Feed intake, for non-smokers, is the first route of contamination to polycyclic aromatic hydrocarbons (PAHs), which are potentially toxic compounds via ingestion. Investigations are focused on the ...presence of PAHs in fruits and vegetables. Transfer of PAHs can occur from air and soil during cultivation. They can also appear prior to consumption during storage, transport or cooking processes.
Rather low amounts of PAHs are usually detected in raw fruits and vegetables. Quantities are between 0.01 and 0.5 μg kg-1 (wet weight) for compounds classified as priority pollutants by the US Environmental Protection Agency (EPA). However, several studies point out that concentrations of some PAHs can exceed 0.5 μg kg-1 wet weight in diverse fruits and vegetables and even reach 5 μg kg-1. Amounts can be very different depending on the surrounding area of the crops, the aromatic hydrocarbon, or even the product itself. PAHs content is usually higher for products grown near roadways or in urban regions than in rural areas. Trace level of compounds such as phenanthrene, fluoranthene and pyrene have been found in quite every raw fruit and vegetable. Relative high amounts of lighter PAHs such as naphthalene, acenaphthylene, and acenaphthene have been found in some of them.
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•PAHs contents are usually low in fruits and vegetables versus other food products.•Air/soil of cultivation, transport, storage are sources of PAHs in fruits/vegetables.•In fruits and vegetables, PAHs levels mainly depend on contamination of crop areas.•PAHs preferentially accumulate in peels and light compounds are predominant.•Cooking processes may be responsible for PAHs input into fruits and vegetables.
This review article aims to report origins and levels of Polycyclic Aromatic Hydrocarbons in fruits and vegetables, with a critical view on methods used for their determination in such food matrices.
This study aimed at developing a new method for the extraction of polycyclic aromatic hydrocarbons (PAHs) in polyurethane foam (PUF). In the field of PAH monitoring, passive samplers using PUF disks ...are widely used. However, current extraction methods are time and solvent consuming. This new method employs 3 times a sixteenth of the PUF disk, with method detection limits (MDL) values below 5 and 13 ng/sampler for 3- and 4-rings PAHs, respectively. The use of only parts of the disk allows extraction by ultrasounds using exclusively 120 mL of ethanol, making it environmentally friendly. Ethanolic extracts are then purified and concentrated using microextraction by packed sorbent (MEPS) before GC-MS analyses. This method was applied for an environmental survey in a French urban area with an oceanic climate. Variations in PAH concentrations were observed depending on the site studied (urban, traffic, periurban and rural), as well as temporal variations.
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•Development of a new method for PAHs extractions from PUF disks using ultrasounds.•Ethanol used for PAHs extraction to promote an environmentally friendly method.•Application for the control of PAHs in an urban area with an oceanic climate.
A total of 207 volatile compounds were identified in extracts of four French labeled brandies: Armagnac, Cognac, Calvados, and Mirabelle. Relative levels of all components were determined using GC-MS ...after integration of a selected peak of the mass spectrum of each. Each type of brandy could be clearly discriminated using PLS-DA statistical analyses based on these levels. French Mirabelle spirit, which was studied for the first time, was characterized by higher levels of many aldehydes and acetals and by the presence of compounds having an odd number of carbons together with benzaldehyde and some of its derivatives. Many possible derivatives of acrolein and high amounts of butan-2-ol were rather specific for the volatile composition of Calvados. The most important difference between the two wine-based samples seemed to be directly linked to the distillation system used. Many furanic compounds are specific to Cognac, whereas two or three compounds such as 1-(ethoxyethoxy)-2-methylbutane and γ-eudesmol were specific to Armagnac. These two brandies presented rather high distributions of isobutanol and isopentanols, whereas Mirabelle and Calvados compositions offer more concentrated aliphatic linear alcohols.
Forest fires and biomass burning are known to generate aromatic hydrocarbons via incomplete combustions, due to high moisture, insufficient temperature, and oxygen content. These emission sources are ...particularly concerning because generated smokes cannot be treated and aromatic hydrocarbons can deposit on plant foods.
The aim of this work was to study the potential deposition and absorption of monocyclic and polycyclic aromatic hydrocarbons in plant after exposure to smokes generated by burning wood. Thus, apples, used as a representative plant food model, were intentionally exposed to wood burning emissions for lengths of time varying from 1 to 2 h. Among benzene, toluene, ethylbenzene, xylenes, toluene appeared to be the most abundant compound. Concerning PAHs, linden wood combustion led to predominant deposition of compounds with molecular weights lower than 202 g/mol with the highest levels detected for phenanthrene.
Aromatic hydrocarbons from wood combustion were mainly deposited on apple epicarp, and their transfer to the mesocarp was limited. Diagnostic ratio, used for the determination of PAHs emission source, was calculated with PAHs contents deposited on apple skin. Results were consistent with values proposed in the literature for the identification of biomass combustion.
Model microbial communities are often studied to better understand interactions and fluxes during fermentation processes. However, models that take into account the potential impact of bacteriophages ...(phages), which are recognized as drivers of microbial communities, are scarce, especially in fermented foods. This study aimed at investigating the behavior of a cider model microbial community, which was subjected to disturbance in the presence or absence of phages and at two different temperatures (25 °C and 15 °C). The model microbial community was composed of three lactic acid bacteria (LAB) strains belonging to the species Liquorilactobacillus mali, Leuconostoc mesenteroides and Oenococcus oeni, and of a Saccharomyces uvarum yeast strain. Two phages were selected, targeting L. mali and Ln. mesenteroides strains. In order to follow the behavior of the microbial community model, the phages and microbial strains were enumerated at several time points, and the metabolic signatures (sugar consumption, production of organic acids and volatile organic compounds) of the model microbial community were monitored. At 25 °C, the community with phages (P) was significantly closer to the control condition (C) than to the condition without phages (D). Microbial levels were similar between conditions C and P, which were characterized by high concentrations of compounds such as 2-phenylethanol, ethyl octanoate and isoamyl alcohol, and more globally by a more complex metabolic signature than that of condition D. In condition D, L. mali and Ln. mesenteroides were dominant while S. uvarum and O. oeni were less present, and this condition was characterized by a high concentration of ethyl lactate. At 15 °C, condition P differed from conditions C and D, as Ln. mesenteroides was not detected while the other strains all reached approximately the same levels. The metabolic range of condition P was less important than for conditions C and D. The current study showed that the influence of phages on the model microbial community dynamics and metabolisms after a disturbance phenomenon was temperature-dependent.
Urban gardening is becoming increasingly popular. Air pollution, which is a major concern in cities might, however, threaten food safety and thus must be assessed. Health risks arise particularly ...from toxic persistent organic pollutants such as Polycyclic Aromatic Hydrocarbons (PAHs) which are formed by incomplete combustion. A first assessment of crop contamination in two different atmospheric environments in the urban area of Nice reveals a predominance of light PAHs. These pollutants present in the gaseous phase, seem to bioaccumulate while heavy PAHs are absent in vegetation. By understanding the PAH sources and their behavior in the atmosphere but also by analyzing the spatial and temporal data since the European directive in 2004, a link between concentrations found in vegetables grown in experimental gardens and PAH cadastral emission data is presented. The first results could be used as a possible guidance for urban agriculture.
This work highlights the first assessment of crop contamination by Polycyclic Aromatic Hydrocarbons (PAHs) in two different atmospheric environments in the urban area of Nice revealing the sensitivity of crops to atmospheric persistent organic pollutants. Light PAHs present in the gaseous phase, seem to bioaccumulate while heavy PAHs are absent in vegetation. A link between concentrations found in vegetables and PAH cadastral emission data is presented. The first results could be used as a possible guidance for urban agriculture.
•Use of HS-SPME and UAE/SPE followed by GC–MS for aromatic hydrocarbons determination.•Development and validation for quantification of BTEX and 12 PAHs in fruits.•Methods showed good validation ...results.•Methods provided reliable estimation of aromatic hydrocarbons content at μg/kg level.•Statistical results showed adaptability of methods to various fruits.
Two reliable and complementary approaches have been established for the determination of volatile and semi-volatile aromatic hydrocarbons at μg/kg level in fruits. Headspace solid-phase microextraction was used for extraction of monocyclic and light polycyclic aromatic hydrocarbons (MW ≤ 178 g/mol). Method based on ultrasound-assisted extraction followed by solid-phase extraction allowed extraction of heavy polycyclic aromatic hydrocarbons (MW ≥ 202 g/mol). Extraction techniques coupled with analysis by gas chromatography-mass spectrometry were successfully applied to 18 aromatic compounds in different fruit matrices (apple, pear, plum, and grape). Applicability of methods to these several fruits had been statistically verified through ANOVA test, by comparison of linear regression responses (slopes) of calibrations curves. Developed methods showed good linearity (r2 = 0.919–0.999) within a range of concentrations from 0 to 10 μg/kg wet weight and acceptable values were obtained for repeatability (RSD = 1–22%) and intermediate precision (RSD 3–30%). Limits of detection and quantification did not exceed 0.2 and 0.6 μg/kg, respectively, except for fluorene in grape (0.5 and 1.8 μg/kg, respectively). Extraction and analytical methodologies implemented in the present study allow sensitive determination of trace levels of monocyclic and polycyclic aromatic hydrocarbons in fruit.
Structurally modified polycyclic aromatic hydrocarbons (PAHs) such as nitrated PAHs (nitro-PAHs) and oxygenated PAHs (oxy-PAHs) can be incriminated in the total toxicity of polycyclic aromatic ...compounds (PACs) fraction in the environment. Compared to nitro-PAHs, oxy-PAHs have been poorly studied. Oxy-PAHs covers compounds with different moieties such as polycyclic aromatic ketones (PAKs) and polycyclic aromatic quinones (PAQs). In this review, we have compiled exhaustively all the data available on the sources, the fate, and the occurrence of oxy-PAHs focusing on the most ubiquitous ones in the environment, ie PAKs and PAQs. Data concerning their genotoxicity, mutagenicity and tumor promotion potential for humans are also provided based on the mode-of-action analysis framework. Mutagenicity results based on the limited number of oxy-PAHs tested, are unequivocal on the concern they represent. Their omission in mutagenic/carcinogenic risk has caused a dramatic underestimation of cancer risk. On the basis of environmental and genotoxicological data, we suggest prioritized 4 major oxy-PAHs molecules in ecotoxicological and toxicological studies, namely 6 H-benzocdpyren-6-one (BPO), 7,12-benzaanthracenequinone (BAQ), 5,12-naphthacenequinone (NCQ) and 11 H-benzobfluoren-11-one (BbFO). We also propose to develop biomarkers of exposure and/or risk for these compounds, for example by quantification of DNA adducts.
► Current methods which allow to analyse aroma–related interactions are reviewed. ► The purposes, strong and weak points of the methods are reported and contrasted. ► Their ability to reveal ...interactions in model and real food matrices is discussed. ► Future approaches which allow to study complex stimuli are presented. ► This review should help researchers to choose the right approach to study aroma–related interactions.
Understanding the mechanisms involved in the perception of food aroma is one of the major objectives of flavour studies. Yet, it remains difficult to explain this perception due to the diversity of cross–modal interactions that occur between aroma, taste and texture during food consumption. Various sensory and instrumental methods have been developed to describe such interactions and to highlight their origins. Each of them has its own advantages and drawbacks. This paper describes the methods used over the past decade in order to help researchers choose the right approach to study aroma–related interactions. Their objectives, weaknesses and strengths are reported and contrasted. Their ability to reveal interactions in model and real food matrices is also discussed. Finally, innovative original approaches are presented.
There is no universal method that can be applied to extract bound extracellular polymeric substances (EPS) from benthic diatoms of intertidal sediments without causing cell lysis. Six extraction ...methods were tested on a diatom culture of Navicula jeffreyi to establish the best compromise between high yields of carbohydrate extraction and minimum cell lysis. Extraction with distilled water provoked cell lysis (as already known). The five other extraction methods (dowex resin, artificial seawater of half salinity and extractions after pretreatment with gluteraldehyde by three methods: water, dowex water and dowex buffer) did not provoke cell lysis as shown by transmission electronic microscopy. This result was confirmed by the minimum release of internal compounds (protein, ATP) and by the low proportions of glucose in dowex-extracted EPS compared with the water-extracted EPS, from which the high glucose content must be inferred as contamination by the chrysolaminaran. The extraction with dowex resin resulted in the second-highest concentration of carbohydrate after the water extraction and the EPS were especially rich in deoxy sugars, hence increasing the hydrophobic feature of these substances. For these reasons, we recommend extraction with dowex, which is also the best method for extracting bound EPS from other biofilms such as in activated sludges.
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