•PAH recoveries using conventional methods deviated from EU accepted criteria.•Recoveries of Heavy PAHs by SUPRAS ranged from 71.33 to 112.23% in chicken.•Baseline shift in coffee samples prepared ...with SUPRAS.•PAHs’ recoveries in chicken and coffee by QuEChERS were 62.3–103.9% and 52.6–78.7%.•SUPRAS and QuEChERS needed 69–139 fold lower energy than conventional methods.
This study compared different extraction methods sonication, alkaline hydrolysis, supramolecular solvent microextraction (SUPRAS) and Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) along with their greenness. An analytical method was validated for determination of USEPA’s listed 16 polycyclic aromatic hydrocarbons’ (PAHs) in cooked chicken and roasted coffee using high pressure liquid chromatography-fluorescence detector (HPLC-FLD) with a C18 column. The recoveries with QuEChERS ranged between 62.26 and 103.85% (except Naphthalene and Fluorene) and 52.63–78.69% (except Naphthalene) for chicken and coffee respectively while poor recoveries were observed with conventional methods. With SUPRAS, heavy PAHs’ recovery in chicken was 71.33–112.23%. Limits of detection (LOD) were 0.03–0.06 ng/mL, regression coefficient values were 0.97–0.99 for 6.25–37.50 ng/mL quantification range. Relative standard deviation was found to be below 22%. The time and energy consumption per sample was 42.50 and 69.06 fold and 77.52 and 139.50 fold less with SUPRAS and QuEChERS method respectively as compared to alkaline hydrolysis.
Background soils were collected from 70 locations on a latitudinal transect in the United Kingdom and Norway in 2008, ten years after they had first been sampled in 1998. The soils were analyzed for ...polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and organochlorine pesticides (OCs), to see whether there had been any change in the loadings or distributions of these persistent organic pollutants (POPs). The same transect has also been used to sample air between the mid-1990s and the present, so the air and soil spatial and temporal trends provide information on air-soil transfers, source-receptor relationships, long-range atmospheric transport (LRAT), and recycling phenomena. Comparisons of the 2008 and 1998 data sets show a general decline for PBDEs in surface soil, and a smaller averaged net decline of PCBs. Changes between the years were observed for total POP concentrations in soil and also for correlations with site and sample characteristics assumed to affect those concentrations. POP concentrations were correlated to distance and strength of possible sources, a relationship that became weaker in the 2008 data. Fractionation, a commonly discussed process for the global cycling of POPs was also lost in the 2008 data. As in 1998, soil organic matter content continues to have a strong influence on the loadings of POPs in surface soils, but changes in the PCB loads were noted. These factors indicate an approach to air–surface soil equilibrium and a lessening of the influence of primary sources on POP concentrations in soil between 1998 and 2008.
Tandoori cooking is a popular food preparation method in India involving a unique combination of grilling, baking, barbecuing, and roasting processes. This study determined the levels of 16 ...polycyclic aromatic hydrocarbons (PAHs) in tandoori chicken and assessed the associated health risk. The sum of 16 PAHs concentration ranged from 25.4 to 3733 μg/kg with an average of 440 ± 853 μg/kg. Analyzed samples demonstrated major contribution of 2, 3, and 4 ring PAHs. Diagnostic ratios identified combustion and high-temperature processes as the main source favoring PAHs generation in these samples. Benzo(a)pyrene equivalents and incremental lifetime cancer risk (ILCR) estimates for different population groups (boys, girls, adult males, adult females, elderly males, elderly females) associated with dietary intake of these products ranged from 6.88E-05 to 4.13E-03 and 1.63E-08 to 1.72E-06, respectively. Since the ILCR values fell within the safe limits (1E-06, i.e., nonsignificant), the consumption of tandoori chicken may be considered as safe. The study emphasizes the need for extensive studies on PAHs formation in tandoori food products.
This study was envisaged to understand the effect of increasing pyrolysis temperature on the Cr(VI) removal potential of the groundnut shells derived biochars. The biochars were prepared at four ...different pyrolysis temperatures (350 °C, 450 °C, 550 °C, 650 °C) and were used unmodified to examine the adsorption potential for Cr(VI). Influence of biochar dose (1–10 g/L), pHinitial (2–10), Cr(VI)initial (10–500 mg/L) on Cr(VI) adsorptions; adsorption kinetics and isotherms were investigated. The observations suggested that the pyrolysis temperature is the key player in deciding the physicochemical properties as well the adsorption potential of the biochars. SEM and FTIR analysis suggested significant morphological and functional transformations in biochars with increasing pyrolysis temperature. The pHinitial was found to be the most profound adsorption parameter determining the adsorption potential of the biochars. The Cr(VI) adsorption capacity of the biochars decreased with the increase of the pyrolysis temperature (142.87–31.25 mg/L) as well as the solution pHinitial. All the biochars attained 100% removal efficiency with 50 mg/L of Cr(VI)initial and GNSB/350 achieved it in the minimum time (10 h) among all the biochars. GNSB/350 showed promising Langmuir adsorption capacity of 142.87 mg/L (pH 2, Tadsorption 30 °C, Cr(VI)initial 10–500 mg/L). In addition, the adsorption mechanism was found to be a synergistic action of chemi/physi-sorption with monolayer adsorption. Hence, the pyrolysis temperature significantly altered the physicochemical properties of the biochars, which highly influenced the adsorption performance of biochars.
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Concentration, composition and sources of polycyclic aromatic hydrocarbons (PAHs) in kitchen depositions from different sampling categories such as restaurants, university mess and houses were ...investigated, and associated human exposure risk through dietary intake, inhalation and dermal contact was determined. The PAHs in the samples were extracted by supramolecular solvent based microextraction (SUPRAS) method and the concentrations were determined by high pressure liquid chromatography (HPLC) with fluorescence detection. The mean of Σ16PAHs concentration was found to be the highest (386.09 ± 413.17 mg kg−1) for restaurants followed by mess (80.91 ± 92.81 mg kg−1) and houses (24.65 ± 10.52 mg kg−1). Traffic sources were found to be predominant contributors of PAHs in restaurants while cooking activities were the sources for mess and houses. Three- and five-ring PAHs were prominent in restaurants and mess samples while two- and three-ring PAHs contributed the most in houses samples. Non-cancer risk (hazard index) from exposure to these PAHs was found to be within safe limits i.e. 2.70E-09 to 7.46E-08. Estimated lifetime cancer risk was found to range from 2.46E-06 to 7.81E-04 from exposure to these PAHs and indicates significant risk due to exceeding the guideline value of 10−6.
•The Σ16 PAH ranged from 15.46 to 1096.20 mg kg−1 in kitchen depositions.•Higher PAHs contamination was found in restaurants than mess and houses.•Concentration of heavy PAHs was higher in samples from restaurants than mess and houses.•Estimated ILCR is higher than guideline value, exhibits serious health concerns.•Σ16PAHs significantly correlated with proximity to traffic sites or use of exhaust tools.
The polycyclic aromatic hydrocarbons' (PAHs) exposure through day to day cooking activities has been a serious concern for human health due to their carcinogenic nature. Given the Covid-19 ...conditions, where people are spending extended time indoors, the likely exposure to these compounds will increase for the members involved/not involved in cooking. In this context, this review summarizes different studies undertaken worldwide on PAHs from cooking activities, the sources of exposure (fumes/emissions, dust/depositions), effect of scale (households/restaurants/neighborhoods) of cooking, monitoring process, risk assessment (air sampling and urinary metabolites), global distribution pattern. Proportionately higher number of studies was focused on cooking fumes and emissions while very limited studies aimed at kitchen depositions and dust. Most of the studies have not reported the size of particulate matter considered for determining PAHs exposure from cooking fumes and emissions. The evaluation of reported data becomes more complicated due to difference in sampling and expression units, the number and types of PAHs (parent, oxygenated-PAHs, i.e., o-PAHs, nitro-PAHs, i.e., n-PAHs) studied/found, lack of other intrinsic information (site and control parameters), lack of specific regulations etc. Therefore, such studies require method standardization for future policy development. This review also highlights the gaps and challenges in existing knowledge and future prospects.
Sweet lime (Citrus limetta) peel biochar was obtained by slow pyrolysis of raw biomass at 450 °C with 5 °C/min heating rate. Proximate and ultimate analysis, physico-chemical characterization of the ...biochar was done. Batch adsorption experiments for Cr(VI) removal were performed with varying pH, biochar dose, contact time and initial Cr(VI) concentrations. It took 8–24 h to reach the equilibrium at 30 °C for varying Cr(VI) concentrations. The biochar was found to possess higher adsorption capacity (100 mg/g) than the adsorbents reported in several previous studies. Langmuir adsorption isotherm and pseudo second order model best explained the experimental data, suggesting monolayer adsorption as the dominant mechanism. Chemical interaction, ion exchange of solute and sorbate ions and physical adsorption also contributed into Cr(VI) adsorption process. Further, Cr(VI) adsorption was found to be a multistep process. The findings suggested that sweet lime peel biochar can be utilized as a low cost and efficient alternative for Cr(VI) removal, which could be useful for aqueous solutions, as well as to promote overall protection against soil and water degradation and pollution.
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•Abundantly available, underutilized waste biomass is used for biochar preparation.•Without any activation process, 100 mg/g Cr(VI) adsorption efficiency was achieved.•Cr(VI) adsorption was a result of synergic action of physical and chemical factors.•Pseudo second order kinetic model best described the experimental data.•Langmuir adsorption isotherm was found to best fit the adsorption data.
Polycyclic Aromatic Hydrocarbons (PAHs) are environmental carcinogens which are produced in food during their processing and thermal treatment. Consumption of such foods results in diverse diseases ...including cancer in humans, raising a serious need to either prevent formation of these compounds in food or reduce and remove these carcinogens once they are formed. The concern is very important and reasonable as diet contributes to 88–98% exposure. Some of the processes followed to prevent PAHs formation include regulation of the cooking/processing practices/methods and revolves around deodorization and refining of oil as well as sugars, choosing right type of oil and frying process, choosing liquid smoking process over traditional practices, reducing fat content of product and preferring the right part of product (especially in meats), roasting and baking products at lower time-temperature combinations with preferences to electric oven and indirect processes, using the right heat medium (wood chips for barbequeing/charcoal grilling, using correct wraps for food products to prevent direct contact with heat and fat drippings and much more. Though these processes may be followed at household and commercial scales and have been stated in several published literature, but the absence of PAHs may not always be guaranteed in food products. This leaves the scientific community to attempt and develop strategies which can remove the already existing PAHs from food products and needs to be extensively reviewed and worked in future. This review bridges the PAHs’ reduction and removal strategies different types of ingredients (marination, spice addition), the specific kind of packaging (aluminium foils, plastic films, charred barrels, paraffin rind), the heating treatments (irradiation, microwave preheating, defatting, brewing etc.), but also the characteristics of adsorbents and filters used (active charcoal, diatomaceous earth, zeolite filters, molecular sieves), together with innovative removal apparatus with emphasis on biological and physical-chemical factors influencing their formation/reduction or removal/degradation, mainly in heat-processed food such as composition and surface adsorption properties, etc.. The overall goal is to develop the understanding of the interactions amongst all factors affecting PAHs removal and draw recommendations based on conclusions of scientific evidence and propose future challenges in this area.
Strategies for reduction and removal of PAHs from processed food products. Display omitted
Searching similarity between a pair of shapes or data is an important problem in data analysis and visualization. The problem of computing similarity measures using scalar topology has been studied ...extensively and proven useful in the shape and data matching. Even though multi-field or multivariate (consists of multiple scalar fields) topology reveals richer topological features, research on building tools for computing similarity measures using multi-field topology is still in its infancy. In the current article, we propose a novel similarity measure between two piecewise-linear multi-fields based on their multi-resolution Reeb spaces - a newly developed data-structure that captures the topology of a multi-field. Overall, our method consists of two steps: (i) building a multi-resolution Reeb space corresponding to each of the multi-fields and (ii) proposing a similarity measure between two multi-resolution Reeb spaces by computing a list of topologically consistent matching pairs (of nodes) and the similarity between them. We demonstrate the effectiveness of the proposed similarity measure in detecting topological features from real time-varying multi-field data in two application domains - one from computational physics and one from computational chemistry.
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