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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 -
Environment International Dec 2019Bees are exposed to a wide range of multiple chemicals "chemical mixtures" from anthropogenic (e.g. plant protection products or veterinary products) or natural origin... (Meta-Analysis)
Meta-Analysis
Bees are exposed to a wide range of multiple chemicals "chemical mixtures" from anthropogenic (e.g. plant protection products or veterinary products) or natural origin (e.g. mycotoxins, plant toxins). Quantifying the relative impact of multiple chemicals on bee health compared with other environmental stressors (e.g. varroa, viruses, and nutrition) has been identified as a priority to support the development of holistic risk assessment methods. Here, extensive literature searches and data collection of available laboratory studies on combined toxicity data for binary mixtures of pesticides and non-chemical stressors has been performed for honey bees (Apis mellifera), wild bees (Bombus spp.) and solitary bee species (Osmia spp.). From 957 screened publications, 14 publications provided 218 binary mixture toxicity data mostly for acute mortality (lethal dose: LD) after contact exposure (61%), with fewer studies reporting chronic oral toxicity (20%) and acute oral LC values (19%). From the data collection, available dose response data for 92 binary mixtures were modelled using a Toxic Unit (TU) approach and the MIXTOX modelling tool to test assumptions of combined toxicity i.e. concentration addition (CA), and interactions (i.e. synergism, antagonism). The magnitude of interactions was quantified as the Model Deviation Ratio (MDR). The CA model applied to 17% of cases while synergism and antagonism were observed for 72% (MDR > 1.25) and 11% (MDR < 0.83) respectively. Most synergistic effects (55%) were observed as interactions between sterol-biosynthesis-inhibiting (SBI) fungicides and insecticide/acaricide. The mechanisms behind such synergistic effects of binary mixtures in bees are known to involve direct cytochrome P450 (CYP) inhibition, resulting in an increase in internal dose and toxicity of the binary mixture. Moreover, bees are known to have the lowest number of CYP copies and other detoxification enzymes in the insect kingdom. In the light of these findings, occurrence of these binary mixtures in relevant crops (frequency and concentrations) would need to be investigated. Addressing this exposure dimension remains critical to characterise the likelihood and plausibility of such interactions to occur under field realistic conditions. Finally, data gaps and further work for the development of risk assessment methods to assess multiple stressors in bees including chemicals and non-chemical stressors in bees are discussed.
Topics: Animals; Bees; Fungicides, Industrial; Lethal Dose 50; Pesticides; Risk Assessment
PubMed: 31683157
DOI: 10.1016/j.envint.2019.105256 -
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 -
Annals of Global Health Nov 2018Stunting, a form of malnutrition characterized by impaired linear growth in the first two years of life, affects one quarter of children globally. While nutritional...
BACKGROUND
Stunting, a form of malnutrition characterized by impaired linear growth in the first two years of life, affects one quarter of children globally. While nutritional status remains the key cause of stunting, there is evidence that environmental risk factors are associated with stunting.
OBJECTIVE
The objective of this review is to explore the current literature and compile the environmental risk factors that have been associated with stunting. Further, we seek to discover which risk factors act independently of nutritional intake.
METHODS
A systematic search of the literature was performed using PubMed, EMBASE, Scopus, TOXNET, and CINAHL. A search of the grey literature was conducted. Papers were included in this review if they examined an association between childhood stunting and exposure to environmental risk factors.
FINDINGS
We included 71 reports in the final analysis. The included studies showed that foodborne mycotoxins, a lack of adequate sanitation, dirt floors in the home, poor quality cooking fuels, and inadequate local waste disposal are associated with an increased risk of childhood stunting. Access to safe water sources was studied in a large number of studies, but the results remain inconclusive due to inconsistent study findings. Limited studies were available for arsenic, mercury, and environmental tobacco, and thus their role in stunting remains inconclusive. The identified research did not control for nutritional intake. A causal model identified solid fuel use and foodborne mycotoxins as being environmental risk factors with the potential to have direct effects on childhood growth.
CONCLUSIONS
A diverse range of environmental risk factors are, to varying degrees, associated with stunting, demonstrating the importance of considering how the environment interacts with nutrition. Health promotion activities may be more effective if they consider environmental factors alongside nutritional interventions.
Topics: Child; Child Nutrition Disorders; Environmental Exposure; Global Health; Growth Disorders; Health Promotion; Humans; Nutritional Status; Risk Factors
PubMed: 30779500
DOI: 10.9204/aogh.2361 -
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 -
Medicine Dec 2016As environmental risk factors (ERFs) play an important role in the pathogenesis of Kashin-Beck disease (KBD), it is important to identify the interaction between ERFs... (Meta-Analysis)
Meta-Analysis Review
As environmental risk factors (ERFs) play an important role in the pathogenesis of Kashin-Beck disease (KBD), it is important to identify the interaction between ERFs and differentially expression genes (DEGs) in KBD. The environmental response genes (ERGs) were analyzed in cartilage of KBD in comparison to normal controls.We searched 5 English and 3 Chinese databases from inception to September 2015, to identify case-control studies that examined ERFs for KBD using integrative meta-analysis and systematic review. Total RNA was isolated from articular cartilage of KBD patients and healthy controls. Human whole genome microarray chip (Agilent) was used to analyze the amplified, labeled, and hybridized total RNA, and the validated microarray data were partially verified using real-time quantitative polymerase chain reaction (qRT-PCR). The ERGs were derived from the Comparative Toxicogenomics Database. The identified ERGs were subjected to KEGG pathway enrichment, biological process (BP), and interaction network analyses using the Database for Annotation, Visualization and Integrated Discovery (DAVID) v6.7, and STRING.The trace elements (selenium and iodine), vitamin E, and polluted grains (T-2 toxin/HT-2 toxin, deoxynivalenol, and nivalenol) were identified as the ERFs for KBD using meta-analysis and review. We identified 21 upregulated ERGs and 7 downregulated ERGs in cartilage with KBD compared with healthy controls, which involved in apoptosis, metabolism, and growth and development. KEGG pathway enrichment analysis found that 2 significant pathways were involved with PI3K-Akt signaling pathway and P53 signaling pathway, and gene ontology function analysis found 3 BPs involved with apoptosis, death, and cell death in KBD cartilage.According to previous results and our own research, we suggest that the trace element selenium and vitamin E induce PI3K-Akt signaling pathway and the mycotoxins (T-2 toxin/HT-2 toxin and DON) induce P53 signaling pathway, contributing to the development of KBD, and chondrocyte apoptosis and cell death.
Topics: Apoptosis; Cartilage, Articular; Case-Control Studies; Down-Regulation; Gene Expression; Gene Expression Profiling; Gene Ontology; Gene-Environment Interaction; Humans; Kashin-Beck Disease; Oncogene Protein v-akt; Phosphatidylinositol 3-Kinases; Risk Factors; Signal Transduction; Tumor Suppressor Protein p53; Up-Regulation
PubMed: 28033256
DOI: 10.1097/MD.0000000000005669