Ines; Behouri, Wissem; Neffati, Aicha; Ghedira, Kamel; Chekir-Ghedira, Leila

    2010-06-01

    Four extracts were prepared from the leaves of Phlomis mauritanica: lyophilized infusion, total oligomer flavonoids, methanol, and ethyl acetate extracts. The antimutagenic properties of these extracts were investigated by assessing the inhibition of the mutagenic effects of direct-acting mutagens such as sodium azide and 4-nitrophenylenediamine and indirect-acting mutagens like aflatoxin B1 (AFB1) using the Ames assay. The four extracts prepared from P. mauritanica strongly inhibit the mutagenicity induced by AFB1 in both Salmonella typhimurium TA 100 and TA 98 assay systems. Lyophilized infusion and methanol extracts at the dose of 250 microg per plate reduced AFB1 mutagenicity by 93% and 91%, respectively, in S. typhymurium strain TA 100. We examined also the antioxidant effect of these extracts by the enzymatic xanthine/xanthine oxidase assay. Result indicated that total oligomer flavonoids and ethyl acetate and methanol extracts were potent inhibitors of xanthine oxidase activity. In contrast, lyophilized infusion, total oligomer flavonoids, and methanol extracts exhibited a high degree of superoxide anion scavenging. Our findings emphasize the potential of P. mauritanica extracts to prevent mutations and oxidant effects. Furthermore, the results presented here could be an additional argument to support the use of this species as a medicinal and dietary plant.

  15. Simple methods to reduce patient exposure during scoliosis radiography

    SciTech Connect

    Butler, P.F.; Thomas, A.W.; Thompson, W.E.; Wollerton, M.A.; Rachlin, J.A.

    1986-05-01

    Radiation exposure to the breasts of adolescent females can be reduced significantly through the use of one or all of the following methods: fast, rare-earth screen-film combinations; specially designed compensating filters; and breast shielding. The importance of exposure reduction during scoliosis radiography as well as further details on the above described methods are discussed. In addition, the early results of a Center for Devices and Radiological Health study, which recorded exposure and technique data for scoliosis radiography, is presented.

  16. Inhibition of Aflatoxin Production by Surfactants

    PubMed Central

    Rodriguez, Susan B.; Mahoney, Noreen E.

    1994-01-01

    The effect of 12 surfactants on aflatoxin production, growth, and conidial germination by the fungus Aspergillus flavus is reported. Five nonionic surfactants, Triton X-100, Tergitol NP-7, Tergitol NP-10, polyoxyethylene (POE) 10 lauryl ether, and Latron AG-98, reduced aflatoxin production by 96 to 99% at 1% (wt/vol). Colony growth was restricted by the five nonionic surfactants at this concentration. Aflatoxin production was inhibited 31 to 53% by lower concentrations of Triton X-100 (0.001 to 0.0001%) at which colony growth was not affected. Triton X-301, a POE-derived anionic surfactant, had an effect on colony growth and aflatoxin production similar to that of the five POE-derived nonionic surfactants. Sodium dodecyl sulfate (SDS), an anionic surfactant, and dodecyltrimethylammonium bromide, a cationic surfactant, suppressed conidial germination at 1% (wt/vol). SDS had no effect on aflatoxin production or colony growth at 0.001%. The degree of aflatoxin inhibition by a surfactant appears to be a function of the length of the hydrophobic and hydrophilic chains of POE-derived surfactants. Images PMID:16349144

  17. Immunoassay procedures to detect exposure to aflatoxin B1 and benzo(a)pyrene in animals and man at the DNA level.

    PubMed

    Garner, R C; Dvorackova, I; Tursi, F

    1988-01-01

    Immunological methods were used to examine human liver for the presence of aflatoxin-DNA adducts and human lung for benzo(a)pyrene diol-epoxide DNA (BPDE-DNA) adducts. Eight liver samples obtained from Czechoslovakian patients with primary hepatocellular carcinoma were studied, seven of which had detectable anti-aflatoxin inhibitory material. Values ranged between 0.63 and 3.51 picomoles aflatoxin per mg DNA. In a separate, independent study performed in another laboratory the one sample with no aflatoxin bound to DNA also had no free aflatoxin present in the liver. In the case of the human lung DNA samples, 12 samples were examined, the samples having been removed during thoracic surgery, and five had detectable anti-BPDE-DNA antibody activity. The positive samples were all from smokers and had inhibitory values ranging from 4 to 12 femtomoles per mg DNA. Samples were prepared by immunoconcentration prior to analysis. These preliminary results support the view that immunological methods can be used to examine human tissue DNA for carcinogen adducts.

  18. Improved intensifying screen reduces X-ray exposure

    NASA Technical Reports Server (NTRS)

    Buchanan, R. A.

    1972-01-01

    X-ray intensifying screen may make possible radiographic procedures where detection speed and X-ray tube power have been the limiting factors. Device will reduce total population exposure to harmful radiation in the United States.

  19. Characterization of a murine p53ser246 mutant equivalent to the human p53ser249 associated with hepatocellular carcinoma and aflatoxin exposure.

    PubMed

    Ghebranious, N; Knoll, B J; Wu, H; Lozano, G; Sell, S

    1995-06-01

    A mutation in the tumor suppressor p53 gene resulting in an Arg-->Ser substitution in position 249 is found frequently in human hepatocellular carcinomas associated with hepatitis B infection and with aflatoxin exposure. To determine the significance of this mutation in an in vivo experimental model using transgenic mice, we introduced a two-nucleotide change in the mouse p53 gene at amino-acid position 246, which is equivalent to position 249 in human p53, by the recombinant polymerase chain reaction mismatched primer method. This p53 mutation resulted in the same change, an Arg-->Ser substitution, as in the human p53 gene at position 249. We now report that the protein product of this mutant mouse p53ser246 had properties similar to those of the wild-type protein when tested by binding to (i) monoclonal antibodies PAb246 and PAb240, ii) simian virus 40 large T antigen, and (iii) heat-shock protein. However, it had mutant-type transforming properties when tested for colony formation with an osteosarcoma cell line. It was not active, as is wild-type p53, in transcription activation of the muscle creatine kinase promoter. These properties are the same as those found in the p53trp248 product of the p53 mutation associated with the Li-Fraumeni syndrome. Although less is known about the human p53ser249 product associated with hepatocellular carcinoma, the mutant murine p53ser246 protein shares the known properties of the human gene product.

  20. Aflatoxin M1 in processed milk: Occurrence and seasonal variation with an emphasis on risk assessment of human exposure in Serbia

    NASA Astrophysics Data System (ADS)

    Milićević, D.; Spirić, D.; Janković, S.; Velebit, B.; Radičević, T.; Petrović, Z.; Stefanović, S.

    2017-09-01

    The objectives of this study were to assess aflatoxin M1 (AFM1) contamination in processed milk and dairy products, and to estimate the mean daily exposure of the adult Serbian population to AFM1 due to milk consumption. A total of 1734 samples, comprising heat treated cow’s milk (n=1233), infant formulae (n=349), milk powder (n=94) and dairy drink (n=58), were analyzed for AFM1 presence using an Enzyme-Linked Immunosorbent Assay (ELISA) commercial kit. Samples were collected from different regions of Serbia during four seasons each year during 2015 and 2016. The incidences of AFM1 contamination were 77.8% with a mean level of 0.027±0.03 μg/L (range of <0.005-0.278 μg/L) in samples collected in 2015, and 98.4% with a mean level of 0.039±0.02 μg/L (range of <0.005-0.28 μg/L) in samples collected in 2016. The highest AFM1 levels were measured in October 2015 (0.278 μg/L) and September 2016 (0.279 μg/L). Based on EU regulation, 214 (17.3%) milk samples exceeded the maximum residue limit (0.05 μg/L). The estimated daily intake (EDI) of AFM1 during different seasons of year for males and females was in the range of 0.022-0.330 (mean 0.20) ng/kg/bw/day and 0.022-0.30 (mean 0.18) ng/kg/bw/day, respectively. The calculated EDI indicate a public health concern due to the carcinogenic effects of AFM1.

  1. Aflatoxin Accumulation in BT and non-BT Maize Testcrosses

    USDA-ARS?s Scientific Manuscript database

    The accumulation of aflatoxin, which is produced by the fungus, Aspergillus flavus Link: Fries, in maize is a chronic problem in the southeastern United States. Its presence in grain greatly reduces its value and marketability. Aflatoxin accumulation is frequently associated with high temperatures...

  2. Chronic lead exposure reduces junctional resistance at an electrical synapse.

    PubMed

    Audesirk, G; Audesirk, T

    1984-01-01

    Both acute and chronic lead exposure have been found to inhibit transmission at chemical synapses, possibly by interfering with inward calcium current. We have found that chronic lead exposure slightly reduces input resistance and greatly reduces the junctional resistance between two strongly electrically coupled neurons in the pond snail Lymnaea stagnalis. The net effect is to increase the strength of electrical coupling. A reduction in gap junctional resistance would also be expected to increase the flow of small molecules between cells. However, Lucifer Yellow injections did not reveal dye-coupling between the cells. Lead exposure also increases the capacitance of the neurons.

  3. Aflatoxin variability in pistachios.

    PubMed Central

    Mahoney, N E; Rodriguez, S B

    1996-01-01

    Pistachio fruit components, including hulls (mesocarps and epicarps), seed coats (testas), and kernels (seeds), all contribute to variable aflatoxin content in pistachios. Fresh pistachio kernels were individually inoculated with Aspergillus flavus and incubated 7 or 10 days. Hulled, shelled kernels were either left intact or wounded prior to inoculation. Wounded kernels, with or without the seed coat, were readily colonized by A. flavus and after 10 days of incubation contained 37 times more aflatoxin than similarly treated unwounded kernels. The aflatoxin levels in the individual wounded pistachios were highly variable. Neither fungal colonization nor aflatoxin was detected in intact kernels without seed coats. Intact kernels with seed coats had limited fungal colonization and low aflatoxin concentrations compared with their wounded counterparts. Despite substantial fungal colonization of wounded hulls, aflatoxin was not detected in hulls. Aflatoxin levels were significantly lower in wounded kernels with hulls than in kernels of hulled pistachios. Both the seed coat and a water-soluble extract of hulls suppressed aflatoxin production by A. flavus. PMID:8919781

  4. Effect of supplementation of fermented milk drink containing probiotic Lactobacillus casei Shirota on the concentrations of aflatoxin biomarkers among employees of Universiti Putra Malaysia: a randomised, double-blind, cross-over, placebo-controlled study.

    PubMed

    Mohd Redzwan, Sabran; Abd Mutalib, Mohd Sokhini; Wang, Jia-Sheng; Ahmad, Zuraini; Kang, Min-Su; Abdul Rahman, Nurul 'Aqilah; Nikbakht Nasrabadi, Elham; Jamaluddin, Rosita

    2016-01-14

    Human exposure to aflatoxin is through the diet, and probiotics are able to bind aflatoxin and prevent its absorption in the small intestine. This study aimed to determine the effectiveness of a fermented milk drink containing Lactobacillus casei Shirota (LcS) (probiotic drink) to prevent aflatoxin absorption and reduce serum aflatoxin B1-lysine adduct (AFB1-lys) and urinary aflatoxin M1 concentrations. The present study was a randomised, double-blind, cross-over, placebo-controlled study with two 4-week intervention phases. In all, seventy-one subjects recruited from the screening stage were divided into two groups--the Yellow group and the Blue group. In the 1st phase, one group received probiotic drinks twice a day and the other group received placebo drinks. Blood and urine samples were collected at baseline, 2nd and 4th week of the intervention. After a 2-week wash-out period, the treatments were switched between the groups, and blood and urine samples were collected at the 6th, 8th and 10th week (2nd phase) of the intervention. No significant differences in aflatoxin biomarker concentrations were observed during the intervention. A within-group analysis was further carried out. Aflatoxin biomarker concentrations were not significantly different in the Yellow group. Nevertheless, ANOVA for repeated measurements indicated that AFB1-lys concentrations were significantly different (P=0·035) with the probiotic intervention in the Blue group. The 2nd week AFB1-lys concentrations (5·14 (SD 2·15) pg/mg albumin (ALB)) were significantly reduced (P=0·048) compared with the baseline (6·24 (SD 3·42) pg/mg ALB). Besides, the 4th week AFB1-lys concentrations were significantly lower (P<0·05) with probiotic supplementation than with the placebo. Based on these findings, a longer intervention study is warranted to investigate the effects of continuous LcS consumption to prevent dietary aflatoxin exposure.

  5. Deletion of the Aspergillus flavus orthologue of A. nidulans fluG reduces conidiation and promotes production of sclerotia but does not abolish aflatoxin biosynthesis

    USDA-ARS?s Scientific Manuscript database

    Aspergillus flavus fluG deletion strains showed decreased conidiation but had elevated sclerotial production. These developmental changes were not remediated by co-culturing with fluG-positive strains. The fluG mutant still retained its aflatoxin-producing ability. The A. flavus fluG gene functions ...

  6. Exposure to violence reduces empathetic responses to other's pain.

    PubMed

    Guo, Xiuyan; Zheng, Li; Wang, Hongyi; Zhu, Lei; Li, Jianqi; Wang, Qianfeng; Dienes, Zoltan; Yang, Zhiliang

    2013-07-01

    Past researches showed that empathy for pain not only triggers a resonance mechanism between other and self, but also is modulated by contextual factors. Using functional magnetic resonance imaging, the present study demonstrated that short-term media violence exposure reduced both pain ratings and also the activation of anterior insula and anterior mid-cingulate cortex to other's pain. Thus, violence exposure modulated empathic responses to other's pain based on a physiological desensitization.

  7. Inactivation of aflatoxin B1 by using the synergistic effect of hydrogen peroxide and gamma radiation

    SciTech Connect

    Patel, U.D.; Govindarajan, P.; Dave, P.J. )

    1989-02-01

    Inactivation of aflatoxin B1 was studied by using gamma radiation and hydrogen peroxide. A 100-krad dose of gamma radiation was sufficient to inactivate 50 micrograms of aflatoxin B1 in the presence of 5% hydrogen peroxide, and 400 krad was required for total degradation of 100 micrograms of aflatoxin in the same system. Degradation of aflatoxin B1 was confirmed by high-pressure liquid chromatographic and thin-layer chromatographic analysis. Ames microsomal mutagenicity test showed loss of aflatoxin activity. This method of detoxification also reduces the toxin levels effectively in artificially contaminated groundnuts.

  8. Protecting children: reducing their environmental tobacco smoke exposure.

    PubMed

    Klerman, Lorraine

    2004-04-01

    The present review examines the current status of efforts to reduce environmental tobacco smoke exposure (ETS) among infants and young children. Estimates of the number of children exposed vary, but it is probably over 20 million or about 35% of all U.S. children. Healthy People 2010 sets as an objective the reduction, to 10%, of the proportion of children regularly exposed to tobacco smoke at home. Children with ETS exposure are at higher risk for upper respiratory illnesses, asthma, otitis media, and sudden infant death syndrome. Eight experimental or quasi-experimental studies of attempts to reduce children' ETS exposure with sample sizes of greater than 100 were conducted in the United States and published between 1990 and 2003. Most of these studies showed a significant impact on maternal smoking and on the number of cigarettes smoked in the home, although intervention-control differences were relatively small. Despite support from professional organizations and federal government groups, many pediatricians and family physicians do not routinely engage in intensive efforts to reduce children's ETS exposure. Training in techniques for reducing tobacco dependence should be included in professional education programs. Public and private insurance should reimburse providers for efforts in this area. An overall strategy for reducing children's ETS exposure should combine individual counseling and education in offices, clinics, and homes with community education and regulatory and economic policies (i.e., smoking bans and excise taxes). Additional funding is needed for studies of provider knowledge, attitudes, and practices; of the effectiveness of various communication strategies; and of office- and community-based strategies to reduce ETS exposure.

  9. Efforts to reduce exposure at Japanese PWRs: CVCS improvement

    SciTech Connect

    Terada, Ryosuke

    1995-03-01

    Many reports have been focused on the reduction of radiation sources and related occupational exposures. The radiation sources mainly consist of corrosion products. Radiation dose rate is determined by the amount of the activated corrosion products on the surface of the primary loop components of Pressurized Water Reactor (PWR) plants. Therefore, reducing the amount of the corrosion product will contribute to the reduction of occupational exposures. In order to reduce the corrosion products, Chemical and Volume Control System (CVCS) has been improved in Japanese PWRs as follows: (a) Cation Bed Demineralizer Flowrate Control; (b) Hydrogen Peroxide Injection System; (c) Purification Flowrate During Plant Shutdown; (d) Fine Mesh Filters Upstream of Mixed Bed Demineralizers.

  10. Trait and state anxiety reduce the mere exposure effect.

    PubMed

    Ladd, Sandra L; Gabrieli, John D E

    2015-01-01

    The mere exposure effect refers to an affective preference elicited by exposure to previously unfamiliar items. Although it is a well-established finding, its mechanism remains uncertain, with some positing that it reflects affective processes and others positing that it reflects perceptual or motor fluency with repeated items. Here we examined whether individual differences in trait and state anxiety, which have been associated with the experience of emotion, influence the mere exposure effect. Participants' trait (Study 1) and state (Study 2) anxiety were characterized with the State-Trait Anxiety Inventory. Greater trait and state anxiety correlated with greater negative affect and lesser positive affect. In both experiments, greater anxiety was associated with a reduced mere exposure effect. Measures of fluency (response times at study and test) were unrelated to the mere exposure effect. These findings support the role of affective processes in the mere exposure effect, and offer a new insight into the nature of anxiety such that anxiety is associated with a reduced experience of positive affect typically associated with familiarity.

  11. Determinants of aflatoxin levels in Ghanaians: sociodemographic factors, knowledge of aflatoxin and food handling and consumption practices.

    PubMed

    Jolly, Pauline; Jiang, Yi; Ellis, William; Awuah, Richard; Nnedu, Obinna; Phillips, Timothy; Wang, Jia-Sheng; Afriyie-Gyawu, Evans; Tang, Lili; Person, Sharina; Williams, Jonathan; Jolly, Curtis

    2006-07-01

    Aflatoxins are among the most potent of carcinogens found in staple foods such as groundnuts, maize and other oil seeds. This study was conducted to measure the levels of aflatoxin B(1) (AFB(1)) albumin adducts in blood and aflatoxin M(1) (AFM(1)) metabolite in urine of people in a heavy peanut and maize consuming region of Ghana and to examine the association between aflatoxin levels and several socio-demographic factors and food handling and consumption practices. A cross-sectional study was conducted in four villages in the Ejura Sekyedumase district of Ghana. A socio-demographic survey was administered to 162 participants. Blood samples were collected from 140 and urine samples from 91 of the participants and AFB(1) albumin-adduct levels in blood and AFM(1) levels in urine were measured. High AFB(1) albumin-adduct levels were found in the plasma (mean+/-SD=0.89+/-0.46pmol/mg albumin; range=0.12-3.00pmol/mg; median=0.80pmol/mg) and high AFM(1) levels in the urine (mean+/-SD=1,800.14+/-2602.01pg/mg creatinine; range=non-detectable to 11,562.36pg/mg; median=472.67pg/mg) of most of the participants. There was a statistically significant correlation (r=0.35; p=0.007) between AFB(1)-albumin adduct levels in plasma and AFM(1) levels in urine. Several socio-demographic factors, namely, educational level, ethnic group, the village in which participants lived, number of individuals in the household, and number of children in the household attending secondary school, were found to be significantly associated with AFB(1) albumin-adduct levels by bivariate analysis. By multivariate analyses, ethnic group (p=0.04), the village in which participants live (p=0.02), and the number of individuals in the household (p=0.01), were significant predictors of high AFB(1) albumin-adducts. These findings indicate strongly that there is need for specifically targeted post-harvest and food handling and preparation interventions designed to reduce aflatoxin exposure among the different

  12. Production of aflatoxin byAspergillus parasiticus and its control.

    PubMed

    Emara, H A

    1997-03-01

    The aim of the present work was to investigate the production of aflatoxin byAspergillus parasiticus and to find out the possible ways to control it. Of 40 food samples collected from Abha region, Saudi Arabia, only 25% were contaminated with aflatoxins. Oil-rich commodities had the highly contaminated commodities by fungi and aflatoxins while spices were free from aflatoxins.Bacillus megatertum andB cereus were suitable for microbiological assay of aflatoxins. Czapek's-Dox medium was found a suitable medium for isolation of fungi from food samples. The optimal pH for the growth ofA. parasiticus and its productivity of aflatoxin B1 was found at 6.0, while the best incubation conditions were found at 30°C for 10 days. D-glucose was the best carbon source for fungal growth, as well as aflatoxin production. Corn steep liquor, yeast extract and peptone were the best nitrogen sources for both fungal growth and toxin production (NH4)2HPO4 (1.55 gL(-1)) and NaNO2 (1.6 gL(-1)) reduced fungal growth and toxin production with 37.7% and 85%, respectively. Of ten amino acids tested, asparagine was the best for aflatoxin B1 production. Zn(2+) and Co(2+) supported significantly both fungal growth, as well as, aflatoxin B1 production at the different tested concentrations. Zn(2+) was effective when added toA. parasiticus growth medium at the first two days of the culture age. The other tested metal ions expressed variable effects depending on the type of ion and its concentration. Water activity (aw) was an important factor controlling the growth ofA. parasiticus and toxin production. The minimum aw for the fungal growth was 0.8 on both coffee beans and rice grains, while aw of 0.70 caused complete inhibition for the growth and aflatoxin B1 production. H2O2 is a potent inhibitor for growth ofA. parasiticus and its productivity of toxins. NaHCO3 and C6H5COONa converted aflatoxin B1 to water-soluble form which returned to aflatoxin B1 by acidity. Black pepper, ciliated heath

  13. Reducing chemical exposures at home: opportunities for action.

    PubMed

    Zota, Ami R; Singla, Veena; Adamkiewicz, Gary; Mitro, Susanna D; Dodson, Robin E

    2017-07-29

    Indoor environments can influence human environmental chemical exposures and, ultimately, public health. Furniture, electronics, personal care and cleaning products, floor coverings and other consumer products contain chemicals that can end up in the indoor air and settled dust. Consumer product chemicals such as phthalates, phenols, flame retardants and per- and polyfluorinated alkyl substances are widely detected in the US general population, including vulnerable populations, and are associated with adverse health effects such as reproductive and endocrine toxicity. We discuss the implications of our recent meta-analysis describing the patterns of chemical exposures and the ubiquity of multiple chemicals in indoor environments. To reduce the likelihood of exposures to these toxic chemicals, we then discuss approaches for exposure mitigation: targeting individual behaviour change, household maintenance and purchasing decisions, consumer advocacy and corporate responsibility in consumer markets, and regulatory action via state/federal policies. There is a need to further develop evidence-based strategies for chemical exposure reduction in each of these areas, given the multi-factorial nature of the problem. Further identifying those at greatest risk; understanding the individual, household and community factors that influence indoor chemical exposures; and developing options for mitigation may substantially improve individuals' exposures and health. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  14. The potential effects of Zataria multiflora Boiss essential oil on growth, aflatoxin production and transcription of aflatoxin biosynthesis pathway genes of toxigenic Aspergillus parasiticus.

    PubMed

    Yahyaraeyat, R; Khosravi, A R; Shahbazzadeh, D; Khalaj, V

    2013-01-01

    This study aims at evaluating the effects of Zataria multiflora (Z. multiflora) essential oil (EO) on growth, aflatoxin production and transcription of aflatoxin biosynthesis pathway genes. Total RNAs of Aspergillus parasiticus (A.parasiticus) ATCC56775 grown in yeast extract sucrose (YES) broth medium treated with Z. multiflora EO were subjected to reverse transcription- polymerase chain reaction (RT-PCR). Specific primers of nor-1, ver-1, omt-A and aflR genes were used. In parallel mycelial dry weight of samples were measured and all the media were assayed by high-pressure liquid chromatography (HPLC) for aflatoxinB1 (AFB1), aflatoxinB2 (AFB2), aflatoxinG1 (AFG1), aflatoxinG2 (AFG2) and aflatoxin total (AFTotal) production. The results showed that mycelial dry weight and aflatoxin production reduce in the presence of Z. multiflora EO (100 ppm) on day 5 of growth. It was found that the expression of nor-1, ver-1, omt-A and aflR genes was correlated with the ability of fungus to produce aflatoxins on day 5 in YES medium. RT-PCR showed that in the presence of Z.multiflora EO (100 ppm) nor-1, ver-1 and omtA genes expression was reduced. It seems that toxin production inhibitory effects of Z. multiflora EO on day 5 may be at the transcription level and this herb may cause reduction in aflatoxin biosynthesis pathway genes activity.

  15. Reducing waste generation and radiation exposure by analytical method modification

    SciTech Connect

    Ekechukwu, A.A.

    1996-10-01

    The primary goal of an analytical support laboratory has traditionally been to provide accurate data in a timely and cost effective fashion. Added to this goal is now the need to provide the same high quality data while generating as little waste as possible. At the Savannah River Technology Center (SRTC), we have modified and reengineered several methods to decrease generated waste and hence reduce radiation exposure. These method changes involved improving detection limits (which decreased the amount of sample required for analysis), decreasing reaction and analysis time, decreasing the size of experimental set-ups, recycling spent solvent and reagents, and replacing some methods. These changes had the additional benefits of reducing employee radiation exposure and exposure to hazardous chemicals. In all cases, the precision, accuracy, and detection limits were equal to or better than the replaced method. Most of the changes required little or no expenditure of funds. This paper describes these changes and discusses some of their applications.

  16. CHRONIC DEVELOPMENTAL LEAD EXPOSURE REDUCES NEUROGENESIS IN ADULT HIPPOCAMPUS.

    EPA Science Inventory

    CHRONIC DEVELOPMENTAL LEAD EXPOSURE REDUCES NEUROGENESIS IN ADULT HIPPOCAMPUS. ME Gilbert1, ME Kelly2, S. Salant3, T Shafer1, J Goodman3 1Neurotoxicology Div, US EPA, RTP, NC, 27711, 2Children's Hospital, Philadelphia, PA, 19104, 3Helen Hayes Hospital, Haverstraw, NY, 10993.
    ...

  17. CHRONIC DEVELOPMENTAL LEAD EXPOSURE REDUCES NEUROGENESIS IN ADULT HIPPOCAMPUS.

    EPA Science Inventory

    CHRONIC DEVELOPMENTAL LEAD EXPOSURE REDUCES NEUROGENESIS IN ADULT HIPPOCAMPUS. ME Gilbert1, ME Kelly2, S. Salant3, T Shafer1, J Goodman3 1Neurotoxicology Div, US EPA, RTP, NC, 27711, 2Children's Hospital, Philadelphia, PA, 19104, 3Helen Hayes Hospital, Haverstraw, NY, 10993.
    ...

  18. Aflatoxin B1 and M1 contamination of animal feeds and milk from urban centers in Kenya.

    PubMed

    Kang'ethe, Erastus K; Lang'a, K A

    2009-12-01

    Aflatoxin M1 (AFM1) is the principal hydroxylated AFB1 metabolite present in milk of cows fed with a diet contaminated with AFB1and excreted within 12 hours of administration of contaminated feeds. This study was initiated to assess the knowledge and practices of urban dairy farmers and feed millers about aflatoxin in feeds and milk, determine the prevalence and quantify the levels of AFB1 and AFM1 in animal feeds and milk respectively from urban environs in Kenya. This work was carried out in the Department of Public Health Pharmacology and Toxicology, University of Nairobi, Kenya, between February 2006 and March 2007. A total of 830 animal feed and 613 milk samples from four urban centers were analyzed for aflatoxin B1 and M1 respectively using competitive enzyme immunoassay. Eighty six percent (353/412) of the feed samples from farmers were positive for aflatoxin B1 and 67% (235/353) of these exceeded the FAO/WHO level of 5µ gKg-1. Eighty one percent (197/243) of the feed samples from feed millers and 87% (153/175) from agrochemical shops were positive, while 58% (115/197) and 66% (92/153) of the positive samples exceeded the FAO/WHO limits respectively. Seventy two percent (315/439) of the milk from dairy farmers, 84% (71/85) from large and medium scale farmers and 99% (88/89) of the pasteurized marketed milk were positive for aflatoxin M1, and 20%, 35% an 31% of positive milk from dairy farmers, medium and large scale farmers and market outlets respectively, exceeded the WHO/FAO levels of 0.05µ g/Kg-1. Sixty seven percent of the urban smallholder dairy farmers had no knowledge that milk could be contaminated with aflatoxin M1 and neither knew how they could mitigate against this exposure. Feed millers knew about aflatoxin B1 in grains and excretion of aflatoxin M1 in milk, but were not alleviating exposure to animals. There is need to create awareness and establish routine monitoring of animal feeds and milk to reduce animal and consequently human response.

  19. Effects of Pistacia atlantica subsp. kurdica on Growth and Aflatoxin Production by Aspergillus parasiticus

    PubMed Central

    Khodavaisy, Sadegh; Rezaie, Sassan; Noorbakhsh, Fatemeh; Baghdadi, Elham; Sharifynia, Somayeh; Aala, Farzad

    2016-01-01

    Background Aflatoxins are highly toxic secondary metabolites mainly produced by Aspergillus parasiticus. This species can contaminate a wide range of agricultural commodities, including cereals, peanuts, and crops in the field. In recent years, research on medicinal herbs, such as Pistacia atlantica subsp. kurdica, have led to reduced microbial growth, and these herbs also have a particular effect on the production of aflatoxins as carcinogenic compounds. Objectives In this study, we to examine P. atlantica subsp. kurdica as a natural compound used to inhibit the growth of A. parasiticus and to act as an anti-mycotoxin. Materials and Methods In vitro antifungal susceptibility testing of P. atlantica subsp. kurdica for A. parasiticus was performed according to CLSI document M38-A2. The rate of aflatoxin production was determined using the HPLC technique after exposure to different concentrations (62.5 - 125 mg/mL) of the gum. The changes in expression levels of the aflR gene were analyzed with a quantitative real-time PCR assay. Results The results showed that P. atlantica subsp. kurdica can inhibit A. parasiticus growth at a concentration of 125 mg/mL. HPLC results revealed a significant decrease in aflatoxin production with 125 mg/mL of P. atlantica subsp. kurdica, and AFL-B1 production was entirely inhibited. Based on quantitative real-time PCR results, the rate of aflR gene expression was significantly decreased after treatment with P. atlantica subsp. kurdica. Conclusions Pistacia atlantica subsp. kurdica has anti-toxic properties in addition to an inhibitory effect on A. parasiticus growth, and is able to decrease aflatoxin production effectively in a dose-dependent manner. Therefore, this herbal extract maybe considered a potential anti-mycotoxin agent in medicine or industrial agriculture. PMID:27800127

  20. Cost-effectiveness of lowering the aflatoxin tolerance level.

    PubMed

    Dichter, C R; Weinstein, M C

    1984-06-01

    The cost-effectiveness of adopting aflatoxin tolerance levels of 15, 10 and 5 ppb for peanuts and peanut products was assessed. Estimates of the annual cost to manufacturers of monitoring and controlling peanut aflatoxin levels at the current 20-ppb action level, and estimates of the projected increase in costs of establishing lower tolerances were elicited from producers by questionnaire. Exposures to peanut products were derived from the HANES I survey and from peanut production statistics. The risk of liver cancer at each tolerance level was estimated using both epidemiological and extrapolated experimental data assuming that exposure would be reduced in direct proportion to the decrease in the tolerance. It was found that the 15-ppb tolerance would cost $60,000 per cancer death averted (range $20,000-$1,700,000) and is therefore relatively cost-effective. The marginal costs per life saved for both the 10-ppb and 5-ppb levels were found to be $1.7 million (range $0.6 million-$11.4 million) and $1.6 million (range +0.6 million-$31.1 million), respectively. Conclusions on the optimal regulatory approach should be guided by comparisons of these figures with corresponding cost-effectiveness ratios for alternative regulatory uses of national resources in the interests of public health.

  1. Aflatoxins and kwashiorkor: a study in Sudanese children.

    PubMed Central

    Hendrickse, R G; Coulter, J B; Lamplugh, S M; Macfarlane, S B; Williams, T E; Omer, M I; Suliman, G I

    1982-01-01

    Blood and urine samples from 252 Sudanese children were investigated for their aflatoxin content by high-performance liquid chromatography. The children comprised 44 with kwashiorkor, 32 with marasmic kwashiorkor, 70 with marasmus, and 106 age-matched, normally nourished controls. Aflatoxins were detected more often and at higher concentrations in sera from children with kwashiorkor than in the other malnourished and control groups. Aflatoxicol, a metabolite of aflatoxins B1 and B2, was detected in the sera of children with kwashiorkor and marasmic kwashiorkor but not in the controls and only once in a marasmic child. The difference between children with kwashiorkor or marasmic kwashiorkor and those in the control or marasmus groups was significant. Urinary aflatoxin was most often detected in children with kwashiorkor but their mean concentration was lower than in the other groups. Aflatoxicol was not detected in urine in any group. These findings suggest either that the children with kwashiorkor have a greater exposure to aflatoxins or that their ability to transport and excrete aflatoxins is impaired by the metabolic derangements associated with kwashiorkor. The presence of aflatoxicol in the sera of children with kwashiorkor but not in the others suggests a difference in metabolism between the two groups. Further studies are needed, and measurement of aflatoxins in the food eaten by these children is already underway. PMID:6811035

  2. Estimated exposure to EU regulated mycotoxins and risk characterization of aflatoxin-induced hepatic toxicity through the consumption of the toasted cereal flour called "gofio", a traditional food of the Canary Islands (Spain).

    PubMed

    Luzardo, Octavio P; Bernal-Suárez, María Del Mar; Camacho, María; Henríquez-Hernández, Luis Alberto; Boada, Luis D; Rial-Berriel, Cristian; Almeida-González, Maira; Zumbado, Manuel; Díaz-Díaz, Ricardo

    2016-07-01

    "Gofio" is a type of flour made from toasted grain, which is part of the staple food in the Canary Islands, Spain, in which the occurrence of Aflatoxins B1, B2, G1 and G2 (AFB1, AFB2, AFG1, AFG2), Fumonisins B1 and B2 (FB1 and FB2) Ochratoxin A (OTA), Deoxynivalenol (DNV) and Zearalenone (ZEA) was evaluated. 83% of the samples were contaminated with at least one mycotoxin and 69.2% of the analyzed samples showed co-occurrence of mycotoxins (range 2 to 8). All the concentrations were well below the established limits (maximum values of AFs=0.42 μg/kg; FBs=178.3 μg/kg; OTA=0.3 μg/kg; DON=92.5 μg/kg; and ZEA=9.9 μg/kg). The daily dietary exposure to total AFs was estimated to be 7.1% of the TDI. This value was almost double in children, and considering the upper-bound approach could reach 35% of the TDI. For the rest of mycotoxins, the consumers would be exposed to less than 2% of their TDIs. The risk characterization indicates that there is a potential risk in developing aflatoxin induced liver cancer due to gofio consumption in the subpopulation which is simultaneously exposed to other hepatocarcinogens, such as the hepatitis B virus. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Recirculating Air Filtration Significantly Reduces Exposure to Airborne Nanoparticles

    PubMed Central

    Pui, David Y.H.; Qi, Chaolong; Stanley, Nick; Oberdörster, Günter; Maynard, Andrew

    2008-01-01

    Background Airborne nanoparticles from vehicle emissions have been associated with adverse effects in people with pulmonary and cardiovascular disease, and toxicologic studies have shown that nanoparticles can be more hazardous than their larger-scale counterparts. Recirculating air filtration in automobiles and houses may provide a low-cost solution to reducing exposures in many cases, thus reducing possible health risks. Objectives We investigated the effectiveness of recirculating air filtration on reducing exposure to incidental and intentionally produced airborne nanoparticles under two scenarios while driving in traffic, and while generating nanomaterials using gas-phase synthesis. Methods We tested the recirculating air filtration in two commercial vehicles when driving in traffic, as well as in a nonventilation room with a nanoparticle generator, simulating a nanomaterial production facility. We also measured the time-resolved aerosol size distribution during the in-car recirculation to investigate how recirculating air filtration affects particles of different sizes. We developed a recirculation model to describe the aerosol concentration change during recirculation. Results The use of inexpensive, low-efficiency filters in recirculation systems is shown to reduce nanoparticle concentrations to below levels found in a typical office within 3 min while driving through heavy traffic, and within 20 min in a simulated nanomaterial production facility. Conclusions Development and application of this technology could lead to significant reductions in airborne nanoparticle exposure, reducing possible risks to health and providing solutions for generating nanomaterials safely. PMID:18629306

  4. Recirculating air filtration significantly reduces exposure to airborne nanoparticles.

    PubMed

    Pui, David Y H; Qi, Chaolong; Stanley, Nick; Oberdörster, Günter; Maynard, Andrew

    2008-07-01

    Airborne nanoparticles from vehicle emissions have been associated with adverse effects in people with pulmonary and cardiovascular disease, and toxicologic studies have shown that nanoparticles can be more hazardous than their larger-scale counterparts. Recirculating air filtration in automobiles and houses may provide a low-cost solution to reducing exposures in many cases, thus reducing possible health risks. We investigated the effectiveness of recirculating air filtration on reducing exposure to incidental and intentionally produced airborne nanoparticles under two scenarios: while driving in traffic, and while generating nanomaterials using gas-phase synthesis. We tested the recirculating air filtration in two commercial vehicles when driving in traffic, as well as in a nonventilation room with a nanoparticle generator, simulating a nanomaterial production facility. We also measured the time-resolved aerosol size distribution during the in-car recirculation to investigate how recirculating air filtration affects particles of different sizes. We developed a recirculation model to describe the aerosol concentration change during recirculation. The use of inexpensive, low-efficiency filters in recirculation systems is shown to reduce nanoparticle concentrations to below levels found in a typical office within 3 min while driving through heavy traffic, and within 20 min in a simulated nanomaterial production facility. Development and application of this technology could lead to significant reductions in airborne nanoparticle exposure, reducing possible risks to health and providing solutions for generating nanomaterials safely.

  5. Reducing Underserved Children’s Exposure to Secondhand Smoke

    PubMed Central

    Collins, Bradley N.; Nair, Uma S.; Hovell, Melbourne F.; DiSantis, Katie I.; Jaffe, Karen; Tolley, Natalie; Wileyto, E. Paul; Audrain-McGovern, Janet

    2015-01-01

    Introduction Addressing maternal smoking and child secondhand smoke exposure is a public health priority. Standard care advice and self-help materials to help parents reduce child secondhand smoke exposure is not sufficient to promote change in underserved populations. We tested the efficacy of a behavioral counseling approach with underserved maternal smokers to reduce infant’s and preschooler’s secondhand smoke exposure. Design A two-arm randomized trial: experimental behavior counseling versus enhanced standard care (control). Assessment staff members were blinded. Setting/participants Three hundred randomized maternal smokers were recruited from low-income urban communities. Participants had a child aged <4 years exposed to two or more maternal cigarettes/day at baseline. Intervention Philadelphia Family Rules for Establishing Smokefree Homes (FRESH) included 16 weeks of counseling. Using a behavioral shaping approach within an individualized cognitive–behavioral therapy framework, counseling reinforced efforts to adopt increasingly challenging secondhand smoke exposure–protective behaviors with the eventual goal of establishing a smokefree home. Main outcome measures Primary outcomes were end-of-treatment child cotinine and reported secondhand smoke exposure (maternal cigarettes/day exposed). Secondary outcomes were end-of-treatment 7-day point-prevalence self-reported cigarettes smoked/day and bioverified quit status. Results Participation in FRESH behavioral counseling was associated with lower child cotinine (β= −0.18, p=0.03) and secondhand smoke exposure (β= −0.57, p=0.03) at end of treatment. Mothers in behavioral counseling smoked fewer cigarettes/day (β= –1.84, p=0.03) and had higher bioverified quit rates compared with controls (13.8% vs 1.9%, χ2=10.56, p<0.01). There was no moderating effect of other smokers living at home. Conclusions FRESH behavioral counseling reduces child secondhand smoke exposure and promotes smoking quit

  6. Global burden of aflatoxin-induced hepatocellular carcinoma: a risk assessment.

    PubMed

    Liu, Yan; Wu, Felicia

    2010-06-01

    Hepatocellular carcinoma (HCC), or liver cancer, is the third leading cause of cancer deaths worldwide, with prevalence 16-32 times higher in developing countries than in developed countries. Aflatoxin, a contaminant produced by the fungi Aspergillus flavus and Aspergillus parasiticus in maize and nuts, is a known human liver carcinogen. We sought to determine the global burden of HCC attributable to aflatoxin exposure. We conducted a quantitative cancer risk assessment, for which we collected global data on food-borne aflatoxin levels, consumption of aflatoxin-contaminated foods, and hepatitis B virus (HBV) prevalence. We calculated the cancer potency of aflatoxin for HBV-postive and HBV-negative individuals, as well as the uncertainty in all variables, to estimate the global burden of aflatoxin-related HCC. Of the 550,000-600,000 new HCC cases worldwide each year, about 25,200-155,000 may be attributable to aflatoxin exposure. Most cases occur in sub-Saharan Africa, Southeast Asia, and China where populations suffer from both high HBV prevalence and largely uncontrolled aflatoxin exposure in food. Aflatoxin may play a causative role in 4.6-28.2% of all global HCC cases.

  7. Digital radiography can reduce scoliosis x-ray exposure

    SciTech Connect

    Kling, T.F. Jr.; Cohen, M.J.; Lindseth, R.E.; De Rosa, G.P. )

    1990-09-01

    Digital radiology is a new computerized system of acquiring x-rays in a digital (electronic) format. It possesses a greatly expanded dose response curve that allows a very broad range of x-ray dose to produce a diagnostic image. Potential advantages include significantly reduced radiation exposure without loss of image quality, acquisition of images of constant density irrespective of under or over exposure, and reduced repeat rates for unsatisfactory films. The authors prospectively studied 30 adolescents with scoliosis who had both conventional (full dose) and digital (full, one-half, or one-third dose) x-rays. They found digital made AP and lateral image with all anatomic areas clearly depicted at full and one-half dose. Digital laterals were better at full dose and equal to conventional at one-half dose. Cobb angles were easily measured on all one-third dose AP and on 8 of 10 one-third dose digital laterals. Digital clearly depicted the Risser sign at one-half and one-third dose and the repeat rate was nil in this study, indicating digital compensates well for exposure errors. The study indicates that digital does allow radiation dose to be reduced by at least one-half in scoliosis patients and that it does have improved image quality with good contrast over a wide range of x-ray exposure.

  8. Determinants of formation of aflatoxin-albumin adducts: a seven-township study in Taiwan

    PubMed Central

    Sun, C-A; Wu, D-M; Wang, L-Y; Chen, C-J; You, S-L; Santella, R M

    2002-01-01

    Dietary exposure to aflatoxins is one of the major risk factors for hepatocellular carcinoma. Individual susceptibility to aflatoxin-induced hepatocarcinogenesis may be modulated by both genetic and environmental factors affecting metabolism. A cross-sectional study was performed to evaluate determinants of the formation of aflatoxin covalently bound to albumin (AFB1-albumin adducts). A total of 474 subjects who were free of liver cancer and cirrhosis and were initially selected as controls for previous case–control studies of aflatoxin-induced hepatocarcinogenesis in Taiwan, were employed in this study. Aflatoxin-albumin adducts were determined by competitive enzyme-linked immunosorbent assay, hepatitis B surface antigen and antibodies to hepatitis C virus by enzyme immunoassay, as well as genotypes of glutathione S-transferase M1-1 and T1-1 by polymerase chain reaction. The detection rate of AFB1-albumin adducts was significantly higher in males (42.5%) than in females (21.6%) (multivariate-adjusted odds ratio=2.6, 95% confidence interval=1.4–5.0). The formation of detectable albumin adducts was moderately higher in hepatitis B surface antigen carriers (42.8%) than in non-carriers (36.6%) (multivariate-adjusted odds ratio=1.4, 95% confidence interval=1.0–2.1). In addition, the detection rate of AFB1-albumin adducts tended to increase with the increasing number of null genotypes of glutathione S-transferase M1-1 and glutathione S-transferase T1-1. In conclusion, this cross-sectional study has assessed the relative contributions of environmental exposure and host susceptibility factors in the formation of AFB1-albumin adducts in a well characterised Chinese adult population. This study further emphasises the necessity to reduce aflatoxin exposure in people living in an area endemic for chronic hepatitis B virus infection. British Journal of Cancer (2002) 87, 966–970. doi:10.1038/sj.bjc.6600584 www.bjcancer.com © 2002 Cancer Research UK PMID:12434285

  9. Reducing population stratification bias: stratum matching is better than exposure.

    PubMed

    Lee, Wen-Chung; Wang, Liang-Yi

    2009-01-01

    Genetic studies of complex human diseases rely heavily on the epidemiologic association paradigm, particularly the population-based case-control designs. This study aims to compare the matching effectiveness in terms of bias reduction between exposure matching and stratum matching. Formulas for population stratification bias were derived. An index of matching effectiveness was constructed to compare the two types of matching. It was found that exposure matching can paradoxically increase the magnitude of population stratification bias sometimes, whereas stratum matching can guarantee to reduce it. The authors propose two simple rules for genetic association studies: (a) to match on anything that helps to delineate population strata such as race, ethnicity, nationality, ancestry, and birthplace and (b) to match on an exposure only when it is a strong predictor of the disease and is expected to have great variation in prevalence across population strata.

  10. Aflatoxin metabolism in humans: detection of metabolites and nucleic acid adducts in urine by affinity chromatography

    SciTech Connect

    Groopman, J.D.; Donahue, P.R.; Zhu, J.Q.; Chen, J.S.; Wogan, G.N.

    1985-10-01

    A high-affinity IgM monoclonal antibody specific for aflatoxins was covalently bound to Sepharose 4B and used as a preparative column to isolate aflatoxin derivatives from the urine of people and experimental animals who had been exposed to the carcinogen environmentally or under laboratory conditions. Aflatoxin levels were quantified by radioimmunoassay and high-performance liquid chromatography after elution from the affinity column. In studies on rats injected with ( UC)aflatoxin B1, the authors identified the major aflatoxin-DNA adduct, 2,3-dihydro-2-(N7-guanyl)-3-hydroxy-aflatoxin B1 (AFB1-N7-Gua), and the oxidative metabolites M1 and P1 as the major aflatoxin species present in the urine. When this methodology was applied to human urine samples obtained from people from the Guangxi Province of China exposed to aflatoxin B1 through dietary contamination, the aflatoxin metabolites detected were also AFB1-N7-Gua and aflatoxins M1 and P1. Therefore, affinity chromatography using a monoclonal antibody represents a useful and rapid technique with which to isolate this carcinogen and its metabolites in biochemical epidemiology and for subsequent quantitative measurements, providing exposure information that can be used for risk assessment.

  11. Effect of methionine and lactic acid bacteria as aflatoxin binder on broiler performance

    NASA Astrophysics Data System (ADS)

    Istiqomah, Lusty; Damayanti, Ema; Julendra, Hardi; Suryani, Ade Erma; Sakti, Awistaros Angger; Anggraeni, Ayu Septi

    2017-06-01

    The use of aflatoxin binder product based amino acids, lacic acid bacteria, and natural product gived the opportunity to be an alternative biological decontamination of aflatoxins. A study was conducted to determine the efficacy of aflatoxin binder administration (amino acid methionine and lactic acid bacteria (Lactobacillus plantarum G7)) as feed additive on broiler performance. In this study, 75 Lohmann unsexed day old chicks were distributed randomly into 5 units of cages, each filled with 15 broilers. Five cages were assigned into 5 treatments groups and fed with feed contained aflatoxin. The treatments as follow: P1 (aflatoxin feed without aflatoxin binder), P3 (aflatoxin feed + 0.8% of methionine + 1% of LAB), P4 (aflatoxin feed + 1.2% of methionine + 1% of LAB), P5 (aflatoxin feed + 1% of LAB), and K0 (commercial feed). The measurement of aflatoxin content in feed was performed by Enzyme Linked Immunosorbent Assay method using AgraQuant® Total Aflatoxin Assay Romer Labs procedure. The experimental period was 35 days with feeding and drinking ad libitum. LAB was administered into drinking water, while methionine into feed. Vaccination program of Newcastle Disease (ND) was using active vaccine at 4 and 18 day old, while Infectious Bursal Disease (IBD) was given at 8 day old. Parameter of body weight was observed weekly, while feed consumption noted daily. The result showed that aflatoxin in feed for 35 days period did not significantly affect the body weight gain and feed conversion. The lowest percentage of organ damage at 21 day old was found in P5 treatment (55%), while at 35day old was found in P4 treatment (64%). It could be concluded that technological process of detoxifying aflatoxin could be applied in an attempt to reduce the effect on the toxicity of aflatoxin in poultry feed.

  12. Clinical Trials Methods for Evaluation of Potential Reduced Exposure Products

    PubMed Central

    Hatsukami, Dorothy K.; Hanson, Karen; Briggs, Anna; Parascandola, Mark; Genkinger, Jeanine M.; O'Connor, Richard; Shields, Peter

    2009-01-01

    Potential reduced exposure tobacco products (PREPs) may have promise in reducing tobacco-related morbidity or mortality or may promote greater harm to individuals or the population. Critical to determining the risks or benefits from these products are valid human clinical trial PREP assessment methods. Assessment involves determining the effects of these products on biomarkers of exposure and of effect, which serve as proxies for harm, and assessing the potential for consumer uptake and abuse of the product. This article raises the critical methodological issues associated with PREP assessment, reviews the methods that have been used to assess PREPs, and describes the strengths and limitations of these methods. Additionally, recommendations for clinical trials PREP assessment methods and future research directions in this area based on this review and on the deliberations from a National Cancer Institute sponsored Clinical Trials PREP Methods Workshop are provided. PMID:19959672

  13. Effect of dietary selenium on the metabolism of aflatoxin B1 in turkeys.

    PubMed

    Gregory, J F; Edds, G T

    1984-08-01

    To investigate the biochemical mechanism of the previously reported protective effect of dietary selenium against aflatoxin toxicity, the hepatic metabolism of aflatoxin B1 in turkey poults was examined at various dietary selenium concentrations. Diets were supplemented with 0.2, 2.0 or 4.0 ppm selenium (as sodium selenite) and 500 ng aflatoxin B1/g diet in an 18-day trial. Free and conjugated aflatoxin and metabolites were quantified using high-performance liquid chromatography. The proportion of liver aflatoxins in conjugated forms increased and the ratio of free aflatoxin B1/M1 decreased with increasing dietary selenium concentrations. These in vivo results provide evidence of selenium-induced enhancement of aflatoxin detoxification processes. In a similar experiment using 2.0 ppm selenium and 750 ng aflatoxin B1/g diet, the concentration of hepatic reduced glutathione, cytochrome P-450 and the activity of enzymes involved in the metabolism of aflatoxin B1 and glutathione were determined. Although the selenium supplement increased glutathione peroxidase activity, dietary selenium had no effect on reduced glutathione or cytochrome P-450 concentrations or on the activities of glutathione transferase E, glucuronyl transferase and cytochrome c reductase. These data indicate that the protective action of selenium is not mediated by an increase in glutathione availability for aflatoxin conjugation or by effects on the activities of these enzymes as measured in vitro.

  14. Pulmonary interstitial fibrosis with evidence of aflatoxin B1 in lung tissue

    SciTech Connect

    Dvorackova, I.; Pichova, V.

    1986-01-01

    Three cases of pulmonary interstitial fibrosis, two in agricultural workers and one in a textile worker, are reported. In lung samples of all three patients the presence of aflatoxin B1 was demonstrated by radioimmunoassay (RIA). A possible occupational risk of aflatoxin exposure via the respiratory tract is suggested.

  15. Evaluating oral noncombustible potential-reduced exposure products for smokers

    PubMed Central

    Eissenberg, Thomas

    2010-01-01

    Introduction: Potential-reduced exposure products (PREPs) are marketed as a way for smokers to continue using tobacco while possibly lessening their tobacco toxicant intake. Some tobacco-based PREPs are combustible and intended to be smoked, while others are noncombustible and intended to be administered orally (e.g., Camel Snus [CS] tobacco sachets and Ariva tobacco tablets). The ability of these noncombustible PREPs to reduce smokers’ exposure to cigarette-delivered toxicants and suppress tobacco abstinence symptoms effectively is unclear. Clinical laboratory methods have been used to measure combustible PREP-associated toxicant exposure and abstinence symptom suppression and could be applied to evaluating the effects of orally administered noncombustible PREPs. Methods: In this study, 21 smokers (6 women) participated in four 5-day conditions that differed by product used: CS, Ariva, own brand cigarettes, or no tobacco. Measures included expired-air carbon monoxide (CO), the urinary metabolite of nicotine (cotinine), the urinary metabolite of the carcinogen NNK (NNAL-T), and subjective effect ratings. Results: Relative to own brand, all other conditions were associated with CO and cotinine levels that were lower and abstinence symptom ratings that were greater. Only no-tobacco use was associated with significantly lower NNAL levels. Acceptability ratings were also lower in all conditions relative to own brand. Discussion: Although these oral products reduce exposure to CO, their ineffective abstinence symptom suppression and low acceptability may limit their viability as PREPs. As with combustible PREPs, clinical laboratory study of orally administered noncombustible PREPs will be a valuable part of any comprehensive PREP evaluation strategy. PMID:20159791

  16. Low-dose cardiac imaging: reducing exposure but not accuracy.

    PubMed

    Small, Gary R; Chow, Benjamin J W; Ruddy, Terrence D

    2012-01-01

    Cardiac imaging techniques that use ionizing radiation have become an integral part of current cardiology practice. However, concern has arisen that ionizing radiation exposure, even at the low levels used for medical imaging, is associated with the risk of cancer. From a single diagnostic cardiac imaging procedure, such risks are low. On a population basis, however, malignancies become more likely on account of stochastic effects being more probable as the number of procedures performed increases. In light of this, and owing to professional and industrial commitment to the as low as reasonably achievable (ALARA) principle, over the last decade major strides have been made to reduce radiation dose in cardiac imaging. Dose-reduction strategies have been most pronounced in cardiac computed tomography. This was important since computed tomography has rapidly become a widely used diagnostic alternative to invasive coronary angiography, and initial protocols were associated with relatively high radiation exposures. Advances have also been made in nuclear cardiology and in invasive coronary angiography, and these reductions in patient exposure have all been achieved with maintenance of image quality and accuracy. Improvements in imaging camera technology, image acquisition protocols and image processing have lead to reductions in patient radiation exposure without compromising imaging diagnostic accuracy.

  17. Production of Aflatoxin on Rice

    PubMed Central

    Shotwell, Odette L.; Hesseltine, C. W.; Stubblefield, R. D.; Sorenson, W. G.

    1966-01-01

    A method has been developed for the production of aflatoxin by growing Aspergillus flavus strain NRRL 2999 on the solid substrate rice. Optimal yields, more than 1 mg of aflatoxin B1 per g of starting material, were obtained in 5 days at 28 C. A crude product containing aflatoxins was isolated by chloroform extraction and precipitation with hexane from concentrated solutions. The crude product consisted of 50% aflatoxin in the following ratio: B1-B2-G1-G2, 100:0.15:0.22:0.02. Aflatoxin B1 was separated from almost all the impurities and from the other aflatoxins by chromatography on silica gel with 1% ethyl alcohol in chloroform. Analytically pure aflatoxin B1 was recrystallized from chloroform-hexane mixtures. Images Fig. 1 PMID:5970829

  18. Aflatoxin: A 50-Year Odyssey of Mechanistic and Translational Toxicology

    PubMed Central

    Kensler, Thomas W.; Roebuck, Bill D.; Wogan, Gerald N.; Groopman, John D.

    2011-01-01

    Since their discovery 50 years ago, the aflatoxins have become recognized as ubiquitous contaminants of the human food supply throughout the economically developing world. The adverse toxicological consequences of these compounds in populations are quite varied because of a wide range of exposures leading to acute effects, including rapid death, and chronic outcomes such as hepatocellular carcinoma. Furthermore, emerging studies describe a variety of general adverse health effects associated with aflatoxin, such as impaired growth in children. Aflatoxin exposures have also been demonstrated to multiplicatively increase the risk of liver cancer in people chronically infected with hepatitis B virus (HBV) illustrating the deleterious impact that even low toxin levels in the diet can pose for human health. The public health impact of aflatoxin exposure is pervasive. Aflatoxin biomarkers of internal and biologically effective doses have been integral to the establishment of the etiologic role of this toxin in human disease through better estimates of exposure, expanded knowledge of the mechanisms of disease pathogenesis, and as tools for implementing and evaluating preventive interventions. PMID:20881231

  19. Aflatoxin: a 50-year odyssey of mechanistic and translational toxicology.

    PubMed

    Kensler, Thomas W; Roebuck, Bill D; Wogan, Gerald N; Groopman, John D

    2011-03-01

    Since their discovery 50 years ago, the aflatoxins have become recognized as ubiquitous contaminants of the human food supply throughout the economically developing world. The adverse toxicological consequences of these compounds in populations are quite varied because of a wide range of exposures leading to acute effects, including rapid death, and chronic outcomes such as hepatocellular carcinoma. Furthermore, emerging studies describe a variety of general adverse health effects associated with aflatoxin, such as impaired growth in children. Aflatoxin exposures have also been demonstrated to multiplicatively increase the risk of liver cancer in people chronically infected with hepatitis B virus (HBV) illustrating the deleterious impact that even low toxin levels in the diet can pose for human health. The public health impact of aflatoxin exposure is pervasive. Aflatoxin biomarkers of internal and biologically effective doses have been integral to the establishment of the etiologic role of this toxin in human disease through better estimates of exposure, expanded knowledge of the mechanisms of disease pathogenesis, and as tools for implementing and evaluating preventive interventions.

  20. Aflatoxin decomposition in various soils

    SciTech Connect

    Angle, J.S.

    1986-08-01

    The persistence of aflatoxin in the soil environment could potentially result in a number of adverse environmental consequences. To determine the persistence of aflatoxin in soil, /sup 14/C-labeled aflatoxin B1, was added to silt loam, sandy loam, and silty clay loam soils and the subsequent release of /sup 14/CO/sub 2/ was determined. After 120 days of incubation, 8.1% of the original aflatoxin added to the silt loam soil was released as CO/sub 2/. Aflatoxin decomposition in the sandy loam soil proceeded more quickly than the other two soils for the first 20 days of incubation. After this time, the decomposition rate declined and by the end of the study, 4.9% of the aflatoxin was released as CO/sub 2/. Aflatoxin decomposition proceeded most slowly in the silty clay loam soil. Only 1.4% of aflatoxin added to the soil was released as CO/sub 2/ after 120 days incubation. To determine whether aflatoxin was bound to the silty clay loam soil, aflatoxin B1 was added to this soil and incubated for 20 days. The soil was periodically extracted and the aflatoxin species present were determined using thin layer chromatographic (TLC) procedures. After one day of incubation, the degradation products, aflatoxins B2 and G2, were observed. It was also found that much of the aflatoxin extracted from the soil was not mobile with the TLC solvent system used. This indicated that a conjugate may have formed and thus may be responsible for the lack of aflatoxin decomposition.

  1. Fluorometric assay for aflatoxins

    SciTech Connect

    Chakrabarti, A.G.

    1984-11-01

    The method that is now widely adopted by the government laboratories for the assay of individual aflatoxin components (B/sub 1/, B/sub 2/, G/sub 1/, and G/sub 2/) utilizes a TLC technique. The extraction and clean-up steps of this technique were further researched but the method is still time consuming. It is, therefore, very important to develop a rapid and accurate assay technique for aflatoxins. The current research proposes a technique which utilizes a Turner Fluorometer.

  2. Apple juice greatly reduces systemic exposure to atenolol.

    PubMed

    Jeon, Hyewon; Jang, In-Jin; Lee, SeungHwan; Ohashi, Kyoichi; Kotegawa, Tsutomu; Ieiri, Ichiro; Cho, Joo-Youn; Yoon, Seo Hyun; Shin, Sang-Goo; Yu, Kyung-Sang; Lim, Kyoung Soo

    2013-01-01

    Fruit juice reduces the plasma concentrations of several β-adrenoceptor blockers, likely by inhibiting OATP2B1-mediated intestinal absorption. The aim of this study was to investigate the effects of apple juice on the pharmacokinetics of atenolol. Twelve healthy Korean volunteers with genotypes of SLCO2B1 c.1457C> T (*1/*1 (n = 6) and *3/*3 (n = 6)) were enrolled in this study. In a three-phase, one-sequence crossover study, the pharmacokinetics (PK) of atenolol was evaluated after administration of 50 mg atenolol. Subjects received atenolol with either 300 ml water, 1200 ml apple juice or 600 ml apple juice. Apple juice markedly reduced the systemic exposure to atenolol. The geometric mean ratios (95% confidence intervals) of apple juice : water were 0.18 (0.13, 0.25, 1200 ml) and 0.42 (0.30, 0.59, 600 ml) for the AUC(0,t(last)). In this study, the PK parameters of atenolol responded in a dose-dependent manner to apple juice. Apple juice markedly reduced systemic exposure to atenolol. The genetic variation of SLCO2B1 c.1457C>T had a minimal effect on the pharmacokinetics of atenolol when the drug was administered with water or apple juice. © 2012 The Authors. British Journal of Clinical Pharmacology © 2012 The British Pharmacological Society.

  3. Apple juice greatly reduces systemic exposure to atenolol

    PubMed Central

    Jeon, Hyewon; Jang, In-Jin; Lee, SeungHwan; Ohashi, Kyoichi; Kotegawa, Tsutomu; Ieiri, Ichiro; Cho, Joo-Youn; Yoon, Seo Hyun; Shin, Sang-Goo; Yu, Kyung-Sang; Lim, Kyoung Soo

    2013-01-01

    AIM Fruit juice reduces the plasma concentrations of several β-adrenoceptor blockers, likely by inhibiting OATP2B1-mediated intestinal absorption. The aim of this study was to investigate the effects of apple juice on the pharmacokinetics of atenolol. METHODS Twelve healthy Korean volunteers with genotypes of SLCO2B1 c.1457C> T (*1/*1 (n= 6) and *3/*3 (n= 6)) were enrolled in this study. In a three-phase, one-sequence crossover study, the pharmacokinetics (PK) of atenolol was evaluated after administration of 50 mg atenolol. Subjects received atenolol with either 300 ml water, 1200 ml apple juice or 600 ml apple juice. RESULTS Apple juice markedly reduced the systemic exposure to atenolol. The geometric mean ratios (95% confidence intervals) of apple juice : water were 0.18 (0.13, 0.25, 1200 ml) and 0.42 (0.30, 0.59, 600 ml) for the AUC(0,tlast). In this study, the PK parameters of atenolol responded in a dose-dependent manner to apple juice. CONCLUSIONS Apple juice markedly reduced systemic exposure to atenolol. The genetic variation of SLCO2B1 c.1457C>T had a minimal effect on the pharmacokinetics of atenolol when the drug was administered with water or apple juice. PMID:22574741

  4. Measures for Assessing Subjective Effects of Potential Reduced Exposure Products

    PubMed Central

    Hanson, Karen; O’Connor, Richard; Hatsukami, Dorothy

    2009-01-01

    Potential reduced exposure products (PREPs) may reduce toxicant exposure and thereby may possibly reduce health risks associated with conventional tobacco use. However, lessened health risk to the individual or harm to the population through use of PREPs is unknown. Research is being conducted to evaluate the possible health effects associated with PREP use. As part of this evaluation, it is critical to provide sound measures of subjective responses to PREPs to determine the use and the abuse potential of a product, that is the likelihood that this product will lead to addiction. The goal of this paper is to conduct a systematic review of scales that have been used to measure the subjective responses to PREPs and examine their characteristics. In this paper, scales are identified and the items on the scales are described. Scales are also examined to determine whether they are sensitive in testing PREPs. Furthermore, scales to assess PREPs are recommended to investigators. Where no scales exist, items that may be critical for the development and validation of new scales are identified. PMID:19959674

  5. Reducing uncertainty in risk modeling for methylmercury exposure

    SciTech Connect

    Ponce, R.; Egeland, G.; Middaugh, J.; Lee, R.

    1995-12-31

    The biomagnification and bioaccumulation of methylmercury in marine species represents a challenge for risk assessment related to the consumption of subsistence foods in Alaska. Because of the profound impact that food consumption advisories have on indigenous peoples seeking to preserve a way of life, there is a need to reduce uncertainty in risk assessment. Thus, research was initiated to reduce the uncertainty in assessing the health risks associated with the consumption of subsistence foods. Because marine subsistence foods typically contain elevated levels of methylmercury, preliminary research efforts have focused on methylmercury as the principal chemical of concern. Of particular interest are the antagonistic effects of selenium on methylmercury toxicity. Because of this antagonism, methylmercury exposure through the consumption of marine mammal meat (with high selenium) may not be as toxic as comparable exposures through other sources of dietary intake, such as in the contaminated bread episode of Iraq (containing relatively low selenium). This hypothesis is supported by animal experiments showing reduced toxicity of methylmercury associated with marine mammal meat, by the antagonistic influence of selenium on methylmercury toxicity, and by negative clinical findings in adult populations exposed to methylmercury through a marine diet not subject to industrial contamination. Exploratory model development is underway to identify potential improvements and applications of current deterministic and probabilistic models, particularly by incorporating selenium as an antagonist in risk modeling methods.

  6. Selenomethionine reduces visual deficits due to developmental methylmercury exposures

    PubMed Central

    Weber, Daniel N.; Connaughton, Victoria P.; Dellinger, John A.; Klemer, David; Udvadia, Ava; Carvan, Michael J.

    2008-01-01

    Developmental exposures to methylmercury (MeHg) have life-long behavioral effects. Many micronutrients, including selenium, are involved in cellular defenses against oxidative stress and may reduce the severity of MeHg-induced deficits. Zebrafish embryos (<4 hours post fertilization, hpf) were exposed to combinations of 0.0-0.30 μM MeHg and/or selenomethionine (SeMet) until 24 hpf then placed in clean medium. Fish were tested as adults under low light conditions (~60 μW/m2) for visual responses to a rotating black bar. Dose-dependent responses to MeHg exposure were evident (ANOVA, P<0.001) as evidenced by reduced responsiveness, whereas SeMet did not induce deficits except at 0.3 μM,. Ratios of SeMet:MeHg of 1:1 or 1:3 resulted in responses that were indistinguishable from controls (ANOVA, P<0.001). No gross histopathologies were observed (H&E stain) in the retina or optic tectum at any MeHg concentration. Whole-cell, voltage-gated, depolarization-elicited outward K+ currents of bipolar cells in intact retina of slices adult zebrafish were recorded and outward K+ current amplitude was larger in bipolar cells of MeHg-treated fish. This was due to the intense response of cells expressing the delayed rectifying IK current; cells expressing the transient IA current displayed a slight trend for smaller amplitude among MeHg-treated fish. Developmental co-exposure to SeMet reduced but did not eliminate the increase in the MeHg-induced IK response, however, IA responses increased significantly over MeHg-treated fish to match control levels. Electrophysiological deficits parallel behavioral patterns in MeHg-treated fish, i.e., initial reactions to the rotating bar were followed by periods of inactivity and then a resumption of responses. PMID:17905328

  7. Smoking behaviour and toxin exposure during six weeks use of a potential reduced exposure product: Omni.

    PubMed

    Hughes, J R; Hecht, S S; Carmella, S G; Murphy, S E; Callas, P

    2004-06-01

    To determine smoking behaviour, acceptability, and toxin exposure when smokers switch to the potential reduced exposure product-Omni cigarette. 12 week randomised, crossover study of Omni versus own cigarettes. 19 light/ultralight and 15 regular smokers. Cigarettes/day, smoking topography, craving, withdrawal symptoms, urinary cotinine plus its glucuronide (total cotinine), nicotine plus its glucuronide (total nicotine), and carcinogen metabolites (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol plus its glucuronides and 1-hydroxypyrene). When switched to Omni, smokers smoked the same number of cigarettes/day, smoked Omni cigarettes less intensely (total puff volume = -11%) and had slightly lower total cotinine (-18%) levels than their own cigarettes, but had a slightly greater carbon monoxide boost/cig (+21%). Craving and withdrawal ratings were similar with Omni and own cigarettes. Carcinogen metabolite levels were somewhat but not significantly lower with Omni. About half of smokers rated Omni as better for their health and about two thirds stated it was weaker and worse tasting than their own cigarettes. Although Omni may be an adequate behavioural and pharmacological substitute for traditional cigarettes, it may not decrease carcinogen exposure and may increase carbon monoxide. Replications with larger sample sizes and longer follow up are needed. These results indicate the need for regulation of reduced exposure and reduced risk claims.

  8. A model of interaction: aflatoxins and hepatitis viruses in liver cancer aetiology and prevention.

    PubMed

    Wild, Christopher P; Montesano, Ruggero

    2009-12-01

    Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide and has an extremely poor prognosis. The majority of cases occur in south-east Asia and sub-Saharan Africa where the major risk factors are chronic infection with hepatitis B and C viruses (HBV and HCV) as well as dietary exposure to aflatoxins. Aflatoxin B1, the most commonly occurring and potent of the aflatoxins is associated with a specific AGG to AGT transversion mutation at codon 249 of the p53 gene in human HCC, providing mechanistic support to a causal link between exposure and disease. Prospective epidemiological studies have shown a more than multiplicative interaction between HBV and aflatoxins in terms of HCC risk. However, the biology underlying this statistical interaction is not fully understood. There are a number of potential mechanisms including, among others: the fixation of AFB1-induced mutations in the presence of liver regeneration and hyperplasia induced by chronic HBV infection; the predisposition of HBV-infected hepatocytes to aflatoxin-induced DNA damage; an increase in susceptibility to chronic HBV infection in aflatoxin-exposed individuals; and oxidative stress exacerbated by co-exposure to aflatoxins and chronic hepatitis infection. Priorities for prevention are global HBV vaccination, primary and secondary prevention strategies against aflatoxin and the avoidance of transmission of HCV through good hygiene practices.

  9. Socio-demographic determinants of aflatoxin B1-lysine adduct levels among pregnant women in Kumasi, Ghana.

    PubMed

    Shuaib, F M B; Jolly, P E; Ehiri, J E; Ellis, W O; Yatich, N J; Funkhouser, E; Person, S D; Williams, J H; Qian, G; Wang, J-S

    2012-12-01

    Aflatoxins are fungal metabolites that contaminate staple food crops in many developing countries. Although studies have linked these toxins to adverse birth outcomes and poor infant development, no study has investigated the socio-demographic and economic determinants of aflatoxin levels among pregnant women living in sub-Saharan Africa. A cross-sectional study was conducted among 785 pregnant women in Kumasi. Aflatoxin B1 lysine adduct levels (AF-ALB) were determined by High Performance Liquid Chromatography. Analysis of variance was used to determine mean log AF-ALB levels and significance of differences in these levels according to socio-demographic variables. Logistic regression was used to identify independent associations of socio-demographics with having AF-ALB levels (≥ 11.34 pg/mg; upper quartile). AF-ALB levels ranged from 0.44 pg/mg to 268.73 pg/mg albumin with a median level of 5.0 pg/mg. Bivariate analyses indicates that mean ln AF-ALB as well as the percent of women having high AF-ALB levels (≥ 11.34 pg/mg; upper quartile) were inversely associated with indices of higher socioeconomic status: higher education and income, being employed and having a flush toilet. Higher income, being employed, having one child (verses no children) and having a flush toilet (verses no toilet facilities) were each independently associated with a 30-40% reduced odds of high AF-ALB levels. Additional research is needed to investigate how socio-demographic and economic factors interact to influence aflatoxin ingestion by individuals in regions with high aflatoxin crop contamination. This knowledge can be used to formulate and implement policies that will reduce exposure of women and their unborn children to these toxins.

  10. Proactive Regulation Reduces Asbestos Exposures in Lake County, CA

    NASA Astrophysics Data System (ADS)

    Gearhart, D.; Ley, J. F.

    2012-12-01

    The Lake County Air Quality Management District adopted its rule for Naturally Occurring Asbestos (NOA) in 1996 with the goal of preventing impacts and exposures through education, proactive project design, and common sense. Utilizing detailed GIS mapping and streamlined mitigation measures, the District maintains an effective program to reduce the hazard of NOA in our community. Measures for NOA are also incorporated into the County Grading Ordinance, and most small projects fall under those rules. Larger projects require a Serpentine Dust Control Plan from the District that provides clear mitigation measures, with the focus primarily on dust prevention. This cooperative approach results in a comprehensive effort to minimize potential health hazards from naturally occurring asbestos. Compliance is more easily achieved when workers are informed of the hazards and potential for exposure, and the rules/mitigation measures are clear and simple. Informed individuals generally take prompt corrective action to protect themself and those around them from the potential for breathing asbestos-containing dust. This proactive program results in improved community health by preventing exposure to asbestos.

  11. [Aflatoxins--health risk factors].

    PubMed

    Miliţă, Nicoleta Manuela; Mihăescu, Gr; Chifiriuc, Carmen

    2010-01-01

    Aflatoxins are secondary metabolites produced by a group of strains, mainly Aspergillus and Penicillium species. These mycotoxins are bifurano-coumarin derivatives group with four major products B1, B2, G1 and G2 according to blue or green fluorescence emitted in ultraviolet light and according to chromatographic separation. After metabolism of aflatoxin B1 and B2 in the mammalian body, result two metabolites M1 and M2 as hydroxylated derivatives of the parent compound. Aflatoxins have high carcinogenic potential, the most powerful carcinogens in different species of animals and humans. International Agency for Research on Cancer has classified aflatoxin B1 in Group I carcinogens. The target organ for aflatoxins is the liver. In chronic poisoning, aflatoxin is a risk to health, for a long term causing cancer (hepatocellular carcinoma), and in acute intoxications aflatoxin is lethal. This work purpose to discuss aflatoxins issue: the synthesis, absorption and elimination of aflatoxins, the toxicity mechanisms, and measures to limit the content of aflatoxins in food

  12. Development of a fluorescence polarization assay for the determination of aflatoxins in grains.

    PubMed

    Nasir, Mohammad Sarwar; Jolley, Michael E

    2002-05-22

    Aflatoxins produced by Aspergillus flavus are commonly found in human and animal foods including grains, cereals, peanut products, sorghum, and soy seeds. Exposure to aflatoxins has been associated with carcinogenicity. This paper reports a simple, portable, and rapid fluorescence polarization (FP) assay for aflatoxin determination in grains. This immunoassay is field portable, homogeneous, and without any washing and cleaning steps. The assay is based upon the competition between free aflatoxin and an aflatoxin-fluorescein tracer for an aflatoxin-specific monoclonal antibody in solution. A series of naturally contaminated corn, sorghum, peanut butter, and peanut paste samples were analyzed by FP and compared with HPLC results. Similarly, spiked popcorn samples were analyzed by FP. FP results of naturally contaminated samples correlated well with HPLC (r (2) = 0.97). FP analysis of spiked popcorn samples (with a mixture of B(1)/B(2)/G(1)/G(2), 7/1/3/1, w/w) gave a good correlation with spiked values (r (2) = 0.99). However, FP consistently underestimated the aflatoxin contents. This was perhaps due to low cross-reactivity of the antibody used toward B(2), G(1), and G(2) aflatoxins. These results combined with the portability and simplicity of the assay suggest that the assay can be used for screening total aflatoxin in grains.

  13. Occurrence of aflatoxins and its management in diverse cropping systems of central Tanzania.

    PubMed

    Seetha, Anitha; Munthali, Wills; Msere, Harry W; Swai, Elirehema; Muzanila, Yasinta; Sichone, Ethel; Tsusaka, Takuji W; Rathore, Abhishek; Okori, Patrick

    2017-08-07

    The staple crops, maize, sorghum, bambara nut, groundnut, and sunflower common in semi-arid agro-pastoral farming systems of central Tanzania are prone to aflatoxin contamination. Consumption of such crop produce, contaminated with high levels of aflatoxin B1 (AFB1), affects growth and health. In this paper, aflatoxin contamination in freshly harvested and stored crop produce from central Tanzania was examined, including the efficacy of aflatoxin mitigation technologies on grain/kernal quality. A total of 312 farmers were recruited, trained on aflatoxin mitigation technologies, and allowed to deploy the technologies for 2 years. After 2 years, 188 of the 312 farmers were tracked to determine whether they had adopted and complied with the mitigation practices. Aflatoxigenic Aspergillus flavus and aflatoxin B1 contamination in freshly harvested and stored grains/kernels were assessed. A. flavus frequency and aflatoxin production by fungi were assayed by examining culture characteristics and thin-layer chromatography respectively. AFB1 was assayed by enzyme-linked immunosorbent assay. The average aflatoxin contamination in freshly harvested samples was 18.8 μg/kg, which is above the acceptable standard of 10 μg/kg. Contamination increased during storage to an average of 57.2 μg/kg, indicating a high exposure risk. Grains and oilseeds from maize, sorghum, and sunflower produced in aboveground reproductive structures had relatively low aflatoxin contamination compared to those produced in geocarpic structures of groundnut and bambara nut. Farmers who adopted recommended post-harvest management practices had considerably lower aflatoxin contamination in their stored kernels/grains. Furthermore, the effects of these factors were quantified by multivariate statistical analyses. Training and behavioral changes by farmers in their post-harvest practice minimize aflatoxin contamination and improve food safety. Moreover, if non-trained farmers receive mitigation

  14. Nitrogen fertilizer influence on aflatoxin contamination of corn in Louisiana.

    PubMed

    Tubajika, K M; Mascagni, H J; Damann, K E; Russin, J S

    1999-12-01

    Studies were conducted in 1997 and 1998 on a Gigger silt loam at the Macon Ridge Research Station at Winnsboro, LA, to determine the influence of nitrogen (N) rate, timing, and starter nitrogen fertilizer on aflatoxin contamination in corn. Fertilizer N (0, 50, 100, 150, 200, and 250 lb of N/acre), two timings (at planting and six-leaf stage), and starter N fertilizer (a control and 10 lb of N/acre applied in furrow) were evaluated. Application of starter, N rates, and the interaction of starter with N timing and N rates significantly affected aflatoxin levels. Rates of 50-250 lb of N/acre were 34-43% lower in aflatoxin contamination than plots receiving no N. The application of 10 lb of N/acre starter reduced the aflatoxin levels by 20% compared to the no-starter control.

  15. Product identification and safety evaluation of aflatoxin B1 decontaminated by electrolyzed oxidizing water.

    PubMed

    Xiong, Ke; Liu, Hai jie; Li, Li te

    2012-09-26

    In this study with aflatoxin-contaminated peanuts, the effectiveness of electrolyzed oxidizing water (EOW) in the decontamination of aflatoxin B(1) was investigated. The aflatoxin B(1) content was markedly reduced upon treatment with EOW, particularly with neutral electrolyzed oxidizing water (NEW). The conversion product of EOW treatment was isolated and identified as 8-chloro-9-hydroxy aflatoxin B(1) (compound 1), which is an amphiphilic molecule, in contrast to fat-soluble aflatoxin B(1). A mutagenic response study revealed that the number of revertants per plate after treatment of bacterial strains TA-97, TA-98, TA-100, and TA-102 with NEW was within the standard value range. The HepG2 cell viability assay yielded an IC(50) value of compound 1 approximately 150 mM. This study indicates that EOW had the ability to decontaminate aflatoxin B(1), and the conversion product, compound 1, did not exhibit mutagenic activity or cytotoxic effects.

  16. Global geographical overlap of aflatoxin and hepatitis C: controlling risk factors for liver cancer worldwide.

    PubMed

    Palliyaguru, D L; Wu, F

    2013-01-01

    About 85% of hepatocellular carcinoma (HCC, liver cancer) cases occur in low-income countries, where the risk factors of dietary aflatoxin exposure and chronic hepatitis B and C (HBV and HCV) viral infection are common. While studies have shown synergism between aflatoxin and HBV in causing HCC, much less is known about whether aflatoxin and HCV synergise similarly. From an exposure perspective, it was examined whether there is a geographical overlap in populations worldwide exposed to high dietary aflatoxin levels and with high HCV prevalence. While HCV is one of the most important risk factors for HCC in high-income nations (where aflatoxin exposure is low), it is found that HCV prevalence is much higher in Africa and Asia, where aflatoxin exposure is also high. However, within a given world region, there are some inconsistencies regarding exposure and cancer risk. Therefore, there is a need to control risk factors such as aflatoxin and hepatitis viruses in a cost-effective manner to prevent global HCC, while continuing to evaluate biological mechanisms by which these risk factors interact to increase HCC risk.

  17. Aflatoxin production in meats. II. Aged dry salamis and aged country cured hams.

    PubMed

    Bullerman, L B; Hartman, P A; Ayres, J C

    1969-11-01

    Italian-type salamis contaminated with Aspergillus flavus were more likely to develop aflatoxins during aging than were smoked Hungarian-type salamis under the same conditions. Temperatures below 15 C and humidities of less than 75% were found to prevent aflatoxin development during the aging of salami. The aging of salami for 8 weeks and the presence of curing ingredients, especially pepper and sodium nitrite, tended to reduce the amounts of aflatoxins found. Aflatoxins were produced by A. flavus and A. parasiticus on 6- to 9-month-old country cured hams during aging when the temperature approached 30 C.

  18. Ethylene Inhibits Aflatoxin Biosynthesis in Aspergillus parasiticus Grown on Peanuts

    PubMed Central

    Gunterus, A.; Roze, L.V.; Beaudry, R.; Linz, J. E.

    2007-01-01

    The filamentous fungi Aspergillus parasiticus and A. flavus synthesize aflatoxins when they grow on a variety of susceptible food and feed crops. These mycotoxins are among the most carcinogenic naturally occurring compounds known and they pose significant health risks to humans and animals. We previously demonstrated that ethylene and CO2 act alone and together to reduce aflatoxin synthesis by A. parasiticus grown on laboratory media. To demonstrate the potential efficacy of treatment of stored seeds and grains with these gases, we tested ethylene and CO2 for ability to inhibit aflatoxin accumulation on Georgia Green peanuts stored for up to 5 days. We demonstrated an inverse relationship between A. parasiticus spore inoculum size and the level of toxin accumulation. We showed that ethylene inhibits aflatoxin synthesis in a dose-dependent manner on peanuts; CO2 also inhibits aflatoxin synthesis over a narrow dose range. Treatments had not discernable effect on mold growth. These observations support further exploration of this technology to reduce aflatoxin contamination of susceptible crops in the field and during storage. PMID:17418318

  19. Ethylene inhibits aflatoxin biosynthesis in Aspergillus parasiticus grown on peanuts.

    PubMed

    Gunterus, A; Roze, L V; Beaudry, R; Linz, J E

    2007-09-01

    The filamentous fungi Aspergillus parasiticus and Aspergillus flavus synthesize aflatoxins when they grow on a variety of susceptible food and feed crops. These mycotoxins are among the most carcinogenic naturally occurring compounds known and they pose significant health risks to humans and animals. We previously demonstrated that ethylene and CO2 act alone and together to reduce aflatoxin synthesis by A. parasiticus grown on laboratory media. To demonstrate the potential efficacy of treatment of stored seeds and grains with these gases, we tested ethylene and CO2 for ability to inhibit aflatoxin accumulation on Georgia Green peanuts stored for up to 5 days. We demonstrated an inverse relationship between A. parasiticus spore inoculum size and the level of toxin accumulation. We showed that ethylene inhibits aflatoxin synthesis in a dose-dependent manner on peanuts; CO2 also inhibits aflatoxin synthesis over a narrow dose range. Treatments had no discernable effect on mold growth. These observations support further exploration of this technology to reduce aflatoxin contamination of susceptible crops in the field and during storage.

  20. Potential natural exposure of endangered red-crowned crane (Grus japonensis) to mycotoxins aflatoxin B1, deoxynivalenol, zearalenone, T-2 toxin, and ochratoxin A*

    PubMed Central

    Liu, Da-wei; Liu, Hong-yi; Zhang, Hai-bin; Cao, Ming-chang; Sun, Yong; Wu, Wen-da; Lu, Chang-hu

    2016-01-01

    A survey was conducted to determine whether mycotoxins were present in the foods consumed by red-crowned cranes (Grus japonensis) in the Yancheng Biosphere Reserve, China. Collected in the reserve’s core, buffer, and experimental zones during overwintering periods of 2013 to 2015, a total of 113 food samples were analyzed for aflatoxin B1, deoxynivalenol, zearalenone, T-2 toxin, and ochratoxin A using high performance liquid chromatography (HPLC). The contamination incidences vary among different zones and the mycotoxins levels of different food samples also presented disparity. Average mycotoxin concentration from rice grain was greater than that from other food types. Among mycotoxin-positive samples, 59.3% were simultaneously contaminated with more than one toxin. This study demonstrated for the first time that red-crowned cranes were exposed to mycotoxins in the Yancheng Biosphere Reserve and suggested that artificial wetlands could not be considered good habitats for the birds in this reserve, especially rice fields. PMID:26834016

  1. Potential natural exposure of endangered red-crowned crane (Grus japonensis) to mycotoxins aflatoxin B1, deoxynivalenol, zearalenone, T-2 toxin, and ochratoxin A.

    PubMed

    Liu, Da-wei; Liu, Hong-yi; Zhang, Hai-bin; Cao, Ming-chang; Sun, Yong; Wu, Wen-da; Lu, Chang-hu

    2016-02-01

    A survey was conducted to determine whether mycotoxins were present in the foods consumed by red-crowned cranes (Grus japonensis) in the Yancheng Biosphere Reserve, China. Collected in the reserve's core, buffer, and experimental zones during overwintering periods of 2013 to 2015, a total of 113 food samples were analyzed for aflatoxin B1, deoxynivalenol, zearalenone, T-2 toxin, and ochratoxin A using high performance liquid chromatography (HPLC). The contamination incidences vary among different zones and the mycotoxins levels of different food samples also presented disparity. Average mycotoxin concentration from rice grain was greater than that from other food types. Among mycotoxin-positive samples, 59.3% were simultaneously contaminated with more than one toxin. This study demonstrated for the first time that red-crowned cranes were exposed to mycotoxins in the Yancheng Biosphere Reserve and suggested that artificial wetlands could not be considered good habitats for the birds in this reserve, especially rice fields.

  2. Primary Blast Exposure Increases Hippocampal Vulnerability to Subsequent Exposure: Reducing Long-Term Potentiation.

    PubMed

    Effgen, Gwen B; Ong, Tiffany; Nammalwar, Shruthi; Ortuño, Andrea I; Meaney, David F; 'Dale' Bass, Cameron R; Morrison, Barclay

    2016-10-15

    Up to 80% of injuries sustained by U.S. soldiers in Operation Enduring Freedom and Operation Iraqi Freedom were the result of blast exposure from improvised explosive devices. Some soldiers experience multiple blasts while on duty, and it has been suggested that symptoms of repetitive blast are similar to those that follow multiple non-blast concussions, such as sport-related concussion. Despite the interest in the effects of repetitive blast exposure, it remains unknown whether an initial blast renders the brain more vulnerable to subsequent exposure, resulting in a synergistic injury response. To investigate the effect of multiple primary blasts on the brain, organotypic hippocampal slice cultures were exposed to single or repetitive (two or three total) primary blasts of varying intensities. Long-term potentiation was significantly reduced following two Level 2 (92.7 kPa, 1.4 msec, 38.5 kPa·msec) blasts delivered 24 h apart without altering basal evoked response. This deficit persisted when the interval between injuries was increased to 72 h but not when the interval was extended to 144 h. The repeated blast exposure with a 24 h interval increased microglia staining and activation significantly but did not significantly increase cell death or damage axons, dendrites, or principal cell layers. Lack of overt structural damage and change in basal stimulated neuron response suggest that injury from repetitive primary blast exposure may specifically affect long-term potentiation. Our studies suggest repetitive primary blasts can exacerbate injury dependent on the injury severity and interval between exposures.

  3. Reducing youth exposure to alcohol ads: targeting public transit.

    PubMed

    Simon, Michele

    2008-07-01

    Underage drinking is a major public health problem. Youth drink more heavily than adults and are more vulnerable to the adverse effects of alcohol. Previous research has demonstrated the connection between alcohol advertising and underage drinking. Restricting outdoor advertising in general and transit ads in particular, represents an important opportunity to reduce youth exposure. To address this problem, the Marin Institute, an alcohol industry watchdog group in Northern California, conducted a survey of alcohol ads on San Francisco bus shelters. The survey received sufficient media attention to lead the billboard company, CBS Outdoor, into taking down the ads. Marin Institute also surveyed the 25 largest transit agencies; results showed that 75 percent of responding agencies currently have policies that ban alcohol advertising. However, as the experience in San Francisco demonstrated, having a policy on paper does not necessarily mean it is being followed. Communities must be diligent in holding accountable government officials, the alcohol industry, and the media companies through which advertising occurs.

  4. The case for aflatoxins in the causal chain of gallbladder cancer.

    PubMed

    Foerster, Claudia; Koshiol, Jill; Guerrero, Ariel R; Kogan, Marcelo J; Ferreccio, Catterina

    2016-01-01

    Chronic aflatoxin exposure has long been related to hepatocellular carcinoma (HCC). Recently, its association with gallbladder cancer (GBC) was postulated. Here we present the data supporting this hypothesis in Chile, the country with the highest GBC mortality worldwide with age-standardized mortality rates (ASMR) of 10.3 in women and 5.04 in men. The highest GBC rates occur in Southern Chile (ASMR=18), characterized by: high Amerindian ancestry, associated with high bile acid synthesis and gallstones; high poverty and high cereal agriculture, both associated with aflatoxin exposure. Aflatoxins have been detected in imported and locally grown foods items. We estimated population dietary exposure ranging from 0.25 to 35.0 ng/kg-body weight/day. The only report on human exposure in Chile found significantly more aflatoxin biomarkers in GBC than in controls (Odds Ratio=13.0). The hypothesis of aflatoxin-GBC causal link in the Chilean population is supported by: genetically-determined rapid cholesterol excretion and high gallstones prevalence (49.4%); low prevalence of HCC (ASMR=4.9) and low HBV infection (0.15%) the main co-factor of aflatoxins in HCC risk. If the association between aflatoxins and GBC were confirmed, public health interventions based on food regulation could have a substantial public health impact.

  5. Diagrams Showing Actions for Reducing Exposures to Polychlorinated Biphenyls (PCBs) in Indoor Building Environments

    EPA Pesticide Factsheets

    This diagram compliments the document, PCBs in Building Materials: Q's & A's, on how exposure to PCBs can be assessed and reduced in school buildings. It describes actions for reducing exposures to PCBs in indoor school building environments.

  6. Effect of microwave heating during alkaline-cooking of aflatoxin contaminated maize.

    PubMed

    Pérez-Flores, G C; Moreno-Martínez, E; Méndez-Albores, A

    2011-03-01

    To evaluate the effectiveness of maize detoxification achieved with a modified tortilla-making process (MTMP), maize contaminated with aflatoxin B(1) (AFB(1)) and aflatoxin B(2) (AFB(2)) at levels of 22.46, 69.62, and 141.48 ng/g (AFB(1)+ AFB(2)) was processed into tortillas. Aflatoxin content was determined according to the 991.31 AOAC official method. Based on the results obtained with spiked samples (0.78 to 25 ng/g), the mean recovery was 92%, with a standard error of 1.2, and a coefficient variation value of 4.4%. The MTMP caused 68, 80, and an 84% decrease in aflatoxin content, respectively. Extract acidification (as occurs during digestion) prior to mycotoxin quantification caused some reformation of the aflatoxin structure in tortillas (up to 3%). According to these results, the MTMP seems to be safe for decontamination since a low percentage of the initial aflatoxin concentration can be reverted to the original fluorescent form upon acidification. The potential presence of aflatoxins in maize destined for human consumption is a serious problem to the Mexican food supply, as these toxic compounds may persist during the traditional alkaline-process for tortilla elaboration. Consequently, new detoxification procedures are needed that eliminate or at least minimize the aflatoxin risk, through lowering aflatoxin concentration in maize-based products. Under these considerations, the use of MTMP is recommended, since it has definite advantages including non-production of wastewater and reduced energy/time consumption.

  7. Automated Aflatoxin Analysis Using Inline Reusable Immunoaffinity Column Cleanup and LC-Fluorescence Detection.

    PubMed

    Rhemrev, Ria; Pazdanska, Monika; Marley, Elaine; Biselli, Scarlett; Staiger, Simone

    2015-01-01

    A novel reusable immunoaffinity cartridge containing monoclonal antibodies to aflatoxins coupled to a pressure resistant polymer has been developed. The cartridge is used in conjunction with a handling system inline to LC with fluorescence detection to provide fully automated aflatoxin analysis for routine monitoring of a variety of food matrixes. The handling system selects an immunoaffinity cartridge from a tray and automatically applies the sample extract. The cartridge is washed, then aflatoxins B1, B2, G1, and G2 are eluted and transferred inline to the LC system for quantitative analysis using fluorescence detection with postcolumn derivatization using a KOBRA® cell. Each immunoaffinity cartridge can be used up to 15 times without loss in performance, offering increased sample throughput and reduced costs compared to conventional manual sample preparation and cleanup. The system was validated in two independent laboratories using samples of peanuts and maize spiked at 2, 8, and 40 μg/kg total aflatoxins, and paprika, nutmeg, and dried figs spiked at 5, 20, and 100 μg/kg total aflatoxins. Recoveries exceeded 80% for both aflatoxin B1 and total aflatoxins. The between-day repeatability ranged from 2.1 to 9.6% for aflatoxin B1 for the six levels and five matrixes. Satisfactory Z-scores were obtained with this automated system when used for participation in proficiency testing (FAPAS®) for samples of chilli powder and hazelnut paste containing aflatoxins.

  8. Effects of various acids and salts on growth and aflatoxin production by Aspergillus flavus NRRL 3145.

    PubMed

    Uraih, N; Chipley, J R

    1976-01-01

    The effects of sodium chloride, sodium acetate, benzoic acid, sodium benzoate, malonic acid, and sodium malonate on growth and aflatoxin production by Aspergillus flavus were investigated in synthetic media. Sodium chloride at concentrations equivalent to or greater than 12 g/100 ml inhibited growth and aflatoxin production, while at 8 g or less/100 ml, growth and aflatoxin production were stimulated. At 2 g or less/100 ml, sodium acetate also stimulated growth and aflatoxin production, but reduction occurred with 4 g or more/100 ml. Malonic acid at 10, 20, 40, and 50 mM reduced growth and aflatoxin production (over 50%) while sodium malonate at similar concentrations but different pH values had the opposite effect. Benzoic acid (pH 3.9) and sodium benzoate (pH 5.0) at 0.4 g/100 ml completely inhibited growth and aflatoxin production. Examination of the effect of initial pH indicated that the extent of inhibitory action of malonic acid and sodium acetate was a function of initial pH. The inhibitory action of benzoic acid and sodium benzoate appeared to be a function of undissociated benzoic acid molecules. Aflatoxin reduction was usually accompanied by an unidentified orange pigment, while aflatoxin stimulation was accompanied by unidentified blue and green fluorescent spots but with lower Rf values that aflatoxins B1, G1, B2, and G2 standards.

  9. Effect of aluminosilicates and bentonite on aflatoxin-induced developmental toxicity in rat.

    PubMed

    Abdel-Wahhab, M A; Nada, S A; Amra, H A

    1999-01-01

    Numerous studies have established that aflatoxin is a potent developmental toxin in animals. Previous research has demonstrated that a phyllosilicate clay, hydrated sodium calcium aluminosilicate (HSCAS or Novasil), tightly binds and immobilizes aflatoxins in the gastrointestinal tract of animals and markedly reduces the bioavailability and toxicity of aflatoxin. Our objective in this study was to utilize the pregnant rat as an in vivo model to compare the potential of HSCAS and bentonite to prevent the developmental toxicity of aflatoxin. Aluminosilicates (HSCAS) and bentonite were added to the diet at a level of 0.5% (w/w) and fed to the pregnant rat throughout pregnancy (i.e. days 0-20). Test animals were fed an aflatoxin-contaminated diet (2.5 mg kg(-1) diet) with or without sorbents during gestation days 6-15. Evaluations of toxicity were performed on day 20. These included maternal (mortality, body weights, feed intake and litter weights), developmental (embryonic resorptions and fetal body weights) and biochemical (ALT, AST and AP) evaluations. Sorbents alone were not toxic and aflatoxin alone resulted in significant maternal and developmental toxicity. Animals treated with phyllosilicate (plus aflatoxin) were comparable to controls following evaluations for resorptions, live fetuses and fetal body weights, as well as biochemical parameters. While bentonite plus aflatoxin resulted in significant reduction in fetal body weight, none of the fetuses from HSCAS or bentonite plus aflatoxin-treated groups had any gross, internal soft tissue or major skeletal malformations.

  10. Atoxigenic Aspergillus flavus endemic to Italy for biocontrol of aflatoxins in maize

    USDA-ARS?s Scientific Manuscript database

    Effective biological control of aflatoxin­producing Aspergillus flavus with atoxigenic members of that species requires suitable A. flavus well adapted to and resident in target agroecosystems. Eighteen atoxigenic isolates of A. flavus endemic in Italy were compared for ability to reduce aflatoxin c...

  11. Genome-Wide Association Mapping of and Aspergillus flavus Aflatoxin Accumulation Resistance in Maize

    Treesearch

    Marilyn L. Warburton; Juliet D. Tang; Gary L. Windham; Leigh K. Hawkins; Seth C. Murray; Wenwei Xu; Debbie Boykin; Andy Perkins; W. Paul Williams

    2015-01-01

    Contamination of maize (Zea mays L.) with aflatoxin, produced by the fungus Aspergillus flavus Link, has severe health and economic consequences. Efforts to reduce aflatoxin accumulation in maize have focused on identifying and selecting germplasm with natural host resistance factors, and several maize lines with significantly...

  12. Characterization of the maize lipoxygenase gene family in relation to aflatoxin accumulation resistance

    Treesearch

    Oluwaseun F. Ogunola; Leigh K. Hawkins; Erik Mylroie; Michael V. Kolomiets; Eli Borrego; Juliet D. Tang; Paul W. Williams; Marilyn L. Warburton

    2017-01-01

    Maize (Zea mays L.) is a globally important staple food crop prone to contamination by aflatoxin, a carcinogenic secondary metabolite produced by the fungus Aspergillus flavus. An efficient approach to reduce accumulation of aflatoxin is the development of germplasm resistant to colonization and toxin...

  13. Integrated process for ammonia inactivation of aflatoxin-contaminated corn and ethanol fermentation

    SciTech Connect

    Bothast, R.J.; Nofsinger, G.W.; Lagoda, A.A.; Black, L.T.

    1982-04-01

    A process is described for converting aflatoxin-contaminated corn to ethanol via combining ammonia inactivation with the liquefaction step of the ethanol fermentation process. Better ethanol yields were obtained when ammonia was added during liquefaction than when no ammonia was added. Aflatoxin B/sub 1/ levels were reduced 80 to 85% by the process.

  14. Genome wide association mapping of Aspergillus flavus and aflatoxin accumulation resistance in maize

    USDA-ARS?s Scientific Manuscript database

    Contamination of maize with aflatoxin, produced by the fungus Aspergillus flavus, has severe health and economic consequences. Efforts to reduce aflatoxin accumulation in maize have focused on identifying and selecting germplasm with natural host resistance factors, and several maize lines with sign...

  15. Further Studies on the Toxicity of the Aflatoxins on Human Cell Cultures

    PubMed Central

    Sullman, Susan F.; Armstrong, Sylvia J.; Zuckerman, A. J.; Rees, K. R.

    1970-01-01

    The cytotoxicity of aflatoxins G2 and B2 to cultured human embryo liver cells and of aflatoxin B1 to cultured adult liver cells, to cells of a semicontinuous diploid liver cell line and to a diploid lung cell line have been determined. Aflatoxins B2 and G2 were found to be considerably less toxic to human embryo liver cells than aflatoxin B1 and the LD50's were 35 and 10 μg./ml. respectively after 48 hr exposure to the toxin. Human adult liver cells in culture, cells of the liver cell line and lung cells were much less sensitive to the action of aflatoxin B1 than embryo liver cells. These results have been compared with those previously reported for B1 and G1 and the reasons for the variation in toxicity observed are discussed. PMID:5429074

  16. Potential reduced exposure products (PREPs) in industry trial testimony.

    PubMed

    Wayne, Geoffrey Ferris

    2006-12-01

    To identify patterns in trial testimony that may reflect on the intentions or expectations of tobacco manufacturers with regard to the introduction of potential reduced exposure products (PREPs). Research was conducted using the Deposition and Trial Testimony Archive (DATTA) collection of trial testimony and depositions housed online at Tobacco Documents Online (www.tobaccodocuments.org). Relevant testimony was identified through full-text searches of terms indicating PREPs or harm reduction strategies. The role and function of PREPs in testimony were classified according to common and contrasting themes. These were analysed in the context of broader trial arguments and against changes in time period and the market. Analysis of testimony suggests that the failure of PREPs in the market tempered initial industry enthusiasm and made protection of the conventional cigarette market its major priority. The "breakthrough" character of PREPs has been de-emphasised, with trial arguments instead positioning PREPs as simply another choice for consumers. This framework legitimises the sale of conventional brands, and shifts the responsibility for adoption of safer products from the manufacturer to the consumer. Likewise, testimony has abandoned earlier dramatic health claims made with regard to PREPs, which had undermined industry arguments regarding efforts to reduce harm in conventional products. More recent testimony advocates the broad acceptance of independent guidelines that would validate use of health claims and enable the industry to market PREPs to consumers. Trial testimony reflects the changing role and positioning of PREPs by the tobacco industry. The findings are of particular importance with regard to future evaluation and potential regulation of reduced harm products.

  17. Reduced autonomic activity during stepwise exposure to high altitude.

    PubMed

    Sevre, K; Bendz, B; Hankø, E; Nakstad, A R; Hauge, A; Kåsin, J I; Lefrandt, J D; Smit, A J; Eide, I; Rostrup, M

    2001-12-01

    Several studies have shown increased sympathetic activity during acute exposure to hypobaric hypoxia. In a recent field study we found reduced plasma catecholamines during the first days after a stepwise ascent to high altitude. In the present study 14 subjects were exposed to a simulated ascent in a hypobaric chamber to test the hypothesis of a temporary reduction in autonomic activity. The altitude was increased stepwise to 4500 m over 3 days. Heart rate variability (HRV) was assessed continuously in seven subjects. Baroreceptor reflex sensitivity (BRS) was determined in eight subjects with the 'Transfer Function' method at baseline, at 4500 m and after returning to baseline. Resting plasma catecholamines and cardiovascular- and plasma catecholamine- responses to cold pressor- (CPT) and mental stress-test (MST) were assessed daily in all and 12 subjects, respectively. Data are mean +/- SEM. Compared with baseline at 4500 m there were lower total power (TP) (35 457 +/- 26 302 vs. 15 001 +/- 11 176 ms2), low frequency (LF) power (3112 +/- 809 vs. 1741 +/- 604 ms2), high frequency (HF) power (1466 +/- 520 vs. 459 +/- 189 ms2) and HF normalized units (46 +/- 0.007 vs. 44 +/- 0.006%), P < or = 0.001. Baroreceptor reflex sensitivity decreased (15.6 +/- 2.1 vs. 9.5 +/- 2.6 ms mmHg(-1), P = 0.015). Resting noradrenaline (NA) decreased (522 +/- 98 vs. 357 +/- 60 pmol L(-1), P = 0.027). The increase in systolic blood pressure (SBP) and NA during mental stress was less pronounced (21 +/- 4 vs. 10 +/- 2% and 25 +/- 9 vs. -2 +/- 8%, respectively, P < 0.05). The increase in SBP during cold pressor test decreased (16 +/- 3 vs. 1 +/- 6%, P = 0.03). Diastolic blood pressure, HR and adrenaline displayed similar tendencies. We conclude that a transient reduction in parasympathetic and sympathetic activity was demonstrated during stepwise exposure to high altitude.

  18. Reducing workers' dust exposure during bag stacking in enclosed vehicles.

    PubMed

    Cecala, A B; Covelli, A; Thimons, E D

    1989-02-01

    The Bureau of Mines has evaluated cost effective systems to ventilate enclosed vehicles being loaded directly with bagged product material at mineral processing plants. This evaluation included both forms of transportation: railcars and trailer trucks. The goal of this research was to lower the dust exposure of workers stacking bags in these enclosed vehicles; these workers usually have the highest dust exposures in the entire processing plant. The problem occurs because there is no mechanical ventilation inside these vehicles. As the vehicle is being loaded, dust concentrations increase to substantial levels because released dust has no means of exiting the vehicle or of being diluted with fresh air. In cases where the dust is hazardous, as with silica sand, this may present a serious health hazard. This research project was a two-step effort. The first step was a qualitative laboratory evaluation performed in a railcar to compare different types of ventilation systems (blowing, exhaust, and push-pull systems) using a methane (CH4) tracer gas technique. An exhaust system located over the snake conveyor was the most effective system at reducing gas levels in and around the bag stacker's work area. The second step then involved a field evaluation at a silica sand processing plant to determine the system's effectiveness in the actual work environment. Three different versions were evaluated in an attempt to optimize the exhaust ventilation system's effectiveness. The most effective version involved exhausting 54.5 m3/min (2000 ft3/min) through a fiberglass tube located 1.1 m past the end of the slinger at a 2.0-m height so as not to interfere with the bag stacker's job function.(ABSTRACT TRUNCATED AT 250 WORDS)

  19. Associations of serum aflatoxin B1-lysine adduct level with socio-demographic factors and aflatoxins intake from nuts and related nut products in Malaysia.

    PubMed

    Leong, Yin-Hui; Rosma, Ahmad; Latiff, Aishah A; Izzah, A Nurul

    2012-04-01

    Aflatoxins are one of the major risk factors in the multi-factorial etiology of human hepatocellular carcinoma. Therefore, the information on aflatoxins exposure is very important in the intervention planning in order to reduce the dietary intake of aflatoxins, especially among the children. This study investigated the relationship between aflatoxin B(1) (AFB(1)) lysine adduct levers in serum and socio-demographic factors and dietary intake of aflatoxins from nuts and nut products in Penang, Malaysia. A cross-sectional field study was conducted in five districts of Penang. A survey on socio-demographic characteristics was administered to 364 healthy adults from the three main ethnic groups (Malay, Chinese and Indian). A total of 170 blood samples were successfully collected and tested for the level of AFB(1)-lysine adduct. 97% of the samples contained AFB(1)-lysine adduct above the detection limit of 0.4 pg/mg albumin and ranged from 0.20 to 23.16 pg/mg albumin (mean±standard deviation=7.67±4.54 pg/mg albumin; median=7.12 pg/mg albumin). There was no significant association between AFB(1)-lysine adduct levels with gender, district, education level, household number and occupation when these socio-demographic characteristics were examined according to high or low levels of AFB(1)-lysine. However, participants in the age group of 31-50 years were 3.08 times more likely to have high AFB(1) levels compared to those aged between 18 and 30 years (P=0.026). Significant difference (P=0.000) was found among different ethnic groups. Chinese and Indian participants were 3.05 and 2.35 times more likely to have high AFB(1) levels than Malay. The result of AFB(1)-lysine adduct suggested that Penang adult population is likely to be exposed to AFB(1) but at a level of less than that needed to cause direct acute illness or death.

  20. 7 CFR 983.4 - Aflatoxin.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Aflatoxin. 983.4 Section 983.4 Agriculture Regulations... NEW MEXICO Definitions § 983.4 Aflatoxin. Aflatoxin is one of a group of mycotoxins produced by the molds Aspergillus flavus and Aspergillus parasiticus. Aflatoxins are naturally occurring compounds...

  1. 7 CFR 983.4 - Aflatoxin.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Aflatoxin. 983.4 Section 983.4 Agriculture Regulations... NEW MEXICO Definitions § 983.4 Aflatoxin. Aflatoxin is one of a group of mycotoxins produced by the molds Aspergillus flavus and Aspergillus parasiticus. Aflatoxins are naturally occurring compounds...

  2. 7 CFR 983.4 - Aflatoxin.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Aflatoxin. 983.4 Section 983.4 Agriculture Regulations... NEW MEXICO Definitions § 983.4 Aflatoxin. Aflatoxin is one of a group of mycotoxins produced by the molds Aspergillus flavus and Aspergillus parasiticus. Aflatoxins are naturally occurring...

  3. 7 CFR 983.4 - Aflatoxin.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Aflatoxin. 983.4 Section 983.4 Agriculture Regulations... NEW MEXICO Definitions § 983.4 Aflatoxin. Aflatoxin is one of a group of mycotoxins produced by the molds Aspergillus flavus and Aspergillus parasiticus. Aflatoxins are naturally occurring...

  4. 7 CFR 983.4 - Aflatoxin.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Aflatoxin. 983.4 Section 983.4 Agriculture Regulations... NEW MEXICO Definitions § 983.4 Aflatoxin. Aflatoxin is one of a group of mycotoxins produced by the molds Aspergillus flavus and Aspergillus parasiticus. Aflatoxins are naturally occurring...

  5. A comparative study of the effect of aflatoxin B1 and actinomycin D on HeLa cells

    PubMed Central

    Harley, E. H.; Rees, K. R.; Cohen, A.

    1969-01-01

    1. The cytotoxic effects of aflatoxin B1 on HeLa cells were examined and effects of short exposures of the cells to the toxin were found to be reversible. 2. Aflatoxin B1 inhibited the synthesis of both ribosomal and heterodisperse RNA. It is proposed that the toxin's mechanism of action on ribosomal RNA synthesis is related to its inhibitory effect on the maturation of the 45s-ribosomal-RNA precursor. 3. Protein synthesis is inhibited to a greater extent by aflatoxin B1 than by actinomycin D. In contrast with actinomycin D, aflatoxin B1 was shown to disaggregate polyribosomes directly. ImagesPLATE 1PLATE 2 PMID:4897460

  6. Alleviation of Aflatoxin B1-Induced Genomic Damage by Proanthocyanidins via Modulation of DNA Repair.

    PubMed

    Bakheet, Saleh A; Alhuraishi, Ahmed M; Al-Harbi, Naif O; Al-Hosaini, Khaled A; Al-Sharary, Shakir D; Attia, Mohammed M; Alhoshani, Ali R; Al-Shabanah, Othman A; Al-Harbi, Mohammed M; Imam, Faisal; Ahmad, Sheikh F; Attia, Sabry M

    2016-11-01

    In order to study the mechanisms underlying the alleviation of aflatoxin B1-induced genomic damage by proanthocyanidins (PAs), we examined the modulation of oxidative DNA damage induced by aflatoxin B1 in PAs-pretreated animals. The effects of PAs on changes in the expression of DNA damage and repair genes induced by aflatoxin B1 were also evaluated in rat marrow cells. Administration of PAs before aflatoxin B1 significantly mitigated aflatoxin B1-induced oxidative DNA damage in a dose-dependent manner. Aflatoxin B1 treatment induced significant alterations in the expression of specific DNA repair genes, and the pre-treatment of rats with PAs ameliorated the altered expression of these genes. Conclusively, PAs protect against aflatoxin B1-induced oxidative DNA damage in rats. These protective effects are attributed to the antioxidant effects of PA and enhanced DNA repair through modulation of DNA repair gene expression. Therefore, PAs are a promising chemoprotective agent for averting genotoxic risks associated with aflatoxin B1 exposure.

  7. Aflatoxin levels in common foods of South Western Uganda: a risk factor to hepatocellular carcinoma.

    PubMed

    Kitya, D; Bbosa, G S; Mulogo, E

    2010-07-01

    Prolonged exposure to aflatoxins by humans and animals leads to adverse effects to the various body systems of affected individuals including death. Studies have linked aflatoxins to hepatocellular carcinoma (HCC). In Uganda, HCC is observed to be on increase in communities of South-Western Uganda. A cross-sectional study was therefore conducted in five districts of the region and 90 various food samples were collected for total aflatoxin determination. They included ground nuts, cassava, millet, sorghum flour and eshabwe sauce. The aflatoxin levels were determined using Vicam aflatest method. The results were compared with acceptable European Union aflatoxin levels. Aflatoxin levels in the food samples ranged from 0 to 55 ppb with a mean total aflatoxin level of 15.7 +/- 4.9 ppb. Eshabwe sauce had the highest mean total aflatoxin levels (18.6 +/- 2.4 ppb). Traditional methods of food processing in this study were found to be contributing risk factor of food contamination and hence the observed increased HCC cases and mortalities in the region.

  8. Aflatoxin B1 reduces non-enzymatic antioxidant defenses and increases protein kinase C activation in the cerebral cortex of young rats.

    PubMed

    Souto, Naiéli Schiefelbein; Claudia Monteiro Braga, Ana; Lutchemeyer de Freitas, Mayara; Rechia Fighera, Michele; Royes, Luiz Fernando Freire; Schneider Oliveira, Mauro; Furian, Ana Flávia

    2017-01-24

    Aflatoxin B1 (AFB1) is the most widespread mycotoxin, and it is a feed contaminant and is highly toxic, causing carcinogenic, mutagenic, and teratogenic effects. Many researches clarified the peripheral effects of the exposition to AFB1; however, there are few studies explaining their effects on central nervous system. The aim of the present study was to evaluate the effects caused by acute oral administration of AFB1 on behavioral tests and selected biochemical parameters. Young male Wistar rats received a single administration of AFB1 (250 µg/kg/i.g.) and 48 hours thereafter they were subjected to behavioral analysis. After the tests, biochemical parameters were measured in the cerebral cortex. Acute treatment with AFB1 caused neurotoxic effects, evidenced by a significant reduction in the levels of non-enzymatic antioxidant defenses, ascorbic acid, and non-protein sulfhydryl groups. In addition, AFB1 increased protein kinase C (PKC) activation, evidenced by an increase in phosphorylation of Ser(957) of PKCα. In this acute protocol, a single oral administration of AFB1 was able to cause changes in important neurochemical parameters, without concomitant, detectable behavioral alterations. These results reinforce that monitoring mycotoxin levels in food is essential to guarantee food security.

  9. [Determination of aflatoxins in cheeses].

    PubMed

    Bartos, J; Matyás, Z

    1979-03-01

    To investigate cheeses for the presence of aflatoxins we chose the very sensitive method of Tuinstra and Bronsgeest (1975) used for the determination of aflatoxin M1 in milk. The method was slightly modified and the presence of aflatoxins was determined in 54 samples of different cheeses. Aflatoxin M1 was found out in 24% of the investigated samples. Most of positive samples were found among the soft cheeses (53.8 3/4), then in processed cheeses (13.6%) and in hard cheeses (12.5%). Aflatoxin M1 was not found in the group of mouldy cheeses and Olomouc cake cheeses, which were investigated in a smaller range. Positive findings did not exceed concentrations of 10 ng per kg, i.e. they did not even reach the value of permissible concentration as proposed in the Czech Socialist Republic for foods (5 microgram per kg).

  10. Smokeless tobacco brand switching: a means to reduce toxicant exposure?

    PubMed

    Hatsukami, D K; Ebbert, J O; Anderson, A; Lin, H; Le, C; Hecht, S S

    2007-03-16

    The purpose of this study was to examine the effects of smokeless tobacco (ST) brand switching on biomarkers of ST exposure and on ST use. Subjects seeking treatment to reduce their use were randomized to ST brand switching with controlled ST topography, brand switching with ad libitum ST use, or a waitlist control with subsequent randomization to one of these two conditions. The waitlist control group was included to assess whether changes were a consequence of time effect. During the intervention, Copenhagen or Kodiak ST users were asked to switch to products that were sequentially lower in nicotine content: Skoal Long Cut Straight or Wintergreen for 4 weeks and then Skoal Bandits for the subsequent 4 weeks. Measures were obtained during the course of treatment and at 12-week follow-up. Significant reductions in total urinary cotinine and 4-(methylnitrosamino)-L-(3-pyridyl)-L-butanol (NNAL) plus its glucuronides (total NNAL) were observed with no significant differences between the controlled topography and ad libitum conditions. Significant reductions were also observed in the amount and duration of dips with a significant intervention effect for durational measures. At 12 weeks, the 7-day biochemically-verified tobacco abstinent rate was 26% in the ad libitum group. ST brand switching may be a feasible alternative intervention for ST users interested in quitting but unwilling to stop ST use completely.

  11. Reducing Youth Exposure to Alcohol Ads: Targeting Public Transit

    PubMed Central

    2008-01-01

    Underage drinking is a major public health problem. Youth drink more heavily than adults and are more vulnerable to the adverse effects of alcohol. Previous research has demonstrated the connection between alcohol advertising and underage drinking. Restricting outdoor advertising in general and transit ads in particular, represents an important opportunity to reduce youth exposure. To address this problem, the Marin Institute, an alcohol industry watchdog group in Northern California, conducted a survey of alcohol ads on San Francisco bus shelters. The survey received sufficient media attention to lead the billboard company, CBS Outdoor, into taking down the ads. Marin Institute also surveyed the 25 largest transit agencies; results showed that 75 percent of responding agencies currently have policies that ban alcohol advertising. However, as the experience in San Francisco demonstrated, having a policy on paper does not necessarily mean it is being followed. Communities must be diligent in holding accountable government officials, the alcohol industry, and the media companies through which advertising occurs. PMID:18389374

  12. Smokeless tobacco brand switching: A means to reduce toxicant exposure?

    PubMed Central

    Hatsukami, D.K.; Ebbert, J.O.; Anderson, A.; Lin, H.; Le, C.; Hecht, S.S.

    2007-01-01

    The purpose of this study was to examine the effects of smokeless tobacco (ST) brand switching on biomarkers of ST exposure and on ST use. Subjects seeking treatment to reduce their use were randomized to ST brand switching with controlled ST topography, brand switching with ad libitum ST use, or a waitlist control with subsequent randomization to one of these two conditions. The waitlist control group was included to assess whether changes were a consequence of time effect. During the intervention, Copenhagen or Kodiak ST users were asked to switch to products that were sequentially lower in nicotine content: Skoal Long Cut Original or Wintergreen for 4 weeks and then Skoal Bandits for the subsequent 4 weeks. Measures were obtained during the course of treatment and at 12-week follow-up. Significant reductions in total urinary cotinine and 4-(methylnitrosamino)-l-(3 pyridyl) l-butanol (NNAL) plus its glucuronides (total NNAL) were observed with no significant differences between the controlled topography and ad libitum conditions. Significant reductions were also observed in the amount and duration of dips with a significant intervention effect for durational measures. At 12 weeks, the 7-day biochemically-verified tobacco abstinent rate was 26% in the ad libitum group. ST brand switching may be a feasible alternative intervention for ST users interested in quitting but unwilling to stop ST use completely. PMID:16996230

  13. Pure versus guided mirror exposure to reduce body dissatisfaction: a preliminary study with university women.

    PubMed

    Moreno-Domínguez, Silvia; Rodríguez-Ruiz, Sonia; Fernández-Santaella, M Carmen; Jansen, Anita; Tuschen-Caffier, Brunna

    2012-03-01

    While effectiveness of mirror exposure to reduce body dissatisfaction has been demonstrated, the exposure was almost always combined with other interventions. The aim of the study was to evaluate the effectiveness of a pure mirror exposure intervention compared with a guided mirror exposure (participants are guided to describe their body shape in a non-evaluative manner) and an imagery exposure intervention (participants are guided to describe their body through mental representation). Thirty-one women with high body dissatisfaction received five sessions of treatment under one of the three conditions. All interventions reduced body dissatisfaction, but only the mirror exposures successfully reduced the frequency of negative thoughts and feelings of ugliness. Pure mirror exposure was more effective than guided exposure for reducing body discomfort within and between sessions. Pure mirror exposure, based on the traditional extinction paradigm, led to strong emotional activation followed by a fast decrease in emotional reactivity. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Reduction of aflatoxins by Rhizopus oryzae and Trichoderma reesei.

    PubMed

    Hackbart, H C S; Machado, A R; Christ-Ribeiro, A; Prietto, L; Badiale-Furlong, E

    2014-08-01

    This study evaluated the ability of the microorganisms Rhizopus oryzae (CCT7560) and Trichoderma reesei (QM9414), producers of generally recognized as safe (GRAS) enzymes, to reduce the level of aflatoxins B1, B2, G1, G2, and M1. The variables considered to the screening were the initial number of spores in the inoculum and the culture time. The culture was conducted in contaminated 4 % potato dextrose agar (PDA) medium, and the residual mycotoxins were determined every 24 h by HPLC-FL. The fungus R. oryzae has reduced aflatoxins B1, B2, and G1 in the 96 h and aflatoxins M1 and G2 in the range of 120 h of culture by approximately 100 %. The fungus T. reesei has reduced aflatoxins B1, B2, and M1 in the 96 h and aflatoxin G1 in the range of 120 h of culture by approximately 100 %. The highest reduction occurred in the middle of R. oryzae culture.

  15. Aflatoxins, discolouration and insect damage in dried cowpea and pigeon pea in Malawi and the effectiveness of flotation/washing operation in eliminating the aflatoxins.

    PubMed

    Matumba, Limbikani; Singano, Lazarus; Pungulani, Lawrent; Mvula, Naomi; Matumba, Annie; Singano, Charles; Matita, Grey

    2017-05-01

    Aflatoxin contamination and biodeterioration were examined in 302 samples of dry cowpeas and pigeon peas that were randomly purchased from 9 districts of the Southern Region of Malawi during July and November 2015. Further, the impact of flotation/washing on aflatoxin levels on the pulses was elucidated. Aflatoxin analyses involved immunoaffinity column (IAC) clean-up and HPLC quantification with fluorescence detection (FLD) while legume biodeterioration assessments were done by visual inspection. Aflatoxins were frequently detected in cowpea (24%, max., 66 μg/kg) and pigeon pea (22%, max., 80 μg/kg) samples that were collected in the month of July. Lower aflatoxin incidence of 15% in cowpeas (max., 470 μg/kg) and 14% in pigeon peas (max., 377 μg/kg) was recorded in the November collection. Overall, aflatoxin levels were significantly higher in the pulses that were collected in November. However, there were no significant differences in the total aflatoxin (aflatoxin B1 (AFB1) + AFB2 + AFG1 + AFG2) levels between the two types of pulses. Remarkably, in 76.2% of the aflatoxin positive cowpea and in 41.7% of the aflatoxin positive pigeon pea samples, aflatoxin G1 concentration exceeded aflatoxin B1. Insect damage percentage averaged at 18.1 ± 18.2% (mean ± SD) in the cowpeas and 16.1 ± 19.4% in pigeon peas. Mean discolouration percentage (number of pulses) of the cowpeas and pigeon peas was found to be at 6.7 ± 4.9 and 8.7 ± 6.2%, respectively. Washing and discarding the buoyant fraction was highly efficient in reducing aflatoxin levels; only 5.2 ± 11.1% of the initial aflatoxin level was found in the cleaned samples. In conclusion, cowpeas and pigeon peas sold on the local market in Malawi may constitute a hazard especially if floatation/washing step is skipped.

  16. Evaluation of atoxigenic isolates of Aspergillus flavus as potential biocontrol agents for aflatoxin in maize.

    PubMed

    Atehnkeng, J; Ojiambo, P S; Ikotun, T; Sikora, R A; Cotty, P J; Bandyopadhyay, R

    2008-10-01

    Aflatoxin contamination resulting from maize infection by Aspergillus flavus is both an economic and a public health concern. Therefore, strategies for controlling aflatoxin contamination in maize are being investigated. The abilities of eleven naturally occurring atoxigenic isolates in Nigeria to reduce aflatoxin contamination in maize were evaluated in grain competition experiments and in field studies during the 2005 and 2006 growing seasons. Treatments consisted of inoculation of either grains in vials or ears at mid-silking stage in field plots, with the toxigenic isolate (La3228) or atoxigenic isolate alone and co-inoculation of each atoxigenic isolate and La3328. Aflatoxin B(1) + B(2) concentrations were significantly (p < 0.05) lower in the co-inoculation treatments compared with the treatment in which the aflatoxin-producing isolate La3228 was inoculated alone. Relative levels of aflatoxin B(1) + B(2) reduction ranged from 70.1% to 99.9%. Among the atoxigenics, two isolates from Lafia, La3279 and La3303, were most effective at reducing aflatoxin B(1) + B(2) concentrations in both laboratory and field trials. These two isolates have potential value as agents for the biocontrol of aflatoxin contamination in maize. Because these isolates are endemic to West Africa, they are both more likely than introduced isolates to be well adapted to West African environments and to meet regulatory concerns over their use throughout that region.

  17. Reduction of Aflatoxins in Apricot Kernels by Electronic and Manual Color Sorting

    PubMed Central

    Zivoli, Rosanna; Gambacorta, Lucia; Piemontese, Luca; Solfrizzo, Michele

    2016-01-01

    The efficacy of color sorting on reducing aflatoxin levels in shelled apricot kernels was assessed. Naturally-contaminated kernels were submitted to an electronic optical sorter or blanched, peeled, and manually sorted to visually identify and sort discolored kernels (dark and spotted) from healthy ones. The samples obtained from the two sorting approaches were ground, homogenized, and analysed by HPLC-FLD for their aflatoxin content. A mass balance approach was used to measure the distribution of aflatoxins in the collected fractions. Aflatoxin B1 and B2 were identified and quantitated in all collected fractions at levels ranging from 1.7 to 22,451.5 µg/kg of AFB1 + AFB2, whereas AFG1 and AFG2 were not detected. Excellent results were obtained by manual sorting of peeled kernels since the removal of discolored kernels (2.6%–19.9% of total peeled kernels) removed 97.3%–99.5% of total aflatoxins. The combination of peeling and visual/manual separation of discolored kernels is a feasible strategy to remove 97%–99% of aflatoxins accumulated in naturally-contaminated samples. Electronic optical sorter gave highly variable results since the amount of AFB1 + AFB2 measured in rejected fractions (15%–18% of total kernels) ranged from 13% to 59% of total aflatoxins. An improved immunoaffinity-based HPLC-FLD method having low limits of detection for the four aflatoxins (0.01–0.05 µg/kg) was developed and used to monitor the occurrence of aflatoxins in 47 commercial products containing apricot kernels and/or almonds commercialized in Italy. Low aflatoxin levels were found in 38% of the tested samples and ranged from 0.06 to 1.50 μg/kg for AFB1 and from 0.06 to 1.79 μg/kg for total aflatoxins. PMID:26797635

  18. Reduction of Aflatoxins in Apricot Kernels by Electronic and Manual Color Sorting.

    PubMed

    Zivoli, Rosanna; Gambacorta, Lucia; Piemontese, Luca; Solfrizzo, Michele

    2016-01-19

    The efficacy of color sorting on reducing aflatoxin levels in shelled apricot kernels was assessed. Naturally-contaminated kernels were submitted to an electronic optical sorter or blanched, peeled, and manually sorted to visually identify and sort discolored kernels (dark and spotted) from healthy ones. The samples obtained from the two sorting approaches were ground, homogenized, and analysed by HPLC-FLD for their aflatoxin content. A mass balance approach was used to measure the distribution of aflatoxins in the collected fractions. Aflatoxin B₁ and B₂ were identified and quantitated in all collected fractions at levels ranging from 1.7 to 22,451.5 µg/kg of AFB₁ + AFB₂, whereas AFG₁ and AFG₂ were not detected. Excellent results were obtained by manual sorting of peeled kernels since the removal of discolored kernels (2.6%-19.9% of total peeled kernels) removed 97.3%-99.5% of total aflatoxins. The combination of peeling and visual/manual separation of discolored kernels is a feasible strategy to remove 97%-99% of aflatoxins accumulated in naturally-contaminated samples. Electronic optical sorter gave highly variable results since the amount of AFB₁ + AFB₂ measured in rejected fractions (15%-18% of total kernels) ranged from 13% to 59% of total aflatoxins. An improved immunoaffinity-based HPLC-FLD method having low limits of detection for the four aflatoxins (0.01-0.05 µg/kg) was developed and used to monitor the occurrence of aflatoxins in 47 commercial products containing apricot kernels and/or almonds commercialized in Italy. Low aflatoxin levels were found in 38% of the tested samples and ranged from 0.06 to 1.50 μg/kg for AFB₁ and from 0.06 to 1.79 μg/kg for total aflatoxins.

  19. Marlboro UltraSmooth: a potentially reduced exposure cigarette?

    PubMed Central

    Laugesen, Murray; Fowles, Jefferson

    2006-01-01

    cardiovascular toxicants, compared with most regular brands. MUS was not a potentially reduced‐exposure product (PREP) under smoker‐realistic test conditions, and thus would not be expected to reduce overall harm. It is unrealistic to expect that even major design changes, as seen in MUS, or a regulatory framework to enforce such changes, could reduce cigarette smoking mortality risks to acceptable levels. PMID:17130370

  20. Assessment of aflatoxin exposure of laboratory worker during food contamination analyses. Assessment of the procedures adopted by an A.R.P.A.L. laboratory (Liguria Region Environmental Protection Agency).

    PubMed

    Traverso, A; Bassoli, Viviana; Cioè, A; Anselmo, Silvia; Ferro, Marta

    2010-01-01

    Aflatoxins are mycotoxins derived from foodstuffs colonized by fungal species of the genus Aspergillus; they are common food contaminants with immunosuppressive, mutagenic and carcinogenic activity. Aflatoxins are heat-resistant and are thus easily transmitted along the food chain. They are hepatotoxic and have the potential to induce hepatocellular carcinoma. Agri-food industry workers are thus at risk of ingestion as well as transmucosal absorption or inhalation of toxins released during product preparation or processing. To measure the levels of airborne mycotoxins, particularly aflatoxins, in a laboratory analysing imported foodstuffs for mycotoxin contamination. The protocol used to analyse a batch of shelled peanuts from Vietnam, especially the grinding phase, which is held to be at the highest risk ofgenerating airborne toxins, was assessed at the A.R.PA.L. laboratory (Liguria Region Environmental Protection Agency) of Genoa, Italy, which participates in a European aflatoxin monitoring project. Wet grinding was performed to avoid production of large amounts of dust. Comparison of airborne concentrations before and after grinding with legal thresholds disclosed that the analytical procedures involved negligible aflatoxin levels for operators (environmental burden 0.11 pg/ m3). Given the toxicity of aflatoxins, worker protection measures should be consistently adopted and enforced. Threshold limit values for working environments should be introduced besides the existing ones for public health.

  1. Susceptibility to aflatoxin contamination among maize landraces from Mexico.

    PubMed

    Ortega-Beltran, Alejandro; Guerrero-Herrera, Manuel D J; Ortega-Corona, Alejandro; Vidal-Martinez, Victor A; Cotty, Peter J

    2014-09-01

    Maize, the critical staple food for billions of people, was domesticated in Mexico about 9,000 YBP. Today, a great array of maize landraces (MLRs) across rural Mexico is harbored in a living library that has been passed among generations since before the establishment of the modern state. MLRs have been selected over hundreds of generations by ethnic groups for adaptation to diverse environmental settings. The genetic diversity of MLRs in Mexico is an outstanding resource for development of maize cultivars with beneficial traits. Maize is frequently contaminated with aflatoxins by Aspergillus flavus, and resistance to accumulation of these potent carcinogens has been sought for over three decades. However, MLRs from Mexico have not been evaluated as potential sources of resistance. Variation in susceptibility to both A. flavus reproduction and aflatoxin contamination was evaluated on viable maize kernels in laboratory experiments that included 74 MLR accessions collected from 2006 to 2008 in the central west and northwest regions of Mexico. Resistant and susceptible MLR accessions were detected in both regions. The most resistant accessions accumulated over 99 % less aflatoxin B1 than did the commercial hybrid control Pioneer P33B50. Accessions supporting lower aflatoxin accumulation also supported reduced A. flavus sporulation. Sporulation on the MLRs was positively correlated with aflatoxin accumulation (R = 0.5336, P < 0.0001), suggesting that resistance to fungal reproduction is associated with MLR aflatoxin resistance. Results of the current study indicate that MLRs from Mexico are potentially important sources of aflatoxin resistance that may contribute to the breeding of commercially acceptable and safe maize hybrids and/or open pollinated cultivars for human and animal consumption.

  2. Stability of aflatoxins in solution.

    PubMed

    Diaz, Gonzalo J; Cepeda, Sandra M; Martos, Perry A

    2012-01-01

    The stability of aflatoxins B1, B2, G1, and G2 was studied in solutions containing different concentrations of water, acetonitrile, and/or methanol, and in autosampler vials treated with nitric acid or silanized. When stored at room temperature (20 degrees C) for 24 h, aflatoxins G1 and G2 were stable only in solutions containing 100% organic solvent, whereas aflatoxins B1 and B2 were stable in solutions of methanol-water and acetonitrile-water at greater than 60 and 40% organic content, respectively. At 5 degrees C, aflatoxins G1 and G2 showed a significant decrease in concentration only when kept in less than 20% aqueous organic solvent. Significant loss of aflatoxins was realized in standard, commercially available amber type I borosilicate autosampler vials, but chemical etching of the vials with nitric acid or with silanization prevented aflatoxin degradation. These results indicate that aflatoxins are unstable in aqueous solutions and that this instability can be counteracted by the presence of at least 20% organic solvent and keeping the solutions at 5 degrees C or by the use of treated vials.

  3. Reducing exposure through the use of photographic and electronic surveillance

    SciTech Connect

    Clow, H.

    1987-01-01

    There is little doubt that one of the major issues facing the nuclear industry today is the reduction of occupational radiation exposure. Increasingly, regulatory and advisory bodies are demanding that utilities take an aggressive approach in the development and implementation of exposure reduction programs. At the Connecticut Yankee Nuclear Plant, the authors have adopted an innovative approach to the as-low-as-reasonably-achievable dilemma. By using electronic and photographic technologies, we have developed training and surveillance programs that have proven effective in minimizing worker exposure.

  4. Peanut allergen exposure through saliva: assessment and interventions to reduce exposure.

    PubMed

    Maloney, Jennifer M; Chapman, Martin D; Sicherer, Scott H

    2006-09-01

    Exposure to food allergens through saliva (kissing, utensils) can cause local and systemic allergic reactions. To determine the time course of peanut allergen (Ara h 1) persistence in saliva after ingestion of peanut butter and to evaluate mouth cleansing interventions to reduce salivary peanut allergen. Thirty-eight individuals ingested 2 tablespoons of peanut butter, and saliva was collected at various time points. At another time, samples were collected after 5 interventions (brushing teeth, brushing and rinsing, rinsing, waiting then brushing, waiting then chewing gum). Detection of Ara h 1 was performed by a monoclonal-based ELISA (detection limit, 15-20 ng/mL). Salivary Ara h 1 varied considerably immediately after ingestion, but included levels expected to invoke reactions (as much as 40 microg/mL). Most (87%) subjects with detectable peanut after a meal had undetectable levels by 1 hour with no interventions. None had detectable levels several hours later after a peanut-free lunch. This result indicates (95% confidence) that 90% would have undetectable Ara h 1 in saliva under these circumstances. All of the interventions reduced salivary Ara h 1, in some cases by >95%, but Ara h 1 remained detectable in approximately 40% of samples (though typically below thresholds reported to induce reactions). Patients with peanut allergy require counseling regarding risks of kissing or sharing utensils, even if partners have brushed teeth or chewed gum. Advice to reduce risks, though not as ideal as total avoidance, includes waiting a few hours plus eating a peanut-free meal. Waiting several hours and ingesting a peanut-free meal were more effective at reducing salivary peanut protein concentration than simple, immediate interventions.

  5. 2013 Summit on Reducing Exposure to Dust from Treated Seed

    EPA Pesticide Factsheets

    The Pollinator Summit was part of EPA's ongoing collaboration with stakeholders to manage pesticide risks to bees. Focus: how to protect bees from unintended pesticide exposure, esp. dust in agricultural planting operations using pesticide-coated seeds.

  6. [Accumulation of aflatoxins on wheat grain inoculated by Aspergillus flavus NRRL 2999 and their distribution in grinding products].

    PubMed

    Lvova, L S; Sosedov, N I; Shatilova, T I; Shulgina, A P

    1975-01-01

    The influence of temperature ranging from 15 to 35 degrees C and relative humidity of 75 to 90% on the accumulation of aflatoxins on wheat grain inoculated by Aspergillus flavus NRRL 2999 was investigated. The lowest accumulation of aflatoxins took place at 20 degrees C and relative humidity of 80%. The highest accumulation of aflatoxins appeared in the grain after 3 day storage. Some products of three-graded 78% grinding showed a decrease in the aflatoxin content (flour of the first and second grade). During baking of leavened bread 70-80% of aflatoxins were decomposed. The feasible use of the rapid conditioning and Remix-method to reduce the content of aflatoxins in flour and bread is discussed.

  7. Development of Methods for Determination of Aflatoxins.

    PubMed

    Xie, Lijuan; Chen, Min; Ying, Yibin

    2016-12-09

    Aflatoxins can cause damage to the health of humans and animals. Several institutions around the world have established regulations to limit the levels of aflatoxins in food, and numerous analytical methods have been extensively developed for aflatoxin determination. This review covers the currently used analytical methods for the determination of aflatoxins in different food matrices, which includes sampling and sample preparation, sample pretreatment methods including extraction methods and purification methods of aflatoxin extracts, separation and determination methods. Validation for analysis of aflatoxins and safety considerations and precautions when doing the experiments are also discussed.

  8. Digital methods for reducing radiation exposure during medical fluoroscopy

    NASA Astrophysics Data System (ADS)

    Edmonds, Ernest W.; Rowlands, John A.; Hynes, David M.; Toth, B. D.; Porter, Anthony J.

    1990-07-01

    There is increased concern over radiation exposure to the general population from many sources. One of the most significant sources is that received by the patient during medical diagnostic procedures, and of these, the procedure with the greatest potential hazard is fluoroscopy. The legal limit for fluoroscopy in most jurisdictions is SR per minute skin exposure rate. Fluoroscopes are often operated in excess of this figure, and in the case of interventional procedures, fluorocopy times may exceed 20 minutes. With improvements in medical technology these procedures are being performed more often, and also are being carried out on younger age groups. Radiation exposure during fluoroscopy, both to patient and operator, is therefore becoming a matter of increasing concern to regulating authorities, and it is incumbent on us to develop digital technology to minimise the radiation hazard in these procedures. This paper explores the technical options available for radiation exposure reduction, including pulsed fluoroscopy, digital noise reduction, or simple reduction in exposure rate to the x-ray image intensifier. We also discuss educational aspects of fluoroscopy which radiologists should be aware of which can be more important than the technological solutions. A "work in progress" report gives a completely new approach to the implementation of a large number of possible digital algorithms, for the investigation of clinical efficacy.

  9. Population structure and aflatoxin production by Aspergillus Sect. Flavi from maize in Nigeria and Ghana.

    PubMed

    Perrone, Giancarlo; Haidukowski, Miriam; Stea, Gaetano; Epifani, Filomena; Bandyopadhyay, Ranajit; Leslie, John F; Logrieco, Antonio

    2014-08-01

    Aflatoxins are highly toxic carcinogens that contaminate crops worldwide. Previous studies conducted in Nigeria and Ghana found high concentrations of aflatoxins in pre- and post-harvest maize. However, little information is available on the population structure of Aspergillus Sect. Flavi in West Africa. We determined the incidence of Aspergillus Sect. Flavi and the level of aflatoxin contamination in 91 maize samples from farms and markets in Nigeria and Ghana. Aspergillus spp. were recovered from 61/91 maize samples and aflatoxins B1 and/or B2 occurred in 36/91 samples. Three samples from the farms also contained aflatoxin G1 and/or G2. Farm samples were more highly contaminated than were samples from the market, in terms of both the percentage of the samples contaminated and the level of mycotoxin contamination. One-hundred-and-thirty-five strains representative of the 1163 strains collected were identified by using a multilocus sequence analysis of portions of the genes encoding calmodulin, β-tubulin and actin, and evaluated for aflatoxin production. Of the 135 strains, there were 110 - Aspergillus flavus, 20 - Aspergillus tamarii, 2 - Aspergillus wentii, 2 - Aspergillus flavofurcatus, and 1 - Aspergillus parvisclerotigenus. Twenty-five of the A. flavus strains and the A. parvisclerotigenus strain were the only strains that produced aflatoxins. The higher contamination of the farm than the market samples suggests that the aflatoxin exposure of rural farmers is even higher than previously estimated based on reported contamination of market samples. The relative infrequency of the A. flavus SBG strains, producing small sclerotia and high levels of both aflatoxins (B and G), suggests that long-term chronic exposure to this mycotoxin are a much higher health risk in West Africa than is the acute toxicity due to very highly contaminated maize in east Africa.

  10. Isolation of methyl syringate as a specific aflatoxin production inhibitor from the essential oil of Betula alba and aflatoxin production inhibitory activities of its related compounds.

    PubMed

    Jermnak, Usuma; Yoshinari, Tomoya; Sugiyama, Yasumasa; Tsuyuki, Rie; Nagasawa, Hiromichi; Sakuda, Shohei

    2012-02-15

    Methyl syringate was isolated from the essential oil of Betula alba as an aflatoxin production inhibitor. It inhibited aflatoxin production of Aspergillus parasiticus and Aspergillus flavus with IC(50) values of 0.9 and 0.8 mM, respectively, without significantly inhibiting fungal growth. Methyl syringate reduced mRNA levels of genes (aflR, pksA, and omtB) [corrected] encoding proteins required for aflatoxin biosynthesis. Methyl gallate, methyl 3,4,5-trimethoxybenzoate, and methyl 3-O-methylgallate inhibited both aflatoxin production and fungal growth of A. parasiticus and A. flavus. However, their acids and syringic acid did not inhibit aflatoxin production and growth of A. parasiticus significantly, although gallic acid inhibited aflatoxin production of A. flavus with selectivity. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity of methyl syringate was much weaker than that of gallic acid. These results showed that methyl syringate has a unique inhibitory activity toward aflatoxin production with a different mode of action from that of gallic acid.

  11. Effects of Bacillus subtilis ANSB060 on growth performance, meat quality and aflatoxin residues in broilers fed moldy peanut meal naturally contaminated with aflatoxins.

    PubMed

    Fan, Yu; Zhao, Lihong; Ma, Qiugang; Li, Xiaoying; Shi, Huiqin; Zhou, Ting; Zhang, Jianyun; Ji, Cheng

    2013-09-01

    This study was conducted to investigate the toxic effects of aflatoxins and the efficacy of Bacillus subtilis ANSB060 for the amelioration of aflatoxicosis in broiler chickens. Six replicates of ten broilers each were assigned to one of seven dietary treatments, which were labeled C0 (basal diet); M0 (basal diet containing moldy peanut meal); C500 and C1000 (C0+500 or 1000 g/t aflatoxin biodegradation preparations, composed mainly of ANSB060); and M500, M1000 and M2000 (M0+500, 1000 or 2000 g/t aflatoxin biodegradation preparations). The concentrations of aflatoxin B₁, B₂, G₁ and G₂ in the moldy diets (M0, M500, M100 and M2000) fluctuated around 70.7±1.3, 11.0±1.5, 6.5±0.8 and 2.0±0.3 μg/kg, respectively. The results showed that the M0 diet caused a significant decrease in average daily weight gain and increased feed requirements, with a gain ratio increasing from d 8 to 42, deterioration in meat quality and aflatoxin residues in broilers' livers as compared with the C0 diet. The addition of ANSB060 to the aflatoxin-contaminated diets offset these negative effects, leading to the conclusion that ANSB060 has a protective effect on growth performance and meat quality while reducing the amount of aflatoxin residues in the livers of broilers fed naturally moldy peanut meal.

  12. Reduce Toxic Exposures: Get Involved and Take Action!

    ERIC Educational Resources Information Center

    Exceptional Parent, 2006

    2006-01-01

    There is a growing concern about the connection between many chemical exposures and learning and other developmental disabilities (LDD). National and local groups are developing new programs around the country that are making this connection--and taking action with regard to policy, education and research efforts. They are working towards reducing…

  13. Fetal Alcohol Exposure Reduces Adult Brain Plasticity. Science Briefs

    ERIC Educational Resources Information Center

    National Scientific Council on the Developing Child, 2007

    2007-01-01

    "Science Briefs" summarize the findings and implications of a recent study in basic science or clinical research. This Brief summarizes the findings and implications of "Moderate Fetal Alcohol Exposure Impairs the Neurogenic Response to an Enriched Environment in Adult Mice" (I. Y. Choi; A. M. Allan; and L. A. Cunningham). Observations of mice…

  14. Fetal Alcohol Exposure Reduces Adult Brain Plasticity. Science Briefs

    ERIC Educational Resources Information Center

    National Scientific Council on the Developing Child, 2007

    2007-01-01

    "Science Briefs" summarize the findings and implications of a recent study in basic science or clinical research. This Brief summarizes the findings and implications of "Moderate Fetal Alcohol Exposure Impairs the Neurogenic Response to an Enriched Environment in Adult Mice" (I. Y. Choi; A. M. Allan; and L. A. Cunningham). Observations of mice…

  15. Reduce Toxic Exposures: Get Involved and Take Action!

    ERIC Educational Resources Information Center

    Exceptional Parent, 2006

    2006-01-01

    There is a growing concern about the connection between many chemical exposures and learning and other developmental disabilities (LDD). National and local groups are developing new programs around the country that are making this connection--and taking action with regard to policy, education and research efforts. They are working towards reducing…

  16. Malonate as a precursor in the biosynthesis of aflatoxins.

    PubMed

    Gupta, S R; Prasanna, H R; Viswanathan, L; Venkitasurbramanian, T A

    1975-06-01

    Incorporation of [I-14C]acetate and [2-14C]malonate into aflatoxins by resting mycelia of Aspergillus parasiticus resuspended in different buffers was studied. A decrease in pH from 5-8 to 2-8, as well as addition of EDTA, markedly stimulated the incorporation of malonate but the effect on acetate incorporation was less pronounced. Mycelia took up comparatively more acetate than malonate, but more malonate (4-3%) entering mycelia was incorporated into aflatoxins than was acetate (1-6%). Furthermore, the addition of unlabelled acetate reduced the incorporation of label from [I-14C]acetate by 75% but from [2-14C]malonate by only 25%. These results suggest that malonate is an intermediate in aflatoxin synthesis and that is can be incorporated without prior conversion to acetate.

  17. Global risk assessment of aflatoxins in maize and peanuts: are regulatory standards adequately protective?

    PubMed

    Wu, Felicia; Stacy, Shaina L; Kensler, Thomas W

    2013-09-01

    The aflatoxins are a group of fungal metabolites that contaminate a variety of staple crops, including maize and peanuts, and cause an array of acute and chronic human health effects. Aflatoxin B1 in particular is a potent liver carcinogen, and hepatocellular carcinoma (HCC) risk is multiplicatively higher for individuals exposed to both aflatoxin and chronic infection with hepatitis B virus (HBV). In this work, we sought to answer the question: do current aflatoxin regulatory standards around the world adequately protect human health? Depending upon the level of protection desired, the answer to this question varies. Currently, most nations have a maximum tolerable level of total aflatoxins in maize and peanuts ranging from 4 to 20ng/g. If the level of protection desired is that aflatoxin exposures would not increase lifetime HCC risk by more than 1 in 100,000 cases in the population, then most current regulatory standards are not adequately protective even if enforced, especially in low-income countries where large amounts of maize and peanuts are consumed and HBV prevalence is high. At the protection level of 1 in 10,000 lifetime HCC cases in the population, however, almost all aflatoxin regulations worldwide are adequately protective, with the exception of several nations in Africa and Latin America.

  18. Global Risk Assessment of Aflatoxins in Maize and Peanuts: Are Regulatory Standards Adequately Protective?

    PubMed Central

    Wu, Felicia

    2013-01-01

    The aflatoxins are a group of fungal metabolites that contaminate a variety of staple crops, including maize and peanuts, and cause an array of acute and chronic human health effects. Aflatoxin B1 in particular is a potent liver carcinogen, and hepatocellular carcinoma (HCC) risk is multiplicatively higher for individuals exposed to both aflatoxin and chronic infection with hepatitis B virus (HBV). In this work, we sought to answer the question: do current aflatoxin regulatory standards around the world adequately protect human health? Depending upon the level of protection desired, the answer to this question varies. Currently, most nations have a maximum tolerable level of total aflatoxins in maize and peanuts ranging from 4 to 20ng/g. If the level of protection desired is that aflatoxin exposures would not increase lifetime HCC risk by more than 1 in 100,000 cases in the population, then most current regulatory standards are not adequately protective even if enforced, especially in low-income countries where large amounts of maize and peanuts are consumed and HBV prevalence is high. At the protection level of 1 in 10,000 lifetime HCC cases in the population, however, almost all aflatoxin regulations worldwide are adequately protective, with the exception of several nations in Africa and Latin America. PMID:23761295

  19. Autoxidated linolenic acid inhibits aflatoxin biosynthesis in Aspergillus flavus via oxylipin species.

    PubMed

    Yan, Shijuan; Liang, Yating; Zhang, Jindan; Chen, Zhuang; Liu, Chun-Ming

    2015-08-01

    Aflatoxins produced by Aspergillus species are among the most toxic and carcinogenic compounds in nature. Although it has been known for a long time that seeds with high oil content are more susceptible to aflatoxin contamination, the role of fatty acids in aflatoxin biosynthesis remains controversial. Here we demonstrate in A. flavus that both the saturated stearic acid (C18:0) and the polyunsaturated linolenic acid (C18:3) promoted aflatoxin production, while C18:3, but not C18:0, inhibited aflatoxin biosynthesis after exposure to air for several hours. Further experiments showed that autoxidated C18:3 promoted mycelial growth, sporulation, and kojic acid production, but inhibited the expression of genes in the AF biosynthetic gene cluster. Mass spectrometry analyses of autoxidated C18:3 fractions that were able to inhibit aflatoxin biosynthesis led to the identification of multiple oxylipin species. These results may help to clarify the role of fatty acids in aflatoxin biosynthesis, and may explain why controversial results have been obtained for fatty acids in the past.

  20. Evening media exposure reduces night-time sleep.

    PubMed

    Vijakkhana, Nakul; Wilaisakditipakorn, Tanaporn; Ruedeekhajorn, Kitja; Pruksananonda, Chandhita; Chonchaiya, Weerasak

    2015-03-01

    To investigate whether evening media exposure, bedroom media use and night-time sleep duration at age 6 months are associated with night-time sleep duration in 12-month-old Thai infants. We enrolled 208 infants in this study at 6 months of age. They were followed-up at 12 months of age. A sleep diary was used to document the infant's sleep onset and wake time at each visit. Night-time sleep duration was then calculated at both ages. Screen media exposure in the household was assessed in depth at both visits. Infants who were exposed to screen media in the evening at 12 months of age had a 28-min decrease in 12-month night-time sleep duration on weekdays. Moreover, infants who were exposed to screen media in the evening at age 6 months and 12 months had shorter 12-month night-time sleep duration compared with those who were not exposed to screen media after 7 pm at both ages. Night-time sleep duration at 12 months of age was also directly related to 6-month night-time sleep duration. Infants exposed to screen media in the evening at 12 months of age had decreased 12-month night-time sleep duration. To promote good sleep hygiene and optimal sleep for infants at this age, screen media exposure after 7 pm should be avoided. ©2014 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

  1. Cytotoxicity of aflatoxin on red blood corpuscles

    SciTech Connect

    Verma, R.J.; Raval, P.J. )

    1991-09-01

    The exact mechanism of aflatoxin action is not clearly understood. In the present investigation the authors report morphological aberrations and increased rate of hemolysis caused by aflatoxins in vitro.

  2. Evaluation of Atoxigenic Strains of Aspergillus flavus as Potential Biocontrol Agents for Aflatoxin in Maize

    USDA-ARS?s Scientific Manuscript database

    Aflatoxin contamination resulting from maize infection by Aspergillus flavus is both an economic concern and public health concern. Therefore, strategies for controlling maize contamination are being investigated. Abilities of 11 naturally occurring atoxigenic strains in Nigeria to reduce aflatox...

  3. Aflatoxin in Tunisian aleppo pine nuts.

    PubMed

    Boutrif, E; Jemmali, M; Pohland, A E; Campbell, A D

    1977-05-01

    Twenty-six of 50 Aleppo pine nuts samples collected throughout Tunisia showed relatively high levels of contamination by aflatoxin. Some samples contained as much as 2000 ppb aflatoxin B1, and very few contained less than 100 ppb. Total aflatoxins as high as 7550 ppb were found. A traditional pudding, widely consumed in Tunisia, which was prepared from contaminated nuts still contained more than 80% of the aflatoxin originally present in the nuts.

  4. Molecular markers and strategies to control aflatoxin in peanut

    USDA-ARS?s Scientific Manuscript database

    Methods of isolation of molecular markers and software developed in ARS for finding the most informative markers will be presented. Also, two different approaches being used at the NPRL to reduce aflatoxin in peanut will be discussed. One is the development of phytoalexin-detoxification enzyme inh...

  5. A Novel Technique to Reduce Contrast Exposure During Subclavian Interventions.

    PubMed

    Sanon, Saurabh; Barsness, Gregory W; Gulati, Rajiv

    2017-02-01

    We describe a novel technique to minimize total body contrast exposure during endovascular angiography. A patient with severe renal impairment and history of contrast-induced nephropathy was referred for subclavian artery intervention. Angiography and intervention was performed via transfemoral access, while a transradial sheathless-guiding catheter was used to aspirate injected contrast/blood mix from the downstream axillary artery. Semiquantitative analysis indicated approximately 50% of the injected contrast was retrieved. Adaptation of this simple strategy could be considered for selected coronary, lower extremity, and carotid procedures, using contrast removal techniques from the coronary sinus, femoral, and jugular veins.

  6. ALARA study of teaching effectiveness on reducing radiation exposure.

    PubMed

    Feigenbaum, K; Ellett, M L; Miller, R; Hyland, L

    1998-01-01

    The purpose of this study was to measure the effectiveness of radiation safety instruction and the impact on radiation film badge levels. A convenience sample of 144 endoscopy nurses and technicians was pretested for radiation safety knowledge, given a course in radiation safety, and then posttested immediately after the course and then 6 months later. Radiation badges were analyzed for radiation exposure at preinstruction, 1 month postinstruction, and 6 months postinstruction. Results showed that the instruction was effective. There was only a slight decrease in radiation badge readings; the decrease, however, was not statistically significant.

  7. Aspergillus flavus: The Major Producer of Aflatoxin

    USDA-ARS?s Scientific Manuscript database

    Aspergillus flavus is an opportunistic pathogen of crops. It is important because it produces aflatoxin as a secondary metabolite in the seeds of a number of crops both before and after harvest. Aflatoxin is a potent carcinogen that is highly regulated in most countries. In the field, aflatoxin i...

  8. 7 CFR 983.50 - Aflatoxin regulations.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Aflatoxin regulations. 983.50 Section 983.50..., ARIZONA, AND NEW MEXICO Regulations § 983.50 Aflatoxin regulations. The committee shall establish, with the approval of the Secretary, such aflatoxin sampling, analysis, and inspection...

  9. 7 CFR 983.150 - Aflatoxin regulations.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Aflatoxin regulations. 983.150 Section 983.150..., ARIZONA, AND NEW MEXICO Rules and Regulations § 983.150 Aflatoxin regulations. (a) Maximum level. No handler shall ship for domestic human consumption, pistachios that exceed an aflatoxin level of 15...

  10. 7 CFR 983.50 - Aflatoxin regulations.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Aflatoxin regulations. 983.50 Section 983.50..., ARIZONA, AND NEW MEXICO Regulations § 983.50 Aflatoxin regulations. The committee shall establish, with the approval of the Secretary, such aflatoxin sampling, analysis, and inspection...

  11. 7 CFR 983.50 - Aflatoxin regulations.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Aflatoxin regulations. 983.50 Section 983.50..., ARIZONA, AND NEW MEXICO Regulations § 983.50 Aflatoxin regulations. The committee shall establish, with the approval of the Secretary, such aflatoxin sampling, analysis, and inspection...

  12. 7 CFR 983.150 - Aflatoxin regulations.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Aflatoxin regulations. 983.150 Section 983.150..., ARIZONA, AND NEW MEXICO Rules and Regulations § 983.150 Aflatoxin regulations. (a) Maximum level. No handler shall ship for domestic human consumption, pistachios that exceed an aflatoxin level of 15...

  13. 7 CFR 983.150 - Aflatoxin regulations.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Aflatoxin regulations. 983.150 Section 983.150..., ARIZONA, AND NEW MEXICO Rules and Regulations § 983.150 Aflatoxin regulations. (a) Maximum level. No handler shall ship for domestic human consumption, pistachios that exceed an aflatoxin level of 15...

  14. Molecular biomarkers for aflatoxins and their application to human liver cancer.

    PubMed

    Scholl, P; Musser, S M; Kensler, T W; Groopman, J D

    1995-01-01

    The rationale for developing molecular biomarkers to monitor and assess risk from human exposure to aflatoxins have been justified by the association of these carcinogens with human liver cancer, a disease that causes at least 250000 deaths world-wide each year. The goal of our research has been the development of aflatoxin biomarkers based upon the knowledge of the biochemistry and toxicology of aflatoxins gleaned from both experimental and human studies. These biomarkers have been subsequently utilized in experimental chemoprotection models to provide data on the modulation of these markers under different situations of disease risk. Several of the aflatoxin specific biomarkers have been validated in epidemiologic studies and are now available to use as intermediate biomarkers in chemoprotection trials. This systematic approach provides encouragement for preventive interventions and should serve as a template for the development, validation and application of other chemical-specific biomarkers to cancer or other chronic diseases.

  15. Detection of aflatoxin-contaminated grain by three granivorous bird species.

    PubMed

    Perez, M; Henke, S E; Fedynich, A M

    2001-04-01

    Supplemental feeding of game species and the use of backyard feeders to attract avian wildlife are common practices throughout the United States. However, these activities may expose wildlife to aflatoxins. We tested the hypothesis that wild birds would avoid consuming aflatoxin-contaminated feed. Individual northern bobwhites (Colinus virginianus), white-winged doves (Zenaida asiatica), and green jays (Cyanocorax yncas) were presented with feeders that had four compartments, which contained milo that was contaminated with aflatoxin levels of 0, 100, 500, and 1,000 microg/kg, respectively. Feed remaining was weighed at 6, 12, 18, 24, 36, 48, 60, and 72 hr after the initiation of the trial. White-winged doves and northern bobwhites did not avoid contaminated feed. However, green jays selected against aflatoxin-tainted grain. Because white-winged doves and northern bobwhites did not avoid contaminated feed, the risk of exposure to this potentially hazardous toxin exists for these species.

  16. Aflatoxins ingestion and canine mammary tumors: There is an association?

    PubMed

    Frehse, M S; Martins, M I M; Ono, E Y S; Bracarense, A P F R L; Bissoqui, L Y; Teixeira, E M K; Santos, N J R; Freire, R L

    2015-10-01

    The aim of this study was to determine the presence of mycotoxins on dogs feed and to explore the potential association between mycotoxins exposure and the chance of mamary tumors in a case-control study. The study included 256 female dogs from a hospital population, 85 with mammary tumors (case group) and 171 without mammary tumors (control group). An epidemiological questionnaire was applied to both groups, and the data were analyzed by the EpiInfo statistical package. For the study, 168 samples of the feed offered to dogs were analyzed for the presence of aflatoxins, fumonisins and zearalenone by high-performance liquid chromatography. Mycotoxins were found in 79 samples (100%) in the case group and 87/89 (97.8%) in the control group. Mycotoxins were detected in all types of feed, regardless feed quality. Level of aflatoxin B1 (p = 0.0356, OR = 2.74, 95%, CI 1.13 to 6.60), aflatoxin G1 (AFG1) (p = 0.00007, OR = 4.60, 95%, CI = 2.16 to 9.79), and aflatoxin G2 (AFG2) (p = 0.0133, OR = 9.91, 95%, CI 1.21 to 81.15) were statistically higher in case of mammary cancer. In contrast, neutering was a protective factor for mammary cancer (p = 0.0004, OR = 0.32, 95%, CI = 0.17 to 0.60).

  17. Role of American Nuclear Insurers in reducing occupational radiation exposure

    SciTech Connect

    Forbes, J.L.

    1980-01-01

    Since 1957 the nuclear insurance pools have provided liability and property insurance for the nation's nuclear power generating stations as mandated by the Price-Anderson Act. Although the insurance was originally structured to give financial protection to the insured in the event of a major accident, the potential for third-party claims arising from routine occupational exposure is becoming a more realistic pathway for a loss to the pools. In order to give maximum protection to the pools' assets, the Liability Engineering Department of American Nuclear Insurers (ANI) performs periodic inspections of the power plants. By concentrating on programs and management areas, ANI inspections complement regulatory inspections so that all major areas of common interest are reviewed. This paper presents the nature, results, and findings of those periodic inspections particularly in the general area of plant radiation protection.

  18. Use of Probiotics to Control Aflatoxin Production in Peanut Grains.

    PubMed

    da Silva, Juliana Fonseca Moreira; Peluzio, Joenes Mucci; Prado, Guilherme; Madeira, Jovita Eugênia Gazzinelli Cruz; Silva, Marize Oliveira; de Morais, Paula Benevides; Rosa, Carlos Augusto; Pimenta, Raphael Sanzio; Nicoli, Jacques Robert

    2015-01-01

    Probiotic microorganisms (Saccharomyces cerevisiae var. boulardii, S. cerevisiae UFMG 905, and Lactobacillus delbrueckii UFV H2b20) were evaluated as biological control agents to reduce aflatoxin and spore production by Aspergillus parasiticus IMI 242695 in peanut. Suspensions containing the probiotics alone or in combinations were tested by sprinkling on the grains followed by incubation for seven days at 25°C. All probiotic microorganisms, in live and inactivated forms, significantly reduced A. parasiticus sporulation, but the best results were obtained with live cells. The presence of probiotics also altered the color of A. parasiticus colonies but not the spore morphology. Reduction in aflatoxin production of 72.8 and 65.8% was observed for S. boulardii and S. cerevisiae, respectively, when inoculated alone. When inoculated in pairs, all probiotic combinations reduced significantly aflatoxin production, and the best reduction was obtained with S. boulardii plus L. delbrueckii (96.1%) followed by S. boulardii plus S. cerevisiae and L. delbrueckii plus S. cerevisiae (71.1 and 66.7%, resp.). All probiotics remained viable in high numbers on the grains even after 300 days. The results of the present study suggest a different use of probiotics as an alternative treatment to prevent aflatoxin production in peanut grains.

  19. Use of Probiotics to Control Aflatoxin Production in Peanut Grains

    PubMed Central

    da Silva, Juliana Fonseca Moreira; Peluzio, Joenes Mucci; Madeira, Jovita Eugênia Gazzinelli Cruz; Silva, Marize Oliveira; de Morais, Paula Benevides; Rosa, Carlos Augusto; Pimenta, Raphael Sanzio; Nicoli, Jacques Robert

    2015-01-01

    Probiotic microorganisms (Saccharomyces cerevisiae var. boulardii, S. cerevisiae UFMG 905, and Lactobacillus delbrueckii UFV H2b20) were evaluated as biological control agents to reduce aflatoxin and spore production by Aspergillus parasiticus IMI 242695 in peanut. Suspensions containing the probiotics alone or in combinations were tested by sprinkling on the grains followed by incubation for seven days at 25°C. All probiotic microorganisms, in live and inactivated forms, significantly reduced A. parasiticus sporulation, but the best results were obtained with live cells. The presence of probiotics also altered the color of A. parasiticus colonies but not the spore morphology. Reduction in aflatoxin production of 72.8 and 65.8% was observed for S. boulardii and S. cerevisiae, respectively, when inoculated alone. When inoculated in pairs, all probiotic combinations reduced significantly aflatoxin production, and the best reduction was obtained with S. boulardii plus L. delbrueckii (96.1%) followed by S. boulardii plus S. cerevisiae and L. delbrueckii plus S. cerevisiae (71.1 and 66.7%, resp.). All probiotics remained viable in high numbers on the grains even after 300 days. The results of the present study suggest a different use of probiotics as an alternative treatment to prevent aflatoxin production in peanut grains. PMID:26221629

  20. Aflatoxin B1 in poultry: toxicology, metabolism and prevention.

    PubMed

    Rawal, Sumit; Kim, Ji Eun; Coulombe, Roger

    2010-12-01

    Aflatoxins (AF) are ubiquitous in corn-based animal feed and causes hepatotoxic and hepatocarcinogenic effects. The most important AF in terms of toxic potency and occurrence is aflatoxin B1 (AFB1). Poultry, especially turkeys, are extremely sensitive to the toxic and carcinogenic action of AFB1, resulting in millions of dollars in annual losses to producers due to reduced growth rate, increased susceptibility to disease, reduced egg production and other adverse effects. The extreme sensitivity of turkeys and other poultry to AFB1 is associated with efficient hepatic cytochrome P450-mediated bioactivation and deficient detoxification by glutathione S-transferases (GST). Discerning the biochemical and molecular mechanisms of this extreme sensitivity of poultry to AFB1, will contribute in the development of novel strategies to increase aflatoxin resistance. Since AFB1 is an unavoidable contaminant of corn-based poultry feed, chemoprevention strategies aimed at reducing AFB1 toxicity in poultry and in other animals have been the subject of numerous studies. This brief review summarizes many of the key recent findings regarding the action of aflatoxins in poultry. Copyright © 2010 Elsevier Ltd. All rights reserved.

  1. Static Hot Air and Infrared Rays Roasting are Efficient Methods for Aflatoxin Decontamination on Hazelnuts

    PubMed Central

    Siciliano, Ilenia; Dal Bello, Barbara; Zeppa, Giuseppe; Spadaro, Davide; Gullino, Maria Lodovica

    2017-01-01

    Aflatoxins are a group of secondary metabolites produced by members of Aspergillus Section Flavi that are dangerous to humans and animals. Nuts can be potentially contaminated with aflatoxins, often over the legal threshold. Food processes, including roasting, may have different effects on mycotoxins, and high temperatures have proven to be very effective in the reduction of mycotoxins. In this work, two different roasting methods—traditional static hot air roasting and infra-red rays roasting—were applied and compared for the detoxification of hazelnuts from Italy and Turkey. At the temperature of 140 °C for 40 min of exposure, detoxification was effective for both roasting techniques. Residual aflatoxins after infra-red rays treatments were lower compared to static hot air roasting. On Italian hazelnuts, residual aflatoxins were lower than 5%, while for Turkish hazelnuts they were lower than 15% after 40 min of exposure to an infra-red rays roaster. After roasting, the perisperm was detached from the nuts and analyzed for aflatoxin contents. Residual aflatoxins in the perisperm ranged from 80% up to 100%. After roasting, the lipid profile and the nutritional quality of hazelnuts were not affected. Fatty acid methyl esters analyses showed a similar composition for Italian and Turkish hazelnuts. PMID:28230792

  2. Toxicity of aflatoxin B1 towards the vitamin D receptor (VDR).

    PubMed

    Costanzo, Paola; Santini, Antonello; Fattore, Luigi; Novellino, Ettore; Ritieni, Alberto

    2015-02-01

    This research describes an unexpected toxicity of the aflatoxin B1 towards the vitamin D receptors. Rickets is a childhood disease, and calcium deficiency is the aetiological cause in Africa, being primarily associated with nutritional problems; in this research the contribution of aflatoxin B1 exposure during the early months of life is an interesting factor to deepen in order to prevent liver damages or the development of rickets. The results show that the expression of vitamin D receptor in osteosarcoma cell line SAOS-2 is significantly down-modulated by exposure to aflatoxin B1. This seems to suggest that Aflatoxin B1, toxic towards the vitamin D receptor, interferes with the actions of the vitamin D on calcium binding gene expression in the kidney and intestine. Experimental data indicate a 58% and 86% decrease if the cells are exposed to 5 ng/mL and 50 ng/mL of aflatoxin B1, respectively. These results seem to indicate that natural occurrence of the aflatoxin B1 and allelic variant of vitamin D receptor on (F allele) increase the risk of developing rickets of African children.

  3. Impact of aflatoxin B1 on the pharmacokinetic disposition of enrofloxacin in broiler chickens.

    PubMed

    Kalpana, Starling; Srinivasa Rao, G; Malik, Jitendra K

    2015-09-01

    The potential impact of subchronic exposure of aflatoxin B1 was investigated on the pharmacokinetic disposition of enrofloxacin in broiler chickens. Broiler chickens given either normal or aflatoxin B1 (750μg/kg diet) supplemented diet for 6 weeks received a single oral dose of enrofloxacin (10mg/kg body wt). Blood samples were drawn from the brachial vein at predetermined time intervals after drug administration. Enrofloxacin plasma concentrations analyzed by RP-HPLC were significantly lower in aflatoxin B1-exposed broiler chickens at 0.167, 0.5 and 1.0h after drug administration. In aflatoxin B1-exposed broiler chickens, the absorption rate constant (ka) of enrofloxacin (0.20±0.05h(-1)) was significantly decreased as compared to the unexposed birds (0.98±0.31h(-1)). The values of [Formula: see text] , tmax and AUC0-∞ of enrofloxacin were nonsignificantly increased by 17%, 26% and 17% in aflatoxin-exposed broiler chickens, respectively. Subchronic aflatoxin B1 exposure markedly decreased the initial absorption of enrofloxacin without significantly influencing other pharmacokinetic parameters in broiler chickens.

  4. Static Hot Air and Infrared Rays Roasting are Efficient Methods for Aflatoxin Decontamination on Hazelnuts.

    PubMed

    Siciliano, Ilenia; Dal Bello, Barbara; Zeppa, Giuseppe; Spadaro, Davide; Gullino, Maria Lodovica

    2017-02-21

    Aflatoxins are a group of secondary metabolites produced by members of Aspergillus Section Flavi that are dangerous to humans and animals. Nuts can be potentially contaminated with aflatoxins, often over the legal threshold. Food processes, including roasting, may have different effects on mycotoxins, and high temperatures have proven to be very effective in the reduction of mycotoxins. In this work, two different roasting methods-traditional static hot air roasting and infra-red rays roasting-were applied and compared for the detoxification of hazelnuts from Italy and Turkey. At the temperature of 140 °C for 40 min of exposure, detoxification was effective for both roasting techniques. Residual aflatoxins after infra-red rays treatments were lower compared to static hot air roasting. On Italian hazelnuts, residual aflatoxins were lower than 5%, while for Turkish hazelnuts they were lower than 15% after 40 min of exposure to an infra-red rays roaster. After roasting, the perisperm was detached from the nuts and analyzed for aflatoxin contents. Residual aflatoxins in the perisperm ranged from 80% up to 100%. After roasting, the lipid profile and the nutritional quality of hazelnuts were not affected. Fatty acid methyl esters analyses showed a similar composition for Italian and Turkish hazelnuts.

  5. Exposure and preventive measure to reduce high and daily exposure to Bacillus thuringiensis in potted plant production.

    PubMed

    Madsen, Anne Mette; Zervas, Athanasios; Tendal, Kira; Matthiesen, Christoffer B; Koponen, Ismo Kalevi; Hansen, Erik Wind

    2014-07-01

    The bacterium Bacillus thuringiensis (Bt) is the active organism in a variety of commercially available products used worldwide as biopesticides. Bt products are applied in large outdoor areas as well as in indoor environments. Even though it has been sold for decades, not much is known about the occupational exposure to Bt. The aim of this study was to obtain knowledge about the exposure to Bt subspecies israelensis (Bti) in a propagation section in a greenhouse, where Bti is applied hourly by a spray boom, and to test a preventive measure to reduce the exposure to airborne Bti. Furthermore, we wanted to study the exposure during work with potted plants treated earlier with Bti. Exposure to aerosols with Bti was measured repeatedly by personal and stationary samplers before and after the intervention. Bti was identified by polymerase chain reaction in air and soil samples. Personal exposure to inhalable Bti in the propagation section was 3×10(5) cfu m(-3) (median level, n = 22); the personal exposure of people working with plants treated earlier with Bti was 3200 cfu m(-3) (median level, n = 17). The highest single measure was found for the person working with the spray boom (7×10(5) cfu m(-3)) but airborne Bti was present at all sampling stations in the propagation section. Bti constituted a high share of the airborne cultivable bacteria and a smaller share of the soilborne bacteria in the propagation section. In a human cell assay, spiking an aerosol sample with a product with Bti increased the inflammatory potential of an aerosol sample from the greenhouse significantly. Based on the inflammatory potential and the high personal exposure, a cover around the spray boom was built as an attempt to reduce the daily exposure to Bti. The cover reduced the personal exposure to Bti from 3.0×10(5) cfu m(-3) to 1.8×10(4) cfu m(-3). The exposure was thus reduced by a factor 17, which is a considerable reduction. Bti was present in different particle size fractions with

  6. Competing for Consciousness: Prolonged Mask Exposure Reduces Object Substitution Masking

    ERIC Educational Resources Information Center

    Goodhew, Stephanie C.; Visser, Troy A. W.; Lipp, Ottmar V.; Dux, Paul E.

    2011-01-01

    In object substitution masking (OSM) a sparse, temporally trailing 4-dot mask impairs target identification, even though it has different contours from, and does not spatially overlap with the target. Here, we demonstrate a previously unknown characteristic of OSM: Observers show reduced masking at prolonged (e.g., 640 ms) relative to intermediate…

  7. Aflatoxins in Brazilian Peanut Confection.

    PubMed

    2016-04-07

    The study's objectives were to evaluate a method for the determination of aflatoxins (AFs) in the Brazilian peanut confection "Paçoca" and to apply the method in investigating AF concentrations in Paçoca marketed in São Paulo State throughout 2013. Results of another survey conducted between 1994 and 2002 with another method were also reported. The current method consists of immunoaffinity column cleanup, LC with postcolumn derivatization for AF fluorescence enhancement, and fluorescence determination for the toxins. The mean recovery and mean RSDr values were 88.6 and 7.9%, respectively. The LODs for aflatoxin B1, aflatoxin B2, aflatoxin G1, and aflatoxin G2 were 0.04, 0.01, 0.02, and 0.01 ng/g; and the LOQs were 0.15, 0.04, 0.07, and 0.04 ng/g, respectively. Results of the two survey studies indicate that the contamination of AFs in Paçoca remains a public health problem. In the 2013 survey, 71 of 100 samples (71%) had AFs contamination ranging from 0.3 to 41.8 ng/g, with 12 samples (12%) containing >20 ng/g of the toxins, whereas in the 1994-2002 survey, 73 of 150 samples (51%) had AFs contamination ranging from 9 to 1439 ng/g with 65 samples (45%) containing levels >20 ng/g.

  8. Inhibition of aflatoxin formation by some spices.

    PubMed

    Mabrouk, S S; El-Shayeb, N M

    1980-01-01

    The effects of black pepper, cinnamon, peppermint, cumin, ginger and clove on growth and aflatoxin formation of Aspergillus flavus were studied in rice powdercorn steep (RC) medium. The effects of the first five spices were judged to be inhibition of aflatoxin formation rather than of mycelial growth. Clove completely inhibited both mycelial growth and aflatoxin formation at a concentration above 0.1%. No aflatoxin was produced when cumin and mint levels of 5% and 10% were used. Black pepper and ginger levels of 10% decreased aflatoxin formation by 100%. Higher concentrations of cinnamon, mint, cumin and ginger stimulated mycelial growth.

  9. Modulation of macrophage activity by aflatoxins B1 and B2 and their metabolites aflatoxins M1 and M2.

    PubMed

    Bianco, G; Russo, R; Marzocco, S; Velotto, S; Autore, G; Severino, L

    2012-05-01

    Aflatoxins are natural contaminants frequently found both in food and feed. Many of them exert immunomodulatory properties in mammals; therefore, the aim of the current study was to investigate immune-effects of AFB1, AFB2, AFM1 and AFM2, alone and differently combined, in J774A.1 murine macrophages. MTT assay showed that AFB1, alone and combined with AFB2, possess antiproliferative activity only at the highest concentration; such effect was not shown by their hydroxylated metabolites, AFM1 and AFM2, respectively. However, the immunotoxic effects of the aflatoxins evaluated in the current study may be due to the inhibition of production of active oxygen metabolites such as NO. Cytofluorimetric assay in macrophages exposed to aflatoxins (10-100 μM) revealed that their cytoxicity is not related to apoptotic pathways. Nevertheless, a significant increase of the S phase cell population accompanied by a decrease in G0/G1 phase cell population was observed after AFB1 treatment. In conclusion, the results of the current study suggest that aflatoxins could compromise the macrophages functions; in particular, co-exposure to AFB1, AFB2, AFM1 and AFM2 may exert interactions which can significantly affect immunoreactivity.

  10. Effectiveness of pulsed light treatment for degradation and detoxification of aflatoxin B1 and B2 in rough rice and rice bran

    USDA-ARS?s Scientific Manuscript database

    Aflatoxins primarily accumulate in the hull and bran layers of rough rice making these by-products of rice milling unsuitable for animal feed or human consumption. Contaminated rough rice is also a potential source of aflatoxin exposure to workers handling the grain during post-harvest storage and p...

  11. Reduction of aflatoxin B1 in stored peanuts (Arachis hypogaea L.) using Saccharomyces cerevisiae.

    PubMed

    Prado, G; Madeira, J E G Cruz; Morais, V A D; Oliveira, M S; Souza, R A; Peluzio, J M; Godoy, I J; Silva, J F M; Pimenta, R S

    2011-06-01

    Aflatoxin B(1) is a toxigenic and carcinogenic compound produced by Aspergillus flavus and Aspergillus parasiticus. To inhibit aflatoxin contamination of peanuts, seeds of two peanut breeds, IAC Caiapó and IAC Runner 886, were inoculated with A. parasiticus (1.0 × 10(6) spores per ml) and the yeast Saccharomyces cerevisiae (3.2 × 10(7) cells per ml) and incubated at 25°C for 7 and 15 days. Two experiments were conducted for each incubation period separately. The treatments were completely randomized, with three replications per treatment. Treatments included the two cultivars and three types of inoculation (pathogen alone, yeast and pathogen, and yeast 3 h before pathogen). Aflatoxin B(1) was quantified with a densitometer at 366 nm after thin layer chromatography. Aflatoxin B(1) contamination in peanuts was reduced after the addition of S. cerevisiae. The concentration of aflatoxin B(1) decreased by 74.4 and 55.9% after 7 and 15 days, respectively. The greatest aflatoxin reduction was observed when S. cerevisiae was inoculated 3 h before the pathogen in IAC Caiapó seeds and incubated for 7 days at 25°C. The use of S. cerevisiae is a promising strategy for biological control of aflatoxin contamination in peanuts.

  12. Detoxification of Aflatoxin-Contaminated Maize by Neutral Electrolyzed Oxidizing Water

    PubMed Central

    Jardon-Xicotencatl, Samantha; Díaz-Torres, Roberto; Marroquín-Cardona, Alicia; Villarreal-Barajas, Tania; Méndez-Albores, Abraham

    2015-01-01

    Aflatoxins, a group of extremely toxic mycotoxins produced by Aspergillus flavus, A. parasiticus and A. nomius, can occur as natural contaminants of certain agricultural commodities, particularly maize. These toxins have been shown to be hepatotoxic, carcinogenic, mutagenic and cause severe human and animal diseases. The effectiveness of neutral electrolyzed oxidizing water (NEW) on aflatoxin detoxification was investigated in HepG2 cells using several validation methodologies such as the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, the induction of lipid peroxidation, the oxidative damage by means of glutathione modulation, the Ames test and the alkaline Comet assay. Our results showed that, after the aflatoxin-contaminated maize containing 360 ng/g was soaked in NEW (60 mg/L available chlorine, pH 7.01) during 15 min at room temperature, the aflatoxin content did not decrease as confirmed by the immunoaffinity column and ultra performance liquid chromatography methods. Aflatoxin fluorescence strength of detoxified samples was similar to untreated samples. However, aflatoxin-associated cytotoxicity and genotoxicity effects were markedly reduced upon treatment. According to these results, NEW can be effectively used to detoxify aflatoxin-contaminated maize. PMID:26512692

  13. Dynamic variation of bioactive compounds and aflatoxins in contaminated Radix Astragali during extraction process.

    PubMed

    Hu, Yichen; Kong, Weijun; Luo, Hongli; Zhao, Lianhua; Yang, Meihua

    2016-03-30

    Although increasing attention has been paid to the health threat caused by mycotoxins in commodities such as food or medicines, mycotoxin transfer processes from crude material to products have raised little concern so far. Radix Astragali is a commonly used edible and medicinal herbal plant that is susceptible to contamination with aflatoxins from Aspergillus flavus. There have been no studies on mycotoxin transfer into pharmaceutical preparations or derivative products. To facilitate the aflatoxin reduction and bioactivity retention, the dynamic variations of aflatoxins as well as herbal compounds, namely calycosin-7-glucoside, astragaloside and formononetin, in Radix Astragali contaminated by A. flavus during water decoction and ethanol refluxing treatments were evaluated simultaneously by an ultra-fast liquid chromatography-triple quadrupole linear ion trap mass spectrometry method. After the extraction processes, although the amount of alfatoxins was reduced remarkably, aflatoxin residuals in preparation still exceed recommended limits, manifesting the great need to establish a limit for aflatoxins in herbal extractions or derivative products. Meanwhile, due to the hydrolysis of glucoside, water decoction period should be no longer than 4 h. This investigation would benefit from the determination of the dynamic variation of aflatoxins in infected herbs in preparation treatments, in order to further develop aflatoxin limits in herbal preparations. © 2015 Society of Chemical Industry.

  14. Detoxification of Aflatoxin-Contaminated Maize by Neutral Electrolyzed Oxidizing Water.

    PubMed

    Jardon-Xicotencatl, Samantha; Díaz-Torres, Roberto; Marroquín-Cardona, Alicia; Villarreal-Barajas, Tania; Méndez-Albores, Abraham

    2015-10-23

    Aflatoxins, a group of extremely toxic mycotoxins produced by Aspergillus flavus, A. parasiticus and A. nomius, can occur as natural contaminants of certain agricultural commodities, particularly maize. These toxins have been shown to be hepatotoxic, carcinogenic, mutagenic and cause severe human and animal diseases. The effectiveness of neutral electrolyzed oxidizing water (NEW) on aflatoxin detoxification was investigated in HepG2 cells using several validation methodologies such as the 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide assay, the induction of lipid peroxidation, the oxidative damage by means of glutathione modulation, the Ames test and the alkaline Comet assay. Our results showed that, after the aflatoxin-contaminated maize containing 360 ng/g was soaked in NEW (60 mg/L available chlorine, pH 7.01) during 15 min at room temperature, the aflatoxin content did not decrease as confirmed by the immunoaffinity column and ultra performance liquid chromatography methods. Aflatoxin fluorescence strength of detoxified samples was similar to untreated samples. However, aflatoxin-associated cytotoxicity and OPEN ACCESS Toxins 2015, 7 4295 genotoxicity effects were markedly reduced upon treatment. According to these results, NEW can be effectively used to detoxify aflatoxin-contaminated maize.

  15. Reduced susceptibility to amoxicillin of oral streptococci following amoxicillin exposure.

    PubMed

    Chardin, H; Yasukawa, K; Nouacer, N; Plainvert, C; Aucouturier, P; Ergani, A; Descroix, V; Toledo-Arenas, R; Azerad, J; Bouvet, A

    2009-08-01

    As antibiotic pressure often triggers bacterial resistance, the use of short-duration therapies is increasingly recommended. The objective of the present study was to evaluate both the clinical efficiency and the impact on oral streptococci of a 3 day versus a 7 day amoxicillin therapy for odontogenic infection requiring tooth extraction. On day 0, patients were randomly assigned to a 3 day or 7 day amoxicillin treatment. The tooth was extracted on day 2 and the post-operative follow-up was carried out on day 9. Oral flora was collected on days 0, 9 and 30, and the susceptibility of the streptococci to amoxicillin was determined. The results showed that treatment with amoxicillin for 3 or 7 days had a similar clinical efficiency, and also induced similar selection of oral streptococci with reduced susceptibility to amoxicillin, suggesting that the selection of strains with reduced susceptibility to amoxicillin is a rapid phenomenon, appearing even with short-duration therapies.

  16. Have Regulatory Efforts to Reduce Organophosphorus Insecticide Exposures Been Effective?

    PubMed Central

    Clune, Alison L.; Ryan, P. Barry

    2012-01-01

    Background: The Food Quality Protection Act (FQPA) was signed into law in 1996 to strengthen the regulation of pesticide tolerances in food. Organophosphorus (OP) insecticides were the first group of pesticides reviewed by the U.S. Environmental Protection Agency (EPA) under the new law. Objective: Our goal was to determine whether urinary concentrations of dialkylphosphate (DAP) metabolites of OP pesticides declined between the National Health and Nutrition Examination Survey (NHANES) III and NHANES 1999–2004. Methods: Using mass spectrometry–based methods, we analyzed urine samples from a nationally representative sample of 2,874 adults 20–59 years of age in NHANES 1999–2004 and samples from a non-nationally representative sample of 197 adult participants for NHANES III (1988–1994) for six common DAP metabolites of OP pesticides. Results: Median urinary DAP concentrations decreased by more than half between NHANES III and NHANES 2003–2004. Reductions of about 50%–90% were also observed for 95th percentile concentrations of five of the six metabolites. Frequencies of detection (FODs) decreased in all six metabolites (< 50% reduction). On average, median and 95th percentile concentrations and FODs showed a larger decrease in diethylphosphate metabolites than dimethylphosphate metabolites. Conclusions: Human exposure to OP insecticides as assessed by urinary DAP concentrations has decreased since the implementation of the FQPA, although we cannot be certain that U.S. EPA actions in response to the FQPA directly caused the decrease in DAP concentrations. PMID:22251442

  17. Mitigating flood exposure: Reducing disaster risk and trauma signature.

    PubMed

    Shultz, James M; McLean, Andrew; Herberman Mash, Holly B; Rosen, Alexa; Kelly, Fiona; Solo-Gabriele, Helena M; Youngs, Georgia A; Jensen, Jessica; Bernal, Oscar; Neria, Yuval

    2013-01-01

    Introduction. In 2011, following heavy winter snowfall, two cities bordering two rivers in North Dakota, USA faced major flood threats. Flooding was foreseeable and predictable although the extent of risk was uncertain. One community, Fargo, situated in a shallow river basin, successfully mitigated and prevented flooding. For the other community, Minot, located in a deep river valley, prevention was not possible and downtown businesses and one-quarter of the homes were inundated, in the city's worst flood on record. We aimed at contrasting the respective hazards, vulnerabilities, stressors, psychological risk factors, psychosocial consequences, and disaster risk reduction strategies under conditions where flood prevention was, and was not, possible. Methods. We applied the "trauma signature analysis" (TSIG) approach to compare the hazard profiles, identify salient disaster stressors, document the key components of disaster risk reduction response, and examine indicators of community resilience. Results. Two demographically-comparable communities, Fargo and Minot, faced challenging river flood threats and exhibited effective coordination across community sectors. We examined the implementation of disaster risk reduction strategies in situations where coordinated citizen action was able to prevent disaster impact (hazard avoidance) compared to the more common scenario when unpreventable disaster strikes, causing destruction, harm, and distress. Across a range of indicators, it is clear that successful mitigation diminishes both physical and psychological impact, thereby reducing the trauma signature of the event. Conclusion. In contrast to experience of historic flooding in Minot, the city of Fargo succeeded in reducing the trauma signature by way of reducing risk through mitigation.

  18. Community-Based Intervention to Reduce Pesticide Exposure to Farmworkers and Potential Take-Home Exposure to their Families

    PubMed Central

    Bradman, Asa; Salvatore, Alicia L.; Boeniger, Mark; Castorina, Rosemary; Snyder, John; Barr, Dana B.; Jewell, Nicholas P.; Kavanagh-Baird, Geri; Striley, Cynthia; Eskenazi, Brenda

    2015-01-01

    The U.S. EPA Worker Protection Standard requires pesticide safety training for farmworkers. Combined with re-entry intervals, these regulations are designed to reduce pesticide exposure. Little research has been conducted on whether additional steps may reduce farmworker exposure and the potential for take-home exposure to their families. We conducted an intervention with 44 strawberry harvesters (15 control and 29 intervention group members) to determine whether education, encouragement of handwashing, and the use of gloves and removable coveralls reduced exposure. Post-intervention, we collected foliage and urine samples, as well as hand rinse, lower-leg skin patch, and clothing patch samples. Post-intervention loading of malathion on hands was lower among workers who wore gloves compared to those who did not (median = 8.2 vs 777.2 μg/pair, respectively (p<0.001)); similarly, median MDA levels in urine were lower among workers who wore gloves (45.3 vs 131.2 μg/g creatinine, p<0.05). Malathion was detected on clothing (median = 0.13 μg/cm2), but not on skin. Workers who ate strawberries had higher MDA levels in urine (median=114.5 vs 39.4 μg/g creatinine, p<0.01). These findings suggest that wearing gloves reduces pesticide exposure to workers contacting strawberry foliage containing dislodgeable residues. Additionally, wearing gloves and removing work clothes before returning home could reduce transport of pesticides to worker homes. Behavioral interventions are needed to reduce consumption of strawberries in the field. PMID:18368011

  19. Community-based intervention to reduce pesticide exposure to farmworkers and potential take-home exposure to their families.

    PubMed

    Bradman, Asa; Salvatore, Alicia L; Boeniger, Mark; Castorina, Rosemary; Snyder, John; Barr, Dana B; Jewell, Nicholas P; Kavanagh-Baird, Geri; Striley, Cynthia; Eskenazi, Brenda

    2009-01-01

    The US EPA Worker Protection Standard requires pesticide safety training for farmworkers. Combined with re-entry intervals, these regulations are designed to reduce pesticide exposure. Little research has been conducted on whether additional steps may reduce farmworker exposure and the potential for take-home exposure to their families. We conducted an intervention with 44 strawberry harvesters (15 control and 29 intervention group members) to determine whether education, encouragement of handwashing, and the use of gloves and removable coveralls reduced exposure. Post-intervention, we collected foliage and urine samples, as well as hand rinse, lower-leg skin patch, and clothing patch samples. Post-intervention loading of malathion on hands was lower among workers who wore gloves compared to those who did not (median=8.2 vs. 777.2 microg per pair, respectively (P<0.001)); similarly, median MDA levels in urine were lower among workers who wore gloves (45.3 vs. 131.2 microg/g creatinine, P<0.05). Malathion was detected on clothing (median=0.13 microg/cm(2)), but not on skin. Workers who ate strawberries had higher malathion dicarboxylic acid levels in urine (median=114.5 vs. 39.4 microg/g creatinine, P<0.01). These findings suggest that wearing gloves reduces pesticide exposure to workers contacting strawberry foliage containing dislodgeable residues. Additionally, wearing gloves and removing work clothes before returning home could reduce transport of pesticides to worker homes. Behavioral interventions are needed to reduce consumption of strawberries in the field.

  20. Aflatoxin Contamination of Commercial Maize Products during an Outbreak of Acute Aflatoxicosis in Eastern and Central Kenya

    PubMed Central

    Lewis, Lauren; Onsongo, Mary; Njapau, Henry; Schurz-Rogers, Helen; Luber, George; Kieszak, Stephanie; Nyamongo, Jack; Backer, Lorraine; Dahiye, Abdikher Mohamud; Misore, Ambrose; DeCock, Kevin; Rubin, Carol

    2005-01-01

    In April 2004, one of the largest aflatoxicosis outbreaks occurred in rural Kenya, resulting in 317 cases and 125 deaths. Aflatoxin-contaminated homegrown maize was the source of the outbreak, but the extent of regional contamination and status of maize in commercial markets (market maize) were unknown. We conducted a cross-sectional survey to assess the extent of market maize contamination and evaluate the relationship between market maize aflatoxin and the aflatoxicosis outbreak. We surveyed 65 markets and 243 maize vendors and collected 350 maize products in the most affected districts. Fifty-five percent of maize products had aflatoxin levels greater than the Kenyan regulatory limit of 20 ppb, 35% had levels > 100 ppb, and 7% had levels > 1,000 ppb. Makueni, the district with the most aflatoxicosis case-patients, had significantly higher market maize aflatoxin than did Thika, the study district with fewest case-patients (geometric mean aflatoxin = 52.91 ppb vs. 7.52 ppb, p = 0.0004). Maize obtained from local farms in the affected area was significantly more likely to have aflatoxin levels > 20 ppb compared with maize bought from other regions of Kenya or other countries (odds ratio = 2.71; 95% confidence interval, 1.12–6.59). Contaminated homegrown maize bought from local farms in the affected area entered the distribution system, resulting in widespread aflatoxin contamination of market maize. Contaminated market maize, purchased by farmers after their homegrown supplies are exhausted, may represent a source of continued exposure to aflatoxin. Efforts to successfully interrupt exposure to aflatoxin during an outbreak must consider the potential role of the market system in sustaining exposure. PMID:16330360

  1. EPA Awards $500,000 to Help Reduce Childrens Exposure to Pesticides

    EPA Pesticide Factsheets

    (03/17/2016 - ATLANTA)-- U.S. Environmental Protection Agency (EPA) announced two grants to help reduce students', teachers' and staffs' exposure to pests and pesticides in our nation's schools, while saving money, energy and pesticide treatment cost

  2. EPA Awards $500,000 to Help Reduce Childrens Exposure to Pesticides

    EPA Pesticide Factsheets

    WASHINGTON-- U.S. Environmental Protection Agency (EPA) announced two grants to help reduce students', teachers' and staffs' exposure to pests and pesticides in our nation's schools, while saving money, energy and pesticide treatment costs.

  3. Molecular biomarkers for aflatoxins: from adducts to gene mutations to human liver cancer.

    PubMed

    Groopman, J D; Wang, J S; Scholl, P

    1996-02-01

    Over the past 30 years there have been extensive efforts to investigate the association between aflatoxin exposure and human liver cancer. These studies have been hindered by the lack of adequate dosimetry data on aflatoxin intake, excretion, and metabolism in people, as well as by the general poor quality of worldwide cancer morbidity and mortality statistics. These realities have spurred the efforts to develop new technologies to assess exposure status and risk for aflatoxins, and these agents are among the few environmental carcinogens for which quantitative risk assessments have been attempted. One of the goals of these risk assessments has been the development of primary and secondary preventive intervention methods to lower the human health impact from aflatoxin exposures. The long-term goal of the research described herein is the application of biomarkers to the development of preventive interventions for use in human populations at high risk for cancer. Several of the aflatoxin-specific biomarkers have been validated in epidemiologic studies and are now available for use as intermediate biomarkers in prevention trials. The development of these aflatoxin biomarkers has been based upon the knowledge of the biochemistry and toxicology of aflatoxins gleaned from both experimental and human studies. These biomarkers have been utilized subsequently in experimental models to provide data on the modulation of the markers under different situations of disease risk. This systematic approach provides encouragement for preventive interventions and should serve as a template for the development for the development and validation of other chemical-specific biomarkers and their application to cancer or other chronic diseases.

  4. Determination of Aflatoxins in Peanut Products in the Northeast Region of São Paulo, Brazil

    PubMed Central

    Oliveira, Carlos A. F.; Gonçalves, Natália B.; Rosim, Roice E.; Fernandes, Andrezza M.

    2009-01-01

    The aim of the present study was to determine aflatoxin levels in peanut products traded in the Northeast region of São Paulo, Brazil. To this end, 240 samples of peanut products traded in the cities of Araras, Leme, Pirassununga and Porto Ferreira were collected from June 2006 to May 2007. The samples were analyzed for aflatoxins (AF) B1, B2, G1 and G2 by high performance liquid chromatography. Results showed 44.2% samples positive for AF at levels of 0.5 to 103.8 μg·kg−1. Nine of the positive samples (3.7% of the analysed samples) had total aflatoxin concentrations (B1+B2+G1+G2) higher than the limit established by Brazilian regulations (20 μg·kg−1). Based on the above data, the probable mean daily intake (PDIM) of aflatoxins from peanut products in the Northeast region of São Paulo was estimated to be 0.23 ng kg b.w. day−1. Although this PDIM value was relatively low, results indicate that aflatoxin contamination of peanut products may be a public health concern in Brazil, when considering the potential exposure of highly susceptible consumers. For example, it should be emphasized that children are potentially exposed to aflatoxins, since they consume large quantities of peanut candies, and these products had the highest number of samples positive for AFB1. PMID:19333440

  5. Protective interventions to prevent aflatoxin-induced carcinogenesis in developing countries.

    PubMed

    Groopman, John D; Kensler, Thomas W; Wild, Christopher P

    2008-01-01

    The public health impact of aflatoxin exposure is pervasive in economically developing countries; consequently, we need to design intervention strategies for prevention that are practicable for these high-risk populations. The adverse health consequences of aflatoxins in populations are quite varied, eliciting acute effects, such as rapid death, and chronic outcomes, such as hepatocellular carcinoma. Furthermore, a number of epidemiological studies describe a variety of general adverse health effects associated with aflatoxin, such as impaired growth in children. Thus, the magnitude of the problem is disseminated across the entire spectrum of age, gender, and health status in the population. The aflatoxins multiplicatively increase the risk of liver cancer in people chronically infected with hepatitis B virus (HBV), which illustrates the deleterious impact that even low toxin levels in the diet can pose for human health. Thus other aflatoxin interactions, which likely contribute to the disease burden, still remain to be identified. Therefore, many diverse and appropriate strategies for disease prevention are needed to decrease the incidence of aflatoxin carcinogenesis in developing countries.

  6. Correlation of aflatoxin contamination with zinc content of chicken feed

    SciTech Connect

    Jones, F.T.; Hagler, W.M. Jr.; Hamilton, P.B.

    1984-03-01

    Feed samples from chicken houses in five commercial chicken operations were analyzed for Zn, Mn, Fe, Cu, Cd, and aflatoxin content. Mean aflatoxin content of these samples was 14 ppb (14 ng/g) as opposed to 1.2 ppb in samples taken when the feed was made. Aflatoxin content of the feed samples correlated significantly with Zn content but not with Mn, Fe, or Cu, all of which correlated significantly with Zn. Zn content of unamended feed (<20 ppm (20 ..mu..g/g) is normally supplemented with a mineral premix containing Zn, Mn, Fe, and Cu to meet the nutrient requirements of chickens (40 ppm of Zn). The mean zinc concentration of the feed samples (117 ppm) was about threefold greater than the nutrient requirement and ranged from 58 to 162 ppm in individual samples. These field survey results parallel earlier reports of augmented production of aflatoxin in monocultures of aflatoxigenic fungi in corn and other ingredients supplemented with Zn. These results suggest that stricter control of Zn levels during manufacture could reduce aflatoxing contamination of feed consumed by chickens.

  7. Antifungal Activity and Aflatoxin Degradation of Bifidobacterium Bifidum and Lactobacillus Fermentum Against Toxigenic Aspergillus Parasiticus

    PubMed Central

    Ghazvini, Roshanak Daie; Kouhsari, Ebrahim; Zibafar, Ensieh; Hashemi, Seyed Jamal; Amini, Abolfazl; Niknejad, Farhad

    2016-01-01

    Food and feedstuff contamination with aflatoxins (AFTs) is a serious health problem for humans and animals, especially in developing countries. The present study evaluated antifungal activities of two lactic acid bacteria (LAB) against growth and aflatoxin production of toxigenic Aspergillus parasiticus. The mycelial growth inhibition rate of A. parasiticus PTCC 5286 was investigated in the presence of Bifidobacterium bifidum PTCC 1644 and Lactobacillus fermentum PTCC 1744 by the pour plate method. After seven days incubation in yeast extract sucrose broth at 30°C, the mycelial mass was weighed after drying. The inhibitory activity of LAB metabolites against aflatoxin production by A. parasiticus was evaluated using HPLC method. B. bifidum and L. fermentum significantly reduced aflatoxin production and growth rate of A. parasiticus in comparison with the controls (p≤0.05). LAB reduced total aflatoxins and B1, B2, G1 and G2 fractions by more than 99%. Moreover, LAB metabolites reduced the level of standard AFB1, B2, G1 and G2 from 88.8% to 99.8% (p≤0.05). Based on these findings, B. bifidum and L. fermentum are recommended as suitable biocontrol agents against the growth and aflatoxin production by aflatoxigenic Aspergillus species. PMID:28077976

  8. Absence of the aflatoxin biosynthesis gene, norA, allows accumulation of deoxyaflatoxin B1 in Aspergillus flavus cultures

    PubMed Central

    Ehrlich, Kenneth C.; Chang, Perng-Kuang; Scharfenstein, Lester L.; Cary, Jeffrey W.; Crawford, Jason M.; Townsend, Craig A.

    2010-01-01

    Biosynthesis of the highly toxic and carcinogenic aflatoxins in select Aspergillus species from the common intermediate O-methylsterigmatocystin (OMST) has been postulated to require only the cytochrome P450 monooxygenase, OrdA (AflQ). We now provide evidence that the aryl alcohol dehydrogenase NorA (AflE) encoded by the aflatoxin biosynthetic gene cluster in A. flavus affects the accumulation of aflatoxins in the final steps of aflatoxin biosynthesis. Mutants with inactive norA produced reduced quantities of aflatoxin B1 (AFB1), but elevated quantities of a new metabolite, deoxyAFB1. To explain this result, we suggest that, in the absence of NorA, the AFB1 reduction product, aflatoxicol, is produced and is readily dehydrated to deoxyAFB1 in the acidic medium, enabling us to observe this otherwise minor toxin produced in wild-type A. flavus. PMID:20158523

  9. Heritability of, and genetoypic correlations between, aflatoxin traits and physiological traits for drought tolerance under end of season drought of peanut (Arachis hypogaea L.)

    USDA-ARS?s Scientific Manuscript database

    More rapid progress in breeding peanut for reduced aflatoxin contamination should be achieved with a better understanding of the inheritance of aflatoxin traits and physiological traits that are associated with reduced contamination. The objectives of this study were to estimate the heritability of...

  10. Video filming and pollution measurement as a teaching aid in reducing exposure to airborne pollutants.

    PubMed

    Rosén, G; Andersson, I M

    1989-01-01

    A method called PIMEX has been developed for investigation of the causes of exposure to airborne pollutants at workplaces. The method involves measurement of the subject's exposure with a personal, direct-reading instrument. The sampling signal is transmitted by telemetry to a special video mixer. A video camera is also connected to the video mixer. The camera is used for filming the subject. The video mixer's output signal is fed to a monitor which continuously shows how the subject works and how exposure varies. The method has been used for producing two films on the causes of exposure to solvent and effective measures for reducing exposure: one deals with screen printing and the other with surface treatment at wood-processing plants. The films have been shown at a large number of workplaces at discussions about workplace conditions, proving useful tools in efforts to reduce workplace risks and giving rise to concrete measures and increased interest in the workplace environment.

  11. Aflatoxin binders II: reduction of aflatoxin M1 in milk by sequestering agents of cows consuming aflatoxin in feed.

    PubMed

    Diaz, Duarte E; Hagler, Winston M; Blackwelder, John T; Eve, Julie A; Hopkins, Brinton A; Anderson, Kevin L; Jones, Frank T; Whitlow, Lon W

    2004-02-01

    Sequestering agents bind dietary aflatoxin B1 (AFB1) and reduce absorption from an animal's gastrointestinal tract. As a result, they protect an animal from the toxic effects of AFB1 and reduce transfer of the metabolite, aflatoxin M1 (AFM1), into milk. Three experiments, using late-lactation Holstein cows fed AFB1-contaminated feed, were conducted to evaluate several potential sequestering agents for their abilities to prevent or reduce the transmission of AFM1 into milk. Six agents previously tested in our laboratory for AFB1 binding in vitro were evaluated in these experiments. These were: SA-20, an activated carbon (AC-A); Astra-Ben-20, a sodium bentonite (AB-20); MTB-100, an esterified glucomannan (MTB-100); Red Crown, a calcium bentonite (RC); Flow Guard, a sodium bentonite (FG); and Mycrosorb, a sodium bentonite (MS). Five of the six sequestering agents significantly (P < 0.01) reduced AFM1 contamination of milk (AB-20, 61%; FG, 65%; MS, 50%; MTB-100, 59%; and RC, 31%); whereas, AC-A, activated carbon, had no effect on AFM1 transmission at 0.25% of feed. By the first milking (1 day after cows consumed contaminated feed), AFM1 appeared in milk, then reached maximum levels after three days, and was absent from milk within four days after AFB1 was removed from the feed. Sodium bentonites at 1.2% of feed showed good potential as AFB1 binders; MTB-100, a yeast cell wall product, was equally effective at 0.05% in feed. Potential AFB1 binding agents should be evaluated experimentally to demonstrate efficacy. Our data show that sequestering agents can reduce AFM1 in milk of cows fed AFB1-contaminated feed.

  12. Comparison of the efficiency between two sampling plans for aflatoxins analysis in maize

    PubMed Central

    Mallmann, Adriano Olnei; Marchioro, Alexandro; Oliveira, Maurício Schneider; Rauber, Ricardo Hummes; Dilkin, Paulo; Mallmann, Carlos Augusto

    2014-01-01

    Variance and performance of two sampling plans for aflatoxins quantification in maize were evaluated. Eight lots of maize were sampled using two plans: manual, using sampling spear for kernels; and automatic, using a continuous flow to collect milled maize. Total variance and sampling, preparation, and analysis variance were determined and compared between plans through multifactor analysis of variance. Four theoretical distribution models were used to compare aflatoxins quantification distributions in eight maize lots. The acceptance and rejection probabilities for a lot under certain aflatoxin concentration were determined using variance and the information on the selected distribution model to build the operational characteristic curves (OC). Sampling and total variance were lower at the automatic plan. The OC curve from the automatic plan reduced both consumer and producer risks in comparison to the manual plan. The automatic plan is more efficient than the manual one because it expresses more accurately the real aflatoxin contamination in maize. PMID:24948911

  13. Effect of sensory exposure on liking for fat- or sugar-reduced biscuits.

    PubMed

    Biguzzi, Coralie; Lange, Christine; Schlich, Pascal

    2015-12-01

    This study investigates the effect of exposure to fat- or sugar-reduced biscuits on liking for these products. Two sets of biscuits were manufactured, each including a standard variant and 4 variants differing by the level of reduction of either fat or sugar content, to 33% of fat content or 28% of sugar content. Biscuit consumers were recruited to eat either the fat (n = 113) or the sugar-reduced set of biscuits (n = 106). They participated in 5 testing sessions, once a week, in laboratory conditions. During each session, they rated their liking of the 5 variants. At the end of each of the 4 first sessions, consumers were given 16 biscuits for their home consumption during the week. Participants were split into 3 groups of exposure: every week, a control group received the standard variant, a "direct" group received the most reduced variant and a "stepwise" group received a more and more reduced variant. After both control and stepwise exposure, almost no evolution of liking was observed. At the end of the direct exposure period to the 33% fat-reduced variant, liking for this variant significantly improved. On the contrary, after the direct exposure to the 28% sugar-reduced variant, liking only improved for 9 and 16% sugar-reduced variants. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Aflatoxins and fumonisins contamination of home-made food (weanimix) from cereal-legume blends for children.

    PubMed

    Kumi, J; Mitchell, N J; Asare, G A; Dotse, E; Kwaa, F; Phillips, T D; Ankrah, N-A

    2014-09-01

    Weanimix is an important food for children in Ghana. Mothers are trained to prepare homemade weanimix from beans, groundnuts and maize for their infants. Groundnuts and maize are prone to aflatoxin contamination while fumonisin contaminates maize. Aflatoxin, is produced by the Asperguillus fungi while fumonisin, is produced by Fusarium fungi. These mycotoxins occur in tropical areas worldwide due to favorable climate for their growth. The objective of the study was to determine the levels of aflatoxin and fumonisin in homemade weanimix in the Ejura-Sekyedumase district in the Ashanti Region of Ghana. Thirty six homemade weanimix samples (50g each) were collected from households. Aflatoxin and fumonisin were measured using a fluorometric procedure described by the Association of Official Analytical Chemist (AOAC official method 993.31, V1 series 4). Aflatoxin and fumonisin were detected in all 36 samples, range 7.9-500ppb. Fumonisin levels range: 0.74-11.0ppm). Thirty (83.3%) of the thirty six samples were over the action limit of 20ppb for aflatoxin with an overall mean of 145.2 ppb whiles 58.3% of the samples had fumonisins above the action limit of 4 ppm with an overall mean of 4.7 ppm. There were significant aflatoxin and fumonisin contamination of homemade weanimix. Children fed on this nutritional food were being exposed to unacceptable levels of aflatoxin and fumonisin. Therefore there is a critical need to educate mothers on the dangers of mycotoxin exposure and to develop strategies to eliminate exposure of children fed homemade weanimix to aflatoxin and fumonisin.

  15. Key roles of vitamins A, C, and E in aflatoxin B1-induced oxidative stress.

    PubMed

    Alpsoy, Lokman; Yalvac, Mehmet Emir

    2011-01-01

    Aflatoxins (Aspergillus flavus toxins) are one of the natural toxic molecules which are produced by a group of fungi called Aspergillus. Foods and drinks contaminated with aflatoxins cause global health and environmental problems. Today in many developing countries, these toxins are leading cause of some liver cancers and serious gastrointestinal problems. Aflatoxins, which are well known to be mutagenic, carcinogenic, hepatotoxic, and immunosuppressive, exert inhibitory effects on biological processes including DNA synthesis, DNA-dependent RNA synthesis, DNA repair, and protein synthesis. Aflatoxins B(1) (AFB(1)) is the most widespread oxidative agent of the aflatoxins. Numerous diverse compounds and extracts have been reported to reduce the aflatoxins induced oxidative stress in the body. Most of these inhibitors including phenylpropanoids, terpenoids, alkaloids, and vitamins are originally derived from plants. Among these, being essential biomolecules, vitamins are used as coenzymes in very significant biological reactions. They also function as nonenzymatic antioxidative agents protecting the cells from oxidative stress-induced toxicity and transformation. This chapter reviews the mechanism of AFB(1)-induced oxidative stress and focuses on the protective effects of vitamins A, C, and E on reducing this stress.

  16. Reduction of aflatoxin production by Aspergillus flavus and Aspergillus parasiticus in interaction with Streptomyces.

    PubMed

    Verheecke, C; Liboz, T; Anson, P; Diaz, R; Mathieu, F

    2015-05-01

    The aim of this study is to investigate aflatoxin gene expression during Streptomyces-Aspergillus interaction. Aflatoxins are carcinogenic compounds produced mainly by Aspergillus flavus and Aspergillus parasiticus. A previous study has shown that Streptomyces-A. flavus interaction can reduce aflatoxin content in vitro. Here, we first validated this same effect in the interaction with A. parasiticus. Moreover, we showed that growth reduction and aflatoxin content were correlated in A. parasiticus but not in A. flavus. Secondly, we investigated the mechanisms of action by reverse-transcriptase quantitative PCR. As microbial interaction can lead to variations in expression of household genes, the most stable [act1, βtub (and cox5 for A. parasiticus)] were chosen using geNorm software. To shed light on the mechanisms involved, we studied during the interaction the expression of five genes (aflD, aflM, aflP, aflR and aflS). Overall, the results of aflatoxin gene expression showed that Streptomyces repressed gene expression to a greater level in A. parasiticus than in A. flavus. Expression of aflR and aflS was generally repressed in both Aspergillus species. Expression of aflM was repressed and was correlated with aflatoxin B1 content. The results suggest that aflM expression could be a potential aflatoxin indicator in Streptomyces species interactions. Therefore, we demonstrate that Streptomyces can reduce aflatoxin production by both Aspergillus species and that this effect can be correlated with the repression of aflM expression.

  17. Aflatoxigenic Fungi and Aflatoxins in Portuguese Almonds

    PubMed Central

    Rodrigues, P.; Venâncio, A.; Lima, N.

    2012-01-01

    Aflatoxin contamination of nuts is an increasing concern to the consumer's health. Portugal is a big producer of almonds, but there is no scientific knowledge on the safety of those nuts, in terms of mycotoxins. The aim of this paper was to study the incidence of aflatoxigenic fungi and aflatoxin contamination of 21 samples of Portuguese almonds, and its evolution throughout the various stages of production. All fungi belonging to Aspergillus section Flavi were identified and tested for their aflatoxigenic ability. Almond samples were tested for aflatoxin contamination by HPLC-fluorescence. In total, 352 fungi belonging to Aspergillus section Flavi were isolated from Portuguese almonds: 127 were identified as A. flavus (of which 28% produced aflatoxins B), 196 as typical or atypical A. parasiticus (all producing aflatoxins B and G), and 29 as A. tamarii (all nonaflatoxigenic). Aflatoxins were detected in only one sample at 4.97 μg/kg. PMID:22666128

  18. Aflatoxin production in meats. I. Stored meats.

    PubMed

    Bullerman, L B; Hartman, P A; Ayres, J C

    1969-11-01

    Aflatoxins were produced on fresh beef (in which bacterial spoilage was delayed with antibiotics), ham, and bacon inoculated with toxinogenic fungi and stored at 15, 20 and 30 C. Meats stored at 10 C were spoiled by bacteria and yeast before detectable levels of aflatoxins were produced. High levels of aflatoxins were formed in meats stored at 20 C; one sample supported the production of 630 mug of aflatoxins per g of meat, the major portion (580 mug) of which was aflatoxin G(1). Meats stored below 30 C developed higher levels of aflatoxin G(1) than B(1), but at 30 C Aspergillus flavus produced equal amounts of B(1) and G(1), whereas A. parasiticus continued to produce more G(1) than B(1).

  19. The Efficacy of Bamboo Charcoal in Comparison with Smectite to Reduce the Detrimental Effect of Aflatoxin B1 on In Vitro Rumen Fermentation of a Hay-Rich Feed Mixture

    PubMed Central

    Jiang, Ya-Hui; Wang, Ping; Yang, Hong-Jian; Chen, Ying

    2014-01-01

    Two commercial materials, a bamboo charcoal (BC) and a smectite clay (SC), were assessed in vitro with aflatoxin B1 (AFB1) in an equilibrium adsorption test. The adsorption capacity and proportion adsorbed (0.381 μg/mg, 0.955) for BC were greater than for SC (0.372 μg/mg, 0.931). The effects of in vitro ruminal fermentation of hay-rich feed incubated with 1.0 μg/mL AFB1 for 0–10 g/L doses of BC and SC were measured at 39 °C for 72 h. The BC and SC binders increased AFB1 loss at dosages ≥1.0 g/L (p < 0.0001). Average AFB1 loss (p < 0.0001) was greater for SC (0.904) than BC (0.881). Both SC and SC addition increased in vitro dry matter loss, and the average dry matter losses were similar. Asymptotic gas volume and volatile fatty acid production were greater for BC than for SC (p < 0.0001). Thus, BC may be as effective as SC in removing aflatoxin B1’s detrimental effects on rumen degradability and fermentation under the occurrence of microbial aflatoxin degradation. PMID:25014194

  20. Synthetic materials to reduce exposure to mycotoxins in fermented foods and beverages

    USDA-ARS?s Scientific Manuscript database

    Mycotoxins are a broad class of toxic fungal metabolites that occasionally contaminate agricultural commodities. Mycotoxin contamination reduces the value of affected commodities and negatively impacts the health of consumers. A popular approach to reduce the effects of exposure to mycotoxins is the...

  1. Does drywall installers' innovative idea reduce the ergonomic exposures of ceiling installation: A field case study.

    PubMed

    Dasgupta, Priyadarshini Sengupta; Punnett, Laura; Moir, Susan; Kuhn, Sarah; Buchholz, Bryan

    2016-07-01

    The study was conducted to assess an intervention suggested by the workers to reduce the physical or ergonomic exposures of the drywall installation task. The drywall installers were asked to brainstorm on innovative ideas that could reduce their ergonomic exposures during the drywall installation work. The workers proposed the idea of using a 'deadman' (narrow panel piece) to hold the panels to the ceiling while installing them. The researcher collected quantitative exposure data (PATH, 3DSSPP) at the baseline and intervention phases and compared the phases to find out any change in the exposure while using the 'deadman'. Results showed that ergonomic exposures (such as overhead arm and awkward trunk postures and heavy load handling) were reduced at the intervention phase while using the 'deadman' with an electrically operated lift. The concept of the 'deadman', which was shown to help reduce musculoskeletal exposures during ceiling installation, can be used to fabricate a permanent ergonomic tool to support the ceiling drywall panel. Copyright © 2016 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  2. Manual sorting to eliminate aflatoxin from peanuts.

    PubMed

    Galvez, F C F; Francisco, M L D L; Villarino, B J; Lustre, A O; Resurreccion, A V A

    2003-10-01

    A manual sorting procedure was developed to eliminate aflatoxin contamination from peanuts. The efficiency of the sorting process in eliminating aflatoxin-contaminated kernels from lots of raw peanuts was verified. The blanching of 20 kg of peanuts at 140 degrees C for 25 min in preheated roasters facilitated the manual sorting of aflatoxin-contaminated kernels after deskinning. The manual sorting of raw materials with initially high aflatoxin contents (300 ppb) resulted in aflatoxin-free peanuts (i.e., peanuts in which no aflatoxin was detected). Verification procedures showed that the sorted sound peanuts contained no aflatoxin or contained low levels (<15 ppb) of aflatoxin. The results obtained confirmed that the sorting process was effective in separating contaminated peanuts whether or nor contamination was extensive. At the commercial level, when roasters were not preheated, the dry blanching of 50 kg of peanuts for 45 to 55 min facilitated the proper deskinning and subsequent manual sorting of aflatoxin-contaminated peanut kernels from sound kernels.

  3. Aflatoxins in black tea in Iran.

    PubMed

    Pouretedal, Zohreh; Mazaheri, Mansooreh

    2013-01-01

    Aflatoxins (AFs) are highly toxic, and carcinogenic secondary fungal metabolites and have been detected in various food commodities. In this regard, 40 black tea samples including domestic and imported black tea were analysed for aflatoxin contamination by high-performance liquid chromatography using a post-column derivatisation procedure (Kobra cell) with fluorescence detection. Samples were randomly collected in 2010 from Tehran markets. The results revealed that 30 among 40 samples were contaminated with aflatoxins (27.5% of the total). Mean AFB1 content was 10.0 ng/g and mean of aflatoxin total was 12.07 ng/g for the 11 contaminated samples.

  4. Degradation of aflatoxins in peanut kernels/flour by gaseous ozonation and mild heat treatment.

    PubMed

    Proctor, A D; Ahmedna, M; Kumar, J V; Goktepe, I

    2004-08-01

    Aflatoxins occur naturally in many agricultural crops causing health hazards and economic losses. Despite improved handling, processing and storage, they remain a problem in the peanut industry. Therefore, new ways to detoxify contaminated products are needed to limit economic/health impacts and add value to the peanut industry. The study was conducted (1) to evaluate the effectiveness of ozonation and mild heat in breaking down aflatoxins in peanut kernels and flour, and (2) to quantify aflatoxin destruction compared with untreated samples. Peanut samples were inoculated with known concentrations of aflatoxins B1, B2, G1 and G2. Samples were subjected to gaseous ozonation and under various temperatures (25, 50, 75 degrees C) and exposure times (5, 10, 15 min). Ozonated and non-ozonated samples were extracted in acetonitrile/water, derivatized in a Kobra cell and quantified by high-performance liquid chromatography. Ozonation efficiency increased with higher temperatures and longer treatment times. Regardless of treatment combinations, aflatoxins B1 and G1 exhibited the highest degradation levels. Higher levels of toxin degradation were achieved in peanut kernels than in flour. The temperature effect lessened as the exposure time increased, suggesting that ozonation at room temperature for 10-15 min could yield degradation levels similar to those achieved at higher temperatures while being more economical.

  5. Natural occurrence of aflatoxins in peanuts and peanut butter from Bulawayo, Zimbabwe.

    PubMed

    Mupunga, I; Lebelo, S L; Mngqawa, P; Rheeder, J P; Katerere, D R

    2014-10-01

    Mycotoxins are toxic secondary metabolites produced by filamentous fungi that may contaminate food and pose a health risk, especially in developing countries, where there is a lack of food security and quality is subsumed by food insufficiency. Aflatoxins are the most toxic known mycotoxins and are a significant risk factor for liver and kidney cancer, teratogenicity, undernutrition, and micronutrient malabsorption in both humans and animals. The main aim of the study was to determine the extent of fungal and aflatoxin contamination in peanuts and peanut butter being sold in both the formal and informal markets in Bulawayo, Zimbabwe. Eighteen peanut samples and 11 peanut butter samples were purchased from retail shops and the informal market. Fungal contamination was determined using standard mycology culture methods, while aflatoxin contamination was determined using high-performance liquid chromatography-fluorescence detection. Four of the six peanut samples tested for fungal contamination were infected with Aspergillus flavus/parasiticus, ranging from 3 to 20% of the kernels examined, while 27% (3 of 11) of the peanut butter samples were infected with A. flavus/parasiticus. Ninety-one percent (10 of 11) of the peanut butter samples were contaminated with aflatoxins (mean, 75.66 ng/g, and range, 6.1 to 247 ng/g), and aflatoxin B1 was the most prevalent (mean, 51.0 ng/g, and range, 3.7 to 191 ng/g). Three of the 18 peanut samples were contaminated with aflatoxins (range, 6.6 to 622 ng/g). The commercial peanut butter samples had very high aflatoxin levels, and manufacturers should be sensitized to the detrimental effects of aflatoxins and measures to reduce contamination.

  6. Comprehensive assessment of maize aflatoxin levels in Eastern Kenya, 2005-2007.

    PubMed

    Daniel, Johnni H; Lewis, Lauren W; Redwood, Yanique A; Kieszak, Stephanie; Breiman, Robert F; Flanders, W Dana; Bell, Carlos; Mwihia, John; Ogana, George; Likimani, Sopiato; Straetemans, Masja; McGeehin, Michael A

    2011-12-01

    Aflatoxin, a potent fungal toxin, contaminates 25% of crops worldwide. Since 2004, 477 aflatoxin poisonings associated with eating contaminated maize have been documented in Eastern Kenya, with a case-fatality rate of 40%. We characterized maize aflatoxin contamination during the high-risk season (April-June) after the major harvests in 2005, 2006 (aflatoxicosis outbreak years), and 2007 (a non-outbreak year). Households were randomly selected each year from the region in Kenya where outbreaks have consistently occurred. At each household, we obtained at least one maize sample (n = 716) for aflatoxin analysis using immunoaffinity methods and administered a questionnaire to determine the source (i.e., homegrown, purchased, or relief) and amount of maize in the household. During the years of outbreaks in 2005 and 2006, 41% and 51% of maize samples, respectively, had aflatoxin levels above the Kenyan regulatory limit of 20 ppb in grains that were for human consumption. In 2007 (non-outbreak year), 16% of samples were above the 20-ppb limit. In addition, geometric mean (GM) aflatoxin levels were significantly higher in 2005 (GM = 12.92, maximum = 48,000 ppb) and 2006 (GM = 26.03, maximum = 24,400 ppb) compared with 2007 (GM = 1.95, maximum = 2,500 ppb) (p-value < 0.001). In all 3 years combined, maize aflatoxin levels were significantly higher in homegrown maize (GM = 17.96) when compared with purchased maize (GM = 3.64) or relief maize (GM = 0.73) (p-value < 0.0001). Aflatoxin contamination is extreme within this region, and homegrown maize is the primary source of contamination. Prevention measures should focus on reducing homegrown maize contamination at the household level to avert future outbreaks.

  7. In utero exposure to tobacco smoke and subsequent reduced fertility in females.

    PubMed

    Ye, Xibiao; Skjaerven, Rolv; Basso, Olga; Baird, Donna D; Eggesbo, Merete; Cupul Uicab, Lea Aurora; Haug, Kjell; Longnecker, Matthew P

    2010-11-01

    Animal studies have shown that in utero exposure to chemicals in tobacco smoke reduces female fertility, but epidemiological findings have been inconsistent. We examined the association between in utero exposure to tobacco smoke and female fertility among women in the Norwegian Mother and Child Cohort Study, enrolled from 1999 to 2007. Around the 17th week of pregnancy, participants reported how long they took to conceive (time to pregnancy), and whether their mother smoked while pregnant with the participant. This analysis included 48 319 planned pregnancies among women aged 15-44 years. We estimated fecundability odds ratios (FORs) using a discrete-time survival analysis, adjusting for age, education and adult tobacco smoking. The adjusted FOR for in utero exposure to tobacco smoke among all subjects was 0.96 [95% confidence interval (CI): 0.93, 0.98], among subjects reporting no adult tobacco smoking or passive exposure it was 0.96 (95% CI: 0.93, 0.99) and among subjects reporting adult tobacco smoking or passive exposure it was 0.95 (95% CI: 0.91, 0.99). We performed a probabilistic sensitivity analysis to estimate the effect of exposure and outcome misclassification on the results, and, as expected, the association became more pronounced after taking misclassification into account. This large cohort study supports a small-to-modest association between in utero exposure to tobacco smoke and reduced fertility.

  8. Phenanthrene exposure induces cardiac hypertrophy via reducing miR-133a expression by DNA methylation

    PubMed Central

    Huang, Lixing; Xi, Zhihui; Wang, Chonggang; Zhang, Youyu; Yang, Zhibing; Zhang, Shiqi; Chen, Yixin; Zuo, Zhenghong

    2016-01-01

    Growing evidence indicates that there is an emerging link between environmental pollution and cardiac hypertrophy, while the mechanism is unclear. The objective of this study was to examine whether phenanthrene (Phe) could cause cardiac hypertrophy, and elucidate the molecular mechanisms involved. We found that: 1) Phe exposure increased the heart weight and cardiomyocyte size of rats; 2) Phe exposure led to enlarged cell size, and increased protein synthesis in H9C2 cells; 3) Phe exposure induced important markers of cardiac hypertrophy, such as atrial natriuretic peptide, B-type natriuretic peptide, and c-Myc in H9C2 cells and rat hearts; 4) Phe exposure perturbed miR-133a, CdC42 and RhoA, which were key regulators of cardiac hypertrophy, in H9C2 cells and rat hearts; 5) Phe exposure induced DNA methyltransferases (DNMTs) in H9C2 cells and rat hearts; 6) Phe exposure led to methylation of CpG sites within the miR-133a locus and reduced miR-133a expression in H9C2 cells; 7) DNMT inhibition and miR-133a overexpression could both alleviate the enlargement of cell size and perturbation of CdC42 and RhoA caused by Phe exposure. These results indicated that Phe could induce cardiomyocyte hypertrophy in the rat and H9C2 cells. The mechanism might involve reducing miR-133a expression by DNA methylation. PMID:26830171

  9. Effect of sodium bentonite on the performance and blood variables of broiler chickens intoxicated with aflatoxins.

    PubMed

    Santurio, J M; Mallmann, C A; Rosa, A P; Appel, G; Heer, A; Dageförde, S; Böttcher, M

    1999-03-01

    1. This study was conducted to evaluate the protective effect of natural sodium bentonite (NaB) in the prevention of toxic effects of aflatoxins. Five hundred and twenty-eight 1-d-old Ross male broiler chickens were housed in pens (22 chickens per pen) for 42 d. There were 3 inclusion rates of NaB (0, 2.5, and 5 g/kg) and 2 of aflatoxins (0 and 3 mg/kg food). Each treatment had 4 replicates of 22 chickens. 2. All chickens treated with aflatoxin and without bentonite were adversely affected. NaB treatment at 5.0 g/kg improved body weights at 42 d of age by 31.3%, increased food intake by 23.8% and improved productive efficiency by 40.1%. Weights of liver, heart, pancreas and crop and biochemical variables were not affected by dietary NaB. However, serum phosphorous concentration was reduced by 30% compared with chickens that received aflatoxin. 3. NaB caused no adverse effects on chickens that did not receive aflatoxin. 4. It is concluded that NaB at pH 7.9 partially neutralises the effects of aflatoxins on broiler chickens when included at 5.0 g/kg in the diet.

  10. Lifelong exposure to dietary isoflavones reduces risk of obesity in ovariectomized Wistar rats.

    PubMed

    Kurrat, Anne; Blei, Tina; Kluxen, Felix M; Mueller, Dennis R; Piechotta, Marion; Soukup, Sebastian T; Kulling, Sabine E; Diel, Patrick

    2015-12-01

    Traditional Asian diet rich in soy isoflavones (ISOs) is discussed to be linked to a lower obesity prevalence. In lifelong and short-term exposure scenarios we investigated effects of an ISO-rich diet on the body composition and development of obesity in female rats. Female Wistar rats grew up on ISO-free or ISO-rich control diet (CON ISO: 467 mg/kg diet). Starting postnatal day 83, ovariectomized and intact animals received high calorie Western diet (WD) in the absence or presence of ISO (WD ISO: 431 mg/kg diet) for 12 weeks to induce obesity or maintained on respective control diet (CON). One group starting ISO exposure after ovariectomy mimics short-term ISO exposure in postmenopausal Western women. Lifelong but not short-term ISO exposure resulted in reduced body weight, visceral fat mass, serum leptin, and smaller adipocytes. ISO decreased hepatic SREBP-1c, ACC, FAS, and PPARγ mRNA expression in nonobese animals. Moreover, ovariectomy reduced skeletal muscle weight, which was antagonized by both short-term and lifelong ISO exposure. Our results indicate that in female rats lifelong but not short-term ISO intake reduces the risk to develop obesity. Furthermore, lifelong and short-term ISO exposure may antagonize loss of skeletal muscle mass induced by ovariectomy. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Reducing tobacco smoking and smoke exposure to prevent preterm birth and its complications.

    PubMed

    Wagijo, Mary-Ann; Sheikh, Aziz; Duijts, Liesbeth; Been, Jasper V

    2017-03-01

    Tobacco smoking and smoke exposure during pregnancy are associated with a range of adverse health outcomes, including preterm birth. Also, children born preterm have a higher risk of complications including bronchopulmonary dysplasia and asthma when their mothers smoked during pregnancy. Smoking cessation in early pregnancy can help reduce the adverse impact on offspring health. Counselling interventions are effective in promoting smoking cessation and reducing the incidence of preterm birth. Peer support and incentive-based approaches are likely to be of additional benefit, whereas the effectiveness of pharmacological interventions, including nicotine replacement therapy, has not definitely been established. Smoke-free legislation can help reduce smoke exposure as well as maternal smoking rates at a population level, and is associated with a reduction in preterm birth. Helping future mothers to stop smoking and protect their children from second hand smoke exposure must be a key priority for health care workers and policy makers alike. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Reduced egg viability in codling moth Cydia pomonella (L.) (Lepidoptera: Tortricidae) following adult exposure to novaluron.

    PubMed

    Gökçe, Ayhan; Kim, Soo-Hoon S; Wise, John C; Whalon, Mark E

    2009-03-01

    The codling moth, Cydia pomonella (L.), is one of the principal pests of pome fruits in the world. The effects of novaluron, a benzoylurea chitin synthesis inhibitor insecticide registered for use on apples in the USA, on fecundity and egg viability in codling moth were studied under laboratory conditions. Three different exposure methods were investigated: ingestion, contact and topical spray. Additionally, the duration of novaluron sublethal effects was measured subsequent to the three modes of exposure. The fecundity of codling moth adults was not significantly affected by novaluron with any of the exposure methods. However, novaluron did cause significant reductions in the proportion of egg hatch with all three exposure methods. The duration of sublethal effects was 9 days or more for all modes of exposure, but with the topical spray these effects began to diminish after 6 days. Novaluron does not affect fecundity in codling moth, but has significant sublethal activity by reducing egg viability subsequent to adult exposure. The topical, contact and ingestion exposures all induce sublethal effects after exposure, and these persist to various degrees throughout codling moth oviposition. A more complete understanding of novaluron's lethal and sublethal activities will help IPM practitioners optimize its use for management of the codling moth. 2008 Society of Chemical Industry.

  13. Ameliorating Effects of Bacillus subtilis ANSB060 on Growth Performance, Antioxidant Functions, and Aflatoxin Residues in Ducks Fed Diets Contaminated with Aflatoxins.

    PubMed

    Zhang, Liyuan; Ma, Qiugang; Ma, Shanshan; Zhang, Jianyun; Jia, Ru; Ji, Cheng; Zhao, Lihong

    2016-12-22

    Bacillus subtilis ANSB060 isolated from fish gut is very effective in detoxifying aflatoxins in feed and feed ingredients. The purpose of this research was to investigate the effects of B. subtilis ANSB060 on growth performance, body antioxidant functions, and aflatoxin residues in ducks fed moldy maize naturally contaminated with aflatoxins. A total of 1500 18-d-old male Cherry Valley ducks with similar body weight were randomly assigned to five treatments with six replicates of 50 ducks per repeat. The experiment design consisted of five dietary treatments labeled as C0 (basal diet containing 60% normal maize), M0 (basal diet containing 60% moldy maize contaminated with aflatoxins substituted for normal maize), M500, M1000, and M2000 (M0 +500, 1000 or 2000 g/t aflatoxin biodegradation preparation mainly consisted of B. subtilis ANSB060). The results showed that ducks fed 22.44 ± 2.46 μg/kg of AFB₁ (M0) exhibited a decreasing tendency in average daily gain (ADG) and total superoxide dismutase (T-SOD) activity in serum, and T-SOD and glutathione peroxidase (GSH-Px) activities in the liver significantly decreased along with the appearance of AFB₁ and AFM₁ compared with those in Group C0. The supplementation of B. subtilis ANSB060 into aflatoxin-contaminated diets increased the ADG of ducks (p > 0.05), significantly improved antioxidant enzyme activities, and reduced aflatoxin accumulation in duck liver. In conclusion, Bacillus subtilis ANSB060 in diets showed an ameliorating effect to duck aflatoxicosis and may be a promising feed additive.

  14. Ameliorating Effects of Bacillus subtilis ANSB060 on Growth Performance, Antioxidant Functions, and Aflatoxin Residues in Ducks Fed Diets Contaminated with Aflatoxins

    PubMed Central

    Zhang, Liyuan; Ma, Qiugang; Ma, Shanshan; Zhang, Jianyun; Jia, Ru; Ji, Cheng; Zhao, Lihong

    2016-01-01

    Bacillus subtilis ANSB060 isolated from fish gut is very effective in detoxifying aflatoxins in feed and feed ingredients. The purpose of this research was to investigate the effects of B. subtilis ANSB060 on growth performance, body antioxidant functions, and aflatoxin residues in ducks fed moldy maize naturally contaminated with aflatoxins. A total of 1500 18-d-old male Cherry Valley ducks with similar body weight were randomly assigned to five treatments with six replicates of 50 ducks per repeat. The experiment design consisted of five dietary treatments labeled as C0 (basal diet containing 60% normal maize), M0 (basal diet containing 60% moldy maize contaminated with aflatoxins substituted for normal maize), M500, M1000, and M2000 (M0 +500, 1000 or 2000 g/t aflatoxin biodegradation preparation mainly consisted of B. subtilis ANSB060). The results showed that ducks fed 22.44 ± 2.46 μg/kg of AFB1 (M0) exhibited a decreasing tendency in average daily gain (ADG) and total superoxide dismutase (T-SOD) activity in serum, and T-SOD and glutathione peroxidase (GSH-Px) activities in the liver significantly decreased along with the appearance of AFB1 and AFM1 compared with those in Group C0. The supplementation of B. subtilis ANSB060 into aflatoxin-contaminated diets increased the ADG of ducks (p > 0.05), significantly improved antioxidant enzyme activities, and reduced aflatoxin accumulation in duck liver. In conclusion, Bacillus subtilis ANSB060 in diets showed an ameliorating effect to duck aflatoxicosis and may be a promising feed additive. PMID:28025501

  15. Intrauterine Exposure to Paracetamol and Aniline Impairs Female Reproductive Development by Reducing Follicle Reserves and Fertility.

    PubMed

    Holm, Jacob Bak; Mazaud-Guittot, Severine; Danneskiold-Samsøe, Niels Banhos; Chalmey, Clementine; Jensen, Benjamin; Nørregård, Mette Marie; Hansen, Cecilie Hurup; Styrishave, Bjarne; Svingen, Terje; Vinggaard, Anne Marie; Koch, Holger Martin; Bowles, Josephine; Koopman, Peter; Jégou, Bernard; Kristiansen, Karsten; Kristensen, David Møbjerg

    2016-03-01

    Studies report that fetal exposure to paracetamol/acetaminophen by maternal consumption can interfere with male reproductive development. Moreover, recent biomonitoring data report widespread presence of paracetamol in German and Danish populations, suggesting exposure via secondary (nonpharmaceutical) sources, such as metabolic conversion from the ubiquitous industrial compound aniline. In this study, we investigated the extent to which paracetamol and aniline can interfere with female reproductive development. Intrauterine exposure to paracetamol by gavage of pregnant dams resulted in shortening of the anogenital distance in adult offspring, suggesting that fetal hormone signaling had been disturbed. Female offspring of paracetamol-exposed mothers had ovaries with diminished follicle reserve and reduced fertility. Fetal gonads of exposed animals had also reduced gonocyte numbers, suggesting that the reduced follicle count in adults could be due to early disruption of germ cell development. However, ex vivo cultures of ovaries from 12.5 days post coitum fetuses showed no decrease in proliferation or expression following exposure to paracetamol. This suggests that the effect of paracetamol occurs prior to this developmental stage. Accordingly, using embryonic stem cells as a proxy for primordial germ cells we show that paracetamol is an inhibitor of cellular proliferation, but without cytotoxic effects. Collectively, our data show that intrauterine exposure to paracetamol at levels commonly observed in pregnant women, as well as its precursor aniline, may block primordial germ cell proliferation, ultimately leading to reduced follicle reserves and compromised reproductive capacity later in life.

  16. Determination of the Relative Effectiveness of Four Food Additives in Degrading Aflatoxin in Distillers Wet Grains and Condensed Distillers Solubles.

    PubMed

    Shi, H U; Stroshine, Richard L; Ileleji, Klein

    2017-01-01

    The food additives sodium bisulfite, sodium hypochlorite, citric acid, and ammonium persulfate were evaluated for their effectiveness in degrading aflatoxin in samples of distillers wet grains (DWG) and condensed distillers solubles (CDS) obtained from an industrial ethanol plant. Aqueous food additive solutions, 0.5% by weight, were added to DWG or CDS at the level of 0.5 ml/g of sample, and the materials were heated at 90°C for 1 h. Sodium bisulfite was not effective in degrading aflatoxin in either DWG or CDS. Among the four food additives tested, sodium hypochlorite was the most effective. However, it bleached the substrate and left an off-odor. Citric acid and ammonium persulfate reduced aflatoxin levels by 31 to 51%. Citric acid is the most promising additive for degrading aflatoxin because it has been classified as generally recognized as safe by the U.S. Food and Drug Administration. Aflatoxin reduction was enhanced by increasing the citric acid addition level and prolonging the heating time. Reductions of 65 and 80% in DWG and CDS, respectively, were obtained by the addition of 2.5% (by weight) citric acid and heating at 90°C for 1 h. Aflatoxin levels in DWG and CDS were gradually reduced with prolonged heating at 90°C, even without the addition of food additives. Aflatoxin reductions of 53 and 73% were achieved in DWG and CDS as a result of heating at 90°C for 5 h.

  17. Clinical interventions to reduce secondhand smoke exposure among pregnant women: a systematic review.

    PubMed

    Tong, Van T; Dietz, Patricia M; Rolle, Italia V; Kennedy, Sara M; Thomas, William; England, Lucinda J

    2015-05-01

    To conduct a systematic review of clinical interventions to reduce secondhand smoke (SHS) exposure among non-smoking pregnant women. We searched 16 databases for publications from 1990 to January 2013, with no language restrictions. Papers were included if they met the following criteria: (1) the study population included non-smoking pregnant women exposed to SHS, (2) the clinical interventions were intended to reduce SHS exposure at home, (3) the study included a control group and (4) outcomes included either reduced SHS exposure of non-smoking pregnant women at home or quit rates among smoking partners during the pregnancy of the woman. Two coders independently reviewed each abstract or full text to identify eligible papers. Two abstractors independently coded papers based on US Preventive Services Task Force criteria for study quality (good, fair, poor), and studies without biochemically-verified outcome measures were considered poor quality. From 4670 papers, we identified five studies that met our inclusion criteria: four focused on reducing SHS exposure among non-smoking pregnant women, and one focused on providing cessation support for smoking partners of pregnant women. All were randomised controlled trials, and all reported positive findings. Three studies were judged poor quality because outcome measures were not biochemically-verified, and two were considered fair quality. Clinical interventions delivered in prenatal care settings appear to reduce SHS exposure, but study weaknesses limit our ability to draw firm conclusions. More rigorous studies, using biochemical validation, are needed to identify strategies for reducing SHS exposure in pregnant women. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  18. Exposure to Herpes Simplex Virus, type 1 and reduced cognitive function

    PubMed Central

    Thomas, Pramod; Bhatia, Triptish; Gauba, Deepak; Wood, Joel; Long, Colleen; Prasad, Konasale; Dickerson, Faith B; Gur, Raquel E; Gur, Ruben C; Yolken, Robert H; Nimgaonkar, Vishwajit L; Deshpande, Smita N

    2013-01-01

    Herpes Simplex virus, type 1 (HSV-1) causes cold sores, keratitis and rarely, fatal encephalitis. The infection is life long, with sensory ganglia serving as reservoirs of latent infection. Recently, exposure to HSV-1 has also been repeatedly associated with reduced cognitive function among healthy individuals without prior encephalitis. Though HSV-1 does not elevate risk for schizophrenia (SZ) per se, exposure is likewise associated with impaired cognitive functions among SZ patients. The range of cognitive changes observed in HSV-1 exposed persons has not been investigated systematically, nor is it known whether interaction between HSV-1 exposure and SZ related factors contributes to the impairment among SZ patients. Persons with or without schizophrenia/schizophreniform disorder (N = 298 total, DSM IV criteria) were assessed for HSV-1 exposure using serum HSV-1 antibody titers. The Penn Computerized Neurocognitive battery was used to assess eight cognitive domains with respect to accuracy and speed. There were no significant case-control differences in HSV-1 exposure. The SZ/schizophreniform disorder cases were significantly impaired in all cognitive domains compared with the controls. HSV-1 exposure was also associated with reduced cognitive function in the entire sample, but the magnitude of the effects and their patterns differed from the SZ related changes. Further, statistically significant interactions between HSV-1 exposure and SZ case status were not detected. HSV-1 exposure does not elevate risk for SZ, but it is associated with reduced function in specific cognitive domains regardless of SZ diagnostic status. An ‘epidiagnostic’ model for the association is proposed to explain the results. PMID:23920011

  19. Atoxigenic strains of Aspergillus flavus isolated from peanuts collected from northern Philippines as potential biocon agents against pre-harvest aflatoxin contamination of peanut and corn

    USDA-ARS?s Scientific Manuscript database

    Aflatoxin contamination of food products causes liver cancer and weakened immunity in humans, and stunted growth and reduced productivity in animals (CAST, 2003). Effective control of pre-harvest aflatoxin contamination of peanut and corn due to AflaGuard and Aflasafe in the United States and Africa...

  20. The two genome sequence release and blast server construction for aflatoxin-producing L and S strains Aspergillus parasiticus and A. flavus

    USDA-ARS?s Scientific Manuscript database

    Aflatoxins are toxic and carcinogenic secondary metabolites. These compounds, produced by Aspergillus flavus and A. parasiticus, contaminate pre-harvest agricultural crops in the field and post-harvest grains during storage. In order to reduce and eliminate aflatoxin contamination of food and feed...

  1. Novel protective lead shield and pulse fluoroscopy can reduce radiation exposure during the ERCP procedure.

    PubMed

    Kurihara, Toshio; Itoi, Takao; Sofuni, Atsushi; Itokawa, Fumihide; Tsuchiya, Takayoshi; Ishii, Kentaro; Tsuji, Shujiro; Ikeuchi, Nobuhito; Moriyasu, Fuminori

    2012-05-01

    ERCP-related procedures involve radiation exposure of patients and medical staff. We developed a novel protective lead shield which is attached around the fluoroscopy generator. Here we examine levels of radiation exposure to patients, endoscopists and assistants, and evaluate the usefulness of the newly designed protective shield. Four-hundred and seventy-one ERCP procedures were performed from April 2006 to April 2007. At first, we compared the radiation dose of consecutive fluoroscopy conditions with pulse fluoroscopy of 15 per second and then the radiation dose with and without the protective shield. Next, we measured the radiation exposure of endoscopists and assistants in the clinical setting monitored by digital dosimeter during ERCP procedure. The radiation dose was the most at the 45° direction. Using pulse fluoroscopy of 15 per second the radiation dose of patients and endoscopists decreased by about half. Using both pulse fluoroscopy of 15 per second and the protective shield, the radiation dose at the endoscopist's position was reduced up to 97%. The total fluoroscopy time was 5851 minutes in the 471 ERCP cases. Using pulse 15 and the protective lead shield, the radiation exposure dose of one endoscopist and two assistants were 2430.8, 2673.9 and 1375.0µSv, respectively. Novel protective lead shield in combination with pulse fluoroscopy can significantly reduce the radiation exposure leading to avoid unnecessary radiation exposure to patients and medical staff.

  2. Exposure reduces negative bias in self-rated performance in public speaking fearful participants.

    PubMed

    Cheng, Joyce; Niles, Andrea N; Craske, Michelle G

    2017-03-01

    Individuals with public speaking anxiety (PSA) under-rate their performance compared to objective observers. The present study examined whether exposure reduces the discrepancy between self and observer performance ratings and improved observer-rated performance in individuals with PSA. PSA participants gave a speech in front of a small audience and rated their performance using a questionnaire before and after completing repeated exposures to public speaking. Non-anxious control participants gave a speech and completed the questionnaire one time only. Objective observers watched videos of the speeches and rated performance using the same questionnaire. PSA participants underrated their performance to a greater degree than did controls prior to exposure, but also performed significantly more poorly than did controls when rated objectively. Bias significantly decreased and objective-rated performance significantly increased following completion of exposure in PSA participants, and on one performance measure, anxious participants no longer showed a greater discrepancy between self and observer performance ratings compared to controls. The study employed non-clinical student sample, but the results should be replicated in clinical anxiety samples. These findings indicate that exposure alone significantly reduces negative performance bias among PSA individuals, but additional exposure or additional interventions may be necessary to fully correct bias and performance deficits. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. CHRONIC INTERMITTENT ETHANOL EXPOSURE REDUCES PRESYNAPTIC DOPAMINE NEUROTRANSMISSION IN THE MOUSE NUCLEUS ACCUMBENS

    PubMed Central

    Karkhanis, Anushree N.; Rose, Jamie H.; Huggins, Kimberly N.; Konstantopoulos, Joanne K.; Jones, Sara R.

    2015-01-01

    BACKGROUND Increasing evidence suggests that chronic ethanol exposure decreases dopamine (DA) neurotransmission in the nucleus accumbens (NAc), contributing to a hypodopaminergic state during withdrawal. However, few studies have investigated adaptations in presynaptic DA terminals after chronic intermittent ethanol (CIE) exposure. In monkeys and rats, chronic ethanol exposure paradigms have been shown to increase DA uptake and D2 autoreceptor sensitivity. METHODS The current study examined the effects of ethanol on DA terminals in CIE exposed mice during two time-points after the cessation of CIE exposure. DA release and uptake were measured using fast scan cyclic voltammetry in NAc core slices from C57BL/6J mice, 0 and 72 hours following three weekly cycles (4 days of 16 hrs ethanol vapor/8 hrs room air/day + 3 days withdrawal) of CIE vapor exposure. RESULTS Current results showed that DA release was reduced, uptake rates were increased, and inhibitory D2-type autoreceptor activity was augmented following CIE exposure in mice. CONCLUSIONS Overall, these CIE-induced adaptations in the accumbal DA system reduce DA signaling and therefore reveal several potential mechanisms contributing to a functional hypodopaminergic state during alcohol withdrawal. PMID:25765483

  4. Chronic intermittent ethanol exposure reduces presynaptic dopamine neurotransmission in the mouse nucleus accumbens.

    PubMed

    Karkhanis, Anushree N; Rose, Jamie H; Huggins, Kimberly N; Konstantopoulos, Joanne K; Jones, Sara R

    2015-05-01

    Increasing evidence suggests that chronic ethanol exposure decreases dopamine (DA) neurotransmission in the nucleus accumbens (NAc), contributing to a hypodopaminergic state during withdrawal. However, few studies have investigated adaptations in presynaptic DA terminals after chronic intermittent ethanol (CIE) exposure. In monkeys and rats, chronic ethanol exposure paradigms have been shown to increase DA uptake and D2 autoreceptor sensitivity. The current study examined the effects of ethanol on DA terminals in CIE exposed mice during two time-points after the cessation of CIE exposure. DA release and uptake were measured using fast scan cyclic voltammetry in NAc core slices from C57BL/6J mice, 0h and 72h following three weekly cycles (4 days of 16h ethanol vapor/8h room air/day+3 days withdrawal) of CIE vapor exposure. Current results showed that DA release was reduced, uptake rates were increased, and inhibitory D2-type autoreceptor activity was augmented following CIE exposure in mice. Overall, these CIE-induced adaptations in the accumbal DA system reduce DA signaling and therefore reveal several potential mechanisms contributing to a functional hypodopaminergic state during alcohol withdrawal. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  5. Effects of Tarantula cubensis D6 on aflatoxin-induced injury in biochemical parameters in rats.

    PubMed

    Karabacak, Mürsel; Eraslan, Gökhan; Kanbur, Murat; Sarıca, Zeynep Soyer

    2015-07-01

    Aflatoxins are toxic fungal metabolites that have adverse effects on humans and animals. Tarantula cubensis D6 is used as a homeopathic medicine for different purposes. The present study investigates the effects of Tarantula cubensis D6 on the oxidant-antioxidant balance and some biochemical parameters against exposure to aflatoxin. Thirty-two Sprague-Dawley female rats were used and evenly divided into four groups. Group 1 served as control. Groups 2, 3, and 4 received 200 μl/kg.bw/day Tarantula cubensis D6 (applied subcutaneously), 400 μg/kg.bw/day total aflatoxin (approximately 80% AF B1, 10% AF B2, 6 %AF G1, and 4% AF G2), and 200 μl/kg.bw/day Tarantula cubensis D6 plus 400 μg/kg.bw/day total aflatoxin, respectively, for 28 days. At the end of 28 days, blood samples and some organs (liver, kidney, brain, and spleen) were taken from all the animals. Oxidative stress markers (MDA, SOD, CAT, GSH-Px) and some biochemical parameters (glucose, triglyceride, cholesterol, BUN, creatinine, AST, ALT and ALP, total protein, albumin) were evaluated in blood samples and tissues. Aflatoxin caused negative changes in all oxidative stress parameters and some biochemical parameters (glucose, triglyceride, cholesterol, creatinine, AST, ALT, ALP, total protein, albumin). Administration of Tarantula cubensis D6 partly alleviated aflatoxin-induced negative changes. Our results indicated that Tarantula cubensis D6 partially neutralized the deleterious effects of aflatoxin. Copyright © 2015 The Faculty of Homeopathy. Published by Elsevier Ltd. All rights reserved.

  6. Comparison of cultural and analytical methods for determination of aflatoxin production by Mississippi Delta Aspergillus isolates.

    PubMed

    Abbas, Hamed K; Zablotowicz, R M; Weaver, M A; Horn, B W; Xie, W; Shier, W T

    2004-03-01

    This study compared cultural and analytical methods for detecting aflatoxin production by Aspergillus species. Aspergillus isolates were obtained from various Mississippi Delta crops (corn, peanut, rice, cotton) and soils. Most of the isolates (99%) were A. flavus and the remainder comprised A. parasiticus and A. nomius. The following three cultural methods were evaluated on potato dextrose agar: fluorescence (FL) on beta-cyclodextrin-containing media (CD), yellow pigment (YP) formation in mycelium and medium, and color change after ammonium hydroxide vapor exposure (AV). Aflatoxins in culture extracts were confirmed by thin-layer chromatography (TLC) and quantified by enzyme-linked immunosorbent assay (ELISA). Of the 517 isolates, 314 produced greater than 20 ng/g of total aflatoxin based on ELISA, and 180 produced greater than 10 000 ng/g of aflatoxin in the medium. Almost all the toxigenic isolates (97%) were confirmed by TLC as producers. Of the toxigenic isolates, as determined by ELISA, 93%, 73%, and 70% gave positive FL, YP, and AV responses, respectively. Of the 203 isolates producing less than 20 ng/g of aflatoxin, 20%, 6%, and 0% of respective FL, YP, and AV methods gave false-positive responses. The 9% false-positive results from TLC fall within this range. This study showed good agreement among all tested cultural methods. However, these cultural techniques did not detect aflatoxin in all cultures that were found to produce aflatoxins by ELISA, LC/MS, and TLC. The best results were obtained when the AV color change and CD fluorescence methods were used together, yielding an overall success rate comparable to TLC but without the need for chemical extraction and the time and expense of TLC.

  7. Non-aflatoxigenic Aspergillus flavus to prevent aflatoxin contamination in crops: advantages and limitations.

    PubMed

    Ehrlich, Kenneth C

    2014-01-01

    Aspergillus flavus is a diverse assemblage of strains that include aflatoxin-producing and non-toxigenic strains with cosmopolitan distribution. The most promising strategy currently being used to reduce preharvest contamination of crops with aflatoxin is to introduce non-aflatoxin (biocontrol) A. flavus into the crop environment. Whether or not introduction of biocontrol strains into agricultural fields is enough to reduce aflatoxin contamination to levels required for acceptance of the contaminated food as fit for consumption is still unknown. There is no question that biocontrol strains are able to reduce the size of the populations of aflatoxin-producing strains but the available data suggests that at most only a four- to five-fold reduction in aflatoxin contamination is achieved. There are many challenges facing this strategy that are both short term and long term. First, the population biology of A. flavus is not well understood due in part to A. flavus's diversity, its ability to form heterokaryotic reproductive forms, and its unknown ability to survive for prolonged periods after application. Second, biocontrol strains must be selected that are suitable for the environment, the type of crop, and the soil into which they will be introduced. Third, there is a need to guard against inadvertent introduction of A. flavus strains that could impose an additional burden on food safety and food quality, and fourth, with global warming and resultant changes in the soil nutrients and concomitant microbiome populations, the biocontrol strategy must be sufficiently flexible to adapt to such changes. Understanding genetic variation within strains of A. flavus is important for developing a robust biocontrol strategy and it is unlikely that a "one size fits all" strategy will work for preharvest aflatoxin reduction.

  8. Non-aflatoxigenic Aspergillus flavus to prevent aflatoxin contamination in crops: advantages and limitations

    PubMed Central

    Ehrlich, Kenneth C.

    2014-01-01

    Aspergillus flavus is a diverse assemblage of strains that include aflatoxin-producing and non-toxigenic strains with cosmopolitan distribution. The most promising strategy currently being used to reduce preharvest contamination of crops with aflatoxin is to introduce non-aflatoxin (biocontrol) A. flavus into the crop environment. Whether or not introduction of biocontrol strains into agricultural fields is enough to reduce aflatoxin contamination to levels required for acceptance of the contaminated food as fit for consumption is still unknown. There is no question that biocontrol strains are able to reduce the size of the populations of aflatoxin-producing strains but the available data suggests that at most only a four- to five-fold reduction in aflatoxin contamination is achieved. There are many challenges facing this strategy that are both short term and long term. First, the population biology of A. flavus is not well understood due in part to A. flavus’s diversity, its ability to form heterokaryotic reproductive forms, and its unknown ability to survive for prolonged periods after application. Second, biocontrol strains must be selected that are suitable for the environment, the type of crop, and the soil into which they will be introduced. Third, there is a need to guard against inadvertent introduction of A. flavus strains that could impose an additional burden on food safety and food quality, and fourth, with global warming and resultant changes in the soil nutrients and concomitant microbiome populations, the biocontrol strategy must be sufficiently flexible to adapt to such changes. Understanding genetic variation within strains of A. flavus is important for developing a robust biocontrol strategy and it is unlikely that a “one size fits all” strategy will work for preharvest aflatoxin reduction. PMID:24575088

  9. Complete protection against aflatoxin B(1)-induced liver cancer with a triterpenoid: DNA adduct dosimetry, molecular signature, and genotoxicity threshold.

    PubMed

    Johnson, Natalie M; Egner, Patricia A; Baxter, Victoria K; Sporn, Michael B; Wible, Ryan S; Sutter, Thomas R; Groopman, John D; Kensler, Thomas W; Roebuck, Bill D

    2014-07-01

    In experimental animals and humans, aflatoxin B1 (AFB1) is a potent hepatic toxin and carcinogen. The synthetic oleanane triterpenoid 1-[2-cyano-3-,12-dioxooleana-1,9(11)-dien-28-oyl]imidazole (CDDO-Im), a powerful activator of Keap1-Nrf2 signaling, protects against AFB1-induced toxicity and preneoplastic lesion formation (GST-P-positive foci). This study assessed and mechanistically characterized the chemoprotective efficacy of CDDO-Im against AFB1-induced hepatocellular carcinoma (HCC). A lifetime cancer bioassay was undertaken in F344 rats dosed with AFB1 (200 μg/kg rat/day) for four weeks and receiving either vehicle or CDDO-Im (three times weekly), one week before and throughout the exposure period. Weekly, 24-hour urine samples were collected for analysis of AFB1 metabolites. In a subset of rats, livers were analyzed for GST-P foci. The comparative response of a toxicogenomic RNA expression signature for AFB1 was examined. CDDO-Im completely protected (0/20) against AFB1-induced liver cancer compared with a 96% incidence (22/23) observed in the AFB1 group. With CDDO-Im treatment, integrated level of urinary AFB1-N(7)-guanine was significantly reduced (66%) and aflatoxin-N-acetylcysteine, a detoxication product, was consistently elevated (300%) after the first AFB1 dose. In AFB1-treated rats, the hepatic burden of GST-P-positive foci increased substantially (0%-13.8%) over the four weeks, but was largely absent with CDDO-Im intervention. The toxicogenomic RNA expression signature characteristic of AFB1 was absent in the AFB1 + CDDO-Im-treated rats. The remarkable efficacy of CDDO-Im as an anticarcinogen is established even in the face of a significant aflatoxin adduct burden. Consequently, the absence of cancer requires a concept of a threshold for DNA damage for cancer development. ©2014 American Association for Cancer Research.

  10. Exposure to inhaled isobutyl nitrite reduces T cell-dependent responsiveness

    SciTech Connect

    Soderberg, L.S.F.; Barnett, J.B. )

    1991-03-11

    Isobutyl nitrite is a drug of abuse popular among male homosexuals and among adolescents. In order to approximate the nitrite exposures of inhalant abusers, mice were treated with 900 ppm isobutyl nitrite in an inhalation chamber for 45 min per day for 14 days. At 72 hr after the last exposure, mice were assayed for immune competence. Under these conditions, mice gained only half the weight of mice exposed to air. The spleens of nitrite exposed mice weighed 15% less and had 24% fewer cells per spleen than controls. Adjusted for equal cell numbers, T cell mitogenic and allogeneic proliferative responses were significantly reduce by 33% and 47%, respectively. Unstimulated spleen cells had elevated levels of IL-2 transcription following exposure to isobutyl nitrite suggesting that nitrite inhalation caused a nonspecific induction of T cells. In contrast, B cell proliferative responses to LPS were unaltered. Exposure to the nitrite reduced the frequency of T-dependent antibody plaque-forming cells (PFC) by 63% and the total number of reduced by 60% after as few as five daily exposures to isobutyl nitrite. Therefore, the data suggest that habitual inhalation of isobutyl nitrite impairs immune competence and that toxicity appears to be directed toward T cell functions.

  11. Occurrence of aflatoxins in selected colombian foods.

    PubMed

    Diaz, G; Perilla, N; Rojas, Y

    2001-03-01

    A survey of aflatoxin contamination in selected Colombian foods was conducted over a 12-month period on a total of 248 samples. Samples were collected in supermarkets, retail stores and stock centres and were grouped into five categories: (1) corn and corn products, (2) cereal grains, (3) rice and rice products, (4) legume seeds; and (5) snacks and breakfast cereals. Aflatoxins were identified and quantitated using a liquid chromatographic technique with a limit of detection of 1 ng/g for each aflatoxin. Aflatoxins were detected in 14 of 109 samples of corn and corn products, 4 of 40 samples of rice and rice products, 2 of 30 samples of legume seeds, and 2 of 11 samples of snacks and breakfast cereals. None of the cereal grains samples analysed contained detectable levels of aflatoxins. Twelve of the total of 22 positive samples exceeded the maximum tolerable level of aflatoxin B1 adopted in most countries (5 ng/g); 10 of these 12 samples corresponded to corn and corn products. The results of the present study indicate that aflatoxin B1 contamination in certain foods in Colombia is a major public health concern. Continuous monitoring of aflatoxin B1 levels in Colombian foods is advised.

  12. Computational search for aflatoxin binding proteins

    NASA Astrophysics Data System (ADS)

    Wang, Ying; Liu, Jinfeng; Zhang, Lujia; He, Xiao; Zhang, John Z. H.

    2017-10-01

    Aflatoxin is one of the mycotoxins that contaminate various food products. Among various aflatoxin types (B1, B2, G1, G2 and M1), aflatoxin B1 is the most important and the most toxic one. In this study, through computational screening, we found that several proteins may bind specifically with different type of aflatoxins. Combination of theoretical methods including target fishing, molecular docking, molecular dynamics (MD) simulation, MM/PBSA calculation were utilized to search for new aflatoxin B1 binding proteins. A recently developed method for calculating entropic contribution to binding free energy called interaction entropy (IE) was employed to compute the binding free energy between the protein and aflatoxin B1. Through comprehensive comparison, three proteins, namely, trihydroxynaphthalene reductase, GSK-3b, and Pim-1 were eventually selected as potent aflatoxin B1 binding proteins. GSK-3b and Pim-1 are drug targets of cancers or neurological diseases. GSK-3b is the strongest binder for aflatoxin B1.

  13. Aflatoxin biosynthetic pathway and pathway genes

    USDA-ARS?s Scientific Manuscript database

    Aspergillus flavus is the most economically important because it produces the toxic and carcinogenic aflatoxins. A. flavus fungus is capable of surviving on many organic nutrient sources and is one of the most abundant soil-borne molds on earth. Aflatoxins were first identified in 1960. Over the la...

  14. Separation of aflatoxins from filter cake

    SciTech Connect

    Ogawa, I.; Chriswell, C.D.

    1982-02-01

    Size-exclusion chromatography using silianized porous silica microspheres is used to clean up an environmental sample prior to aflatoxin analysis. B/sub 1/ and B/sub 2/ aflatoxins were found in an anaerobic digestor filter cake sample at concentrations of 1 ppb.

  15. Co-occurence of aflatoxins and fumonisins in maize: guatemala as a case study

    USDA-ARS?s Scientific Manuscript database

    Aflatoxin B1 (AFB1) and fumonisin B1 (FB1) are found in maize. AFB1 is a genotoxic carcinogen (IARC Group 1) and FB1 a liver cancer promoter in rodents and trout (IARC Group 2B). Therefore, the possibility of co-exposure is a health concern, most notably in areas where maize serves as a dietary st...

  16. Effect of dietary acids on the formation of aflatoxin B2a as a means to detoxify aflatoxin B1.

    PubMed

    Rushing, Blake R; Selim, Mustafa I

    2016-09-01

    Aflatoxin B1 (AFB1) is a class 1 carcinogen and a common food contaminant worldwide with widely uncontrolled human exposure. The ability of organic acids to transform AFB1 into a known detoxified form, aflatoxin B2a (AFB2a), was investigated using high performance liquid chromatography-electrospray ionisation-time of flight mass spectrometry (HPLC/ESI/TOF/MS). The identity of the transformation product was confirmed by accurate mass measurement, chromatographic separation from other aflatoxins, H(1)-nuclear magnetic resonance (NMR) and infrared (IR) spectroscopy. Of the weak acids tested, citric acid was found to be the most effective for AFB2a formation. At room temperature, 1 M citric acid was able to convert > 97% of AFB1 to AFB2a over 96 h of treatment. Up to 98% transformation was achieved by boiling AFB1 in the presence of citric acid for 20 min. AFB1 hydration after ingestion was explored by spiking AFB1 into simulated gastric fluid containing citric acid. Under these conditions, > 71% of AFB1 was hydrated to AFB2a and did not show any reversion to the parent compound after being transferred to a neutral solution. These results provide a basis for a practical and effective method for detoxification of AFB1 in contaminated foods.

  17. Environmental Tobacco Smoke Exposure in Pregnancy is Associated With Earlier Delivery and Reduced Birth Weight.

    PubMed

    Ion, Rachel C; Wills, Andrew K; Bernal, Andrés López

    2015-12-01

    The association between maternal smoking and preterm birth (PTB) has been known for more than 50 years but the effect of passive smoking is controversial. This retrospective cohort study in Bristol, United Kingdom, examines the effect of environmental tobacco smoke exposure (ETSE) on gestational age at delivery, birth weight, PTB, and being small-for-gestational age (SGA). Environmental tobacco smoke exposure was defined by either self-report or exhaled carbon monoxide (eCO) levels, and exposed women were compared with unexposed controls. Two models were used: The first included all women with adjustment for maternal smoking, and the second considered nonsmokers alone. Both models were further adjusted for maternal age, body mass index, parity, ethnicity, employment status, socioeconomic position, asthma, preeclampsia, and offspring sex. Logistic regression and likelihood ratio tests were used to test for any association between exposure and the binary outcomes (PTB and SGA), while linear regression and F tests were used to test for associations between exposure and the continuous outcomes. There were 13 359 deliveries in 2012 to 2014, with complete data for 5066 and 4793 women in the self-reported and eCO-measured exposure groups, respectively. Self-reported exposure was associated with earlier delivery (-0.19 weeks; 95% confidence interval [CI]: -0.32 to -0.05) and reduced birth weight (-56 g, 95% CI: -97 to -16 g) but no increase in the risk of PTB or SGA. There was no evidence for an association between eCO-measured exposure and any of the outcome measures. This information is important when advising women and their families and adds further support to continued public health efforts to reduce exposure to tobacco smoke.

  18. An old/new idea for reducing exposure to x-rays

    SciTech Connect

    Colquitt, W.N.; Richards, A.G.

    1982-11-01

    In 1925 the patient's exposure to x-radiation was reduced 50 percent by the application of emulsion to both sides of the dental film. Another similar reduction is possible when the layers of emulsion are once again doubled. The authors have rediscovered this idea and tested it. A double film packet containing films which are hinged on one side for proper reorientation after developing was produced. The films were exposed to half the radiation given to normal packets. It was found that density, contrast, and definition were all comparable to normal exposures when allowances were made for an additional layer of blue-tinted film base. In addition to reduced exposure to x-rays, the folded-film technique gives a second view of the exposed area. An underexposed view is obtained by viewing either side of the folded film alone. This underexposed view offers some details not seen on fully exposed films.

  19. Evening ambient light exposure can reduce circadian phase advances to morning light independent of sleep deprivation

    PubMed Central

    Burgess, Helen J.

    2013-01-01

    SUMMARY Short sleep/dark durations are common in modern society. We investigated if exposure to additional evening ambient light, often associated with later bedtimes and short sleep, reduces circadian phase advances to morning bright light. Twelve healthy subjects participated in two conditions that differed in the distribution of sleep before exposure to morning bright light. Subjects had a consolidated 9-h night time sleep opportunity, or a 3-h daytime nap followed by a 6-h night time sleep opportunity, each before morning bright light. Eight of the 12 subjects obtained similar amounts of sleep in both conditions, and yet still showed significant reductions in phase advances with 6-h nights (1.7 versus 0.7 h, P < 0.05). These results suggest that the exposure to additional evening ambient light often associated with short sleep episodes can significantly reduce phase advances to morning light, and may therefore increase the risk for circadian misalignment. PMID:22889464

  20. Aflatoxin contamination in food commodities in Bangladesh.

    PubMed

    Roy, Monika; Harris, Julie; Afreen, Sadia; Deak, Eszter; Gade, Lalitha; Balajee, S Arunmozhi; Park, Benjamin; Chiller, Tom; Luby, Stephen

    2013-01-01

    During September 2009, we performed a rapid cross-sectional study to investigate the extent of aflatoxin contamination among common Bangladeshi foods. We collected eight common human food commodities (rice, lentils, wheat flour, dates, betelnut, red chili powder, ginger and groundnuts) and poultry feed samples from two large markets in each of three cities in Bangladesh. We quantified aflatoxin levels from pooled subsamples using fluorescence high-performance liquid chromatography. Aflatoxin levels were highest in dates and groundnuts (maximum 623 and 423 ng/g), respectively. Samples of betelnut (mean 30.6 ng/g), lentils (mean 21.2 ng/g) and red chili powder (>20 ng/g) also had elevated levels. The mean aflatoxin level among poultry feed samples was 73.0 ng/g. Aflatoxin levels were above the US maximum regulatory levels of 20 ng/g in five of eight commonly ingested human food commodities tested.

  1. Prolonged head-down tilt exposure reduces maximal cutaneous vasodilator and sweating capacity in humans

    NASA Technical Reports Server (NTRS)

    Crandall, C. G.; Shibasaki, M.; Wilson, T. E.; Cui, J.; Levine, B. D.

    2003-01-01

    Cutaneous vasodilation and sweat rate are reduced during a thermal challenge after simulated and actual microgravity exposure. The effects of microgravity exposure on cutaneous vasodilator capacity and on sweat gland function are unknown. The purpose of this study was to test the hypothesis that simulated microgravity exposure, using the 6 degrees head-down tilt (HDT) bed rest model, reduces maximal forearm cutaneous vascular conductance (FVC) and sweat gland function and that exercise during HDT preserves these responses. To test these hypotheses, 20 subjects were exposed to 14 days of strict HDT bed rest. Twelve of those subjects exercised (supine cycle ergometry) at 75% of pre-bed rest heart rate maximum for 90 min/day throughout HDT bed rest. Before and after HDT bed rest, maximal FVC was measured, via plethysmography, by heating the entire forearm to 42 degrees C for 45 min. Sweat gland function was assessed by administering 1 x 10(-6) to 2 M acetylcholine (9 doses) via intradermal microdialysis while simultaneously monitoring sweat rate over the microdialysis membranes. In the nonexercise group, maximal FVC and maximal stimulated sweat rate were significantly reduced after HDT bed rest. In contrast, these responses were unchanged in the exercise group. These data suggest that 14 days of simulated microgravity exposure, using the HDT bed rest model, reduces cutaneous vasodilator and sweating capacity, whereas aerobic exercise training during HDT bed rest preserves these responses.

  2. Prolonged head-down tilt exposure reduces maximal cutaneous vasodilator and sweating capacity in humans

    NASA Technical Reports Server (NTRS)

    Crandall, C. G.; Shibasaki, M.; Wilson, T. E.; Cui, J.; Levine, B. D.

    2003-01-01

    Cutaneous vasodilation and sweat rate are reduced during a thermal challenge after simulated and actual microgravity exposure. The effects of microgravity exposure on cutaneous vasodilator capacity and on sweat gland function are unknown. The purpose of this study was to test the hypothesis that simulated microgravity exposure, using the 6 degrees head-down tilt (HDT) bed rest model, reduces maximal forearm cutaneous vascular conductance (FVC) and sweat gland function and that exercise during HDT preserves these responses. To test these hypotheses, 20 subjects were exposed to 14 days of strict HDT bed rest. Twelve of those subjects exercised (supine cycle ergometry) at 75% of pre-bed rest heart rate maximum for 90 min/day throughout HDT bed rest. Before and after HDT bed rest, maximal FVC was measured, via plethysmography, by heating the entire forearm to 42 degrees C for 45 min. Sweat gland function was assessed by administering 1 x 10(-6) to 2 M acetylcholine (9 doses) via intradermal microdialysis while simultaneously monitoring sweat rate over the microdialysis membranes. In the nonexercise group, maximal FVC and maximal stimulated sweat rate were significantly reduced after HDT bed rest. In contrast, these responses were unchanged in the exercise group. These data suggest that 14 days of simulated microgravity exposure, using the HDT bed rest model, reduces cutaneous vasodilator and sweating capacity, whereas aerobic exercise training during HDT bed rest preserves these responses.

  3. A Behavioral Intervention to Reduce Child Exposure to Indoor Air Pollution: Identifying Possible Target Behaviors

    ERIC Educational Resources Information Center

    Barnes, Brendon R.; Mathee, Angela; Shafritz, Lonna B.; Krieger, Laurie; Zimicki, Susan

    2004-01-01

    Indoor air pollution has been causally linked to acute lower respiratory infections in children younger than 5. The aim of this study was to identify target behaviors for a behavioral intervention to reduce child exposure to indoor air pollution by attempting to answer two research questions: Which behaviors are protective of child respiratory…

  4. Precocious glucocorticoid exposure reduces skeletal muscle satellite cells in the fetal rat

    USDA-ARS?s Scientific Manuscript database

    Perinatal skeletal muscle growth rates are a function of protein and myonuclear accretion. Precocious exposure of the fetus to glucocorticoids (GLC) in utero impairs muscle growth. Reduced muscle protein synthesis rates contribute to this response, but the consequences for myonuclear hyperplasia are...

  5. Using Behavior Change to Reduce Child Lead Exposure in Resource-Poor Settings: A Formative Study

    ERIC Educational Resources Information Center

    Feit, M. N.; Mathee, A.; Harpham, T.; Barnes, B. R.

    2014-01-01

    The objective of this formative research was to explore the acceptability and feasibility of changing housekeeping behaviors as a low-cost approach that may reduce childhood lead exposure in Johannesburg, South Africa. Using the Trials of Improved Practices (TIPs) methodology, modified housekeeping behaviors were negotiated with participants who…

  6. Efflux of reduced glutathione after exposure of human lung epithelial cells to crocidolite asbestos.

    PubMed Central

    Golladay, S A; Park, S H; Aust, A E

    1997-01-01

    This study investigated glutathione (GSH) homeostasis in human lung epithelial cells (A549) exposed to crocidolite. Exposure of A549 cells to 3 micrograms/cm2 crocidolite resulted in a decrease in intracellular reduced glutathione by 36% without a corresponding increase in GSH disulfide. After a 24-hr exposure to crocidolite, 75% of the intracellular GSH lost was recovered in the extracellular medium, of which 50% was in reduced form. Since the half-life of reduced GSH in culture medium was less than 1 hr, this suggests that reduced GSH was released continuously from the cells after treatment. The release of GSH did not appear to result from nonspecific membrane damage, as there was no concomitant release of lactate dehydrogenase or 14C-adenine from loaded cells after crocidolite treatment for 24 hr. Crocidolite exposure resulted in the formation of S-nitrosothiols but no increase in the level of GSH-protein mixed disulfides or GSH conjugates. Exposure of A549 cells to crocidolite for 24 hr decreased gamma glutamylcysteine synthetase (gamma-GCS) activity by 47% without changes in the activities of GSH reductase, GSH peroxidase, GSH S-transferase, or glucose-6-phosphate dehydrogenase. Treatment of cells with crocidolite pretreated with the iron chelator desferrioxamine B resulted in the same level of intracellular GSH depletion and efflux and the same decrease in gamma-GCS activity as treatment with unmodified crocidolite, which suggests that iron-catalyzed reactions were not responsible for the GSH depletion. PMID:9400737

  7. Reducing Children's Implicit Racial Bias through Exposure to Positive Out-Group Exemplars

    ERIC Educational Resources Information Center

    Gonzalez, Antonya M.; Steele, Jennifer R.; Baron, Andrew S.

    2017-01-01

    Studies with adults suggest that implicit preferences favoring White versus Black individuals can be reduced through exposure to positive Black exemplars. However, it remains unclear whether developmental differences exist in the capacity for these biases to be changed. This study included 369 children and examined whether their implicit racial…

  8. A Behavioral Intervention to Reduce Child Exposure to Indoor Air Pollution: Identifying Possible Target Behaviors

    ERIC Educational Resources Information Center

    Barnes, Brendon R.; Mathee, Angela; Shafritz, Lonna B.; Krieger, Laurie; Zimicki, Susan

    2004-01-01

    Indoor air pollution has been causally linked to acute lower respiratory infections in children younger than 5. The aim of this study was to identify target behaviors for a behavioral intervention to reduce child exposure to indoor air pollution by attempting to answer two research questions: Which behaviors are protective of child respiratory…

  9. Hazardous Chemicals on the Job: A Workers Guide to Reducing Exposure.

    ERIC Educational Resources Information Center

    Conrad, Fran; Kayman, Lindsey

    This guide is intended to assist workers in reducing their exposure to hazardous chemicals on the job. It describes a systematic preventive approach to hazardous chemicals that is based on the following steps: determining which chemicals are in use at a particular worksite (techniques for asking the company and steps to take if the company is…

  10. Using Behavior Change to Reduce Child Lead Exposure in Resource-Poor Settings: A Formative Study

    ERIC Educational Resources Information Center

    Feit, M. N.; Mathee, A.; Harpham, T.; Barnes, B. R.

    2014-01-01

    The objective of this formative research was to explore the acceptability and feasibility of changing housekeeping behaviors as a low-cost approach that may reduce childhood lead exposure in Johannesburg, South Africa. Using the Trials of Improved Practices (TIPs) methodology, modified housekeeping behaviors were negotiated with participants who…

  11. U.S. EPA Resource Helps Schools Reduce Exposure to Traffic-Related Air Pollution

    EPA Pesticide Factsheets

    LOS ANGELES--The U.S. Environmental Protection Agency released a document to give schools and parents ideas on how to reduce children's exposure to traffic-related air pollution. When schools are located close to busy roads, students can be exposed to unhe

  12. A Community-Based Initiative to Reduce Children's Exposure to Toxics in Household Products

    ERIC Educational Resources Information Center

    Blackman, Anne Berlin; Luskin, Jack

    2006-01-01

    Purpose--The purpose of this paper is to explore the efficacy of a community-based outreach initiative, piloted in Worcester, Massachusetts, to reduce children's exposure to toxic chemicals in common household products by changing parental behavior regarding product purchase and use. Design/methodology/approach--The program model was based on the…

  13. For a healthier future: a virtuous cycle for reducing exposure to persistent organic pollutants

    PubMed Central

    Mori, Chisato; Todaka, Emiko

    2017-01-01

    In the modern society, people are exposed to various pollutants during their lifetime. Worldwide, the status of children's health has changed in recent decades. Some studies have attempted to identify the causes of these changes and whether they relate to pollutant exposure; however, such attempts have faced major challenges because human life is complex, involving many social and environmental factors. Several long-term cohort studies are being conducted to determine the relationship between diseases and social and environmental factors in children. Even before we establish complete proof of adverse effects, we should attempt to decrease risk to future generations by adopting precautionary principles. Environmental exposure to persistent organic pollutants can be reduced throughout the stages of life—the fetal period, newborn and infant periods, childhood, adolescence and adulthood (preconception) by individuals as well as by society as a whole. Through reducing environmental exposure to pollutants, adverse health effects can also be reduced, which will contribute to healthier future generations. Here, we suggest a virtuous cycle for improving the health of future generations through reduced exposure to persistent pollutants. PMID:28515209

  14. Perceptual Individuation Training (but Not Mere Exposure) Reduces Implicit Racial Bias in Preschool Children

    ERIC Educational Resources Information Center

    Qian, Miao K.; Quinn, Paul C.; Heyman, Gail D.; Pascalis, Olivier; Fu, Genyue; Lee, Kang

    2017-01-01

    Two studies with preschool-age children examined the effectiveness of perceptual individuation training at reducing racial bias (Study 1, N = 32; Study 2, N = 56). We found that training preschool-age children to individuate other-race faces resulted in a reduction in implicit racial bias while mere exposure to other-race faces produced no such…

  15. A Community-Based Initiative to Reduce Children's Exposure to Toxics in Household Products

    ERIC Educational Resources Information Center

    Blackman, Anne Berlin; Luskin, Jack

    2006-01-01

    Purpose--The purpose of this paper is to explore the efficacy of a community-based outreach initiative, piloted in Worcester, Massachusetts, to reduce children's exposure to toxic chemicals in common household products by changing parental behavior regarding product purchase and use. Design/methodology/approach--The program model was based on the…

  16. The inhibitory effect of Bacillus megaterium on aflatoxin and cyclopiazonic acid biosynthetic pathway gene expression in Aspergillus flavus.

    PubMed

    Kong, Qing; Chi, Chen; Yu, Jiujiang; Shan, Shihua; Li, Qiyu; Li, Qianting; Guan, Bin; Nierman, William C; Bennett, Joan W

    2014-06-01

    Aspergillus flavus is one of the major moulds that colonize peanut in the field and during storage. The impact to human and animal health, and to the economy in agriculture and commerce, is significant since this mold produces the most potent known natural toxins, aflatoxins, which are carcinogenic, mutagenic, immunosuppressive, and teratogenic. A strain of marine Bacillus megaterium isolated from the Yellow Sea of East China was evaluated for its effect in inhibiting aflatoxin formation in A. flavus through down-regulating aflatoxin pathway gene expression as demonstrated by gene chip analysis. Aflatoxin accumulation in potato dextrose broth liquid medium and liquid minimal medium was almost totally (more than 98 %) inhibited by co-cultivation with B. megaterium. Growth was also reduced. Using expression studies, we identified the fungal genes down-regulated by co-cultivation with B. megaterium across the entire fungal genome and specifically within the aflatoxin pathway gene cluster (aflF, aflT, aflS, aflJ, aflL, aflX). Modulating the expression of these genes could be used for controlling aflatoxin contamination in crops such as corn, cotton, and peanut. Importantly, the expression of the regulatory gene aflS was significantly down-regulated during co-cultivation. We present a model showing a hypothesis of the regulatory mechanism of aflatoxin production suppression by AflS and AflR through B. megaterium co-cultivation.

  17. Collision-induced dissociation of aflatoxins.

    PubMed

    Tóth, Katalin; Nagy, Lajos; Mándi, Attila; Kuki, Ákos; Mézes, Miklós; Zsuga, Miklós; Kéki, Sándor

    2013-02-28

    The aflatoxin mycotoxins are particularly hazardous to health when present in food. Therefore, from an analytical point of view, knowledge of their mass spectrometric properties is essential. The aim of the present study was to describe the collision-induced dissociation behavior of the four most common aflatoxins: B1, B2, G1 and G2. Protonated aflatoxins were produced using atmospheric pressure chemical ionization (APCI) mass spectrometry (MS) combined with high-performance liquid chromatography (HPLC). For the tandem mass spectrometry (MS/MS) experiments nitrogen was used as the collision gas and the collision energies were varied in the range of 9-44 eV (in the laboratory frame). The major APCI-MS/MS fragmentations of protonated aflatoxins occurred at 30 eV collision energy. The main fragmentation channels were found to be the losses of a series of carbon monoxide molecules and loss of a methyl radical, leading to the formation of radical-type product ions. In addition, if the aflatoxin molecule contained an ether- or lactone-oxygen atom linked to a saturated carbon atom, loss of a water molecule was observed from the [M + H](+) ion, especially in the case of aflatoxins G1 and G2. A relatively small modification in the structure of aflatoxins dramatically altered the fragmentation pathways and this was particularly true for aflatoxins B1 and B2. Due to the presence of a C = C double bond connected to the ether group in aflatoxin B1 no elimination of water was observed but, instead, formation of radical-type product ions occurred. Fragmentation of protonated aflatoxin B1 yielded the most abundant radical-type cations. Copyright © 2013 John Wiley & Sons, Ltd.

  18. Attempts to reduce exposure to fungi, β-glucan, bacteria, endotoxin and dust in vegetable greenhouses and a packaging unit.

    PubMed

    Madsen, Anne Mette; Tendal, Kira; Frederiksen, Margit W

    2014-01-15

    Indoor handling of large amounts of plant materials occurs in different occupational settings including greenhouses and causes exposure to bioaerosols. The bioaerosol components fungi, β-glucan, bacteria and endotoxin are involved in different airway symptoms and health effects can be dose-dependent. Therefore, there is a persistent need to reduce exposure. The aims of this study were to identify tasks causing exposure and to evaluate preventive measures aimed at reducing exposure of greenhouse workers to bioaerosols, and to study factors affecting the exposure. We have focused on different exposure scenarios; one with high short-term exposure found during clearing of old cucumber plants; the other with long-term, mid-level exposure found during tomato picking, leaf nipping, stringing up tomato plants, and packaging of cucumbers. Clearing of non-dried cucumber plants compared with clearing of dried cucumber plants significantly reduced the exposure to dust, endotoxin, bacteria, fungal spores and β-glucan. More endotoxin and fungi are emitted and more of the emitted particles were of respirable size if the leaves were dried. Along the cucumber packaging line, exposure levels were highly specific to each personal subtask. The subtask 'unloading of cucumbers' was the source of exposure making task ventilation or shielding of the process a possibility. Elimination of leaf debris on the floor reduced the exposure to fungi significantly. However, leaf debris on the floor did not contribute significantly to the exposure to dust, endotoxin and bacteria. Furthermore, to eliminate leaf debris, it had to be cleared away and this was associated with a higher exposure to dust and endotoxin. The age of the plants affected the exposure level to bioaerosols with higher exposures from old plants. In conclusion, different tasks and subtasks cause very different exposure levels. It is possible to reduce exposure by identifying subtasks causing the exposure and by modifying work

  19. Aflatoxin B1 contamination in maize in Europe increases due to climate change

    NASA Astrophysics Data System (ADS)

    Battilani, P.; Toscano, P.; van der Fels-Klerx, H. J.; Moretti, A.; Camardo Leggieri, M.; Brera, C.; Rortais, A.; Goumperis, T.; Robinson, T.

    2016-04-01

    Climate change has been reported as a driver for emerging food and feed safety issues worldwide and its expected impact on the presence of mycotoxins in food and feed is of great concern. Aflatoxins have the highest acute and chronic toxicity of all mycotoxins; hence, the maximal concentration in agricultural food and feed products and their commodities is regulated worldwide. The possible change in patterns of aflatoxin occurrence in crops due to climate change is a matter of concern that may require anticipatory actions. The aim of this study was to predict aflatoxin contamination in maize and wheat crops, within the next 100 years, under a +2 °C and +5 °C climate change scenario, applying a modelling approach. Europe was virtually covered by a net, 50 × 50 km grids, identifying 2254 meshes with a central point each. Climate data were generated for each point, linked to predictive models and predictions were run consequently. Aflatoxin B1 is predicted to become a food safety issue in maize in Europe, especially in the +2 °C scenario, the most probable scenario of climate change expected for the next years. These results represent a supporting tool to reinforce aflatoxin management and to prevent human and animal exposure.

  20. Aflatoxin B1 contamination in maize in Europe increases due to climate change.

    PubMed

    Battilani, P; Toscano, P; Van der Fels-Klerx, H J; Moretti, A; Camardo Leggieri, M; Brera, C; Rortais, A; Goumperis, T; Robinson, T

    2016-04-12

    Climate change has been reported as a driver for emerging food and feed safety issues worldwide and its expected impact on the presence of mycotoxins in food and feed is of great concern. Aflatoxins have the highest acute and chronic toxicity of all mycotoxins; hence, the maximal concentration in agricultural food and feed products and their commodities is regulated worldwide. The possible change in patterns of aflatoxin occurrence in crops due to climate change is a matter of concern that may require anticipatory actions. The aim of this study was to predict aflatoxin contamination in maize and wheat crops, within the next 100 years, under a +2 °C and +5 °C climate change scenario, applying a modelling approach. Europe was virtually covered by a net, 50 × 50 km grids, identifying 2254 meshes with a central point each. Climate data were generated for each point, linked to predictive models and predictions were run consequently. Aflatoxin B1 is predicted to become a food safety issue in maize in Europe, especially in the +2 °C scenario, the most probable scenario of climate change expected for the next years. These results represent a supporting tool to reinforce aflatoxin management and to prevent human and animal exposure.

  1. Aflatoxin B1 contamination in maize in Europe increases due to climate change

    PubMed Central

    Battilani, P.; Toscano, P.; Van der Fels-Klerx, H. J.; Moretti, A.; Camardo Leggieri, M.; Brera, C.; Rortais, A.; Goumperis, T.; Robinson, T.

    2016-01-01

    Climate change has been reported as a driver for emerging food and feed safety issues worldwide and its expected impact on the presence of mycotoxins in food and feed is of great concern. Aflatoxins have the highest acute and chronic toxicity of all mycotoxins; hence, the maximal concentration in agricultural food and feed products and their commodities is regulated worldwide. The possible change in patterns of aflatoxin occurrence in crops due to climate change is a matter of concern that may require anticipatory actions. The aim of this study was to predict aflatoxin contamination in maize and wheat crops, within the next 100 years, under a +2 °C and +5 °C climate change scenario, applying a modelling approach. Europe was virtually covered by a net, 50 × 50 km grids, identifying 2254 meshes with a central point each. Climate data were generated for each point, linked to predictive models and predictions were run consequently. Aflatoxin B1 is predicted to become a food safety issue in maize in Europe, especially in the +2 °C scenario, the most probable scenario of climate change expected for the next years. These results represent a supporting tool to reinforce aflatoxin management and to prevent human and animal exposure. PMID:27066906

  2. Comparison of nixtamalization and extrusion processes for a reduction in aflatoxin content.

    PubMed

    Elias-Orozco, R; Castellanos-Nava, A; Gaytán-Martínez, M; Figueroa-Cárdenas, J D; Loarca-Piña, G

    2002-09-01

    Traditional nixtamalization and an extrusion method for making the dough (masa) for corn tortillas that requires using lime and hydrogen peroxide were evaluated for the detoxification of aflatoxins. The traditional nixtamalization process reduced levels of aflatoxin B(1) (AFB(1)) by 94%, aflatoxin M(1) (AFM(1)) by 90% and aflatoxin B(1)-8,9-dihydrodiol (AFB(1)-dihydrodiol) by 93%. The extrusion process reduced levels of AFB(1) by 46%, AFM(1) by 20% and AFB(1)-dihydrodiol by 53%. Extrusion treatments with 0, 0.3 and 0.5% lime reduced AFB(1) levels by 46, 74 and 85%, respectively. The inactivation of AFB(1), AFM(1) and AFB(1)-dihydrodiol in the extrusion process using lime together with hydrogen peroxide showed higher elimination of AFB(1) than treatments with lime or hydrogen peroxide alone. The extrusion process with 0.3% lime and 1.5% hydrogen peroxide was the most effective process to detoxify aflatoxins in corn tortillas, but a high level of those reagents negatively affected the taste and aroma of the corn tortilla as compared with tortillas elaborated by the traditional nixtamalization process.

  3. Use of high-performance liquid chromatography to assess airborne mycotoxins. Aflatoxins and ochratoxin A.

    PubMed

    Tarín, A; Rosell, M G; Guardino, X

    2004-08-27

    An HPLC analytical method combining methanol-deionised water (80:20, v/v) extraction, methanol-acetonitrile (50:50, v/v) extraction and fluorescence detection was implanted to analyse ochratoxin A and aflatoxins B1, B2, G1 and G2 of air samples collected during the usual production process in a number of workplaces of a coffee factory to assess the occupational exposure of the engaged workers. The average levels of airborne ochratoxin A and aflatoxins were less than 1.2 and 0.4 ng/m3, respectively, using 50 L air samples. When 150 L air samples were used, levels lower than 0.04 ng/m3 ochratoxin A and 0.013 ng/m3 for aflatoxins B1, B2, G1 and G2, could be detected.

  4. A Complex Interaction Between Reduced Reelin Expression and Prenatal Organophosphate Exposure Alters Neuronal Cell Morphology.

    PubMed

    Mullen, Brian R; Ross, Brennan; Chou, Joan Wang; Khankan, Rana; Khialeeva, Elvira; Bui, Kimberly; Carpenter, Ellen M

    2016-06-01

    Genetic and environmental factors are both likely to contribute to neurodevelopmental disorders including schizophrenia, autism spectrum disorders, and major depressive disorders. Prior studies from our laboratory and others have demonstrated that the combinatorial effect of two factors-reduced expression of reelin protein and prenatal exposure to the organophosphate pesticide chlorpyrifos oxon-gives rise to acute biochemical effects and to morphological and behavioral phenotypes in adolescent and young adult mice. In the current study, we examine the consequences of these factors on reelin protein expression and neuronal cell morphology in adult mice. While the cell populations that express reelin in the adult brain appear unchanged in location and distribution, the levels of full length and cleaved reelin protein show persistent reductions following prenatal exposure to chlorpyrifos oxon. Cell positioning and organization in the hippocampus and cerebellum are largely normal in animals with either reduced reelin expression or prenatal exposure to chlorpyrifos oxon, but cellular complexity and dendritic spine organization is altered, with a skewed distribution of immature dendritic spines in adult animals. Paradoxically, combinatorial exposure to both factors appears to generate a rescue of the dendritic spine phenotypes, similar to the mitigation of behavioral and morphological changes observed in our prior study. Together, our observations support an interaction between reelin expression and chlorpyrifos oxon exposure that is not simply additive, suggesting a complex interplay between genetic and environmental factors in regulating brain morphology. © The Author(s) 2016.

  5. Embryonic arsenic exposure reduces the number of muscle fibers in killifish (Fundulus heteroclitus).

    PubMed

    D'Amico, Angela R; Gibson, Alec W; Bain, Lisa J

    2014-01-01

    Arsenic is a contaminant of drinking water and has been correlated with adverse developmental outcomes such as low birth weight, reduced weight gain, and altered locomotor activity. Previous research has shown that killifish (Fundulus heteroclitus) exposed to high arsenic levels during embryogenesis had smaller muscle fiber diameters. The current study was designed to determine whether changes in muscle fibers persisted, were exacerbated, or resolved over time. Killifish embryos were exposed to 0-5 ppm arsenite and, upon hatching, were transferred into either clean water or continued receiving the same exposure to arsenic for up to 16 weeks. Arsenic significantly decreased the weight of both embryonic-only exposed juveniles and continuously exposed juveniles between 4 and 16 weeks of development at concentrations as low as 0.8 ppm. Although arsenite exposure increased the percentage of small diameter fibers during the early weeks, fiber diameters returned to control levels in the embryonic-only exposed fish. However, muscle fiber density was still reduced to 85.7%, 80.3%, and 73.8% of control for the 0.8, 2, and 5 ppm embryonic-only exposure groups, respectively, even after 16 weeks of development. These results indicate that while continuous exposure to arsenic may alter the size of muscle fibers, embryonic-only exposure to arsenic has lasting effects on the number of muscle fibers formed.

  6. Personalized technologist dose audit feedback for reducing patient radiation exposure from CT.

    PubMed

    Miglioretti, Diana L; Zhang, Yue; Johnson, Eric; Lee, Choonsik; Morin, Richard L; Vanneman, Nicholas; Smith-Bindman, Rebecca

    2014-03-01

    The aim of this study was to determine whether providing radiologic technologists with audit feedback on doses from CT examinations they conduct and education on dose-reduction strategies reduces patients' radiation exposure. This prospective, controlled pilot study was conducted within an integrated health care system from November 2010 to October 2011. Ten technologists at 2 facilities received personalized dose audit reports and education on dose-reduction strategies; 9 technologists at a control facility received no intervention. Radiation exposure was measured by the dose-length product (DLP) from CT scans performed before (n = 1,630) and after (n = 1,499) the intervention and compared using quantile regression. Technologists were surveyed before and after the intervention. For abdominal CT, DLPs decreased by 3% to 12% at intervention facilities but not at the control facility. For brain CT, DLPs significantly decreased by 7% to 12% at one intervention facility; did not change at the second intervention facility, which had the lowest preintervention DLPs; and increased at the control facility. Technologists were more likely to report always thinking about radiation exposure and associated cancer risk and optimizing settings to reduce exposure after the intervention. Personalized audit feedback and education can change technologists' attitudes about, and awareness of, radiation and can lower patient radiation exposure from CT imaging. Copyright © 2014 American College of Radiology. All rights reserved.

  7. A Complex Interaction Between Reduced Reelin Expression and Prenatal Organophosphate Exposure Alters Neuronal Cell Morphology

    PubMed Central

    Mullen, Brian R.; Ross, Brennan; Chou, Joan Wang; Khankan, Rana; Khialeeva, Elvira; Bui, Kimberly

    2016-01-01

    Genetic and environmental factors are both likely to contribute to neurodevelopmental disorders including schizophrenia, autism spectrum disorders, and major depressive disorders. Prior studies from our laboratory and others have demonstrated that the combinatorial effect of two factors—reduced expression of reelin protein and prenatal exposure to the organophosphate pesticide chlorpyrifos oxon—gives rise to acute biochemical effects and to morphological and behavioral phenotypes in adolescent and young adult mice. In the current study, we examine the consequences of these factors on reelin protein expression and neuronal cell morphology in adult mice. While the cell populations that express reelin in the adult brain appear unchanged in location and distribution, the levels of full length and cleaved reelin protein show persistent reductions following prenatal exposure to chlorpyrifos oxon. Cell positioning and organization in the hippocampus and cerebellum are largely normal in animals with either reduced reelin expression or prenatal exposure to chlorpyrifos oxon, but cellular complexity and dendritic spine organization is altered, with a skewed distribution of immature dendritic spines in adult animals. Paradoxically, combinatorial exposure to both factors appears to generate a rescue of the dendritic spine phenotypes, similar to the mitigation of behavioral and morphological changes observed in our prior study. Together, our observations support an interaction between reelin expression and chlorpyrifos oxon exposure that is not simply additive, suggesting a complex interplay between genetic and environmental factors in regulating brain morphology. PMID:27364165

  8. Prolonged exposure to acetaminophen reduces testosterone production by the human fetal testis in a xenograft model

    PubMed Central

    Anderson, Richard A.; Johnston, Zoe C.; Chetty, Tarini; Smith, Lee B.; Mckinnell, Chris; Dean, Afshan; Homer, Natalie Z.; Jorgensen, Anne; Camacho-Moll, Maria-Elena; Sharpe, Richard M.; Mitchell, Rod T.

    2016-01-01

    Most common male reproductive disorders are linked to lower testosterone exposure in fetal life, although the factors responsible for suppressing fetal testosterone remain largely unknown. Protracted use of acetaminophen during pregnancy is associated with increased risk of cryptorchidism in sons, but effects on fetal testosterone production have not been demonstrated. We used a validated xenograft model to expose human fetal testes to clinically relevant doses and regimens of acetaminophen. Exposure to a therapeutic dose of acetaminophen for 7 days significantly reduced plasma testosterone (45% reduction; p=0.025) and seminal vesicle weight (a biomarker of androgen exposure; 18% reduction; p=0.005) in castrate host mice bearing human fetal testis xenografts, whereas acetaminophen exposure for just 1 day did not alter either parameter. Plasma acetaminophen concentrations (at 1 hour after the final dose) in exposed host mice were substantially below those reported in humans after a therapeutic oral dose. Subsequent in utero exposure studies in rats indicated that the acetaminophen-induced reduction in testosterone likely results from reduced expression of key steroidogenic enzymes (Cyp11a1, Cyp17a1). Our results suggest that protracted use of acetaminophen (1 week) may suppress fetal testosterone production, which could have adverse consequences. Further studies are required to establish the dose-response and treatment-duration relationships to delineate the maximum dose and treatment period without this adverse effect. PMID:25995226

  9. Manipulations of exposure-based therapy to reduce return of fear: a replication.

    PubMed

    Lang, A J; Craske, M G

    2000-01-01

    Using exposure-based treatment for fear of heights, we tested two different manipulations, namely administering blocks of exposure trials on an expanding spaced schedule and varying the nature of the exposure, both of which have been shown to reduce return of fear [Rowe, M. K., & Craske, M. G. (1998a). Effects of an expanding-spaced versus massed exposure schedule on fear reduction and return of fear. Behaviour Research and Therapy, 36, 701-718; Rowe, M. K., & Craske, M. G. (1998b). Effects of varied-stimulus exposure training on fear reduction and return of fear. Behaviour Research and Therapy, 36, 719-734.]. The samples for these two studies included 23 and 34 undergraduates, respectively. Fear was assessed before, immediately after and one month after treatment using self-report and physiological measures. Study hypotheses were not strongly supported, but the manipulations did lead to different responses during treatment. The data suggest that physiological habituation is not necessary for fear reduction. Expanding spaced treatment may have increased generalization, and those in the constant and varied conditions responded to different aspects of the exposure. Reasons for the failure to replicate previous research and ideas for future research are discussed.

  10. Reducing Health Risks from Indoor Exposures in Rapidly Developing Urban China

    PubMed Central

    Zhang, Yinping; Mo, Jinhan

    2013-01-01

    Background: Over the past two decades there has been a large migration of China’s population from rural to urban regions. At the same time, residences in cities have changed in character from single-story or low-rise buildings to high-rise structures constructed and furnished with many synthetic materials. As a consequence, indoor exposures (to pollutants with outdoor and indoor sources) have changed significantly. Objectives: We briefly discuss the inferred impact that urbanization and modernization have had on indoor exposures and public health in China. We argue that growing adverse health costs associated with these changes are not inevitable, and we present steps that could be taken to reduce indoor exposures to harmful pollutants. Discussion: As documented by China’s Ministry of Health, there have been significant increases in morbidity and mortality among urban residents over the past 20 years. Evidence suggests that the population’s exposure to air pollutants has contributed to increases in lung cancer, cardiovascular disease, pulmonary disease, and birth defects. Whether a pollutant has an outdoor or an indoor source, most exposure to the pollutant occurs indoors. Going forward, indoor exposures can be reduced by limiting the ingress of outdoor pollutants (while providing adequate ventilation with clean air), minimizing indoor sources of pollutants, updating government policies related to indoor pollution, and addressing indoor air quality during a building’s initial design. Conclusions: Taking the suggested steps could lead to significant reductions in morbidity and mortality, greatly reducing the societal costs associated with pollutant derived ill health. PMID:23665813

  11. Reducing radiation dose in emergency computed tomography with automatic exposure control techniques.

    PubMed

    Kalra, Mannudeep K; Rizzo, Stefania M R; Novelline, Robert A

    2005-07-01

    Computed tomography (CT) scanning is being increasingly used for evaluation of trauma, which most commonly involves younger individuals. As younger patients are at higher risk for radiation-induced cancer compared to older patients, radiation dose reduction is an important issue in emergency CT scanning. With automatic exposure control techniques, users select a desired image quality and the system adapts tube current to obtain the desired image quality with greater radiation dose efficiency. These techniques can help in reducing radiation dose by 10-60% in most instances. This review article presents a comprehensive description of fundamentals, clinical applications and radiation dose benefits of automatic exposure control in emergency CT scanning.

  12. Simultaneously reducing CO2 and particulate exposures via fractional recirculation of vehicle cabin air.

    PubMed

    Jung, Heejung S; Grady, Michael L; Victoroff, Tristan; Miller, Arthur L

    2017-07-01

    Prior studies demonstrate that air recirculation can reduce exposure to nanoparticles in vehicle cabins. However when people occupy confined spaces, air recirculation can lead to carbon dioxide (CO2) accumulation which can potentially lead to deleterious effects on cognitive function. This study proposes a fractional air recirculation system for reducing nanoparticle concentration while simultaneously suppressing CO2 levels in the cabin. Several recirculation scenarios were tested using a custom-programmed HVAC (heat, ventilation, air conditioning) unit that varied the recirculation door angle in the test vehicle. Operating the recirculation system with a standard cabin filter reduced particle concentrations to 1000 particles/cm(3), although CO2 levels rose to 3000 ppm. When as little as 25% fresh air was introduced (75% recirculation), CO2 levels dropped to 1000 ppm, while particle concentrations remained below 5000 particles/cm(3). We found that nanoparticles were removed selectively during recirculation and demonstrated the trade-off between cabin CO2 concentration and cabin particle concentration using fractional air recirculation. Data showed significant increases in CO2 levels during 100% recirculation. For various fan speeds, recirculation fractions of 50-75% maintained lower CO2 levels in the cabin, while still reducing particulate levels. We recommend fractional recirculation as a simple method to reduce occupants' exposures to particulate matter and CO2 in vehicles. A design with several fractional recirculation settings could allow air exchange adequate for reducing both particulate and CO2 exposures. Developing this technology could lead to reductions in airborne nanoparticle exposure, while also mitigating safety risks from CO2 accumulation.

  13. Simultaneously reducing CO2 and particulate exposures via fractional recirculation of vehicle cabin air

    NASA Astrophysics Data System (ADS)

    Jung, Heejung S.; Grady, Michael L.; Victoroff, Tristan; Miller, Arthur L.

    2017-07-01

    Prior studies demonstrate that air recirculation can reduce exposure to nanoparticles in vehicle cabins. However when people occupy confined spaces, air recirculation can lead to carbon dioxide (CO2) accumulation which can potentially lead to deleterious effects on cognitive function. This study proposes a fractional air recirculation system for reducing nanoparticle concentration while simultaneously suppressing CO2 levels in the cabin. Several recirculation scenarios were tested using a custom-programmed HVAC (heat, ventilation, air conditioning) unit that varied the recirculation door angle in the test vehicle. Operating the recirculation system with a standard cabin filter reduced particle concentrations to 1000 particles/cm3, although CO2 levels rose to 3000 ppm. When as little as 25% fresh air was introduced (75% recirculation), CO2 levels dropped to 1000 ppm, while particle concentrations remained below 5000 particles/cm3. We found that nanoparticles were removed selectively during recirculation and demonstrated the trade-off between cabin CO2 concentration and cabin particle concentration using fractional air recirculation. Data showed significant increases in CO2 levels during 100% recirculation. For various fan speeds, recirculation fractions of 50-75% maintained lower CO2 levels in the cabin, while still reducing particulate levels. We recommend fractional recirculation as a simple method to reduce occupants' exposures to particulate matter and CO2 in vehicles. A design with several fractional recirculation settings could allow air exchange adequate for reducing both particulate and CO2 exposures. Developing this technology could lead to reductions in airborne nanoparticle exposure, while also mitigating safety risks from CO2 accumulation.

  14. Simultaneously reducing CO2 and particulate exposures via fractional recirculation of vehicle cabin air

    PubMed Central

    Jung, Heejung S.; Grady, Michael L.; Victoroff, Tristan; Miller, Arthur L.

    2017-01-01

    Prior studies demonstrate that air recirculation can reduce exposure to nanoparticles in vehicle cabins. However when people occupy confined spaces, air recirculation can lead to carbon dioxide (CO2) accumulation which can potentially lead to deleterious effects on cognitive function. This study proposes a fractional air recirculation system for reducing nanoparticle concentration while simultaneously suppressing CO2 levels in the cabin. Several recirculation scenarios were tested using a custom-programmed HVAC (heat, ventilation, air conditioning) unit that varied the recirculation door angle in the test vehicle. Operating the recirculation system with a standard cabin filter reduced particle concentrations to 1000 particles/cm3, although CO2 levels rose to 3000 ppm. When as little as 25% fresh air was introduced (75% recirculation), CO2 levels dropped to 1000 ppm, while particle concentrations remained below 5000 particles/cm3. We found that nanoparticles were removed selectively during recirculation and demonstrated the trade-off between cabin CO2 concentration and cabin particle concentration using fractional air recirculation. Data showed significant increases in CO2 levels during 100% recirculation. For various fan speeds, recirculation fractions of 50–75% maintained lower CO2 levels in the cabin, while still reducing particulate levels. We recommend fractional recirculation as a simple method to reduce occupants’ exposures to particulate matter and CO2 in vehicles. A design with several fractional recirculation settings could allow air exchange adequate for reducing both particulate and CO2 exposures. Developing this technology could lead to reductions in airborne nanoparticle exposure, while also mitigating safety risks from CO2 accumulation. PMID:28781568

  15. Cinnamaldehyde inhibits fungal growth and aflatoxin B1 biosynthesis by modulating the oxidative stress response of Aspergillus flavus.

    PubMed

    Sun, Qi; Shang, Bo; Wang, Ling; Lu, Zhisong; Liu, Yang

    2016-02-01

    Cinnamaldehyde (CIN) is a promising natural preservative and generally recognized as safe for commodities as well as consumers. In this work, the antifungal effects of CIN on Aspergillus flavus were evaluated both in solid and in liquid culture conditions. Our results indicated that CIN effectively inhibited radial growth, spore production, mycelium formation, and aflatoxin B1 biosynthesis by A. flavus in a dose-dependent manner. At the concentration of 104 mg L(-1), CIN exposure was able to completely inhibit fungal growth as well as aflatoxin B1 production. Furthermore, the inhibitory activities of CIN were closely connected with the treatment period and the tested fungal species. Compared with the control strains, CIN dose dependently changed the morphology and ultrastructure of mycelium in different degree. Especially, the reduction of hydrogen peroxide was considered to follow the destruction of mitochondrial. Meanwhile, CIN significantly cut the levels of lipid peroxidation and reduced glutathione. The activity of total superoxide dismutase was significantly inhibited after CIN treatment at the end of incubation, whereas the activities of catalase and glutathione peroxidase were opposite. These results indicated that the inhibitory effect of CIN could attribute to oxidative stress alleviation possibly induced by modifications of cellular structure as well as redox status.

  16. Reduced exposure to air pollution on the boardwalk in Dublin, Ireland. Measurement and prediction.

    PubMed

    McNabola, A; Broderick, B M; Gill, L W

    2008-01-01

    This paper outlines an air pollution study carried out on Dublin city's recently completed boardwalk along the side of and overhanging the River Liffey. Air quality samples were taken along the length of the boardwalk to investigate whether pedestrians using the boardwalk would have a lower air pollution exposure than those using the adjoining footpath along the road. The results of the study show significant reductions in pedestrian exposure to both traffic derived particulates and hydrocarbons along the boardwalk as opposed to the footpath. Computational fluid dynamics was also used to model the outcome of these field measurements and shows the importance of the boundary wall between the footpath and boardwalk in reducing air pollution exposure for the pedestrian, the results of which are also presented herein.

  17. Prospective systematic intervention to reduce patient exposure to radiation during pediatric ureteroscopy.

    PubMed

    Kokorowski, Paul J; Chow, Jeanne S; Strauss, Keith J; Pennison, Melanie; Tan, William; Cilento, Bartley; Nelson, Caleb P

    2013-10-01

    After prospective measurement of radiation exposure during pediatric ureteroscopy for urolithiasis, we identified targets for intervention. We sought to systematically reduce radiation exposure during pediatric ureteroscopy. We designed and implemented a pre-fluoroscopy quality checklist for patients undergoing ureteroscopy at our institution as part of a quality improvement initiative. Preoperative patient characteristics, operative factors, fluoroscopy settings and radiation exposure were recorded. Primary outcomes were the entrance skin dose in mGy and midline dose in mGy before and after checklist implementation. We directly observed 32 consecutive ureteroscopy procedures using the safety checklist, of which 27 were done in pediatric patients who met study inclusion criteria. Outcomes were compared to those in 37 patients from the pre-checklist phase. Pre-checklist and postchecklist groups were similar in patient age, total operative time or patient thickness. The mean entrance skin dose and midline dose were decreased by 88% and 87%, respectively (p <0.01). Significant improvements were noted among the major radiation dose determinants, total fluoroscopy time (reduced by 67%), dose rate setting (appropriately reduced dose setting in 93% vs 51%) and excess skin-to-intensifier distance (reduced by 78%, each p <0.01). After systematic evaluation of our practices and implementation of a fluoroscopy quality checklist, there were dramatic decreases in radiation doses to children during ureteroscopy. Copyright © 2013 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  18. Occurrence of Aflatoxins and Aflatoxin-Producing Strains of Aspergillus spp. in Soybeans 1

    PubMed Central

    Bean, George A.; Schillinger, John A.; Klarman, William L.

    1972-01-01

    Above average rainfall in Maryland during August, September, and October 1971 resulted in heavy mold growth in soybeans while still in the field. Of 28 samples of soybean seed, aflatoxins were found in 14, 2 of which had been used in poultry feed. Aflatoxins were identified by thin-layer chromatography, spectrophotometry, and chicken embryo bioassay. Aspergillus spp. were isolated from 11 samples, and 5 of these isolates produced aflatoxins when grown in liquid culture. PMID:4673021

  19. Reduced nicotine cigarettes: smoking behavior and biomarkers of exposure among smokers not intending to quit.

    PubMed

    Hammond, David; O'Connor, Richard J

    2014-10-01

    The U.S. FDA has the authority to limit the nicotine content of cigarettes; however, there are concerns that reduced nicotine cigarettes will be smoked more intensely and, therefore, will increase exposure to toxic chemicals in smoke. This study examined changes in consumer behavior and exposure in response to cigarettes with substantially reduced nicotine content. Seventy-two adult smokers completed an unblinded trial of reduced nicotine cigarettes. Participants completed a 7-day baseline period during which they smoked their usual cigarette brand, followed by consecutive 7-day periods smoking cigarettes with progressively lower nicotine levels (0.6, 0.3, and 0.05 mg emission Quest cigarettes). Nicotine dependence and withdrawal, smoking behavior, and biomarkers of exposure were assessed for each 7-day period. Significant reductions in nicotine intake were observed between usual brand smoking (∼1.2 mg nicotine) and the 0.3 and 0.05 mg nicotine emission cigarettes, but not the 0.6 mg cigarette. The findings provide little evidence of compensatory smoking of Quest cigarettes, with no increases in exhaled breath carbon monoxide levels, smoking intensity, or levels of 1-hydroxypyrene across study periods. No significant differences were observed for smoking urges or measures of nicotine dependence. The study adds to the evidence that cigarettes with markedly reduced nicotine content are not associated with increased smoking intensity or exposure to smoke toxicants. The findings add to the evidence base on reduced nicotine content cigarettes and have the potential to inform FDA policy on nicotine levels. ©2014 American Association for Cancer Research.

  20. QuickTox™ Kit for QuickScan Aflatoxin FREE.

    PubMed

    Polakowski, Sergiusz; Roberts, Russell W; Tanguay, Keith; Bailey, Cheryl; Davis, Alan H; Gow, Brendan

    2015-01-01

    The QuickTox Kit for QuickScan Aflatoxin FREE uses competitive lateral flow technology and a reader based system for quantitative determination of total aflatoxins in varied matrixes. Aqueous based extraction protocols are used for corn and wheat, reducing use of solvents. Fifty percent ethanol (Reagent Alcohol) extraction is used for oats, sorghum, and barley. Eighty percent ethanol (Reagent Alcohol) extraction is used for whole peanut, peanut seed, and peanut hull samples. Matrix specific assay procedures and calibration curves are used to enable analyses across multiple sample types. The performance of this assay was examined using naturally contaminated aflatoxin corn samples and spiked samples of barley, oats, sorghum, wheat, whole peanut, peanut seed, and peanut hull samples. All data were judged against previously established acceptance criteria. Performance was evaluated in linearity, selectivity, matrix, lot consistency, and robustness experiments in the sponsor's laboratory. Results produced in all studies except robustness were within acceptable ranges. Out of range robustness study results reflected simultaneous deviation in sample volume and assay development time compared to the standard assay procedures. Aflatoxin B1, B2, and G1 were detected with approximately equal sensitivity; sensitivity for G2 was 64% that of B1. The presence of other common mycotoxins did not interfere with the assay. Matrix studies in an independent laboratory examined corn and barley to challenge both aqueous and ethanol based extraction procedures. All data points in these studies fell within the ranges defined in the acceptance criteria. The assay exhibited a linear dose response over the range tested, 0-100 ppb, with R(2) values exceeding 0.93 and RSDr values for results ranging from 2.27 to 23.84%.

  1. Phenylpyrrole-resistance and aflatoxin production in Aspergillus parasiticus Speare.

    PubMed

    Markoglou, Anastasios N; Doukas, Eleftherios G; Ziogas, Basil N

    2008-10-31

    Mutants of Aspergillus parasiticus highly resistant to phenylpyrroles were isolated at a high mutation frequency, after UV-mutagenesis and selection on media containing fludioxonil. Studies on the effect of mutation(s) on the aflatoxin production resulted in the identification of two fludioxonil-resistant phenotypes: aflatoxigenic (FLD(afl)(+)) and non-aflatoxigenic (FLD(afl)(-)) mutant strains. Most of the FLD(afl)(+) mutant strains produced the aflatoxin B(1) at similar or even higher (up to 2.5-fold) concentrations than the wild-type parent strain on yeast extract sucrose medium. Interestingly, in most of these mutant strains the aflatoxigenic ability significantly increased (up to 4-fold) when the mutants were grown on fungicide-amended medium. However, a significant reduction in the aflatoxin production was observed in wheat grains by all FLD(afl)(+) mutant strains. Tests on the response of mutant strains to high osmotic pressure showed that most fludioxonil-resistant mutants were more sensitive to high osmolarity than the wild-type parent strain. Study of other fitness determining parameters showed that the mutation(s) for resistance to phenylpyrroles may or may not affect the mycelial growth rate, sporulation and conidial germination. However, in a number of aflatoxigenic-mutant strains these fitness parameters were unaffected or only slightly affected. Cross resistance studies with fungicides from different chemical groups showed that the mutation(s) for resistance to fludioxonil also highly reduced the sensitivity of mutant strains to the aromatic hydrocarbon and dicarboximide fungicides. No effect of phenylpyrroles resistance mutation(s) on fungitoxicity of triazoles, benzimidazoles, anilinopyrimidines, phenylpyridinamines, strobilurin-type fungicides and to the non site-specific inhibitors chlorothalonil and maneb was observed. The above mentioned data indicate, for the first time, the potential risk of increased aflatoxin contamination of agricultural

  2. Vision 20/20: Increased image resolution versus reduced radiation exposure

    SciTech Connect

    Ritman, Erik L.

    2008-06-15

    This is a review of methods, currently and potentially, available for significantly reducing x-ray exposure in medical x-ray imaging. It is stimulated by the radiation exposure implications of the growing use of helical scanning, multislice, x-ray computed tomography for screening, such as for coronary artery atherosclerosis and cancer of the colon and lungs. Screening requires high-throughput imaging with high spatial and contrast resolution to meet the need for high sensitivity and specificity of detection and classification of specific imaged features. To achieve this goal beyond what is currently available with x-ray imaging methods requires increased x-ray exposure, which increases the risk of tissue damage and ultimately cancer development. These consequences limit the utility of current x-ray imaging in screening of at-risk subjects who have not yet developed the clinical symptoms of disease. Current methods for reducing x-ray exposure in x-ray imaging, mostly achieved by increasing sensitivity and specificity of the x-ray detection process, may still have potential for an up-to-tenfold decrease. This could be sufficient for doubling the spatial resolution of x-ray CT while maintaining the current x-ray exposure levels. However, a spatial resolution four times what is currently available might be needed to adequately meet the needs for screening. Consequently, for the proposed need to increase spatial resolution, an additional order of magnitude of reduction of x-ray exposure would be needed just to keep the radiation exposure at current levels. This is conceivably achievable if refraction, rather than the currently used attenuation, of x rays is used to generate the images. Existing methods that have potential for imaging the consequences of refracted x ray in a clinical setting are (1) by imaging the edge enhancement that occurs at the interfaces between adjacent tissues of different refractive indices, or (2) by imaging the changes in interference

  3. Reducing prenatal phthalate exposure through maternal dietary changes: results from a pilot study

    PubMed Central

    Barrett, Emily S.; Velez, Marissa; Qiu, Xing; Chen, Shaw-Ree

    2016-01-01

    Objectives Diet is a major source of exposure to certain phthalates, a class of environmental chemicals associated with endocrine disruption in animal models and humans. Several studies have attempted to lower phthalate exposure through carefully designed dietary interventions, with inconsistent results. We conducted a dietary intervention pilot study with the objective to lower phthalate exposure in low-income pregnant women, a particularly vulnerable population. Methods Ten pregnant women consumed a provided diet consisting of mostly fresh, organic foods for three days. We collected urine samples before, during, and after the intervention and conducted semi-structured interviews to assess the feasibility and acceptability of the intervention. We used repeated measures ANOVA and paired t-tests to assess differences in urinary phthalate metabolite concentrations across the study, focusing on the metabolites of di-2-ethylhexyl phthalate (DEHP), a phthalate of particular interest, and their molar sum (∑DEHP). Results Phthalate metabolite concentrations did not change appreciably during the intervention period. We observed no significant difference in ∑DEHP metabolite concentrations across the three time periods (F=0.21; adjusted p-value=0.65), and no reduction during the intervention as compared to baseline (t=−1.07, adjusted p-value=0.51). Results of interviews indicated that participants were not motivated to make dietary changes to potentially reduce chemical exposures outside of the study. Conclusions Despite the small sample size, our results suggest that promoting dietary changes to lower phthalate exposure may not be an effective public health measure. Reducing the use of phthalates in food processing and packaging may be a better solution to lowering exposure on a population level. PMID:25652062

  4. Trichloroethylene exposure reduces liver injury in a mouse model of primary biliary cholangitis.

    PubMed

    Ray, Jessica L; Kopec, Anna K; Joshi, Nikita; Cline-Fedewa, Holly; Lash, Lawrence H; Williams, Kurt J; Leung, Patrick S; Gershwin, M Eric; Luyendyk, James P

    2017-01-23

    Trichloroethylene (TCE) is a persistent environmental contaminant proposed to contribute to autoimmune disease. Experimental studies in lupus-prone MRL(+/+) mice have suggested that TCE exposure can trigger autoimmune hepatitis. The vast majority of studies examining the connection between TCE and autoimmunity utilize this model, and the impact of TCE exposure in other established models of autoimmune liver disease is not known. We tested the hypothesis that TCE exposure exacerbates experimental hepatic autoimmunity in dominant negative transforming growth factor beta receptor type II (dnTGFBRII) mice, which develop serological and histological features resembling human primary biliary cholangitis. Female 8-week-old wild-type and dnTGFBRII mice were exposed to TCE (0.5 mg/ml) or vehicle (1% ethoxylated castor oil) in the drinking water for 12 or 22 weeks. Liver histopathology in 20- and 30-week-old wild-type mice was unremarkable irrespective of treatment. Mild portal inflammation was observed in vehicle-exposed 20-week-old dnTGFBRII mice and was not exacerbated by TCE exposure. Vehicle-exposed 30-week-old dnTGFBRII mice developed anti-mitochondrial antibodies, marked hepatic inflammation with necrosis, and hepatic accumulation of both B and T lymphocytes. To our surprise, TCE exposure dramatically reduced hepatic parenchymal inflammation and injury in 30-week-old dnTGFBRII mice, reflected by changes in hepatic proinflammatory gene expression, serum chemistry, and histopathology. Interestingly, TCE did not affect hepatic B cell accumulation or induction of the anti-inflammatory cytokine IL10. These data indicate that TCE exposure reduces autoimmune liver injury in female dnTGFBRII mice and suggests that the precise effect of environmental chemicals in autoimmunity depends on the experimental model.

  5. Reducing Prenatal Phthalate Exposure Through Maternal Dietary Changes: Results from a Pilot Study.

    PubMed

    Barrett, Emily S; Velez, Marissa; Qiu, Xing; Chen, Shaw-Ree

    2015-09-01

    Diet is a major source of exposure to certain phthalates, a class of environmental chemicals associated with endocrine disruption in animal models and humans. Several studies have attempted to lower phthalate exposure through carefully designed dietary interventions, with inconsistent results. We conducted a dietary intervention pilot study with the objective to lower phthalate exposure in low-income pregnant women, a particularly vulnerable population. Ten pregnant women consumed a provided diet consisting of mostly fresh, organic foods for 3 days. We collected urine samples before, during, and after the intervention and conducted semi-structured interviews to assess the feasibility and acceptability of the intervention. We used repeated measures ANOVA and paired t-tests to assess differences in urinary phthalate metabolite concentrations across the study, focusing on the metabolites of di-2-ethylhexyl phthalate (DEHP), a phthalate of particular interest, and their molar sum (∑DEHP). Phthalate metabolite concentrations did not change appreciably during the intervention period. We observed no significant difference in ∑DEHP metabolite concentrations across the three time periods (F = 0.21; adjusted p value = 0.65), and no reduction during the intervention as compared to baseline (t = -1.07, adjusted p value = 0.51). Results of interviews indicated that participants were not motivated to make dietary changes to potentially reduce chemical exposures outside of the study. Despite the small sample size, our results suggest that promoting dietary changes to lower phthalate exposure may not be an effective public health measure. Reducing the use of phthalates in food processing and packaging may be a better solution to lowering exposure on a population level.

  6. Enzymatic Formation of G-Group Aflatoxins and Biosynthetic Relationship between G- and B-Group Aflatoxins

    PubMed Central

    Yabe, Kimiko; Nakamura, Miki; Hamasaki, Takashi

    1999-01-01

    We detected biosynthetic activity for aflatoxins G1 and G2 in cell extracts of Aspergillus parasiticus NIAH-26. We found that in the presence of NADPH, aflatoxins G1 and G2 were produced from O-methylsterigmatocystin and dihydro-O-methylsterigmatocystin, respectively. No G-group aflatoxins were produced from aflatoxin B1, aflatoxin B2, 5-methoxysterigmatocystin, dimethoxysterigmatocystin, or sterigmatin, confirming that B-group aflatoxins are not the precursors of G-group aflatoxins and that G- and B-group aflatoxins are independently produced from the same substrates (O-methylsterigmatocystin and dihydro-O-methylsterigmatocystin). In competition experiments in which the cell-free system was used, formation of aflatoxin G2 from dihydro-O-methylsterigmatocystin was suppressed when O-methylsterigmatocystin was added to the reaction mixture, whereas aflatoxin G1 was newly formed. This result indicates that the same enzymes can catalyze the formation of aflatoxins G1 and G2. Inhibition of G-group aflatoxin formation by methyrapone, SKF-525A, or imidazole indicated that a cytochrome P-450 monooxygenase may be involved in the formation of G-group aflatoxins. Both the microsome fraction and a cytosol protein with a native mass of 220 kDa were necessary for the formation of G-group aflatoxins. Due to instability of the microsome fraction, G-group aflatoxin formation was less stable than B-group aflatoxin formation. The ordA gene product, which may catalyze the formation of B-group aflatoxins, also may be required for G-group aflatoxin biosynthesis. We concluded that at least three reactions, catalyzed by the ordA gene product, an unstable microsome enzyme, and a 220-kDa cytosol protein, are involved in the enzymatic formation of G-group aflatoxins from either O-methylsterigmatocystin or dihydro-O-methylsterigmatocystin. PMID:10473388

  7. Effect of γ irradiation on fungal load and aflatoxins reduction in red chillies

    NASA Astrophysics Data System (ADS)

    Iqbal, Shahzad Zafar; Bhatti, Ijaz Ahmad; Asi, Muhammad Rafique; Zuber, Mohammad; Shahid, Muhammad; Parveen, Ishrat

    2013-01-01

    Chillies are a very important cash crop of Pakistan. The effects of gamma irradiation on microbial load, aflatoxin B1 (AFB1) and total aflatoxins have been studied in chillies samples, collected from different districts of Punjab, Pakistan. Aflatoxins were analyzed using HPLC equipped with a fluorescence detector. The results revealed that among the Aspergillus species isolated, those belonging to section parasiticus were predominant. Gamma radiations of doses 2, 4 and 6 kGy were employed on fungi and chilli samples. The results have demonstrated that the dose of 6 kGy reduced the fungal load by 5 logs. Furthermore, 6 kGy reduced the level of AFB1 and total AFs in ground and whole chillies by 1-2 logs (α < 0.05).

  8. Unexpected results in a randomized dietary trial to reduce phthalate and bisphenol A exposures.

    PubMed

    Sathyanarayana, Sheela; Alcedo, Garry; Saelens, Brian E; Zhou, Chuan; Dills, Russell L; Yu, Jianbo; Lanphear, Bruce

    2013-07-01

    Diet is a primary source of exposure for high-molecular-weight phthalates and bisphenol A (BPA), but little is known about the efficacy of various interventions to reduce exposures. We conducted a randomized trial with 10 families to test the efficacy of a 5-day complete dietary replacement (Arm 1; n=21) versus written recommendations to reduce phthalate and BPA exposures (Arm 2; n=19). We measured phthalate and BPA concentrations in urine samples at baseline, intervention, and post-intervention periods. We used Wilcoxon paired signed-rank tests to assess change in concentrations across time and multi-level mixed effects regression models to assess differences between Arms 1 and 2. Urinary di(2-ethylhexyl) phthalate (DEHP) metabolite concentrations increased unexpectedly from a median of 283.7 nmol/g at baseline to 7027.5 nmol/g during the intervention (P<0.0001) among Arm 1 participants, and no significant changes were observed for Arm 2 participants. We observed a statistically significant increase in total BPA concentration between baseline and intervention periods in Arm 1 but no significant changes in Arm 2. Arm 1 food ingredient testing for DEHP revealed concentrations of 21,400 ng/g in ground coriander and 673 ng/g in milk. Food contamination with DEHP led to unexpected increases in urinary phthalate concentrations in a trial intended to minimize exposure. In the absence of regulation to reduce phthalate and BPA concentrations in food production, it may be difficult to develop effective interventions that are feasible in the general population. An estimate of DEHP daily intake for children in the dietary replacement Arm was above the US Environmental Protection Agency oral reference dose and the European Food Safety Authority's tolerable daily intake, suggesting that food contamination can be a major source of DEHP exposure.

  9. Nursing research in community-based approaches to reduce exposure to secondhand smoke.

    PubMed

    Hahn, Ellen J; Ashford, Kristin B; Okoli, Chizimuzo T C; Rayens, Mary Kay; Ridner, S Lee; York, Nancy L

    2009-01-01

    Secondhand smoke (SHS) is the third leading cause of preventable death in the United States and a major source of indoor air pollution, accounting for an estimated 53,000 deaths per year among nonsmokers. Secondhand smoke exposure varies by gender, race/ethnicity, and socioeconomic status. The most effective public health intervention to reduce SHS exposure is to implement and enforce smoke-free workplace policies that protect entire populations including all workers regardless of occupation, race/ethnicity, gender, age, and socioeconomic status. This chapter summarizes community and population-based nursing research to reduce SHS exposure. Most of the nursing research in this area has been policy outcome studies, documenting improvement in indoor air quality, worker's health, public opinion, and reduction in Emergency Department visits for asthma, acute myocardial infarction among women, and adult smoking prevalence. These findings suggest a differential health effect by strength of law. Further, smoke-free laws do not harm business or employee turnover, nor are revenues from charitable gaming affected. Additionally, smoke-free laws may eventually have a positive effect on cessation among adults. There is emerging nursing science exploring the link between SHS exposure to nicotine and tobacco dependence, suggesting one reason that SHS reduction is a quit smoking strategy. Other nursing research studies address community readiness for smoke-free policy, and examine factors that build capacity for smoke-free policy. Emerging trends in the field include tobacco free health care and college campuses. A growing body of nursing research provides an excellent opportunity to conduct and participate in community and population-based research to reduce SHS exposure for both vulnerable populations and society at large.

  10. Intervention to Lower Household Wood Smoke Exposure in Guatemala Reduces ST-Segment Depression on Electrocardiograms

    PubMed Central

    Smith, Kirk R.; Stone, Peter; Díaz, Anaité; Arana, Byron; Schwartz, Joel

    2011-01-01

    Background: A large body of evidence suggests that fine particulate matter (PM) air pollution is a cause of cardiovascular disease, but little is known in particular about the cardiovascular effects of indoor air pollution from household use of solid fuels in developing countries. RESPIRE (Randomized Exposure Study of Pollution Indoors and Respiratory Effects) was a randomized trial of a chimney woodstove that reduces wood smoke exposure. Objectives: We tested the hypotheses that the stove intervention, compared with open fire use, would reduce ST-segment depression and increase heart rate variability (HRV). Methods: We used two complementary study designs: a) between-groups comparisons based on randomized stove assignment, and b) before-and-after comparisons within control subjects who used open fires during the trial and received chimney stoves after the trial. Electrocardiogram sessions that lasted 20 hr were repeated up to three times among 49 intervention and 70 control women 38–84 years of age, and 55 control subjects were also assessed after receiving stoves. HRV and ST-segment values were assessed for each 30-min period. ST-segment depression was defined as an average value below –1.00 mm. Personal fine PM [aerodynamic diameter ≤ 2.5 μm (PM2.5)] exposures were measured for 24 hr before each electrocardiogram. Results: PM2.5 exposure means were 266 and 102 μg/m3 during the trial period in the control and intervention groups, respectively. During the trial, the stove intervention was associated with an odds ratio of 0.26 (95% confidence interval, 0.08–0.90) for ST-segment depression. We found similar associations with the before-and-after comparison. The intervention was not significantly associated with HRV. Conclusions: The stove intervention was associated with reduced occurrence of nonspecific ST-segment depression, suggesting that household wood smoke exposures affect ventricular repolarization and potentially cardiovascular health. PMID

  11. Effectiveness of common shelter-in-place techniques in reducing ammonia exposure following accidental release.

    PubMed

    Tarkington, Brett; Harris, Angela J; Barton, Paul S; Chandler, Ben; Goad, Phillip T

    2009-04-01

    Shelter-in-place strategies such as remaining indoors; breathing through a damp cloth; sealing cracks in windows and doors using towels, duct tape, or plastic sheeting; and running a shower are often recommended by emergency response officials to protect against accidental or intentional release of hazardous airborne chemicals and biologicals. Similar recommendations have been made to and used by community members exposed to anhydrous ammonia after catastrophic release of ammonia gas due to a derailment or other accidents. Such incidents have resulted in fatalities and serious injury to exposed individuals; however, other individuals within the same area have escaped injury and, in many cases, sustained no injuries as a result of sheltering-in-place. Although there are some studies that have evaluated the effectiveness of remaining in the home or breathing through a damp cloth to reduce exposure to various agents, there have been no studies that directly address the efficacy of running the shower in reducing exposure to ammonia gas. The present study was designed to simulate sheltering-in-place inside a typical bathroom with the shower running. The effectiveness of breathing through a damp cloth was also evaluated using a CPR mannequin placed inside a chamber built to represent a typical household bathroom. Ammonia gas at 300 or 1000 ppm was added to the chamber until the concentration peaked and stabilized, then the shower was turned on and the ammonia gas concentration was continuously monitored. In the mannequin studies, using a damp cloth reduced exposure to ammonia gas by 2- to 18-fold. Turning on the shower was even more effective at reducing ammonia levels. After 27 min, the ammonia concentration in the chamber was reduced to 2% of the initial concentration, even though gas was being continuously added to the chamber. These results indicate that use of shelter-in-place strategies substantially reduces ammonia exposure and that by combining shelter

  12. Exposure to sucrose during periods of withdrawal does not reduce cocaine-seeking behavior in rats

    PubMed Central

    Nicolas, Céline; Lafay-Chebassier, Claire; Solinas, Marcello

    2016-01-01

    Concomitant access to drugs of abuse and alternative rewards such as sucrose has been shown to decrease addiction-related behaviors in animals. Here we investigated whether access to sucrose during abstinence in contexts that are temporally and physically distinct from drug-related contexts could reduce subsequent drug seeking. In addition, we investigated whether a history of cocaine self-administration would alter the rewarding effects of sucrose. Rats self-administered cocaine for ten sessions, while yoked-saline rats received only saline injections, and then we subjected them to a 30-day withdrawal period during which they had access to water and sucrose continuously or intermittently according to a schedule that induces binge-drinking behavior. At the end of the withdrawal period, rats were tested for cocaine seeking behavior during a single 6 h session. We found that exposure to cocaine increased sucrose consumption only when rats had intermittent access to sucrose, but exposure to sucrose did not alter drug seeking regardless of the schedule of access. These results suggest that exposure to cocaine cross-sensitizes to the rewarding effects of sucrose, but exposure to sucrose during abstinence, temporally and physically distinct from drug-related environments, does not to reduce drug seeking. PMID:26997496

  13. Exposure to sucrose during periods of withdrawal does not reduce cocaine-seeking behavior in rats.

    PubMed

    Nicolas, Céline; Lafay-Chebassier, Claire; Solinas, Marcello

    2016-03-21

    Concomitant access to drugs of abuse and alternative rewards such as sucrose has been shown to decrease addiction-related behaviors in animals. Here we investigated whether access to sucrose during abstinence in contexts that are temporally and physically distinct from drug-related contexts could reduce subsequent drug seeking. In addition, we investigated whether a history of cocaine self-administration would alter the rewarding effects of sucrose. Rats self-administered cocaine for ten sessions, while yoked-saline rats received only saline injections, and then we subjected them to a 30-day withdrawal period during which they had access to water and sucrose continuously or intermittently according to a schedule that induces binge-drinking behavior. At the end of the withdrawal period, rats were tested for cocaine seeking behavior during a single 6 h session. We found that exposure to cocaine increased sucrose consumption only when rats had intermittent access to sucrose, but exposure to sucrose did not alter drug seeking regardless of the schedule of access. These results suggest that exposure to cocaine cross-sensitizes to the rewarding effects of sucrose, but exposure to sucrose during abstinence, temporally and physically distinct from drug-related environments, does not to reduce drug seeking.

  14. Reduced tar, nicotine, and carbon monoxide exposure while smoking ultralow- but not low-yield cigarettes

    SciTech Connect

    Benowitz, N.L.; Jacob, P. III; Yu, L.; Talcott, R.; Hall, S.; Jones, R.T.

    1986-07-11

    An unresolved public health issue is whether some modern cigarettes are less hazardous than other and whether patients who cannot stop smoking should be advised to switch to lower-yield cigarettes. The authors studied tar (estimated by urine mutagenicity), nicotine, and carbon monoxide exposure in habitual smokers switched from their usual brand to high- (15 mg of tar), low- (5 mg of tar), or ultralow-yield (1 mg of tar) cigarettes. There were no differences in exposure comparing high- or low-yield cigarettes, but tar and nicotine exposures were reduced by 49% and 56%, respectively, and carbon monoxide exposure by 36% while smoking ultralow-yield cigarettes. Similarly, in 248 subjects smoking their self-selected brand, nicotine intake, estimated by blood concentrations of its metabolite continine, was 40% lower in those who smoked ultralow but no different in those smoking higher yields of cigarettes. The data indicate that ultralow-yield cigarettes do deliver substantial doses of tar, nicotine, and carbon monoxide, but that exposure are considerably less than for other cigarettes.

  15. Potential reduced exposure products (PREPs) for smokeless tobacco users: clinical evaluation methodology.

    PubMed

    Gray, Jennifer N; Breland, Alison B; Weaver, Michael; Eissenberg, Thomas

    2008-09-01

    Several potential reduced exposure products (PREPs) for smokeless tobacco (SLT) users are marketed in the United States, though their effects are largely unknown. These products include some that are low in tobacco-specific nitrosamines (TSNs), like Stonewall, a pressed tobacco tablet, and General snus, a moist snuff product produced in Sweden. Methodology assessing the toxicant exposure and effects of cigarette-like PREPs for smokers has been developed, and might be modified for use in evaluating PREPs for SLT users. This report describes two studies examining the toxicant exposure and effects of two PREPs for SLT users. Study 1 (n = 13) consisted of four 4.5-hr laboratory sessions where SLT products (own brand, Stonewall, General snus, and tobacco-free placebo) were used for four 30-min episodes and nicotine exposure and tobacco/nicotine abstinence symptoms were measured. Study 2 (n = 19) consisted of four 5-day ad libitum use periods when participants used own brand, Stonewall, General snus, or no SLT and urinary levels of metabolites of nicotine (cotinine) and the TSN 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNAL) and abstinence symptoms were measured. Compared with own brand, Stonewall was associated with lower levels of cotinine and NNAL, while General snus was associated with similar levels of cotinine and lower levels of NNAL. Abstinence symptoms generally did not differ across tobacco conditions. These results show that clinical laboratory methods can be used to evaluate the toxicant exposure and abstinence symptom suppression associated with PREPs for SLT users.

  16. Secondhand tobacco smoke exposure is associated with increased risk of failed implantation and reduced IVF success

    PubMed Central

    Benedict, Merle D.; Missmer, Stacey A.; Vahratian, Anjel; Berry, Katharine F.; Vitonis, Allison F.; Cramer, Daniel W.; Meeker, John D.

    2011-01-01

    BACKGROUND Infertility and early pregnancy loss are prevalent as is exposure to secondhand tobacco smoke (STS). Previous research has suggested a relationship between STS exposure and early pregnancy loss, but studies have been limited by small study sizes and/or imprecise methods for exposure estimation. IVF allows for the collection of follicular fluid (FF), the fluid surrounding the pre-ovulatory oocyte, which may be a more biologically relevant sample media than urine or serum in studies of early reproduction. METHODS In a retrospective analysis of a prospective cohort study, we measured cotinine in FF collected during 3270 IVF treatment cycles from 1909 non-smoking women between 1994 and 2003 to examine the relationship between STS exposure and implantation failure. RESULTS In adjusted models, we found a significant increase in the risk of implantation failure among women exposed to STS compared with those unexposed [odds ratio (OR) = 1.52; 95% confidence interval (CI) = 1.20–1.92; risk ratio (RR) = 1.17; 95% CI = 1.10–1.25]. We also found a significant decrease in the odds for a live birth among STS-exposed women (OR = 0.75; 95% CI = 0.57–0.99; RR = 0.81; 95% CI = 0.66–0.99). CONCLUSIONS Female STS exposure, estimated through the measurement of cotinine in FF, is associated with an increased risk of implantation failure and reduced odds of a live birth. PMID:21771769

  17. Counseling to reduce children's secondhand smoke exposure and help parents quit smoking: a controlled trial.

    PubMed

    Hovell, Melbourne F; Zakarian, Joy M; Matt, Georg E; Liles, Sandy; Jones, Jennifer A; Hofstetter, C Richard; Larson, Sarah N; Benowitz, Neal L

    2009-12-01

    We tested a combined intervention to reduce children's secondhand smoke exposure (SHSe) and help parents quit smoking. After baseline, mothers who exposed their children younger than 4 years to 10 or more cigarettes/week were randomized to the intervention (n = 76) or usual care control condition (n = 74). Outcomes were assessed at 3, 6, 12, and 18 months. Intervention families were offered 10 in-person at home and 4 telephone counseling sessions over 6 months, and additional pre- and postquit telephone sessions. Counseling procedures included behavioral contracting, self-monitoring, and problem solving. Parents' reports of their smoking and children's exposure showed moderate and significant correlations with children's urine cotinine levels and home air nicotine (r = .40-.78). Thirteen (17.1%) intervention group mothers and 4 (5.4%) controls reported that they quit smoking for 7 days prior to 1 or more study measurements, without biochemical contradiction (p = .024). Results of generalized estimating equations showed significantly greater decrease in reported SHSe and mothers' smoking in the counseled group compared with controls. Reported indoor smoking and children's urine cotinine decreased, yet group differences for changes were not significant. Nicotine contamination of the home and resulting thirdhand exposure may have contributed to the failure to obtain a differential decrease in cotinine concentration. Partial exposure to counseling due to dropouts and lack of full participation from all family members and measurement reactivity in both conditions may have constrained intervention effects. Secondhand smoke exposure counseling may have been less powerful when combined with smoking cessation.

  18. Acute Exposure to Crystalline Silica Reduces Macrophage Activation in Response to