Climate change and the health impact of aflatoxins exposure in Portugal – an overview

Climate change has been indicated as a driver for food safety issues worldwide, mainly due to the impact on the occurrence of food safety hazards at various stages of food chain. Mycotoxins, natural contaminants produced by fungi, are among the most important of such hazards. Aflatoxins, which have the highest acute and chronic toxicity of all mycotoxins, assume particular importance. A recent study predicted aflatoxin contamination in maize and wheat crops in Europe within the next 100 years and aflatoxin B1 is predicted to become a food safety issue in Europe, especially in the most probable scenario of climate change (+2°C). This review discusses the potential influence of climate change on the health risk associated to aflatoxins dietary exposure of Portuguese population. We estimated the burden of disease associated to the current aflatoxin exposure for Portuguese population in terms of Disability Adjusted Life Years (DALYs). It is expected that in the future the number of DALYs and the associated cases of hepatocellular carcinoma due to aflatoxins exposure will increase due to climate change. The topics highlighted through this review, including the potential impact on health of the Portuguese population through the dietary exposure to aflatoxins, should represent an alert for the potential consequences of an incompletely explored perspective of climate change. Politics and decision-makers should be involved and committed to implement effective measures to deal with climate change issues and to reduce its possible consequences. This review constitutes a contribution for the prioritisation of strategies to face the unequal burden of effects of weather-related hazards in Portugal and across Europe.     

Safety assessment of β-nitropropionic acid: a monograph in support of an acceptable daily intake in humans

Several molds, Aspergillus, Penicillium and to a lesser extent, Arthrinium can produce β-nitropropionic acid (NPA). The presence of NPA has been detected in at least four families of higher plants. Use of Aspergillus as an economic mould in the production of foods and the accidental contamination of foods provides for an historically lengthy and widespread exposure of humans to NPA. Despite widespread consumption of foods containing NPA, human poisoning by NPA is rare and confined to circumstances involving gross mishandling of the food products. NPA is absorbed in the gastrointestinal tract, enters the circulation and is metabolized to nitrite, although some may bind succinate dehydrogenase upon oxidation. The primary mechanism of toxicity of NPA is as a “suicide” substrate (non-competitive inhibitor) of succinate dehydrogenase, an enzyme of the mitochondrial membrane (part of Complex II) that catalyzes the oxidation of succinate to fumarate, which is manifested as pathological change in striatal areas of the brain. The physiological damage caused by NPA metabolic compromise resembles the genetic disorder, Huntington's disease. This resemblance has been extensively exploited in recent years to understand the mechanisms of neurodegeneration. There are no irreversible effects resulting from ingestion of subthreshold doses of NPA, nor is there any accumulation of NPA in the body. The LD₅₀ dose of NPA for mice and rats is between 60 and 120 mg/kg. In long-term studies, NPA did not exhibit carcinogenicity or chronic toxicity. The reported no observed adverse effect level (NOAEL) for NPA is 2.5 and 3.75 mg/kg/day for male and female rats, respectively. Results of mutagenicity tests are mixed, but positive assays can be traced back to the use of a single impure sample of NPA. Based on the NOAEL of the chronic rodent bioassay, an ADI of 25 μg/kg/day or 1.750 mg/day for a 70 kg human is appropriate.     

Dietary exposure and health risk assessment for 11 minerals and trace elements in Yaoundé: the Cameroonian Total Diet Study

Dietary exposure to 11 elements was assessed by the Total Diet Study (TDS) method. Sixty-four pooled samples representing 96.5% of the diet in Yaoundé, Cameroon, were prepared as consumed before analysis. Consumption data were sourced from a household budget survey. Dietary exposures were compared with nutritional or health-based guidance values (HBGV) and to worldwide TDS results. Elevated prevalence of inadequate intake was estimated for calcium (71.6%), iron (89.7%), magnesium (31.8%), zinc (46.9%) and selenium (87.3%). The percentage of the study population exceeding the tolerable upper intake levels was estimated as <3.2% for calcium, iron, magnesium, zinc and cobalt; 19.1% of the population exceeded the HBGV for sodium. No exceedance of the HBGV for inorganic mercury was predicted in the population. The margin of exposure ranged from 0.91 to 25.0 for inorganic arsenic depending on the reference point. The “Fish” food group was the highest contributor to intake for calcium (65%), cobalt (32%) and selenium (96%). This group was the highest contributor to the exposure to total arsenic (71%) and organic mercury (96%). The “Cereals and cereal products” highly contributed to iron (26%), zinc (26%) and chromium (25%) intakes. The “Tubers and starches” highly contributed to magnesium (39%) and potassium (52%) intakes. This study highlights the dietary deficiency of some essential elements and a low dietary exposure to toxic elements in Yaoundé.     

Aflatoxin–albumin adducts and correlation with decreased serum levels of vitamins A and E in an adult Ghanaian population

A study of aflatoxin (AF) exposure and the levels of vitamins A and E was carried out with a group of 507 Ghanaian participants. AFB₁–albumin adducts (AFB-AA) were measured by radioimmunoassay and vitamins A and E were measured by high-performance liquid chromatography (HPLC). The average level of serum AFB-AA was 0.94 ± 0.64 (range = 0.1–4.44) pmol mg^?1 albumin. Mean levels of vitamins A and E were 1.32 ± 0.48 (range = 0.41–4.85) µmol l^?1 and 15.68 ± 4.12 (range = 6.35–30.40) µmol l^?1, respectively. A significantly negative correlation was found between serum AFB-AA and vitamin A levels (r = ?0.110, p = 0.013). An even stronger, significant negative, correlation was found between serum AFB-AA and vitamin E levels (r = ?0.149, p < 0.001). Serum AFB-AA levels were statistically higher (median = 0.985 pmol mg^?1 albumin) in subjects who had low levels of both vitamins A and E as compared with the levels (median = 0.741 pmol mg^?1 albumin) subjects who had high vitamins A and E levels (p _trend = 0.001). To verify these findings, blood samples were again collected from 165 of the 507 people 3 months after the initial collection. Significantly negative correlations were confirmed between levels of serum AFB-AA and both vitamins A (r = ?0.232, p = 0.003) and E (r = ?0.178, p = 0.023). Again, high serum AFB-AA concentrations (median = 1.578 pmol mg^?1 albumin) were found in subjects with low levels of vitamins A and E compared with the concentrations (median = 1.381 pmol mg^?1 albumin) in subjects with high levels of vitamins A and E (p _trend = 0.002). These data show that AF exposure was associated with decreased levels of serum vitamins A and E in high-risk human populations, which may significantly influence the incidence of AF-related adverse health effects.     

Microplastic in bottled natural mineral water – literature review and considerations on exposure and risk assessment

ABSTRACT

Microplastics have been ubiquitously found and identified in aquatic and terrestrial environments for several years. Due to their occurrence in the oceans, microplastics were also found and characterised in seafood products and in other foods and beverages such as beer, honey and table salt. Very recently, microplastic particles were also determined in bottled mineral water. The objective of this publication is to present and discuss a compilation of the currently available literature data on microplastics in bottled mineral water. The related oral exposure of the consumer from substances present in microplastics and from the plastics particles themselves is estimated and toxicological arguments for and considerations on risk assessment from the consumption of bottled mineral water containing microplastics are presented. Exposure estimations based on the reported microplastic amounts found in mineral water and the assumption of total mass transfer of small molecules like additives and oligomers present in the plastic would not raise a safety concern. Available toxicokinetic data suggests that marginal fraction of the ingested low amount of microplastics can be absorbed, if at all, the conclusion is very likely that the reported amounts present in bottled mineral water do not raise a safety concern for the consumer. Considering the use of plastic materials in our daily life, occurrence of microplastics in beverages is likely a minor exposure pathway for plastic particles. Due to recent progress in analytical methods and the public discussion on plastics marine litter, public concern about eating and drinking microplastics with food, and related safety issues was raised. However, a better data basis for exposure estimates and risk assessment would be very helpful to better accommodate consumer concerns. The intention of this paper is to deliver a contribution to this topic taking the bottled mineral water as a case example.     

A review of the current situation of aflatoxin M1 in cow’s milk in Serbia: risk assessment and regulatory aspects

ABSTRACT

The aim of this systematic review is to provide information regarding the incidence and levels of aflatoxin M₁ (AFM₁) in raw and heat processed cow’s milk in Serbia during 2015–16 and to compare these with collected data on the occurrence of AFM₁ in raw milk and dairy products during the last decade in our region. Estimation of dietary exposure (EDI) and hazard index (HI) calculations for different age groups of the population were also carried out, based on the AFM₁ content of milk samples and on available food consumption data in Serbia. AFM₁ was detected in 69.9% (984/1408) of raw milk samples in 2015 versus 84.9% (3094/3646) in 2016, while in heat-processed milk, AFM₁ was detected in 77.8% (364/468) in 2015 versus 98.5% (753/765) in 2016. On the basis of the obtained results, 450 (9%) of raw and 14 (1.1%) of heat-processed milk samples were contaminated with AFM₁ levels above the maximum permitted level in Serbia (0.25 μg kg^?1). However, a large percentage of raw and heat processed milk in Serbia (30.1% and 17.3%, respectively) was contaminated with AFM₁ levels above the maximum permitted level regulated in the European Union (0.05 μg kg^?1). Therefore, in order to protect consumer health, it is extremely important to further control the level of aflatoxins in milk, and this should be considered as a high priority for risk management actions.     

Aflatoxin M1 in processed milk and infant formulae and corresponding exposure of adult population in Serbia in 2013–2014

Aflatoxin M₁ (AFM1) occurrence was analysed in 80 samples of milk and 21 samples of infant formulae on the Serbian market, using high-performance liquid chromatography with fluorescence detection. All milk samples collected in 2013 showed AFM1 contamination in the range 0.02–0.32 μg kg^?1, with a mean level of 0.13 μg kg^?1. The EU maximum level for AFM1 in milk (0.05 μg kg^?1) was exceeded in 75% of the samples. In 2014, AFM1 was found in 83%, 70%, 80% and 58% of the samples collected in April, July, September and December, respectively, exceeding the limit in 5% of the samples taken in July. The additional number of liver cancer cases per year associated with exposure to AFM1 was estimated to be 0.004 in the adult population. Regarding infant formulae, AFM1 was found in only one sample.     

Effect of shear thinning on aspiration – Toward making solutions for judging the risk of aspiration

Polysaccharide solutions containing a contrast medium were prepared so that their viscosity at 50 s⁻¹, which was reported as a shear rate in the oral cavity, is the same but different at other shear rates. Preparation procedure of such solutions based on heat treatment using widely used polysaccharides in foods is described, and the rheological properties of these solutions are discussed in relation with flow behaviours in the swallowing process. Videofluorographic observation was performed for healthy persons and patients and compared with rheological characteristics of these solutions to understand the mechanism of aspiration. It was shown that the degree of aspiration depended on the degree of shear thinning of polysaccharide solutions. This study showed the possibility to find what kind of fluid induces the aspiration and to reduce the risk of aspiration in dysphagic patients by controlling the food rheology.     

Authors' perspective: what is the optimum intake of vitamin C in humans?

The recommended dietary allowance (RDA) of vitamin C has traditionally been based on the prevention of the vitamin C deficiency disease, scurvy. While higher intakes of vitamin C may exert additional health benefits, the limited Phase III randomized placebo-controlled trials (RCTs) of vitamin C supplementation have not found consistent benefit with respect to chronic disease prevention. To date, this has precluded upward adjustments of the current RDA. Here we argue that Phase III RCTs-designed principally to test the safety and efficacy of pharmaceutical drugs-are ill suited to assess the health benefits of essential nutrients; and the currently available scientific evidence is sufficient to determine the optimum intake of vitamin C in humans. This evidence establishes biological plausibility and mechanisms of action for vitamin C in the primary prevention of coronary heart disease, stroke, and cancer; and is buttressed by consistent data from prospective cohort studies based on blood analysis or dietary intake and well-designed Phase II RCTs. These RCTs show that vitamin C supplementation lowers hypertension, endothelial dysfunction, chronic inflammation, and Helicobacter pylori infection, which are independent risk factors of cardiovascular diseases and certain cancers. Furthermore, vitamin C acts as a biological antioxidant that can lower elevated levels of oxidative stress, which also may contribute to chronic disease prevention. Based on the combined evidence from human metabolic, pharmacokinetic, and observational studies and Phase II RCTs, we conclude that 200 mg per day is the optimum dietary intake of vitamin C for the majority of the adult population to maximize the vitamin's potential health benefits with the least risk of inadequacy or adverse health effects.     

Identification of an acidic α-amylase from Alicyclobacillus sp. A4 and assessment of its application in the starch industry

An acidic α-amylase was purified from thermoacidophilic Alicyclobacillus sp. A4 by ion exchange chromatography with 22% recovery, and showed a molecular mass of 64 kDa by SDS-PAGE. Its amino acid sequence was determined by sequencing three internal peptides and the complete genome of strain A4, and shared highest identity (64%) with Alicyclobacillusacidocaldarius α-amylase. Compared with other reported α-amylases, the purified enzyme had some distinct characteristics. The optimal activity was found to occur at 75 °C and pH 4.2, similar to the glucamylase widely used in the starch industry. The enzyme was Ca²⁺ independent, and had strong ability to digest raw starch (96.71%) with commercial glucamylase in one step. These properties of the purified enzyme make up the deficiency of the commercial α-amylases currently used and avoid repeated adjustment of pH and temperature in double-enzymatic sugar-making process. The purified enzyme will be commercially valuable in the starch industry.     

Human health risk of dietary intake of organochlorine pesticide residues in bovine meat and tissues from Veracruz, México

Tissue distribution patterns of organochlorine pesticides in bovine carcasses varied significantly among seasons, geographic locations and tissues. The highest concentrations of Σ-DDT during the dry season were detected in lungs from Paso de Ovejas (2,834.90μg/kg lipid) and, during the rainy season, Lindane and Σ-HCH in muscle and lung samples from Paso de Ovejas (995.80 and 1,690.10μg/kg lipid). Estimated daily intakes of γ-HCH and Σ-DDT (3.35 and 1.22μg/kg bw/day) through consumption of muscle tissues from Paso de Ovejas and Puente Nacional during the rainy season showed the highest contribution. During the rainy season the highest non-cancer Hazard Ratios estimated corresponded to γ-HCH (3.97) and Σ-DDT (4.39) detected in muscle samples from Puente Nacional. The highest Hazard Ratios of cancer risk to the 95th centile daily consumption through meat corresponded to p,p'-DDT from Alvarado (7.76E+06) and from Paso de Ovejas for γ-HCH (1.50E+05) during rainy season. The results indicate potential non- and carcinogenic risks to consumer health through meat consumption.     

Dietary advanced glycation end products--a risk to human health? A call for an interdisciplinary debate

Physiological consequences resulting from protein-bound Maillard compounds in foods must be discussed carefully. This was the idea behind the debate, which is put for discussion by the papers by Sebekova and Somoza, who argued for the motion that dietary advanced glycation end products (AGEs) are a health risk, and by Ames, who provided evidence against the motion. In this two excellent reviews, numerous arguments based on papers published in high-impact journals are given for each of the opinions. The fact that no final conclusion can be drawn, may reflect the need for a more comprehensive examination of this issue in the future. For a deeper understanding of biological consequences resulting from heated foods, the relationships between well-defined biological effects and well-characterized chemical structures must be studied. Prerequisite for this is profound chemistry--pure compounds, exact concentrations, and unambiguous analytical techniques. A real "risk assessment" is much too complex than to leave it up to one discipline alone. It must be a comprehensive and interdisciplinary approach, joining the resources of biology, medicine, and chemistry.     

Determination of aflatoxins in edible oil from markets in Hebei Province of China by liquid chromatography–tandem mass spectrometry

Analysis of aflatoxin B₁ (AFB₁), B₂ (AFB₂), G₁ (AFG₁) and G₂ (AFG₂) in 76 edible oil samples (peanut oil, soybean oil, corn embryo oil and blended oil) was performed by liquid chromatography–tandem mass spectrometry (LC–MS/MS). The oils were sampled from three areas (Shijiazhuang, Baoding and Tangshan) of Hebei Province of China. AFB₁ was detected in 22 samples representing 28.9%, followed by AFB₂ (7.89%) and AFG₁ (3.95%), while no AFG₂ contamination was detected in any samples. AFB₁ levels in oil samples ranged 0.14–2.72?µg?kg^?1 and AFB₂ ranged 0.15–0.36?µg?kg^?1, while lower levels of 0.01–0.02?µg?kg^?1 for AFG₁ were recorded. The paper is part of an on-going investigation of aflatoxin contamination in Chinese edible oils.     

Dietary polyphenols against metabolic disorders: How far have we progressed in the understanding of the molecular mechanisms of action of these compounds?

The aim of this review was to critically assess the evidence supporting the metabolic and anti-inflammatory effects attributed to polyphenols and the potential mechanisms of action underlying these effects. The metabolic and anti-inflammatory properties of polyphenols and polyphenol-rich products have been shown mostly in rodents. These compounds appear to share multiple mechanisms of action at different body sites (gastrointestinal tract, microbiota, host organs) and the responsible molecules may be the original plant compounds, the microbial metabolites and (or) the host derived conjugates. Polyphenols may modify digestion and absorption of nutrients, microbiota composition and metabolism, and host tissue metabolic pathways but none of these mechanisms have been fully demonstrated in vivo and thus, more and better designed studies are needed. Furthermore, human clinical trials show inconsistent evidence of the metabolic and inflammation regulatory properties of polyphenols. Some of the principal limitations of these studies as well as recommendations to further progress in the understanding of the metabolic effects and mechanisms of action of polyphenols are discussed.     

On the assessment of fracture in brittle foods II. Biting or chewing?

In this study crispness assessment in different dry-crisp foods were evaluated. Roasted almonds with different degrees of roasting and two different types of extruded snacks, wheat crusts and cheese balls, at different water activities were used as samples. Crispness behaviour was characterised by using coupled sound–texture measurements and by sensory evaluation with the use of a consumer panel. Instrumental texture measurements were made using compression and penetration tests. While in the almond samples the compression test discriminated better than the penetration test among the samples, in both kinds of snacks the compression with the tooth-like probe proved to be as good as penetration tests to assess crispy characteristics. Consumers evaluated the samples by chewing with the back molars or by biting with the incisive teeth. The results obtained in sensory evaluation were similar to instrumental results. Consumers were able to better discriminate between the almond samples by chewing than by biting but in the snacks samples the ratings both by biting and chewing modalities were very similar and showing the same discrimination level. These findings could have useful applications: for panel training, at the time of naming attributes and defining how they are evaluated; also, to obtain the most of sensory-consumer correlations, having in mind that the “ease of breakdown” in the mouth is proved to contribute to the relative preferences among narrow texture ranges within products.     

Using participant ratings to construct food image paradigms for use in the Australian population – A pilot study

In human research, images of food are often used as cues in place of real foods. To elicit anticipatory responses in targeted populations (e.g. prompting changes in metabolic hormones, invoking food cravings), cultural differences and population norms with regard to food preferences need to be considered. This pilot study aimed to construct two image paradigms (healthy vs. hyperpalatable foods) for experimental use within the Australian population. A dataset of 200 images (from the licenced database Food-pics and internet sources), representative of healthy and hyperpalatable foods commonly consumed in Australia, was compiled by research dietitians. Ten male and female adults volunteered to view the images. Participants categorised each image as either healthy food or ‘junk food’ (i.e. hyperpalatable food), and rated each image according to three criteria: 1) familiarity of the food displayed; 2) recognisability of the food; and 3) appetisingness of the food. Overall, agreement with a priori categories was high for both healthy and hyperpalatable food images, 87.3% and 87.7% respectively. The food images with the lowest overall ratings (score <7 out of possible 9) were removed from the dataset and the final paradigms each contain 75 images. The healthy food paradigm contains foods from the five core food groups (fruit, vegetables, grains and cereals, meat and meat alternatives, dairy foods), and the hyperpalatable food paradigm contains non-core foods (sweet and savoury discretionary choice foods). The paradigms represent a broad range of commonly consumed foods that will be relevant for prospective projects utilising food cues in Australian adults.     

Formation of amorphous sugar in the syrup film – a key factor in modelling of industrial sugar drying

A mathematical model of the steady-state sugar drying operation in a cross-flow rotating drum dryer is proposed. Although the model is based on the classic two-film concept of simultaneous heat and mass transfer, it also allows for the formation and growth of a thin layer of amorphous sugar due to local supersaturation of the sugar syrup. The formation of amorphous sugar is a result of the competition between crystallization and drying kinetics. The onset of amorphization is assumed to occur when the system moves from the metastable zone to the labile zone on the sucrose–water phase diagram. The rate of sucrose amorphization is controlled by the conditions prevailing on the metastability limit. Diffusivity of water through the amorphous sugar, the only adjustable parameter of the proposed model, has been determined by fitting sugar moisture data from an industrial Louvre-type dryer. The layer of amorphous sugar plays a critical role during the falling-rate period of drying. Generally, models ignoring its presence tend to overestimate the moisture removal rate. The presented model predicts a dramatic decline of the evaporation rate once the amorphous sugar begins to form which is observed in the industrial practice. The effect of key operating parameters such as air flow rate, hot air temperature, and crystal size on the dryer performance is also discussed.     

Modelling bacterial growth in quantitative microbiological risk assessment: is it possible?

Quantitative microbiological risk assessment (QMRA), predictive modelling and HACCP may be used as tools to increase food safety and can be integrated fruitfully for many purposes. However, when QMRA is applied for public health issues like the evaluation of the status of public health, existing predictive models may not be suited to model bacterial growth. In this context, precise quantification of risks is more important than in the context of food manufacturing alone. In this paper, the modular process risk model (MPRM) is briefly introduced as a QMRA modelling framework. This framework can be used to model the transmission of pathogens through any food pathway, by assigning one of six basic processes (modules) to each of the processing steps. Bacterial growth is one of these basic processes. For QMRA, models of bacterial growth need to be expressed in terms of probability, for example to predict the probability that a critical concentration is reached within a certain amount of time. In contrast, available predictive models are developed and validated to produce point estimates of population sizes and therefore do not fit with this requirement. Recent experience from a European risk assessment project is discussed to illustrate some of the problems that may arise when predictive growth models are used in QMRA. It is suggested that a new type of predictive models needs to be developed that incorporates modelling of variability and uncertainty in growth.