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The Cochrane Database of Systematic... Apr 2020Aflatoxins are carcinogenic mycotoxins that contaminate many food crops. Maize and groundnuts are prone to aflatoxin contamination, and are the major sources of human... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Aflatoxins are carcinogenic mycotoxins that contaminate many food crops. Maize and groundnuts are prone to aflatoxin contamination, and are the major sources of human exposure to aflatoxins, due to their high intake as staple foods, particularly in low- and middle-income countries (LMICs). Observational studies suggest an association between dietary exposure to aflatoxins during pregnancy and early childhood and linear growth in infants and young children.
OBJECTIVES
To assess the effects on pre- and postnatal growth outcomes when agricultural and nutritional education interventions during the post-harvest period that aim to reduce aflatoxin exposure are compared to usual support or no intervention. We assessed this in infants, children, and pregnant and lactating women at the household or community level in LMICs.
SEARCH METHODS
In July and August 2019, we searched: CENTRAL, MEDLINE, Embase, CINAHL, Web of Science Core Collection, Africa-Wide, LILACS, CAB Abstracts, Agricola, and two trials registers. We also checked the bibliographies of the included studies and contacted relevant mycotoxin organisations and researchers for additional studies.
SELECTION CRITERIA
We included randomised controlled trials (RCTs) and cluster-RCTs of agricultural education and nutritional education interventions of any duration, at the household or community level, aimed at reducing aflatoxin intake by infants, children, and pregnant and lactating women, in LMICs during the post-harvest period, compared to no intervention or usual support. We excluded studies that followed participants for less than four weeks. We assessed prespecified prenatal (at birth) and postnatal growth outcomes (during infancy, childhood, and adolescence), with linear growth (as the primary outcome), infectious disease morbidity, and unintended consequences.
DATA COLLECTION AND ANALYSIS
Two authors independently assessed study eligibility using prespecified criteria, extracted data, and assessed risk of bias of included RCTs. We evaluated the certainty of the evidence using GRADE, and presented the main results in a 'Summary of findings' table.
MAIN RESULTS
We included three recent cluster-RCTs reporting the effects of agricultural education plus post-harvest technologies, compared to usual agricultural support or no intervention. The participants were pregnant women and their children, lactating women and their infants (< 6 months), women of childbearing age, and young children (< 59 months), from rural, subsistence maize-farming communities in Kenya, Zimbabwe, and Tanzania. Two trials randomised villages to the intervention and control groups, including a total of at least 979 mother-child pairs from 60 villages. The third trial randomised 420 households, including 189 mother-child pairs and 231 women of childbearing age. Duration of the intervention and follow-up ranged between five and nine months. Due to risk of attrition bias, the overall risk of bias was unclear in one trial, and high in the other two trials. None of the included studies addressed the effects of nutritional education on pre- and postnatal growth. One trial reported outcomes not prespecified in our review, and we were unable to obtain unpublished growth data from the second trial, even after contacting the authors. The third trial, in lactating women and their infants in Tanzania, reported on the infants' weight-for-age z-score (WAZ) after six months. This trial found that providing agricultural education aimed at changing farmers' post-harvest practices to reduce aflatoxin exposure, by using demonstrations (e.g. handsorting, de-hulling of maize, drying sheets, and insecticides), may improve WAZ in infants from these farmers' households, on average, by 0.57 (95% confidence interval (CI) 0.16 to 0.98; 1 study; 249 participants; very low-certainty evidence), compared to infants from households where the farmers received routine agricultural extension services. Another way of reporting the effect on WAZ is to compare the proportion of underweight infants (WAZ > 2 SD below the reference median value) per group. This trial found that the intervention may reduce the proportion of underweight infants in the intervention households by 6.7% (95% CI -12.6 to -1.4; 249 participants; very low-certainty evidence) compared to control households. No studies reported on unintended effects of agricultural and nutritional education.
AUTHORS' CONCLUSIONS
Evidence on the effects on child growth in LMICs of agricultural or nutritional education interventions that reduce aflatoxin exposure was very limited; no included study reported on linear growth. Very low-certainty evidence suggested that agricultural education aimed at changing farmers' post-harvest practices to reduce aflatoxin exposure by using demonstrations, may result in an increase in WAZ, when compared to usual or no education.
Topics: Adult; Aflatoxins; Agriculture; Breast Feeding; Child, Preschool; Developing Countries; Female; Food Contamination; Growth; Humans; Infant; Kenya; Pregnancy; Prenatal Exposure Delayed Effects; Randomized Controlled Trials as Topic; Tanzania; Thinness; Zimbabwe
PubMed: 32270495
DOI: 10.1002/14651858.CD013376.pub2 -
Toxins Feb 2020This manuscript reviews the state-of-the-art regarding human biological monitoring (HBM) of mycotoxins in plasma serum and blood samples. After a comprehensive and...
This manuscript reviews the state-of-the-art regarding human biological monitoring (HBM) of mycotoxins in plasma serum and blood samples. After a comprehensive and systematic literature review, with a focus on the last five years, several aspects were analyzed and summarized: a) the biomarkers analyzed and their encountered levels, b) the analytical methodologies developed and c) the relationship between biomarker levels and some illnesses. In the literature reviewed, aflatoxin B1-lysine (AFB1-lys) and ochratoxin A (OTA) in plasma and serum were the most widely studied mycotoxin biomarkers for HBM. Regarding analytical methodologies, a clear increase in the development of methods for the simultaneous determination of multiple mycotoxins has been observed. For this purpose, the use of liquid chromatography (LC) methodologies, especially when coupled with tandem mass spectrometry (MS/MS) or high resolution mass spectrometry (HRMS), has grown. A high percentage of the samples analyzed for OTA or aflatoxin B1 (mostly as AFB1-lys) in the reviewed papers were positive, demonstrating human exposure to mycotoxins. This review confirms the importance of mycotoxin human biomonitoring and highlights the important challenges that should be faced, such as the inclusion of other mycotoxins in HBM programs, the need to increase knowledge of mycotoxin metabolism and toxicokinetics, and the need for reference materials and new methodologies for treating samples. In addition, guidelines are required for analytical method validation, as well as equations to establish the relationship between human fluid levels and mycotoxin intake.
Topics: Biological Monitoring; Biomarkers; Humans; Mycotoxins
PubMed: 32121036
DOI: 10.3390/toxins12030147 -
Mycotoxin Research May 2020Mycotoxin exposure from food occurs globally but is more common in hot humid environments, especially in low-income settings, and might affect pregnancy outcomes. This...
Mycotoxin exposure from food occurs globally but is more common in hot humid environments, especially in low-income settings, and might affect pregnancy outcomes. This study aimed to synthesize the evidence from epidemiological studies on the relationship between maternal or fetal exposure to different mycotoxins and the occurrence of adverse pregnancy outcomes. Multiple databases were systematically searched up to December 2018 to identify studies that assessed the association between mycotoxin exposure in pregnant women or fetuses and at least one pregnancy outcome. Studies were appraised and results were synthesized using standard methods for conducting systematic reviews. This review identified and included 17 relevant studies. There is some evidence to suggest that exposure to various Aspergillus mycotoxins (e.g., aflatoxin) during pregnancy may impair intrauterine fetal growth and promote neonatal jaundice. Findings were inconclusive concerning the influence of aflatoxin exposure on perinatal death and preterm birth. Only two studies assessed effects of maternal exposure to Fusarium mycotoxins (e.g., fumonisin) on adverse pregnancy outcomes. These studies found that maternal fumonisin exposure may be associated with hypertensive emergencies in pregnancy and with neural tube defects. Studies using grain farming and weather conditions as a proxy measure for mycotoxin exposure found that such exposure was associated with an increased risk of preterm birth and late-term miscarriage. In conclusion, there is already some evidence to suggest that exposure to mycotoxins during pregnancy may have detrimental effects on pregnancy outcomes. However, given the limited number of studies, especially on effects of Fusarium mycotoxins, more studies are needed for a more comprehensive understanding of the effects of different mycotoxins on maternal and fetal health and to guide public health policies and interventions.
Topics: Aflatoxins; Dietary Supplements; Female; Fumonisins; Humans; Maternal Exposure; Mycotoxins; Pregnancy; Pregnancy Complications; Pregnancy Outcome; Premature Birth
PubMed: 31989413
DOI: 10.1007/s12550-019-00384-6 -
Current Problems in Pediatric and... May 2019The majority of childhood deaths occur in low-income countries, with vaccine-preventable infections contributing greatly. Of the many possible environmental factors that...
The majority of childhood deaths occur in low-income countries, with vaccine-preventable infections contributing greatly. Of the many possible environmental factors that could hamper a child's immune response, mycotoxins rank among the least studied in spite of the high exposure in vulnerable populations. Aflatoxin crosses the placenta, is secreted in breast milk and is consumed widely in weaning diets by children with developing organ systems. This review describes the effects of mycotoxin exposure on immunity in children that may contribute to sub-optimal vaccine effectiveness. We searched electronic databases and references of identified articles for relevant studies on the effects of mycotoxins on the immune system in children. Geographical location, publication year, study design, sample selection, sample size, mean age, route of exposure were extracted on a standard template. Quality was assessed using Joanna Briggs Institute tool for appraisal of systematic reviews for prevalence studies. Our analyses and reporting were conducted in accordance with the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. Out of 806 articles screened, 5 observational studies met criteria for inclusion for review. The definition of exposures to mycotoxins and outcomes varied across the studies. Exposure to mycotoxins was positively associated with low birth weight and concentration of antibodies to asexual malaria parasites and hepatitis B surface antigen, and negatively associated with death and sIgA, antibodies to pneumococcal antigen 23. Despite the far-reaching clinical and public health effects of mycotoxin exposure among children, studies on the effects of mycotoxin exposure on immunity in children were few, small and mostly of low quality. There is an urgent need for carefully designed prospective studies in this neglected field to inform policy interventions for child health in settings where exposure to mycotoxins is high.
Topics: Antibodies; Antigens; Child; Child Health; Child Mortality; Child, Preschool; Developing Countries; Diet; Female; Humans; Infant; Infant, Low Birth Weight; Infant, Newborn; Male; Maternal Exposure; Mycotoxins; Pregnancy
PubMed: 31126742
DOI: 10.1016/j.cppeds.2019.04.004 -
Journal of Food Protection May 2019This meta-analysis was designed to review the published reports regarding the concentration and/or prevalence of aflatoxin M (AFM) in human breast milk in Iran. The... (Meta-Analysis)
Meta-Analysis
This meta-analysis was designed to review the published reports regarding the concentration and/or prevalence of aflatoxin M (AFM) in human breast milk in Iran. The carcinogenic risk for Iranian infants consuming this milk was estimated with the hazard index. The PubMed and Scopus databases and the Scientific Information Database were screened for relevant studies between 1995 and 2017, and 11 of the 112 collected studies were included in the systematic review and meta-analysis. The mean (95% confidence interval) concentration of AFM was 5.85 ng/L (4.54 to 7.15 ng/L), which was lower than the European Union standard (25 ng/L). The mean prevalence of AFM in breast milk in Iran was 42% (11 to 77%). The estimated daily intakes for male and female infants were 0.02 to 5.57 ng/kg and 0.02 to 3.68 ng/kg of body weight per day, respectively. The rank order of estimated daily intake for both male and female infants according to age was 1 week > 1 month > 6 months > 12 months. The hazard index for all age groups of infants in all provinces in Iran was less than 1. Therefore, infants in Iran were not considered at carcinogenic risk from AFM in human breast milk.
Topics: Adult; Aflatoxin M1; Animals; Carcinogens; Eating; Female; Food Contamination; Humans; Infant; Iran; Male; Milk, Human; Prevalence; Risk Assessment
PubMed: 30995144
DOI: 10.4315/0362-028X.JFP-18-367 -
Food Chemistry Dec 2018The study aimed to perform a meta-analysis on the fate of ochratoxin A (OTA), zearalenone (ZEN), deoxynivalenol (DON) and total aflatoxin (TAF) during steps of bread and... (Meta-Analysis)
Meta-Analysis
Impact of unit operations during processing of cereal-based products on the levels of deoxynivalenol, total aflatoxin, ochratoxin A, and zearalenone: A systematic review and meta-analysis.
The study aimed to perform a meta-analysis on the fate of ochratoxin A (OTA), zearalenone (ZEN), deoxynivalenol (DON) and total aflatoxin (TAF) during steps of bread and pasta-based products processing. A total of twenty and eight articles (549 data) collected from 1983 through June 2017 were included. Some of the investigated processing such as milling and fermentation caused an increase in the concentration of DON and TAF; although they reduce the concentration of ZEN and OTA. Also, heat processing (cooking) decrease the DON, OTA, and TAF and increase the concentration of ZEN in bread. Cooking reduces the concentration of DON and ZEN in the biscuit. Cooking of pasta reduces the content of DON; however, it increases the concentration of TFA. The findings showed that the mycotoxins and their fate were influenced differently by the unit operations steps involved in the preparation of the different cereal-based products.
Topics: Aflatoxins; Edible Grain; Food Contamination; Mycotoxins; Ochratoxins; Trichothecenes; Zearalenone
PubMed: 30064804
DOI: 10.1016/j.foodchem.2018.06.072 -
Food and Chemical Toxicology : An... Aug 2018This study aimed to estimate the prevalence and concentration of total aflatoxin (TAF) ochratoxin A (OTA), zearalenone (ZEN) and deoxynivalenol (DON) in bread,... (Meta-Analysis)
Meta-Analysis Review
This study aimed to estimate the prevalence and concentration of total aflatoxin (TAF) ochratoxin A (OTA), zearalenone (ZEN) and deoxynivalenol (DON) in bread, cornflakes, breakfast cereals and pasta-based products through meta-analysis. The required databases including (PubMed and Scopus databases) were investigated to collect data on the concentration and prevalence of mentioned mycotoxins in cereal-based products. Among 2461 explored articles in identification step, 38 articles with 9627 samples were included in the conducted meta-analysis. The prevalence and concentration of studied mycotoxins varied with the cereal-based food studied. In this context, the overall rank order of mycotoxins prevalence in the cereal foods was OTA > DON > ZEN > TAF > 15-ADON > 3-ADON. Also, the overall rank order of mycotoxins based on concentration in the cereal foods investigated was DON > ZEN > 15-ADON > OTA > 3-ADON > TAF. The findings of this meta-analysis may be useful for the building of risk assessment models aiming to derive data for the development of specific actions to reduce the exposure to OTA, ZEN, TAF, and DON through the consumption of the cereal-based products.
Topics: Aflatoxins; Edible Grain; Food Contamination; Ochratoxins; Prevalence; Trichothecenes; Zearalenone
PubMed: 29935247
DOI: 10.1016/j.fct.2018.06.037 -
Environmental Research Oct 2017Environmental chemical exposures have been implicated in pediatric kidney disease. No appraisal of the available evidence has been conducted on this topic. (Review)
Review
BACKGROUND
Environmental chemical exposures have been implicated in pediatric kidney disease. No appraisal of the available evidence has been conducted on this topic.
METHODS
We performed a systematic review of the epidemiologic studies that assessed association of environmental exposures with measures of kidney function and disease in pediatric populations. The search period went through July 2016.
RESULTS
We found 50 studies that met the search criteria and were included in this systematic review. Environmental exposures reviewed herein included lead, cadmium, mercury, arsenic, fluoride, aflatoxin, melamine, environmental tobacco, bisphenol A, dental procedures, phthalates, ferfluorooctanoic acid, triclosan, and thallium/uranium. Most studies assessed environmental chemical exposure via biomarkers but four studies assessed exposure via proximity to emission source. There was mixed evidence of association between metal exposures, and other non-metal environmental exposures and pediatric kidney disease and other kidney disease biomarkers. The evaluation of causality is hampered by the small numbers of studies for each type of environmental exposure, as well as lack of study quality and limited prospective evidence.
CONCLUSION
There is a need for well-designed epidemiologic studies of environmental chemical exposures and kidney disease outcomes.
Topics: Environmental Exposure; Environmental Pollutants; Humans; Kidney; Kidney Diseases; Kidney Function Tests
PubMed: 28727988
DOI: 10.1016/j.envres.2017.06.029 -
Mutation Research. Reviews in Mutation... 2016Accumulating evidence suggests that epigenetic alterations play an important role in chemically-induced carcinogenesis. Although the epigenome and genome may be equally... (Review)
Review
Accumulating evidence suggests that epigenetic alterations play an important role in chemically-induced carcinogenesis. Although the epigenome and genome may be equally important in carcinogenicity, the genotoxicity of chemical agents and exposure-related transcriptomic responses have been more thoroughly studied and characterized. To better understand the evidence for epigenetic alterations of human carcinogens, and the potential association with genotoxic endpoints, we conducted a systematic review of published studies of genotoxic carcinogens that reported epigenetic endpoints. Specifically, we searched for publications reporting epigenetic effects for the 28 agents and occupations included in Monograph Volume 100F of the International Agency for the Research on Cancer (IARC) that were classified as "carcinogenic to humans" (Group 1) with strong evidence of genotoxic mechanisms of carcinogenesis. We identified a total of 158 studies that evaluated epigenetic alterations for 12 of these 28 carcinogenic agents and occupations (1,3-butadiene, 4-aminobiphenyl, aflatoxins, benzene, benzidine, benzo[a]pyrene, coke production, formaldehyde, occupational exposure as a painter, sulfur mustard, and vinyl chloride). Aberrant DNA methylation was most commonly studied, followed by altered expression of non-coding RNAs and histone changes (totaling 85, 59 and 25 studies, respectively). For 3 carcinogens (aflatoxins, benzene and benzo[a]pyrene), 10 or more studies reported epigenetic effects. However, epigenetic studies were sparse for the remaining 9 carcinogens; for 4 agents, only 1 or 2 published reports were identified. While further research is needed to better identify carcinogenesis-associated epigenetic perturbations for many potential carcinogens, published reports on specific epigenetic endpoints can be systematically identified and increasingly incorporated in cancer hazard assessments.
Topics: Animals; Carcinogenicity Tests; Carcinogens; Environmental Exposure; Epigenesis, Genetic; Gene Expression Regulation; Genetic Association Studies; Genetic Predisposition to Disease; Genetic Variation; Humans; Mutagenicity Tests; Mutagens; Occupational Exposure
PubMed: 27234561
DOI: 10.1016/j.mrrev.2016.03.004 -
Hepatitis Monthly Mar 2016Hepatocellular carcinoma (HCC) is the second most common cancer-related death worldwide. Although many factors including dietary aflatoxin B1 (AFB1) and alcoholic and... (Review)
Review
CONTEXT
Hepatocellular carcinoma (HCC) is the second most common cancer-related death worldwide. Although many factors including dietary aflatoxin B1 (AFB1) and alcoholic and non-alcoholic fatty liver diseases can lead to HCC, globally most HCC cases are due to hepatitis B virus (HBV) and hepatitis C virus (HCV). Considering the importance of these viral factors in most HCC cases and relative lack of literature from eastern Mediterranean region office of world health organization (EMRO) countries and the Middle East, we decided to perform this systematic review to find distribution of viral etiology of HCC in these regions.
EVIDENCE ACQUISITION
In this systemic review, we included all studies from 1 January 1989 to 1 September 2015 with at least 20 samples that measured HBV surface antigen (HBsAg) and antibodies to HCV (anti-HCV). The authors searched MEDLINE, Embase, Popline, Web of Science and WHO indexed databases. We searched the following MeSH terms; hepatocellular carcinoma, hepatitis B virus and hepatitis C virus or hepacvirus. Only studies using second- and third-generation HCV assays were included. Only articles studying HCC patients from EMRO countries and the Middle East were analyzed. Duplicate results that reported the same cases more than once were found and omitted. Studies in English and Farsi were reviewed. If the study was eligible, we recorded the following data; the first author, publication year and journal, study population and number and percentage of patients with different serologic statuses.
RESULTS
We found 44 studies from 12 countries in EMRO and the Middle East. HCC cases from Iran, Lebanon, Turkey and Yemen were mainly due to HBV, while those of North African nations (Egypt, Tunisia, Morocco, Algeria and Somalia) in addition to Saudi Arabia and Pakistan were mostly HCV related. Sudan showed a high seronegativity and HBV infection in its HCC cases. Unfortunately, some countries from EMRO and the Middle East did not have eligible studies.
CONCLUSIONS
HBV and HCV are important culprits of HCC in EMRO countries and the Middle East and different nations need different strategies to tackle them accordingly. Countries with high rates of HBV such as Turkey should continue their HBV vaccination and also increase sanitation. Nations with high HCV rates such as Egypt should maintain their blood product monitoring in addition to increased sanitation, especially regarding injection drug users (IDU).
PubMed: 27226803
DOI: 10.5812/hepatmon.35106