Utilising an LC-MS/MS-based multi-biomarker approach to assess mycotoxin exposure in the Bangkok metropolitan area and surrounding provinces

Human exposures to mycotoxins through dietary intake are a major health hazard and may result in various pathophysiological effects. Although Thailand is a country at increased risk due to its climatic conditions, no comprehensive dataset is available to perform proper exposure assessment of its population with regard to mycotoxins. Therefore, this pilot study was conducted to investigate and evaluate the exposure levels of major mycotoxins (aflatoxin B₁, ochratoxin A, fumonisins, zearalenone and trichothecenes). Sixty first-morning urine samples were collected from healthy volunteers who live in the Bangkok metropolitan area and surrounding provinces (Pathumthani, Nonthaburi, Samutprakarn and Samutsakorn). Urine samples were analysed by a LC-MS/MS-based multi-biomarker method following a so-called ‘dilute and shoot’ approach. Results generally indicated low mycotoxin exposures in most individuals through the determination of the four biomarkers that were detected in urine samples, i.e. aflatoxin M₁, ochratoxin A (OTA), as well as the deoxynivalenol (DON) metabolites DON-3-glucuronide and DON-15-glucuronide in 10 of 60 individuals. The maximum concentrations were used to estimate the daily intake confirming that none of the individuals exceeded the tolerable daily intake (TDI) of DON (maximum 26% of TDI) or OTA (maximum 22% of TDI). However, the maximum exposure of aflatoxin B₁, estimated to be 0.91 µg (kg bw)^–1 day^–1, should raise some concerns and suggests further studies utilising a more sensitive method. Low exposure to Fusarium toxins was also confirmed by the absence of zearalenone, α-zearalanol, β-zearalanol and zearalenone-14-glucuronide as well as T-2 toxin, HT-2 toxin, nivalenol and free DON. This is the first multi-mycotoxin biomarker study performed in Southeast Asia.     

Toxic epidemics caused by alimentary exposure to pesticides: a review.

Toxic epidemics have become a serious problem during the twentieth century, due mainly to the huge expansion over the last 50 years of the chemical industry, which has placed tens of thousands of new synthetic organic compounds in the human environment. In the particular case of chemical pesticides, their undiscriminating, widespread use, and harmful potential has been demonstrated by the epidemics generated by accidental contamination by pesticides of foods consumed by man, resulting in high mortality and morbidity rates. We have analysed the main characteristics of 63 outbreaks of toxicity caused by alimentary exposure to pesticides described in the scientific literature of this century, with the aim of increasing knowledge and understanding of the factors that are conducive to them or that trigger their onset. Such episodes are good indicators of the incorrect use of these products and serve to demonstrate failures of the available safety systems. We conclude by identifying some preventive measures that could be used to avoid their future repetition.     

Five-stage environmental exposure assessment strategy for mixtures: gasoline as a case study

A five-stage strategy is suggested for conducting an exposure assessment of mixtures that may contain numerous chemical components. The stages are: (1) determination of mixture composition and variability, (2) selection of component groups within the mixture and documentation of criteria used for this selection, (3) compilation of relevant property data for each group, (4) assessment of environmental fate of each group, and (5) assessment of environmental and human exposure to each group and to the mixture as a whole. A subsequent step is the assessment of environmental and/or human risk associated with the individual and aggregate exposure to each group. The approach is illustrated by application to gasoline, which is treated as 24 component groups or hydrocarbon blocks. Focusing on stages 2-4, the illustration shows that the groups display widely different environmental fates as a result of their different physicochemical properties, degradation half-lives, and mode-of-entry into the environment. As a result, the relative proportions of groups in each environmental medium (such as air and water) differ greatly from that of the original mixture. It is thus important to treat gasoline and similar mixtures as a number of component groups instead of as a single substance. A generic procedure is suggested in which the model is run for unit emissions of each component group to air, water, and soil. These results are compiled into matrices that can then be conveniently scaled to actual emission rates without rerunning the model. Methods for determining subsequent exposure and risk are also briefly outlined.     

Integrated rural wine tourism: a case study approach

Using the Niagara Peninsula Appellation as the case study, qualitative research was employed through the use of interviews conducted with wineries and industry associations, in an attempt to answer two specific questions: (1) how does the wine industry and wine tourism aid in the development of Niagara’s rural area using the integrated rural tourism (IRT) concept, and (2) how can IRT aid in rural development through direct, experiential, conservation, development, and synergistic benefits. It is apparent that the seven components of IRT provide a reasonable framework to analyse the ability of IRT to realize benefits, although that the addition of marketing and future needs/desires as components improve its explanatory power. Using the modified IRT framework, this research found that wine tourism has derived direct, experiential, conservation, and synergistic benefits, with work still to be undertaken in order to improve upon tourism’s positive impacts in Niagara and peripherally rural areas more generally in the areas of community engagement and improved industry synergy.     

Long-term dietary exposure to lead in young European children: comparing a pan-European approach with a national exposure assessment

Long-term dietary exposures to lead in young children were calculated by combining food consumption data of 11 European countries categorised using harmonised broad food categories with occurrence data on lead from different Member States (pan-European approach). The results of the assessment in children living in the Netherlands were compared with a long-term lead intake assessment in the same group using Dutch lead concentration data and linking the consumption and concentration data at the highest possible level of detail. Exposures obtained with the pan-European approach were higher than the national exposure calculations. For both assessments cereals contributed most to the exposure. The lower dietary exposure in the national study was due to the use of lower lead concentrations and a more optimal linkage of food consumption and concentration data. When a pan-European approach, using a harmonised food categorisation system and “European” concentration data, results in a possible health risk related to the intake of an environmental chemical for a certain country, it is advisable to refine this assessment, as part of a tiered approach, using national occurrence data, including an optimised linkage between foods analysed and consumed for that country. In the case of lack of occurrence data, these data can be supplemented with data from the “European” concentration database or by generating additional concentration data at country level.     

Food web pathway determines how selenium affects aquatic ecosystems: a San Francisco Bay case study

Chemical contaminants disrupt ecosystems, but specific effects may be under-appreciated when poorly known processes such as uptake mechanisms, uptake via diet, food preferences, and food web dynamics are influential. Here we show that a combination of food web structure and the physiology of trace element accumulation explain why some species in San Francisco Bay are threatened by a relatively low level of selenium contamination and some are not. Bivalves and crustacean zooplankton form the base of two dominant food webs in estuaries. The dominant bivalve Potamocorbula amurensis has a 10-fold slower rate constant of loss for selenium than do common crustaceans such as copepods and the mysid Neomysis mercedis (rate constant of loss, ke = 0.025, 0.155, and 0.25 d(-1), respectively). The result is much higher selenium concentrations in the bivalve than in the crustaceans. Stable isotope analyses show that this difference is propagated up the respective food webs in San Francisco Bay. Several predators of bivalves have tissue concentrations of selenium that exceed thresholds thought to be associated with teratogenesis or reproductive failure (liver Se >15 microg g(-1) dry weight). Deformities typical of selenium-induced teratogenesis were observed in one of these species. Concentrations of selenium in tissues of predators of zooplankton are less than the thresholds. Basic physiological and ecological processes can drive wide differences in exposure and effects among species, but such processes are rarely considered in traditional evaluations of contaminant impacts.     

How to routinely assess transition,adhesion and survival of probiotics into the gut: a case study on propionibacteria

Two commercial promising probiotic strains (Propionibacterium jensenii and Propionibacterium freudenreichii) were studied to evaluate two basic probiotic requisites (adhesion and survival during the transit into the gut); two commercial starter cultures (Lactobacillus plantarum and Lactobacillus delbrueckii subsp. bulgaricus) were used as references. As an additional goal, the technological robustness was evaluated as growth as a function of pH, temperature and salt. Adhesion was studied as biofilm formation and hydrophobicity, whereas a simplified protocol was used to simulate the transit into the gut, along with the assessment of survival at pH 2.5 and in the presence of 0.3% bile salts. Propionibacteria were hydrophobic and form biofilm on glass slides, thus confirming the correlation of these properties and with the ability to adhere. None of the strains survived after the simulation of the transit into the gut, but this property could be induced in propionibacteria using a simple protocol of adaptive evolution. This paper suggests the possibility of using hydrophobicity as a screening tool to assess adhesion in propionibacteria and highlights the necessity of using a complete protocol of simulation of the gut to study the resistance to the conditions of stomach and intestine to avoid false‐positive results.     

The promise of a community-based approach to managing severe malnutrition: A case study from Ethiopia

BACKGROUND: Community-based therapeutic care (CTC) is a new strategy in the arsenal of techniques to manage complex nutritional emergencies in rural communities. The CTC approach uses a newly developed ready-to-use therapeutic food, Plumpynut, to rehabilitate severely malnourished children in their home communities. Emerging literature has suggested the CTC strategy yielded results that were superior to those of programs limited to therapeutic feeding centers, as measured by rates of coverage and numbers of children rehabilitated. OBJECTIVE: To compare the effectiveness of the CTC strategy in combination with conventional treatments for acute malnutrition. The expectation was that this program would support the growing consensus on the effectiveness of CTC strategies. METHODS: Data from monitoring the initial phase of program implementation were reviewed to ascertain program impact. The number of children participating and the outcome of their participation were assessed. RESULTS: Families became key participants in the rehabilitation of their children, and communities became strengthened through the mobilization of local networks and the improved knowledge base of local health workers. Recovery rates were comparable with international standards, and coverage far exceeded that of traditional center-based care. CONCLUSIONS: CTC is an important tool to effectively address nutritional emergencies and may be a valuable entry point for long-term development, since it fosters capacity building and improvement in local communities. CTC programs may eventually be viewed as the entry point for more sustained development-oriented interventions, thus helping make the transition from relief to development.     

Reliable estimation of dietary exposure to furan from coffee: An automatic vending machine as a case study

Worldwide Food Safety Agencies have classified furan as carcinogenic and cytotoxic due to its effects in animal studies, and it has been associated with harmful effects to human health. It has been pointed out that coffee consumption is the major contributor to dietary furan exposure for adults. However, furan is highly volatile and its losses due to volatilization in the cup during the time expend to consume the coffee brew should be taken into account for a realistic estimation of the levels of furan exposure for humans. The aim of this study was to estimate the furan exposure to humans considering the time for consumption after preparation of the fresh beverage. Furan was determined in coffee brews acquired from automatic coffee vending machines placed in areas with high density of population. Furan levels in coffee beverages ranged from 11 to 262 ng/mL (mean = 171 ± 59.8). Furthermore, five different scenarios were settled immediately after the acquisition of coffee brews from the coffee vending machines in order to assess a realistic estimation of furan exposure. Furan content in coffee decreased from 170 up to 4 ng/mL after simulating the behavior of coffee consumption (~ 74% after standing at room temperature for 5 min, ~ 64% after stirring for 30 s and standing at room temperature up to 5 min, ~ 94% after stirring for 5 min, ~ 97% after 8 h in a sealed thermo and ~ 37% after being cooled one week at a fridge). These results suggest that it is mandatory to establish very precisely the furan levels in the final ready-to-drink beverage in order to obtain reliable estimations of the daily intake from coffee and to define potential strategies for mitigation. Furan intake from coffee ranged from 0.02 to 0.43 μg/kg b.w./day, resulting in a mean exposure of 0.31 μg/kg b.w./day.     

Learning to know what you like: A case study of repeated exposure to ethnic flavors

This study investigated changes in the liking of seasoned food products with novel flavors among Indonesian consumers. Subjects were repeatedly exposed to kangkung (Indonesian-style stir-fried spinach) seasoned with four flavor variants of Korean fermented soybean paste: sweet, umami, hot and spicy, and fermented. Seventy-eight subjects completed the experiment, which consisted of three taste-test trials and four exposure conditioning sessions. Consumer taste tests were applied (1) at the beginning of the experiment, (2) immediately after the completion of four exposure conditioning sessions, and (3) 1 month after the second taste test. The liking ratings of the samples were evaluated as well as the reasons for liking and disliking them. General linear model analysis, general linear mixed model analysis for repeated measure, chi-square analysis, and correspondence analysis were applied to the data. Additionally, cluster analysis was performed to compare the acceptance levels and the drivers of liking in the two groups who had different overall liking baselines. The hedonic and perceptual discrimination abilities of the samples increased for the entire group as the repeated-exposure sessions progressed. Moreover, overall liking score increased with exposures for most of the samples. When consumers were clustered into two groups based on the similarity of their initial preferences for the samples, the initial heterogeneity of sample liking between the two groups decreased in the later stages of the taste-test trials. Stronger agreement between subjects was observed on the preferences for kangkung samples as a whole group after being repeatedly exposed to the samples.     

Food design: from the methodological approach to the case study of low-calorie syrups

New ingredients help the creation of novel foods. However, the management of ingredient combination remains a challenge for manufacturers since the definition of successful formulas still requires a number of trials and errors which are too time consuming to meet market demand. The authors describe a predictive approach to food design, based on the systematic exploitation of the functional properties of each potential ingredient. As an example, the methodology developed was applied to the formulation of syrups which were requested to have the same sensorial properties as those of the traditional product but a lower calorie content.     

Laser ablation-ICP-MS analysis of dissected tissue: a conservation-minded approach to assessing contaminant exposure

Minimally invasive sampling techniques are an essential ecotoxicological tool for continuous assessment of contaminant exposure and in instances where it is not desirable or practical to sacrifice the animal. In this paper, we report on the application of laser ablation-ICP-MS (LA-ICP-MS) for sampling of minute (approximately 1 mg, 2-3 mm) tail clips of the banded water snake, Nerodia fasciata, as a means to assess contaminant exposure. The snakes were split into three treatments (n = 8) and were fed three increasing levels (control, medium, and high) of fish contaminated with As, Se, and Sr for 24 months. LA-ICP-MS concentrations of tail clips for all three elements were significantly correlated with the remaining whole tail concentration determined by homogenization, acid digestion, and ICP-MS analysis. Additionally, LA-ICP-MS concentrations for As and Se in the tail clip were similar to the acid digestion solution analysis values for the whole tail, which suggests that these elements are homogeneously distributed. Strontium concentrations were underestimated by LA-ICP-MS when compared to whole tail concentrations. Statistical analysis showed that LA-ICP-MS tail clip concentrations differed significantly according to dietary treatment. Posterior probability error rates from nonparametric discriminant function analysis indicated that LA-ICP-MS analysis of tail clips was useful for predicting exposure to Se with only a 4% probability of misclassification among treatments. Errors associated with misclassification of As were greater (17%) but this was, in part, related to the low concentrations of As in the tail (<1 ppm for the highest treatment). Taken together, the findings from this study suggest that LA-ICP-MS of microdissected tissue shows promise as a nondestructive technique for conservation-minded ecotoxicological studies.     

PhetoFate: a new approach in accounting for the contribution of indirect photolysis of pesticides and pharmaceuticals in surface waters

A new approach was developed to account for the contribution of indirect photolysis of pesticides and pharmaceuticals in which laboratory test conditions are similar to those prevalent in the aqueous environment. Rates of photolysis as a function of water composition were investigated for several aquatic contaminants. Using the laboratory-based test system, PhotoFate, the dependence of phototransformation rates on concentrations of natural water constituents that are radical producers and scavengers (nitrate, colored dissolved organic matter, bicarbonate) was studied. Mean half-lives of the model compounds in the presence of water constituents were compared to their direct photolysis half-lives to assess the contribution of photosensitized reactions to their fate in surface waters. Reactions mediated by .OH were predominant in waters with high nitrate concentrations. Colored dissolved organic matter (cDOM) acted mainly as a radiation filter and had a more important role in scavenging radicals than in their production. However, in low nitrate waters, the contribution of cDOM-derived reactive intermediates to the degradation of parent compounds became more apparent